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Stephen Wolfram: Complexity and the Fabric of Reality | Lex Fridman Podcast #234


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The following is a conversation with Stephen Wolfram, his third time on the podcast.
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He's a computer scientist, mathematician, theoretical physicist, and the founder of
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Wolfram Research, a company behind Mathematica, Wolfram Alpha, Wolfram Language,
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and the new Wolfram Physics Project. This conversation is a wild, technical roller coaster
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ride through topics of complexity, mathematics, physics, computing, and consciousness. I think
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this is what this podcast is becoming, a wild ride. Some episodes are about physics, some about
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robots, some are about war and power, some are about the human condition and our search for meaning,
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and some are just what the comedian Tim Dillon calls fun. This is the Lex Friedman podcast.
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To support it, please check out the sponsors in the description. And now here's my conversation
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with Stephen Wolfram. Almost 20 years ago, you published a new kind of science,
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where you presented a study of complexity and an approach for modeling of complex systems.
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So let us return again to the core idea of complexity. What is complexity?
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I don't know. I think that's not the most interesting question. It's like,
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if you ask a biologist, what is life? That's not the question they care the most about.
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What I was interested in is how does something that we would usually identify as complexity
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arise in nature? And I got interested in that question 50 years ago, which is really embarrassingly
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a long time ago. How does snowflakes get to have complicated forms? How do galaxies get to have
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complicated shapes? How do living systems get produced? Things like that. And the question is,
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what's the underlying scientific basis for those kinds of things? And the thing that I was at first
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very surprised by, because I've been doing physics and particle physics and fancy mathematical
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physics and so on, and it's like, I know all this fancy stuff. I should be able to solve this basic
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science question. And I couldn't. This was like early maybe 1980ish time frame. And it's like, okay,
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what can one do to understand the sort of basic secret that nature seems to have? Because it
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seems like nature, you look around in the natural world, it's full of incredibly complicated forms.
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You look at sort of most engineered kinds of things. For instance, they tend to be, you know,
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we've got sort of circles and lines and things like this. And the question is, what secret does
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nature have that lets it make all this complexity that we in doing engineering, for example,
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don't naturally seem to have? And so that was the kind of the thing that I got interested in.
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And then the question was, could I understand that with things like mathematical physics? Well,
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it didn't work very well. So then I got to thinking about, okay, is there some other way to try to
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understand this? And then the question was, if you're going to look at some system in nature,
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how do you make a model for that system, for what that system does? So a model is some abstract
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representation of the system, some formal representation of the system. What is the
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raw material that you can make that model out of? And so what I realized was, well, actually,
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programs are really good source of raw material for making models of things. And, you know,
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in terms of my personal history, to me, that seemed really obvious. And the reason it seemed
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really obvious is because I just spent several years building this big piece of software that
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was sort of a predecessor to mathematical and morphine language, then called SMP, symbolic
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manipulation program, which was something that had this idea of starting from just these computational
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primitives and building up everything one had to build up. And so kind of the notion of, well,
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let's just try and make models by starting from computational primitives and seeing what we can
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build up. That seemed like a totally obvious thing to do. In retrospect, it might not have been
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externally quite so obvious, but it was obvious to me at the time, given the path that I happened
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to have been on. So, you know, so that got me into this question of, let's use programs to model
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what happens in nature. And the question then is, well, what kind of programs? And, you know,
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we're used to programs that you write for some particular purpose, and it's a big long piece
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of code, and it does some specific thing. But what I got interested in was, okay, if you just go out
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into the sort of computational universe of possible programs, you say, take the simplest
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program you can imagine, what does it do? And so I started studying these things called cellular
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automata. Actually, I didn't know at first they were called cellular automata, but I found that out
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subsequently. But it's just a line of cells, you know, each one is black or white. And it's just
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some rule that says the color of the cell is determined by the color that it had on the previous
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step. And it's two neighbors on the previous step. And I had initially thought that's, you know,
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sufficiently simple setup is not going to do anything interesting. It's always going to be
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simple, no complexity, simple rule, simple behavior. Okay, but then I actually ran the
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computer experiment, which is pretty easy to do. I mean, it probably took a few hours
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originally. And the results were not what I'd expected at all. Now, needless to say,
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in the way that science actually works, the results that I got a lot of unexpected things,
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which I thought were really interesting, but the really strongest result, which was already right
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there in the printouts I made, I didn't really understand for a couple more years. So it was,
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it was not, you know, the compressed version of the story is you run the experiment and you
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immediately see what's going on. But I wasn't smart enough to do that, so to speak. But the big,
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the big thing is, even with very simple rules of that type, sort of the minimal, tiniest program,
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sort of the, the one line program or something, it's possible to get very complicated behavior.
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My, my favorite example is the single rule 30, which is a particular cellular automaton rule,
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you just started off in one black cell, and it makes this really complicated pattern.
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And so that, for me, was sort of a critical discovery that then kind of said, playing back
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onto, you know, how does nature make complexity? I sort of realized that might be how it does it.
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That might be kind of the secret that it's using is that in this kind of computational
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universe of possible programs, it's actually pretty easy to get programs where even though
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the program is simple, the behavior when you run the program is not simple at all. And that was,
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so for me, that was the, the kind of the, the story of kind of how that, that was sort of the,
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the indication that one had got an idea of what the sort of secret that nature uses
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to make complexity and the complexity, how complexity can be made in other places.
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Now, if you say, what is complexity, you know, it's, it's complexity is, it's not easy to tell
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what's going on. That's the informal version of what is complexity.
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But there is something going on, but there's a rule to know what, right?
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Well, no, the rules can generate just randomness, right?
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Well, that's not obvious. In other words, that's not obvious at all.
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And it wasn't what I expected. It's not what people's intuition had been and has been for,
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you know, for a long time. That is one might think you have a rule, you can tell there's a
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rule behind it. I mean, it's just like, you know, the early, you know, robots in science fiction
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movies, right? You can tell it's a robot cause it does simple things, right? Turns out that isn't
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actually the right story. But it's not obvious that isn't the right story, because people assume
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simple rules, simple behavior. And that the sort of the key discovery about the computational
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universe is that isn't true. And that discovery goes very deep and relates to all kinds of things
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that I've spent years and years studying. But, you know, that in the end, the sort of the,
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the what is complexity is, well, you can't easily tell what it's going to do. You could just run the
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rule and see what happens. But you can't just say, Oh, you know, show me the rule. Great.
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And now I know what's going to happen. And, you know, the key phenomenon around that is this thing
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I call computational irreducibility, this fact that in something like rule 30, you might say,
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well, what's it going to do after a million steps? Well, you can run it for a million steps and just
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do what it does to find out. But you can't compress that you can't reduce that and say,
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I'm going to be able to jump ahead and say, this is what it's going to do after a million steps,
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but I don't have to go through anything like that computational effort.
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By the way, has anybody succeeded at that? You had a challenge, a competition.
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Right.
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For predicting the middle column of rule 30.
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Indeed.
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Anybody.
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A number of people have sent things in and sort of people are picking away at it, but it's hard.
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I mean, it's, I've been, I've been actually even proving that the center column of rule 30
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doesn't repeat. That's something I think might be doable. Okay.
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Mathematically proving.
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Yes. And so that's analogous to a similar kind of things like the digits of Pi,
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which are also generated in this very deterministic way. And so a question is how random are the
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digits of Pi? For example, does every, first of all, does the digits of Pi ever repeat?
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Well, we know they don't because it was proved in the 1800s that Pi is not a rational number.
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So that means only rational numbers have digit sequences that repeat.
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So we know the digits of Pi don't repeat. So now the question is, does,
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you know, zero, one, two, three or whatever do all the digits base 10 or base two, or however
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you work it out, do they all occur with equal frequency? Nobody knows. That's far away from
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what can be understood mathematically at this point. And that's, that's kind of, but I'm even
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looking for step one, which is prove that the center column doesn't repeat, and then prove
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other things about it like equally distribution of equal numbers of zeros and ones. And those are
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things which I, you know, I kind of set up this little prize thing, because I thought those were
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not too out of range. Those are things which are within, you know, a modest amount of time,
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it's conceivable that those could be done. They're not, they're not far away from what
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current mathematics might allow. They'll require a bunch of cleverness and hopefully
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some interesting new ideas that, you know, will be useful other places.
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But you started in 1980 with this idea, before I think you realized, you know, this idea of
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programs, you thought that there might be some kind of thermodynamic like randomness, and then
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complexity comes from a clever filter that you kind of like, I don't know, spaghetti or something.
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You filter the randomness and outcomes complexity, which is an interesting intuition. I mean,
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how do we know that's not actually what's happening? So just because you were then able to develop,
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look, you don't need this like incredible randomness, you can just have very simple,
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predictable initial conditions and predictable rules. And then from that emerged complexity,
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still, there might be some systems where it's filtering randomness on the inputs.
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Well, the point is, when you have quotes randomness in the input, that means there's all kinds of
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information in the input. And in a sense, what you get out will be maybe just something close
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to what you put in. Like people are very in dynamical systems theory, sort of big area of
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mathematics that developed from the early 1900s and really got big in the 1980s. You know,
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an example of what people study there a lot. And it's popular version is chaos theory.
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An example of what people study a lot is the shift map, which is basically taking
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2x mod 1 to the fractional part of 2x, which is basically just taking digits in binary
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and shifting them to the left. So at every step, you get to see if you say, how big is this number
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that I got out? Well, the most important digit in that number is whatever ended up at the left
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hand end. But now if you start off from an arbitrary random number, which is quotes randomly
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chosen, so all its digits are random, then when you run that sort of chaos theory shift map,
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all that you get out is just whatever you put in, you just get to see what you what it's not
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obvious that you would excavate all of those digits. And if you're, for example, making a theory,
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I don't know, fluid mechanics, for example, if there was that phenomenon and fluid mechanics,
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then the equations of fluid mechanics can't be right. Because what that would be saying is
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the equations of that, that it matters to the fluid, what happens in the fluid at the level of
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the, you know, millionth digit of the initial conditions, which is far below the points at
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which you're hitting kind of sizes of molecules and things like that. So it's kind of almost
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explaining if that phenomenon is an important thing, it's kind of telling you that the fluid
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dynamics which describes fluids as continuous media and so on isn't really right. But so,
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you know, so this idea that, you know, there's a, it's a tricky thing, because as soon as you put
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randomness in, you have to know, you know, what, how much of what's coming out is what you put in
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versus how much is actually something that's being generated. And what's really nice about
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these systems where you just have very simple initial conditions, and where you get random stuff
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out or seemingly random stuff out, is you don't have that issue, you don't have to argue about
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was there something complicated put in, because plainly obvious there wasn't. Now,
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as a practical matter in doing experiments, the big thing is, if the thing you see is complex
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and reproducible, then it didn't come from just filtering some quotes randomness from the outside
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world. It has to be something that is intrinsically made, because it wouldn't otherwise be, I mean,
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you know, the, the, the, it could be the case that you set things up, and it's always the same each
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time. And you say, well, it's kind of the same, but it's not then it's not random each time,
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because kind of the definition of it being random is it was kind of picked, picked at random each
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time, so to speak. So is it possible to for sure know that our universe does not at the
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fundamental level have randomness? Is it possible to conclusively say there's no randomness at the
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bottom? Well, it's an interesting question. I mean, you know, science, natural science is an
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inductive business, right? You observe a bunch of things and you say, can we fit these together?
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What is our hypothesis for what's going on? The thing that I think I can say fairly definitively
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is at this point, we understand enough about fundamental physics that there is if there was
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sort of an extra dice being thrown, it's something that doesn't need to be there. We can get what
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we see without that. Now, you know, could you add that in as an extra little featureoid?
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You know, without breaking the universe? Probably. But in fact, almost certainly yes.
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But is it necessary for understanding the universe? No. And I think actually from a more
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fundamental point of view, it's, I think I might be able to argue. So one of the things that I've
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been interested in and been pretty surprised that I've had anything sentient to say about
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is the question of why does the universe exist? I didn't think that was a question that I would,
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you know, I thought that was a far out there metaphysical kind of thing. Even the philosophers
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have stayed away from that question for the most part. It's so such a kind of, you know, difficult
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to address question. But I actually think to my great surprise that from our physics project and
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so on, that it is possible to actually address that question and explain why the universe exists.
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And I kind of have a suspicion. I've not thought it through. I kind of have a suspicion that that
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explanation will eventually show you that in no meaningful sense, can there be randomness
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underneath the universe? That is that if there is, it's something that is necessarily irrelevant
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to our perception of the universe. That is that it could be there, but it doesn't matter. Because
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in a sense, we've already, you know, whatever it would do, whatever extra thing it would add,
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is not relevant to our perception of what's going on.
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So why does the universe exist? How does the irrelevance of randomness connect to
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the big why question of the universe? So, okay. So, I mean, why does the universe exist? Well,
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let's see. And is this the only universe we got? It's the only one. About that, I'm pretty sure.
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So you may be, which one, which of these topics is better to enter first? Why does the universe
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exist? And why you think it's the only one that exists?
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Well, I think they're very closely related. Okay. So, I mean, the first thing,
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let's see. I mean, this, why does the universe exist question is built on top of all these things
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that we've been figuring out about fundamental physics. Because if you want to know why the
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universe exists, you kind of have to know what the universe is made of. And I think the, well,
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let me, let me describe a little bit about the why does the universe exist question. So
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the main issue is, let's say you have a model for the universe. And you say, I've got this,
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this program or something, and you run it and you make the universe. Now you say, well, how do
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you act? Why is that program actually running? And people say, you've got this program that
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makes the universe, what computer is it running on? Right? What, what does it mean? What actualizes
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something, you know, two plus two equals four. But that's different from saying there's two,
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a pile of two rocks and another pile of two rocks and so many moves them together and makes four,
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so to speak. And so what is it that kind of turns it from being just this formal thing
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to being something that is actualized? Okay, so there we have to start thinking about, well,
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well, what do we actually know about what's going on in the universe? Well, we are
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observers of this universe. But confusingly enough, we're part of this universe. So in a sense,
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we, what, what, what, if we say, what do we, what do we know about what's going on in the
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universe? Well, what we know is what sort of our consciousness records about what's going on in
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the universe. And consciousness is part of the fabric of the universe. So we're in it.
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Yes, we're in it. And maybe I should, maybe I should start off by saying something about
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the consciousness story. Because that that's, maybe we should begin even before that at the
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very base layer of the Wolfram physics project. Maybe you can give a broad overview once again,
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really quick about this hypergraph model. Yes. And also, what is it a year and a half ago,
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since you've brought this project to the world, what is the status update? Where what are all the
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beautiful ideas you have come across? What are the interesting things you can mention?
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It's, I mean, it's a, it's a frigging Cambrian explosion. I mean, it's, it's crazy. I mean,
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there are all these things which I've kind of wondered about for years. And suddenly,
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there's actually a way to think about them. And I really did not see, I mean, the real strength
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of what's happened, I absolutely did not see coming. And the real strength of it is, we've
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got this model for physics, but it turns out it's a foundational kind of model that's a different
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kind of computation like model that I'm kind of calling the sort of multi computational model.
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And that, that kind of model is applicable not only to physics, but also to lots of other
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kinds of things. And one reason that's extremely powerful is because physics has been very successful.
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So we know a lot based on what we figured out in physics. And if we know that the same model
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governs physics and governs, I don't know, economics, linguistics, immunology, whatever,
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we know that the same kind of model governs those things. We can start using things that we've
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successfully discovered in physics and applying those intuitions in all these other areas. And
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that's, that's pretty exciting. And, and, and very surprising to me. And in fact, it's kind of like
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in the original story of sort of you go and you explain why is there complexity in the natural
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world, then you realize, well, there's all this complexity, there's all this computational
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irreducibility, you know, there's a lot we can't know about what's going to happen. It's kind of
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it's kind of a very confusing thing for people who say, you know, science has nailed everything
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down, we're going to, you know, based on science, we can know everything. Well, actually, there's
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this computational irreducibility thing, right in the middle of that, thrown up by science, so to
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00:20:22.640
speak. And then the question is, well, given computational irreducibility, how can we actually
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figure out anything about what happens in the world? Why aren't we, why are we able to predict
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00:20:31.600
anything? Why are we able to sort of operate in the world? And the answer is that we sort of live
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00:20:35.440
in these slices of computational reusability that exists in this kind of ocean of computational
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irreducibility. And it turns out that seems that it's a very fundamental feature of the kind of
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model that seems to operate in physics, and perhaps in the bottom of these other areas,
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00:20:52.800
that there are these particular slices of computational reusability that are relevant
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00:20:57.680
to us. And those are the things that both allow us to operate in the world, and not just have
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and not just have everything be completely unpredictable. But there are also things that
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potentially give us what amount to sort of physics like laws in all these other areas. So
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00:21:13.120
that's been sort of an exciting thing. But I would say that in general, for our project,
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00:21:18.320
it's been going spectacularly well. I mean, it's very, honestly, it wasn't something I expected
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00:21:24.560
to happen in my lifetime. I mean, it's something where it's, and in fact, one of the things about
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00:21:31.920
it, some of the things that we've discovered are things where I was pretty sure that wasn't how
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00:21:36.880
things worked. And turns out I'm wrong. And, you know, in a major area in mathematics, I'd be
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00:21:43.600
realizing that I've something I've long believed, we can talk about it later, that just really
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00:21:49.840
isn't right. But I think that the thing that, so what's happened with the physics project,
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00:21:56.720
I mean, you know, it's a can explain a little bit about how the how the model works. But basically,
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00:22:02.640
we can maybe ask you the following question. So it's easy through words describe how cellular
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00:22:08.800
automata works. You've explained this. And it's the fundamental mechanism by which you in your
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00:22:16.800
book, and you kind of science explored the idea of complexity and how to do science in this world
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00:22:22.480
of island reducible islands and irreducible generally irreducibility. Okay, so how does
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00:22:29.760
the model of hypergraphs differ from cellular automata? And how does the idea of multi computation
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00:22:36.480
differ? Like maybe that's a way to describe it. Right. We're, we're, you know, right. This is a,
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00:22:41.600
you know, my life is like all of our lives, something of a story of computational irreducibility.
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00:22:46.560
Yes. And, you know, it's been going for a few years now. So it's always a challenge to kind of
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find these appropriate pockets of reducibility. But let me see what I can do. So, so I mean,
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first of all, let's, let's talk about physics. First of all, and, you know, a key observation
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00:23:04.400
that one of the starting point of our physics project is things about what is space? What is
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00:23:10.160
the universe made of? And, you know, ever since Euclid, people just sort of say space is just this
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thing where you can put things at any position you want. And they're just points and they're just
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00:23:20.160
geometrical things that you can just arbitrarily put at different, different coordinate positions.
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00:23:25.440
So the first thing in our physics project is the idea that space is made of something,
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00:23:30.400
just like water is made of molecules, space is made of kind of atoms of space. And the only
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00:23:36.000
thing we can say about these atoms of space is they have some identity. There's a, there's a,
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00:23:40.000
there is, it's this atom as opposed to this atom. And, you know, you could give them, if you were a
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00:23:44.400
computer person, you give them UUIDs or something. But that's all there is to say about them,
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00:23:51.760
so to speak. And then all we know about these atoms of space is how they relate to each other.
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00:23:59.840
So we say these three atoms of space are associated with each other in some relation. So you can
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00:24:06.400
think about that as, you know, what atom of space is friends with what other atom of space?
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00:24:11.920
You can build this essentially friend network of the atoms of space. And the sort of starting
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00:24:17.280
point of our physics project is that's what our universe is. It's a giant friend network of the
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00:24:21.840
atoms of space. And so how can that possibly represent our universe? Well, it's like in
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00:24:29.360
something like water, you know, there are molecules bouncing around, but on a large scale,
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00:24:34.000
that, you know, that produces fluid flow and we have fluid vortices and we have all of these
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00:24:38.560
phenomena that are sort of the emergent phenomena from that underlying kind of collection of
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00:24:44.480
molecules bouncing around. And by the way, it's important that that collection of molecules
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00:24:48.160
bouncing around have this phenomenon of computational irreducibility. That's actually what
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00:24:52.640
leads to the second law of thermodynamics, among other things. And that leads to the sort of randomness
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00:24:58.160
of the underlying behavior, which is what gives you something which on a large scale seems like
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00:25:03.520
it's a smooth continuous type of thing. And so, okay, so first thing is space is made of something,
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00:25:10.960
it's made of all these atoms of space connected together in this network. And then everything
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00:25:16.560
that we experience is sort of features of the of that structure of space. So, you know, when we
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00:25:22.160
have an electron or something or a photon, it's some kind of tangle in the structure of space,
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00:25:27.280
much like kind of a vortex and a fluid would be just this thing that is, you know, it can actually
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00:25:32.880
the vortex can move around, it can involve different molecules in the fluid, but the vortex
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00:25:37.680
still stays there. And if you zoom out enough, the vortex looks like an atom itself, like a basic
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00:25:42.800
element. So there's the levels of abstraction. If you squint and kind of blur things out,
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00:25:49.680
it looks like at every level of abstraction, you can define what is a basic individual entity.
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00:25:55.760
Yes, but you know, in this model, there's a bottom level, you know, there's an elementary
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length, maybe 10 to the minus 100 meters, let's say, which is really small, you know,
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proton is 10 to the minus 15 meters, the smallest we've ever been able to sort of
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see with the particle accelerators around 10 to the minus 21 meters. So, you know, if we don't
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know precisely what the correct scale is, but it's perhaps over the order of 10 to the minus 100
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meters, so it's pretty small. And but that's the end, that's what things are made of.
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00:26:26.880
What's your intuition where the 10 to the minus 100 comes from? What's your intuition about this
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00:26:32.400
scale? Well, okay, so there's a calculation which I consider to be somewhat rickety, okay,
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00:26:37.840
which has to do with comparing. So, so there are various fundamental constants, there's the speed
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00:26:43.280
of light, the speed of light, once you know the elementary time, the speed of light is tells you
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00:26:48.960
the conversion from the elementary time to the elementary length. Then there's the question of
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00:26:53.120
how do you convert to the elementary energy? And how do you convert to between other things? And
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00:26:58.880
the various constants we know, we know the speed of light, we know the gravitational constant,
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00:27:03.360
we know Planck's constant and quantum mechanics, those are the three important ones.
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00:27:07.600
And we actually know some other things, we know things like the size of the universe,
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00:27:11.680
the Hubble constant, things like that. And essentially, this calculation of the elementary
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00:27:16.960
length comes from looking at these sort of combination of those, okay, so the most obvious
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00:27:22.720
thing, people have sort of assumed that quantum gravity happens at this thing, the Planck scale,
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00:27:27.120
10 to the minus 34 meters, which is the sort of the combination of Planck's constant and the
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00:27:32.640
gravitational constant and the speed of light that gives you that kind of length.
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00:27:37.280
Turns out in our model, there is an additional parameter, which is essentially the number of
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00:27:42.960
simultaneous threads of execution of the universe, which is essentially the number of sort of independent
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00:27:48.160
quantum processes that are going on. And that number, let's see if I remember that number,
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00:27:53.280
that number is 10 to the 170, I think, and so it's a big number. But that number then connects,
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00:28:01.200
you know, sort of modifies what you might think from all these Planck units to give you the
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things we're giving. And there's been sort of a mystery, actually, in the more technical physics
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00:28:12.000
thing, that the Planck mass, the Planck energy, Planck energy is actually surprisingly big.
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00:28:18.960
The Planck length is tiny, 10 to the minus 34 meters, that Planck time 10 to the minus
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00:28:23.200
43 meters, I think, seconds, I think. But the Planck energy is like the energy of a
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00:28:30.880
lightning strike, which is pretty weird. In our models, the actual elementary energy is that
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00:28:37.360
divided by the number of sort of simultaneous quantum threads, and it ends up being really small,
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00:28:42.160
too. And that sort of explains that mystery that's been around for a while about how Planck units
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00:28:48.080
work. But whether that precise estimate is right, we don't know yet. I mean, that's one of the things
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00:28:54.640
that's sort of been a thing we've been pretty interested in, is how do you see through, you
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00:28:59.360
know, how do you make a gravitational microscope that can kind of see through to the atoms of
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00:29:04.880
space? You know, how do you get in fluid flow, for example, if you go to hypersonic flow or
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00:29:10.000
something, you know, you've got a Mach 20, you know, space plane or something, it really matters
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00:29:14.720
that there are individual molecules hitting the space plane, not a continuous fluid. The question
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00:29:20.080
is, what is the analogous kind of, what is the analog of hypersonic flow for our, for things about
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00:29:27.200
the structure of spacetime? And it looks like a rapidly rotating black hole right at the sort of
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00:29:34.000
critical rotation rate is, it looks as if that's a case where essentially, the structure of spacetime
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00:29:42.640
is just about to fall apart. And you may be able to kind of see the evidence of sort of discrete
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00:29:50.880
elements, you know, you may be able to kind of see there, the sort of gravitational microscope
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00:29:55.760
of actually seeing these discrete elements of space. And there may be some effect in, for example,
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00:30:01.200
gravitational waves produced by rapidly rotating black hole, that in which one could actually see
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00:30:07.360
some phenomenon where one can say, yes, these don't come out the way one would expect,
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00:30:12.160
based on having a continuous structure of spacetime, that it is something where you can kind of see
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00:30:17.680
through to the discrete structure. We don't know that yet. So can you maybe elaborate a little
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00:30:23.120
bit deeper how a microscope that can see to 10 to the minus 100, how rotating black holes and
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00:30:32.160
presumably the detailed accurate detection of gravitational waves from black holes can
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00:30:40.000
reveal the discreetness of space? Okay, first thing is, what is a black hole? Actually, we need
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00:30:45.920
to go a little bit further in the story of what spacetime is, because I explained a little bit
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00:30:49.360
about what space is, but I didn't talk about what time is. And that's sort of important in
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00:30:54.320
understanding spacetime, so to speak. And your sense is both space and time in the story are
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00:30:59.280
discrete? Absolutely. Absolutely. But it's a complicated story and needless to say.
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00:31:05.360
Well, it's simple at the bottom. It's very simple at the bottom. It's very, in the end,
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00:31:11.520
it's simple but deeply abstract. And something that is simple in conception,
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00:31:18.320
but kind of wrapping one's head around what's going on is pretty hard.
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00:31:23.120
But so first of all, we have this, so I've described these kind of atoms of space and
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00:31:27.920
their connections. You can think about these things as a hypergraph. A graph is just,
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00:31:32.400
you connect nodes to nodes, but a hypergraph, you can have sort of not just friends,
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00:31:38.880
individual friends to friends, but you can have these triplets of friends or whatever else.
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00:31:43.200
And so we're just saying, and that's just the relations between atoms of space
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00:31:48.800
are the hyper edges of the hypergraph. And so we got some big collection of these atoms of
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00:31:53.600
space, maybe 10 to the 400 or something in our universe. And that's the structure of space.
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00:32:00.000
That's an every feature of what we experience in the world is a feature of that hypergraph,
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00:32:07.120
that spatial hypergraph. So then the question is, well, what does that spatial hypergraph do?
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00:32:12.240
Well, the idea is that there are rules that update that spatial hypergraph. And in a cellular
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00:32:18.640
automaton, you've just got this line of cells, and you just say at every step, at every time step,
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00:32:23.680
you've got fixed time steps, fixed array of cells. At every step, every cell gets updated
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00:32:29.200
according to a certain rule. And that's kind of the way it works. Now, in this hypergraph,
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00:32:34.960
it's sort of vaguely the same kind of thing. We say every time you see a little piece of
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00:32:39.760
hypergraph that looks like this, update it to one that looks like this. So it's just keep
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00:32:45.200
rewriting this hypergraph. Every time you see something that looks like that, anywhere in the
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00:32:49.200
universe, it gets rewritten. Now, one thing that's tricky about that, which we'll come to is this
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00:32:54.240
multi computational idea, which has to do with, you're not saying, in some kind of lock step way,
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00:33:00.320
do this one, then this one, then this one, it's just whenever you see one you can do,
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00:33:04.640
you can go ahead and do it. And that leads one not to have a single thread of time in the universe.
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00:33:11.120
Because if you knew which one to do, you would just say, okay, we do this one,
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00:33:14.960
then we do this one, then we do this one. But if you say just do whichever one you feel like,
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00:33:19.040
you end up with these multiple threads of time, these kind of multiple histories of the universe,
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00:33:23.040
depending on which order you happen to do the things you could do in.
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00:33:27.120
So it's fundamentally asynchronous and parallel?
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00:33:29.760
Yes. Yes. Which is very uncomfortable for the human brain that seeks for things to be sequential
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00:33:36.240
and synchronous. Right. Well, I think that this is part of the story of consciousness,
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00:33:42.560
is I think the key aspect of consciousness that is important for sort of parsing the universe
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00:33:48.480
is this point that we have a single thread of experience. We have a memory of what happened
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00:33:53.680
in the past, we can say something, predict something about the future, but there's a
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00:33:57.440
single thread of experience. And it's not obvious it should work that way. I mean, we've got 100
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00:34:00.960
billion neurons in our brains, and they're all firing in all kinds of different ways. But yet,
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00:34:05.520
our experience is that there is the single thread of time that goes along. And I think that,
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00:34:13.840
one of the things I've kind of realized with a lot more clarity in the last year,
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00:34:17.360
is the fact that we conclude that the universe has the laws it has is a consequence of the fact
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00:34:24.800
that we have consciousness the way we have consciousness. And so the fact, so I mean,
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00:34:30.240
just to go on with kind of the basic setup, it's, so we got this spatial hypergraph,
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00:34:35.360
it's got all these atoms of space, they're getting these little clumps of atoms of space
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00:34:40.080
are getting turned into other clumps of atoms of space, and that's happening everywhere in the
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00:34:42.800
universe all the time. And so one thing that's a little bit weird is there's nothing permanent
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00:34:47.520
in the universe. The universe is getting rewritten everywhere all the time. And if it wasn't getting
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00:34:51.920
rewritten, space wouldn't be knitted together. That is, space would just fall apart. There wouldn't
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00:34:56.720
be any way in which we could say this part of space is next to this part of space. One of the
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00:35:01.760
things that people were confused about back in antiquity, the ancient Greek philosophers and
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00:35:08.080
so on is how does motion work? How can it be the case that you can take a thing that we can walk
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00:35:13.680
around? And it's still us when we walked a foot forward, so to speak. And in a sense with our
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00:35:19.840
models, that's again, a question, because it's a different set of atoms of space when we, you know,
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00:35:25.680
when I move my hand, it's moving into a different set of atoms of space. It's having to be recreated,
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00:35:31.520
it's not the thing itself is not there, it's being continuously recreated all the time. Now,
link |
00:35:37.040
it's a little bit like waves in an ocean, you know, vortices and fluid, which again, the actual
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00:35:41.920
molecules that exist in those are not what define the identity of the thing. And but it's a little
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00:35:48.160
bit, you know, this idea that there can be pure motion, that it can, that it is even possible
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00:35:54.320
for an object to just move around in the universe and not change. It's not self evident that such
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00:36:00.240
a thing should be possible. And that is part of our perception of the universe is that we
link |
00:36:06.160
parse those aspects of the universe where things like pure motion are possible. Now, pure motion,
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00:36:11.360
even in general relativity, the theory of gravity, pure motion is a little bit of a complicated thing.
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00:36:16.640
I mean, if you imagine your average, you know, teacup or something approaching a black hole,
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00:36:21.760
it is deformed and distorted by the structure of space time. And to say, you know, is it really
link |
00:36:26.800
pure motion? Is it that same teacup that's the same shape? Well, it's a bit of a complicated story.
link |
00:36:31.920
And this is a more extreme version of that. So, so anyway, the thing that that's happening is
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00:36:37.760
we got space, we've got this notion of time. So time is this kind of this rewriting of the
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00:36:44.000
hypergraph. And one of the things that's important about that time is this sort of computational
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00:36:48.800
irreducible process. There's something, you know, time is not something where it's kind of the
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00:36:53.840
mathematical view of time tends to be time is just a coordinate, we can, you know, slide a slider,
link |
00:37:00.320
turn a knob, and we'll change the time that we've got in this equation. But in this picture of time,
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00:37:06.800
that's not how it works at all. Time is this inexorable, irreducible kind of set of computations
link |
00:37:12.960
that go on that go from where we are now to the future. But so so the thing, and one of the things
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00:37:18.880
that is again, something one sort of has to break out of is your average trained physicist like me
link |
00:37:24.880
says, you know, space and time are the same kind of thing. They're related by, you know, the prank
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00:37:29.680
array group and Lawrence transformations and relativity and all these kinds of things. And,
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00:37:34.400
you know, space and time, you know, there are all these kind of sort of folk stories you can tell
link |
00:37:39.280
about why space and time are the same kind of thing. In this model, they're fundamentally not
link |
00:37:43.600
the same kind of thing. Space is this kind of sort of connections between these atoms of space.
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00:37:49.360
Time is this computational process. So the thing that the first sort of surprising thing
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00:37:54.720
is, well, it turns out you get relativity anyway. And the reason that happens that a few bits and
link |
00:38:00.160
pieces here, which one has to understand, but but the fundamental point is, if you are an observer
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00:38:06.560
embedded in the system, that a part of this whole story of things getting updated in this way and
link |
00:38:12.720
that, there are there's sort of a limit to what you can tell about what's going on. And really,
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00:38:17.760
in the end, the only thing you can tell is what are the causal relationships between events. So an
link |
00:38:23.200
event in this sort of an elementary event is a little piece of hypergraph got rewritten. And
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00:38:30.160
that means a few hyper edges of the hypergraph were consumed by the event. And you produce some
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00:38:35.520
other hyper edges. And that's an elementary event. And so then the question is, what we can tell
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00:38:42.000
is kind of what the network of causal relationships between elementary events is.
link |
00:38:47.120
That's the ultimate thing, the causal graph of the universe. And it turns out that, well, there's
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00:38:52.800
this property of causal invariance that is true of a bunch of these models. And I think is inevitably
link |
00:38:58.800
true for a variety of reasons. That makes it be the case that it doesn't matter kind of if you are
link |
00:39:07.200
sort of saying, well, I've got this hypergraph, and I can rewrite this piece here and this piece
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00:39:11.040
here. And I do them all in different orders. When you construct the causal graph for each of those
link |
00:39:15.680
orders, that you choose to do things in, you'll end up with the same causal graph. And so that's
link |
00:39:22.560
essentially why, well, that's in the end, why relativity works. It's why our perception of
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00:39:28.960
space and time is as having this kind of connection that relativity says they should have. And that's
link |
00:39:35.600
kind of how that works. I think I'm missing a little piece. If we can go there again, you said
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00:39:41.760
the fact that the observer is embedded in this hypergraph, what's missing? What is the observer
link |
00:39:48.400
not able to state about this universe of space and time? If you look from the outside, you can say,
link |
00:39:55.440
oh, I see this particular place was updated, and then this one was updated, and I'm seeing
link |
00:40:04.880
which order things were updated in. But the observer embedded in the universe doesn't know
link |
00:40:09.360
which order things were updated in, because until they've been updated, they have no idea what else
link |
00:40:14.000
happened. So the only thing they know is the set of causal relationships. Let me give an extreme
link |
00:40:19.360
example. Let's imagine that the universe is a Turing machine. Turing machines have just this one
link |
00:40:25.040
update head, which does something, and otherwise the Turing machine just does nothing. And the
link |
00:40:30.800
Turing machine works by having this head move around and do its updating just where the head
link |
00:40:35.920
happens to be. The question is, could the universe be a Turing machine? Could the universe just have
link |
00:40:41.040
a single updating head that's just zipping around all over the place? You say, that's crazy, because
link |
00:40:46.320
I'm talking to you, you seem to be updating, I'm updating, etc. But the thing is, there's no way
link |
00:40:51.760
to know that, because if there was just this head moving around, it's like, okay, it updates me,
link |
00:40:56.640
but you're completely frozen at that point. Until the head has come over and updated you,
link |
00:41:01.200
you have no idea what happened to me. And so if you unravel that argument, you realize the only
link |
00:41:06.400
thing we actually can tell is what the network of causal relationships between the things that
link |
00:41:12.320
happened were. We don't get to know from some sort of outside sort of God's eye view of the thing.
link |
00:41:18.800
We don't get to know what sort of from the outside what happened. We only get to know
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00:41:25.280
sort of what the set of relationships between the things that happened actually were.
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00:41:29.680
Yeah, but if I somehow record like a trace of this, I guess we'll be called multi computation.
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00:41:36.880
Can't I then look back? When you record the trace some you place throughout the universe,
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00:41:45.040
like throughout, like a log that records in my own pocket of in this hypergraph, can't I
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00:41:52.400
like realizing that I'm getting an outdated picture? Can't I record?
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00:41:58.960
See, the problem is, and this is where things start getting very entangled in terms of what
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00:42:04.720
one understands. The problem is that any such recording device is itself part of the universe.
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00:42:11.680
So you don't get to say, you never get to say, let's go outside the universe and go do this.
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00:42:16.720
And that's why, I mean, lots of the features of this model and the way things work end up
link |
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being a result of that. So, but what I guess from on a human level, what is
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00:42:28.880
the cost you're paying? What are you missing from not getting an updated picture all the time?
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00:42:34.160
Okay, I got, I understand what you're just saying. Yeah, yeah, right.
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00:42:36.320
But like what, like how does consciousness emerge from that? Like how, like, what are the
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00:42:42.880
limitations of that observer? I understand you're getting a delay. Well, there's a, okay,
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00:42:47.280
there's, there's, there's a bunch of limitations of the observer, I think. Maybe just explain
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something about quantum mechanics, because that maybe is a, is an extreme version of some of
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these issues, which helps to kind of motivate why one should sort of think things through a little
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bit more carefully. So one feature of the, of this, okay, so in standard physics, like high
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school physics, you learn, you know, the equations of motion for a ball. And the, the, you know,
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it says, you throw the ball this angle, this velocity, things will move in this way. And
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there's a definite answer, right? The story, the key story of quantum mechanics is there
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00:43:22.960
aren't definite answers to where does the ball go? There's kind of this whole sort of bundle of
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possible paths. And all we say we know from quantum mechanics is certain probabilities
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00:43:33.680
for where the ball will end up. Okay. So that's kind of the, the core idea of quantum mechanics.
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00:43:38.320
So in our models, you, quantum mechanics is not some kind of plug in add on type thing.
link |
00:43:44.320
You absolutely cannot get away from quantum mechanics, because as you think about updating
link |
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this hypergraph, there isn't just one sequence of things, one definite sequence of things that
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can happen. There are all these different possible update sequences that can occur. You could do
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00:43:57.520
this, you know, piece of the hypergraph now, and then this one later, and et cetera, et cetera,
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et cetera. All those different paths of history correspond to these quantum, quantum paths and
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quantum mechanics, these different possible quantum histories. And one of the things that's
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kind of surprising about it is they, they branch, you know, there can be a certain state of the
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universe, and it could do this or it could do that, but they can also merge. There can be two
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states of the universe, which their next state, the next state they produce is the same for both
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of them. And that process of branching and merging is kind of critical. And the idea that they can
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be merging is critical and somewhat nontrivial for these hypergraphs, because there's a whole
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graph isomorphism story, and there's a whole very elaborate set of mathematics.
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00:44:40.160
That's where the causal invariance comes in.
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00:44:42.000
Yes, among other things. Right. Yes. But so then what happens is that what one's seeing,
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okay, so we've got this thing, it's branching, it's merging, et cetera, et cetera, et cetera.
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Okay, so now the question is, how do we perceive that? What, you know, how do we,
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do we, why don't we notice that the universe is branching and merging? Why, you know, why is it
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the case that we just think a definite set of things happen? Well, the answer is we are embedded
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in that universe, and our brains are branching and merging too. And so what quantum mechanics
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becomes a story of is how does a branching brain perceive a branching universe? And the key thing
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is, as soon as you say, I think definite things happen in the universe, that means you are essentially
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conflating lots of different parts of history. You're saying, actually, as far as I'm concerned,
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because I'm convinced that definite things happen in the universe, all these parts of history must
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be equivalent. Now, it's not obvious that that would be a consistent thing to do. It might be,
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you say, all these parts of history are equivalent, but by golly, moments later, that would be a
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completely inconsistent point of view. Everything would have, you know, gone to hell in different
link |
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ways. The fact that that doesn't happen is, well, that's a consequence of this causal
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00:45:56.000
invariance thing. But that's, and the fact that that does happen a little bit is what causes little
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quantum effects. And that if that didn't happen at all, there wouldn't be anything that sort of
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is like quantum mechanics. It would be quantum mechanics is kind of like in this,
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in this kind of this bundle of paths. It's a little bit like what happens in statistical
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mechanics and fluid mechanics, whatever, that most of the time, you just see this continuous fluid,
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you just see the world just progressing in this kind of way that's like this continuous fluid.
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But every so often, if you look at the exact right experiment, you can start seeing, well,
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actually, it's made of these molecules where they might go that way, or they might go this way.
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And that's kind of quantum effects. And so that's so the this kind of idea of where we're sort of
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embedded in the universe, this branching brain is perceiving this branching universe. And that ends
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up being sort of a story of quantum mechanics. That's, that's part of the whole picture of
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what's going on. But I think, I mean, to come back to sort of where does conscious, what is,
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what is the story of consciousness? So in the universe, we've got, you know, whatever it is,
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10 to the 400 atoms of space, they're all doing these complicated things. It's all a big, complicated,
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irreducible computation. The question is, what do we perceive from all of that? And the answer is that
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we are, we are parsing the universe in a particular way. Let me again, go back to the gas molecules
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analogy. You know, in the gas in this room, there are molecules bouncing around all kinds of complicated
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patterns. But we don't care. All we notice is there's, you know, the gas laws are satisfied.
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Maybe there's some fluid dynamics. These are kind of features of that assembly of molecules that we
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notice. And then lots of details we don't notice. When you say we, do you mean the tools of physics,
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or do you mean literally the human brain and its perception system?
link |
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Well, okay. So the human brain is where it starts, but we built a bunch of instruments to do a bit
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better than the human brain. But they still have many of the same kinds of ideas, you know, their
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cameras and their pressure sensors and these kinds of things. They're not, you know, at this point,
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we don't know how to make fundamentally qualitatively different sensory devices.
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00:48:07.360
Right. So it's always just an extension of the conscious experience or our sensory experience.
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Sensory experience, but sensory experience that's somehow intricately tied to consciousness.
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00:48:20.320
Right. Well, so, so one question is when we are looking at all these molecules in the gas,
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and there might be 10 to 20 molecules in some little, little box or something, it's like,
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what, what do we notice about those molecules? So one thing that we can say is we don't notice
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that much. We are, you know, we are computationally bounded observers. We can't go in and say,
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okay, I'm the 10 to 20th molecules, and I know that I can sort of decrypt their motions and I
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can figure out this and that. It's like, I'm just going to say what's the average density of molecules.
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00:48:51.840
And so one key feature of us is that we are computationally bounded. And that when you
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are looking at a universe, which is full of computation and doing huge amounts of computation,
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00:49:03.040
but we are computationally bounded, there's only certain things about that universe that
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we're going to be sensitive to. We're not going to be, you know, figuring out what all the atoms
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of space are doing, because we're just computationally bounded observers, and we are only sampling
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00:49:18.320
these, these small set of features. So I think the two defining features of consciousness that,
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and I, you know, I would say that the sort of the preamble to this is for years, you know,
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because I've talked about sort of computation and fundamental features of physics and science,
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people ask me, so what about consciousness? And I, for years, I've said, I have nothing to say
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about consciousness. And, you know, I've kind of told this story, you know, you talk about
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00:49:43.760
intelligence, you talk about life. These are both features where you say, what's the abstract
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00:49:49.280
definition of life, we don't really know the abstract definition, we know the one for life on
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00:49:52.720
earth, it's got RNA, it's got cell membranes, it's got all this kind of stuff. Similarly,
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for intelligence, we know the human definition of intelligence, but what is intelligence abstractly,
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00:50:02.480
we don't really know. And so what I've long believed is that sort of the abstract definition
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of intelligence is just computational sophistication. That is, that as soon as you can be computationally
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sophisticated, that's kind of the abstract version, the generalized version of intelligence.
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00:50:19.680
So then the question is, what about consciousness? And what I sort of realized is that consciousness
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00:50:24.400
is actually a step down from intelligence. That is, that you might think, oh, you know,
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consciousness is the top of the pile. But actually, I don't think it is. I think that there's this
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notion of kind of computational sophistication, which is the generalized intelligence. But
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consciousness has two limitations, I think. One of them is computational boundedness. That is,
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that we're only perceiving a sort of computationally bounded view of the universe. And the other is
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00:50:53.200
this idea of a single thread of time. That is, that we, and in fact, we know neurophysiologically,
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our brains go to some trouble to give us this one thread of attention, so to speak. And it
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isn't the case that, you know, in all the neurons in our brains, that, that in at least in our conscious,
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note the, you know, the correspondence of language in our conscious experience,
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we just have the single thread of attention, single thread of, of perception. And, you know,
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maybe there's something unconscious that's bubbling around. That's the kind of almost the quantum
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version of what's happening in our brain, so to speak. We've got the, the classical flow of what
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we are mostly thinking about, so to speak. But there's this kind of bubbling around of other
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paths that is all those other neurons that didn't make it to be part of our sort of conscious stream
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of experience. So in that sense, intelligence as computational sophistication is much broader
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00:51:45.360
than, than the, the computational constraints, which consciousness operates under and also
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00:51:54.080
the sequential, like the sequential thing, like the notion of time. That's, that's kind of interesting.
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00:51:59.840
But then the, the follow up question is like, okay, starting to get a sense of what is intelligence
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00:52:05.040
and how does that connect to our human brain? Because you're saying
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00:52:10.400
intelligence is almost like a fabric, like what we like plug into it or something. Like,
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00:52:15.040
yeah, I think, you know, people, our consciousness plugs into it.
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00:52:18.320
Yeah. I mean, the intelligence, I think the core, I mean, you know, intelligence at some
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00:52:23.520
level is just a word, but we're asking, you know, what is the, the notion of intelligence
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00:52:28.480
as we generalize it beyond the bounds of humans, beyond the bounds of even the AIs that we humans
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00:52:33.600
have built and so on, you know, what, what is intelligence? You know, is the weather, you know,
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00:52:39.120
people say the weather has a mind of its own. What does that mean? You know, can the weather be
link |
00:52:42.640
intelligent? Yeah. What does agency have to do with intelligence here? So is intelligence just
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00:52:48.320
like your conception of computation? Just intelligence is a, is the capacity to perform
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00:52:54.640
computation in the sea of? Yeah, I think so. I mean, I think that's right. And I think that,
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00:52:59.840
you know, this question of, of, is it for a purpose? Okay. That quickly degenerates into
link |
00:53:06.560
a horrible philosophical mess. Because, you know, whenever you say, did the weather do that for a
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00:53:11.920
purpose? Yeah. Right? Well, yes, it did. It was trying to move a bunch of hot air from the equator
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00:53:17.200
to the poles or something. That's its purpose. But why? Because I seem to be equally as dumb
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00:53:23.200
today as I was yesterday. So there's some persistence, like a consistency over time
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00:53:29.600
that the intelligence I plugged into. So like, what's, it seems like there's a hard constraint.
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00:53:36.320
Well, that's not. Between the amount of computation I can perform in my consciousness.
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00:53:40.720
Like they seem to be really closely connected somehow. Well, I think the point is that the
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00:53:45.280
thing that gives you kind of the ability to have kind of conscious intelligence,
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00:53:52.880
you can have kind of this. Okay. So, so one thing is we don't know intelligence is other
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00:53:58.320
than the ones that are very much like us. Yes. Right. And the ones that are very much like us,
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I think have this feature of single thread of time bounded, you know, computationally bounded.
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00:54:09.280
Now, that, but you also need computational sophistication. Having a single thread of
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00:54:14.480
time and being computationally bounded, you could just be a clock going tick tock, you know,
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00:54:19.760
that would satisfy those conditions. But the fact that we have this sort of irreducible,
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00:54:26.880
you know, computational ability, that's, that's an important feature. That's, that's the sort of
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the bedrock on which we can construct the things we construct. Now, the fact that we have this
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00:54:38.560
experience of the world that has the single thread of time and computational boundedness,
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00:54:43.520
the thing that I sort of realized is it's that that causes us to deduce from this irreducible
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00:54:50.880
mess of what's going on in the physical world, the laws of physics that we think exist. So,
link |
00:54:56.880
in other words, if we say, why do we believe that there is, you know, a continuous space,
link |
00:55:03.440
let's say, why do we believe that gravity works the way it does? Well, in principle,
link |
00:55:08.960
we could be kind of parsing details of the universe that were, you know, that, okay,
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00:55:15.840
the analogy is, again, with the statistical mechanics and molecules in a box, we could be
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00:55:23.600
sensitive to every little detail of the swirling around of those molecules. And we could say,
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00:55:27.760
what really matters is the, you know, the wiggle effect. Yes. That is, you know, that is something
link |
00:55:33.440
that we humans just never notice because it's some weird thing that happens when there are 15
link |
00:55:38.160
collisions of air molecules and this happens and that happens. We just see the pure motion of a
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00:55:43.360
ball moving about. Right. Why do we see that? Right. And the point is that, that what seems
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00:55:49.840
to be the case is that the things that if we say, given this sort of hypergraph that's updating and
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00:55:55.840
all the details about all the sort of, sort of atoms of space and what they do, and we say,
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00:56:00.640
how do we slice that to what we can be sensitive to? What seems to be the case is that as soon as
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00:56:06.080
we assume, you know, computational boundedness, single thread of time, that leads us to general
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00:56:12.080
relativity. In other words, we can't avoid that. That that's the way that we, we will parse the
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universe. Given those constraints, we parse the universe according to those particular,
link |
00:56:22.800
in such a way that we say the aggregate reducible, sort of, pocket of computational
link |
00:56:30.400
reducibility that we slice out of this kind of whole computationally irreducible ocean of behavior
link |
00:56:37.520
is just this one that corresponds to general relativity. Yeah, but we don't perceive general
link |
00:56:41.280
relativity. Well, we do if we do fancy experiments. So you're saying, so perceive really does mean
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00:56:47.520
the fault. We drop something. That's a great example of general relativity in action. No,
link |
00:56:52.160
but like, what's the difference between that and Newtonian mechanics? I mean,
link |
00:56:55.520
Oh, it doesn't. This is, when I say general relativity, that's even gravity, the Uber theory,
link |
00:57:00.880
so to speak. I mean, Newtonian gravity is just the approximation that we can make,
link |
00:57:05.920
you know, on the earth and things like that. So, so this is, you know, the phenomenon of gravity
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00:57:11.600
is one that is a consequence of, you know, we would perceive something very different from
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00:57:17.040
gravity. So, so the way to understand that is when we think about, okay, so we make up reference
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00:57:25.440
frames with which we parse what's happening in space and time. So in other words, one of the,
link |
00:57:30.880
one of the things that we do is we say, as time progresses, everywhere in space is something
link |
00:57:39.600
happens at a particular time. And then we go to the next time, and we say, this is what space is
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00:57:43.920
like at the next time, this is what space is like at the next time. That's, it's the reason we are
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00:57:49.680
used to doing that is because, you know, when we look around, we might see, you know, 10, 100 meters
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00:57:55.840
away. The time it takes light to travel that distance is really short compared to the time it
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00:58:01.840
takes our brains to know what happened. So as far as our brains are concerned, we are parsing the
link |
00:58:07.360
universe in this, there is a moment in time, it's all of space, there's a moment in time, it's all
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00:58:12.480
of space. You know, if we were the size of planets or something, we would have a different perception
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00:58:17.200
because the speed of light would be much more important to us. We wouldn't have this perception
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00:58:21.680
that things happen progressively in time, everywhere in space. And so that's an important
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00:58:27.840
kind of constraint. And the reason that we kind of parse the universe in the way that causes us to
link |
00:58:33.280
say gravity works the way it does, is because we're doing things like deciding that we can say the
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00:58:39.520
universe exists, space has a definite structure. There is a moment in time, space has this definite
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00:58:45.680
structure, we move to the next moment in time, space has another structure. That kind of setup
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00:58:50.720
is what lets us kind of deduce kind of what to parse the universe in such a way that we say
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00:58:57.600
gravity works the way it does. So that kind of reference frame is that the illusion of that
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00:59:02.960
is that you're saying that somehow useful for consciousness. That's what consciousness does,
link |
00:59:09.840
because in a sense, what consciousness is doing is it's insisting that the universe is kind of
link |
00:59:18.640
sequentialized. That is, and it is not allowing the possibility that, oh, there are these multiple
link |
00:59:24.400
threads of time, and they're all flowing differently. It's like saying, no, everything is happening in
link |
00:59:30.640
this one thread of experience that we have. And that illusion of that one thread of experience
link |
00:59:36.160
cannot happen at the planetary scale. Are you saying typical human? Are you saying we are at a
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00:59:41.760
human level special here for consciousness? Well, for our kind of consciousness, if we existed at
link |
00:59:49.520
a scale close to the elementary length, for example, then our perception of the universe
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00:59:53.600
will be absurdly different. But this makes consciousness seem like a weird side effect
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00:59:58.560
to this particular scale. And so who cares? I mean, the consciousness is not that special.
link |
01:00:04.960
I think that a very interesting question is, which I've certainly thought a little bit about,
link |
01:00:10.160
is what can you imagine? What is a sort of factoring of something? What are some other
link |
01:00:16.080
possible ways you could exist, so to speak? And if you were a photon, if you were some kind of
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01:00:23.600
thing that was kind of intelligence represented in terms of photons. For example, the photons we
link |
01:00:32.160
receive in the cosmic microwave background, those photons, as far as their concern, the universe
link |
01:00:36.640
just started. They were emitted 100,000 years after the beginning of the universe. They've
link |
01:00:41.600
been traveling at the speed of light. Time stayed still for them. And then they just arrived and we
link |
01:00:46.800
just detected them. So for them, the universe just started. And that's a different perception of
link |
01:00:53.120
that has implications for a very different perception of time. They don't have that
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01:00:56.800
single thread that seems to be really important for being able to tell a heck of a good story.
link |
01:01:01.840
So we humans tell a story. We can tell a story. Right. We can tell a story. What other kinds of
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01:01:06.880
stories can you tell? So a photon is a really boring story. Yeah. I mean, so that's a, I don't
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01:01:12.640
know if they're a boring story, but I think it's, I've been wondering about this and I've been
link |
01:01:17.280
asking friends of mine who have science fiction writers and things, have you written stuff about
link |
01:01:20.960
this? And I've got one example, great, great collection of books from my friend Rudy Rucker,
link |
01:01:26.080
which were, which I have to say, the, their books about, that are very informed by a bunch of science
link |
01:01:33.200
that I've done. And the thing that I really loved about them is, you know, in the first
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01:01:38.480
chapter of the book, the earth is consumed by these things called nants, which are nano,
link |
01:01:44.080
nanobot type things. Nice. So, you know, so the earth is gone in the first, but then it comes back.
link |
01:01:49.520
But, but, but then spoiler alert. Yeah, right. That was a, that was only a micro spoiler. It's
link |
01:01:54.160
only chapter one. Okay. It's, it's the, but, but the thing that is, is not a real spoiler alert
link |
01:02:01.040
because it's such a complicated concept. But, but in the end, in the end, the, the earth is saved
link |
01:02:07.120
by this thing called the principle of computational equivalence, which is a kind of a core scientific
link |
01:02:11.680
idea of mine. And I was just like, like thrilled. I don't read fiction books very often. And I was
link |
01:02:17.280
just thrilled. I get to the end of this. And it's like, Oh my gosh, you know, everything is saved
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01:02:21.840
by this sort of deep scientific principle. Can you, can you maybe elaborate how the principle
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01:02:26.480
of computational equivalence can save a planet? That would, that would be a terrible spoiler for
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01:02:35.520
me. That would be a spoiler. Okay. But, but, but no, but let me say what the principle of
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01:02:39.040
computational equivalence is. So the question is, you are, you have a system, you have some rule,
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01:02:46.160
you can think of its behavior as corresponding to a computation. The question is, how sophisticated
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01:02:51.280
is that computation? The statement of the principle of computational equivalence is,
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01:02:55.600
as soon as it's, it's not obviously simple, it will be as sophisticated as anything. And so
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01:03:01.520
that has the implication that, you know, rule 30, you know, our brains, other things in physics,
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01:03:08.000
they're all ultimately equivalent in the computations they can do. And that's what leads to
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01:03:12.640
this computational irreducibility idea, because the reason we don't get to jump ahead, you know,
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and outthink rule 30, is because we're just computationally equivalent to rule 30. So we're
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01:03:23.360
kind of just both just running computations that are the same sort of raw, the same level of
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01:03:29.520
computation, so to speak. So that's kind of the, the idea there. And the question, I mean, it's,
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01:03:34.800
it's like, the, you know, in, in the science fiction version would be, okay, somebody says,
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01:03:41.120
we just need more servers, get us more servers. The way to get even more servers is, turn the whole
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01:03:46.880
planet into a bunch of microservers. And that that's, that's where it starts. And so the question of,
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01:03:53.440
you know, computational equivalence principle of computational equivalence is, well, actually,
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01:03:57.520
you don't need to build those custom servers. Actually, you can, you can just use natural
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01:04:05.280
computation to compute things, so to speak, you can use nature to compute, you don't need to have
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01:04:10.880
done all that engineering. And it's kind of the, it's kind of feels a little disappointing that
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01:04:15.840
you say, we're going to build all these servers, we're going to do all these things, we're going
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01:04:19.120
to make, you know, maybe we're going to have human consciousness uploaded into, you know,
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01:04:23.920
some elaborate digital environment. And then you look at that thing, and you say it's got electrons
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01:04:28.480
moving around, just like in a rock. And then you say, well, what's the difference? And the principle
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01:04:33.600
of computational equivalence says, there isn't, at some level, a fundamental, you know, you can't
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01:04:39.200
say mathematically, there's a fundamental difference between the rock that is the future of human
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01:04:45.440
consciousness, and the rock that's just a rock. Now, what I've sort of realized with this kind of
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01:04:51.200
consciousness thing is, there is, there is an aspect of this that seems to be more special,
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01:04:57.840
that isn't, and for example, something I haven't really teased apart properly, is when it comes to
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01:05:03.280
something like the weather and the weather having a mind of its own or whatever, or your average,
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01:05:07.280
you know, pulsar magnetosphere acting like a sort of intelligent thing. How does that relate to,
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01:05:13.520
you know, how, how does, how is that, that entity related to the kind of consciousness that we have
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01:05:20.640
and sort of what would the world look like, you know, to the weather? If we think about the weather
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01:05:25.200
as a mind, what will it perceive? What will it laws, its laws of physics be? I don't really know.
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01:05:30.880
Because it's very parallel. It's very parallel, among other things. And it, it, it's not obvious.
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01:05:37.200
I mean, this is a really kind of mind bending thing, because we've got to try and imagine
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01:05:42.320
where, you know, we've got to try and imagine a parsing of the universe different from the one
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01:05:46.720
we have. And by the way, when we think about extraterrestrial intelligence and so on,
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01:05:51.760
I think that's kind of the key thing is, you know, we've always assumed, I've always assumed,
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01:05:57.040
okay, the extraterrestrials, at least they have the same physics, we all live in the same universe,
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01:06:01.680
they've got the same physics. But actually, that's not really right, because the extraterrestrials
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01:06:07.200
could have a completely different way of parsing that the universe. So it's as if, you know,
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01:06:12.560
there could be for all we know, right here in this room, you know, in the, in the details of the
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01:06:16.800
motion of these gas molecules, there could be an amazing intelligence that we were like, but we
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01:06:22.880
have no way of we're not parsing the universe in the same way. If only we could parse the
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01:06:28.000
universe in the right way, you know, immediately this amazing thing that's going on and this,
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01:06:33.200
you know, huge culture that's developed and all that kind of thing would be obvious to us, but
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01:06:37.040
it's not because we have our particular way of parsing the universe.
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01:06:39.680
Would that thing also have us agency? I don't know the right word to use, but something like
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01:06:45.040
consciousness, but a different kind of consciousness?
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01:06:47.920
I think it's a question of just what you mean by the word, because I think that the, you know,
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01:06:51.600
this notion of consciousness and the, okay, so some people think of consciousness as sort of a key
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01:06:57.040
aspect of it is that we feel that the sort of a feeling of, that we exist in some way, that we
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01:07:04.560
have this intrinsic feeling about ourselves. You know, I suspect that any of these things would
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01:07:12.000
also have an intrinsic feeling about themselves. I've been sort of trying to think recently
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01:07:16.000
about constructing an experiment about what if you were just a piece of a cellular automaton,
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01:07:20.720
let's say, you know, what would your feeling about yourself actually be? And, you know,
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01:07:25.680
can we put ourselves in the, in the shoes, in the cells of the cellular automaton, so to speak?
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01:07:31.440
Can we, can we get ourselves close enough to that, that we could have a sense of what the world
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01:07:36.960
would be like if you were operating in that way? And it's a little difficult because, you know,
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01:07:42.560
you have to not only think about what are you perceiving, but also what's actually going on
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01:07:47.360
in your brain. And our brains do what they actually do. And they don't, it's, you know,
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01:07:52.640
I think there might be some experiments that are possible with, with, you know, neural nets and so
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01:07:57.360
on, where you can have something where you can at least see in detail what's happening inside the
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01:08:02.080
system. And I've been sort of one of the, one of my projects to think about is, is there a way of
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01:08:07.200
kind of, kind of getting a sense, kind of from inside the system about what its view of the world
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01:08:13.840
is and how it, how it, you know, can, can we make a bridge? See, the main issue is this,
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01:08:19.680
what, where, you know, it's a, it's a sort of philosophically difficult thing because
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01:08:24.160
it's like, we do what we do, we understand ourselves, at least to some extent.
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01:08:29.280
We humans understand ourselves.
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01:08:30.800
That's correct. And, but yet, okay, so what are we trying to do? For example, when we are trying
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01:08:35.840
to make a model of physics, what are we actually trying to do? Because, you know, you say, well,
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01:08:40.160
can we work out what the universe does? Well, of course, we can, we just watch the universe,
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01:08:44.160
the universe does what it does. But what we're trying to do when we make a model of physics
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01:08:48.640
is we're trying to get to the point where we can tell a story to ourselves that we understand
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01:08:54.160
that is also a representation of what the universe does. So it's this kind of, you know,
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01:08:58.560
can we make a bridge between what we humans can understand in our minds and what the universe
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01:09:03.440
does. And in a sense, you know, a large part of my kind of life efforts have been devoted to
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making computational language, which kind of is a bridge between what is possible in the
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01:09:15.200
computational universe, and what we humans can conceptualize and think about in a sense what,
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01:09:20.880
you know, when I built Wolfman language and our whole sort of computational language story,
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01:09:25.360
it's all about how do you take sort of raw computation and this ocean of computational
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01:09:30.560
possibility, and how do we sort of represent pieces of it in a way that we humans can understand
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01:09:37.040
and that map on to things that we care about doing. And in a sense, when you add physics,
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01:09:41.920
you're adding this other piece where we can, you know, mediated by computer,
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01:09:46.240
can we get physics to the point where we humans can understand something about what's
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01:09:51.040
happening in it. And when we talk about an alien intelligence, it's kind of the same story. It's
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01:09:56.160
like, is there a way of mapping what's happening there onto something that we humans can understand?
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01:10:02.640
And, you know, physics, in some sense, is like our exhibit one of the story of alien intelligence.
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01:10:09.920
It's a, you know, it's an alien intelligence in some sense. And what we're doing in making a
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01:10:15.600
model of physics is mapping that onto something that we understand. And I think, you know, a lot
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01:10:21.280
of these other things that have I've recently been kind of studying, whether it's molecular
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01:10:25.840
biology, other kinds of things, which we can talk about a bit. Those are other cases where we're,
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01:10:32.800
in a sense, trying to, again, make that bridge between what we humans understand
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01:10:37.680
and sort of the natural language of that sort of alien intelligence in some sense.
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01:10:42.160
When you're talking about just to backtrack a little bit about cellular automata,
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01:10:47.440
being able to, what's it like to be a cellular automata in the way that's equivalent to what
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01:10:56.000
is it like to be a conscious human being? How do you approach that? So is it looking at some
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01:11:04.320
subset of the cellular automata, asking questions of that subset, like how the world is perceived,
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01:11:10.800
how you, as that subset, like for that local pocket of computation, what are you able to say
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01:11:19.040
about the broader cellular type? And that somehow then can give you a sense of how to step outside
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01:11:25.760
of that cellular automata. Right. But the tricky part is that that little subset, it's what it's
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01:11:32.400
doing is it has a view of itself. And the question is, how do you get inside it? It's like, you know,
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01:11:39.120
when we, with humans, right, it's like, we can't get inside each other's consciousness.
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01:11:44.720
That doesn't really, you know, that doesn't really even make sense. It's like, there is an
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01:11:49.680
experience that somebody is having, but you can perceive things from the outside, but sort of
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01:11:54.800
getting inside it, it doesn't quite make sense. And for me, these sort of philosophical issues,
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01:12:00.640
and this one I have not untangled. So let's be, for me, the thing that has been really
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01:12:06.960
interesting in thinking through some of these things is, you know, when it comes to questions
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01:12:11.040
about consciousness or whatever else, it's like, when I can run a program and actually
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01:12:16.000
see pictures and, you know, make things concrete, I have a much better chance to understand what's
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01:12:20.960
going on than when I'm just trying to reason about things in a very abstract way.
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01:12:24.640
Yeah, but there may be a way to map the program to your conscious experience. So for example,
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01:12:32.720
when you play a video game, you do a first person shooter, you walk around inside this entity.
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01:12:39.760
It's a very different thing than watching this entity. So if you can somehow connect,
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01:12:44.720
more and more connect this, this full conscious experience to the subset of the cellular automata.
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01:12:51.200
Yeah, it's something like that. But the difference in the first person shooter thing is there's
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01:12:54.560
still your brain and your memory is still remembering, you know, you, you still have,
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01:13:00.720
it's hard to, I mean, again, what one's going to get, one is not going to actually be able to
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01:13:06.560
be the cellular automaton. One's going to be able to watch what the cellular automaton does.
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01:13:10.800
But this is the frustrating thing that I'm trying to understand, you know, how to,
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01:13:15.520
how to think about being it, so to speak.
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01:13:18.080
Okay, so like in virtual reality, there's a concept of immersion, like with anything,
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01:13:22.000
with video game, with books, there's a concept of immersion. It feels like over time,
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01:13:26.560
if the virtual reality experience is well done, and maybe in the future it'll be extremely well
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01:13:32.720
done, the immersion leads you to feel like you mentioned memories, you forget that you even
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01:13:41.040
ever existed outside that experience. It's so immersive. I mean, you could argue sort of mathematically
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01:13:47.280
that you can never truly become immersed, but maybe you can. I mean, why can't you merge with
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01:13:53.360
the cellular automaton? I mean, aren't you just part of the same fabric? Why can't you just like...
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01:13:59.360
Well, that's a good question. I mean, so let's imagine the following scenario, let's imagine...
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01:14:03.280
Then can you return?
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01:14:05.600
But then can you return back?
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01:14:07.040
Well, yeah, right. I mean, it's like, let's imagine you've uploaded, you know, your brain
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01:14:10.640
is scanned, you've got every synapse, you know, mapped out, you upload everything about you,
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01:14:16.560
the brain simulator, you upload the brain simulator, and the brain simulator is basically,
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01:14:21.440
you know, some glorified cellular automaton. And then you say, well, now we've got an answer to
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01:14:26.320
what does it feel like to be a cellular automaton? It feels just like it felt to be ordinary you,
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01:14:32.160
because they're both computational systems, and they're both, you know, operating in the same way.
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01:14:36.560
So in a sense, but I think there's somehow more to it, because in that sense, when you're just
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01:14:41.440
making a brain simulator, it's just, you know, we're just saying there's another version of our
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01:14:46.880
consciousness. The question that we're asking is, if we tease away from our consciousness,
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01:14:52.000
and get to something that is different, how do we make a bridge to understanding what's going on
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01:14:56.480
there? And, you know, there's a way of thinking about this. Okay, so this is coming on to sort
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01:15:01.360
of questions about the existence of the universe and so on. But one of the things is there's this
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01:15:05.920
notion that we have of rural space. So we have this idea of this physical space, which is, you
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01:15:12.240
know, something you can move around in that's associated with the actual, the extent of the
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01:15:17.200
spatial hypergraph, then there's what we call branchial space, the space of quantum branches.
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01:15:22.480
So in this thing we call the multiway graph of all of this sort of branching histories,
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01:15:28.000
there's this idea of a kind of space where instead of moving around in physical space,
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01:15:32.560
you're moving from history to history, so to speak, from one possible history to another
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01:15:36.560
possible history. And that's kind of a different kind of space that is the space in which quantum
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01:15:42.160
mechanics plays out. Quantum mechanics, like for example, oh, something like, I think we're slowly
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01:15:48.400
understanding things like destructive interference in quantum mechanics, that what's happening is
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01:15:52.960
branchial space is associated with phase and quantum mechanics. And what's happening is the
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01:15:57.840
two photons that are supposed to be interfering and destructively interfering are winding up
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01:16:02.400
at different ends of branchial space. And so us as these poor observers that are trying to,
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01:16:07.520
that have branching brains that are trying to conflate together these different threads of history
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01:16:12.880
and say, we've really got a consistent story that we're telling here, we're really knitting
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01:16:16.720
together these threads of history by the time the two photons wound up at opposite ends of
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01:16:21.520
branchial space, we just can't knit them together to tell a consistent story. So for us, that's
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01:16:27.360
sort of the analog of destructive interference. Got it. And then there's rural space too,
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01:16:31.920
which is the space of rules. Yes. Well, that's another level up. So there's the question.
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01:16:38.880
Actually, I do want to mention one thing, because it's something I've realized in recent times,
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01:16:42.880
and it's, I think it's really, really kind of cool, which is about time dilation and
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01:16:46.640
relativity. And it kind of helps to understand, it's something that kind of helps in understanding
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01:16:51.520
what's going on. So according to relativity, if you have a clock, it's taking at a certain rate,
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01:16:58.240
you send it in a spacecraft that's going at some significant fraction of the speed of light,
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01:17:03.600
to you as an observer at rest, that clock that's in the spacecraft will seem to be ticking much
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01:17:10.000
more slowly. And so in other words, it's kind of like the twin who goes off to Alpha Centauri
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01:17:16.640
and goes very fast will age much less than the twin who's on Earth that is just hanging out
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01:17:22.480
where they're hanging out. Okay, why does that happen? Okay, so it has to do with what motion is. So
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01:17:29.360
in in our models of physics, what is motion? Well, when you move from somewhere to somewhere,
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01:17:34.880
it's you're having to sort of recreate yourself at a different place in space. When you exist at
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01:17:41.600
a particular place, and you just evolve with time, you're again, you're updating yourself,
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01:17:46.080
you're you're following these rules to update what happens. Well, so the question is when you
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01:17:51.200
have a certain amount of computation in you, so to speak, when there's a certain amount,
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01:17:55.440
you know, you're computing the universe is computing at a certain rate, you can either use
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01:17:59.760
that computation to work out sitting still where you are, what's going to happen successfully in
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01:18:05.600
time, or you can use that computation to recreate yourself as you move around the universe. And so
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01:18:11.440
time dilation ends up being, it's really cool, actually, that this is explainable in a in a way
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01:18:16.400
that isn't just imagine the mathematics of relativity. But that time dilation is a story
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01:18:21.760
of the fact that as you kind of are recreating yourself as you move, you are using up some
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01:18:27.840
of your computation. And so you don't have as much computation left over to actually work out what
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01:18:33.120
happens progressively with time. So that means that time is running more slowly for you, because
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01:18:38.880
it is you're you're using up your computation, your clock can't tick as quickly, because every
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01:18:45.360
tick of the clock is using up some computation, but you already use that computation up on moving at,
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01:18:50.080
you know, half the speed of light or something. And so that's that's why time dilation happens.
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01:18:55.520
And so you can you can start so it's kind of interesting that one can sort of get an intuition
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01:19:00.240
about something like that, because it has seemed like just a mathematical fact about the mathematics
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01:19:05.120
of special relativity and so on. Well, for me, it's a little bit confusing what the you in that
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01:19:10.160
picture is, because you're using up computation. Okay, so so we're simply saying the entity is
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01:19:19.280
updating itself according to the way that the universe updates itself. And the question is,
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01:19:25.600
you're, you know, those updates, let's imagine the you as a clock. Okay. And the clock is, you
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01:19:31.120
know, there's all these little updates, the hypergraph and a sequence of updates cause the
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01:19:35.840
pendulum to swing back the other way, and then swing back, swinging back and forth. Okay. And
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01:19:41.440
all of the all of those updates are contributing to the motion of, you know, the pendulum going
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01:19:47.040
back and forth or the little oscillator moving, whatever it is. Okay. But but then the alternative
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01:19:52.640
is that sort of situation one, where the thing is at rest, situation two, where it's kind of moving
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01:19:58.480
the the what's happening is, it is having to recreate itself at every, at every moment,
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01:20:04.160
the thing is going to have to do the computations to be able to sort of recreate itself at a
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01:20:10.240
different position in space. And that's kind of the intuition behind. So it's either going to
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01:20:15.120
spend its computation, recreating itself at a different position in space, or it's going to
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01:20:19.760
spend its computation doing the sort of doing the updating of the, you know, of the ticking of the
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01:20:27.520
clock, so to speak. So the more updating is doing the less the ticking of the clock updates doing.
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01:20:33.360
That's right. The more it has having to update because of motion, yeah, the less it can update
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01:20:37.360
the clock. So that that's, I mean, obviously, there's a there's a sort of mathematical version
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01:20:42.880
of it that relates to how it actually works in relativity. But that's kind of, to me, that
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01:20:47.440
was sort of exciting to me that it's possible to have a really mechanically explainable story there
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01:20:53.120
that that isn't, and it's similarly in quantum mechanics, this notion of branching brains,
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01:20:57.520
perceiving branching universes. To me, that's getting towards a sort of mechanically explainable
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01:21:02.080
version of what happens in quantum mechanics, even though it's a little bit mind bending,
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01:21:06.480
to see, you know, these things about under what circumstances can you successfully knit together
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01:21:12.080
those different threads of history, and when do things sort of escape, and those kinds of things.
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01:21:17.200
But the, you know, the thing about this physical space and physical space, the the main sort of
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01:21:24.160
big theory is general relativity, the theory of gravity. And that tells you how things move in
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01:21:28.960
physical space. In branching space, the big theory is the Feynman path integral, which,
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01:21:34.240
it turns out, tells you essentially how things move in quantum, in the space of quantum phases.
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01:21:39.840
So it's kind of like motion in branching space. And it's kind of a fun thing to start thinking
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01:21:45.120
about what, oh, you know, all these things that we know in physical space, like event horizons
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01:21:51.280
and black holes and so on, what are the analogous things in branching space, for example, the speed
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01:21:55.360
of light, what's the analog of the speed of light in branching space, it's the maximum speed of
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01:21:59.840
quantum entanglement. So the speed of light is a flash bulb goes off here, what's the maximum
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01:22:06.320
rate at which the effect of that flash bulb is detectable moving away in space. So similarly,
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01:22:13.280
in branching space, something happens. And the question is, how far in this branching space,
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01:22:18.320
in the space of quantum states, how far away can that get within a certain period of time.
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01:22:23.760
And so there's this notion of a maximum entanglement speed. And that might be observable,
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01:22:28.720
that's the thing we've been sort of poking at, is might there be a way to observe it,
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01:22:32.800
even in some atomic physics kind of situation. Because one of the things that's weird in quantum
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01:22:38.240
mechanics is we're, you know, when we study quantum mechanics, we mostly study it in terms
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01:22:43.760
of small numbers of particles, you know, this electron does this, this thing on an ion trap
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01:22:48.000
does that and so on. But when we deal with large numbers of particles, kind of all bets are off,
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01:22:52.320
it's kind of too complicated to deal with quantum mechanics. And so what ends up happening is,
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01:22:57.200
so this question about maximum entanglement speed and things like that may actually play
link |
01:23:02.320
in one of these, in the sort of story of many body quantum mechanics, and even have some suspicions
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01:23:07.520
about things that might happen, even in one of the things I realized I'd never understood,
link |
01:23:13.440
and it's kind of embarrassing, but I think I now understand a little better, is when you have chemistry
link |
01:23:18.320
and you have quantum mechanics, it's like, well, there's two carbon atoms as this molecule and
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01:23:23.120
we do a reaction, and we draw a diagram and we say this carbon atom ends up in this place.
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01:23:28.000
And it's like, but wait a minute, in quantum mechanics, nothing ends up in a definite place.
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01:23:31.760
There's always just some wave function for this to happen. How can it be the case
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01:23:35.600
that we can draw these reasonable, it just ended up in this place. And you have to kind of say,
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01:23:39.840
well, the environment of the molecule effectively made a bunch of measurements on the molecule
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01:23:44.800
to keep it kind of classical. And that's a story that has to do with
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01:23:48.880
this whole thing about, you know, measurements have to do with this idea of, you know, can we
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01:23:55.360
conclude that something definite happened? Because in quantum mechanics, the intrinsic
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01:23:59.600
quantum mechanics, the mathematics of quantum mechanics is all about, they're just these
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01:24:03.040
amplitudes for different things to happen. Then there's this thing of, and then we make a measurement,
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01:24:08.080
and we conclude that something definite happened. And that has to do with this thing,
link |
01:24:12.080
I think, about sort of moving about knitting together these different threads of history
link |
01:24:17.200
and saying, this is now something where we can definitively say something definite happened.
link |
01:24:21.200
In the traditional theory of quantum mechanics, it's just like, you know, after you've done
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01:24:25.840
all this amplitude computation, then this big hammer comes down, and you do a measurement,
link |
01:24:30.560
and it's all over. And that's been very confusing. For example, in quantum computing,
link |
01:24:34.640
it's been a very confusing thing. Because when you say, you know, in quantum computing,
link |
01:24:38.720
the basic idea is you're going to use all these separate threads of computation, so to speak,
link |
01:24:43.200
to do all the different parts of, you know, try these different factors for an integer or
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01:24:46.800
something like this. And it looks like you can do a lot because you've got all these different
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01:24:51.120
threads going on. But then you have to say, well, at the end of it, you've got all these threads,
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01:24:56.080
and every thread came up with a definite answer, but we got to conflate those together to figure
link |
01:25:00.880
out a definite thing that we humans can take away from it, a definite so the computer actually
link |
01:25:05.760
produced this output. So having this branchial space and this hypergraph model of physics,
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01:25:13.360
do you think it's possible to then make predictions that are definite about many body
link |
01:25:19.520
quantum mechanical systems? Is that the hope? I think it's likely, yes. But I don't, you know,
link |
01:25:24.720
this is every one of these things, when you, when you go from the underlying theory, which is
link |
01:25:29.120
complicated enough, and it's, I mean, the theory at some level is beautifully simple. But as soon
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01:25:34.000
as you start actually trying to, it's this whole question about how do you bridge it to things
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01:25:38.000
that we humans can talk about? It gets really complicated. And this thing about actually getting
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01:25:43.840
it to a definite prediction about, you know, definite thing you can say about chemistry
link |
01:25:50.000
or something like this, you know, that's just a lot of work. So I'll give you an example.
link |
01:25:53.840
There's a thing called the quantum Zeno effect. So the idea is, you know, quantum stuff happens,
link |
01:25:59.920
but then if you make a measurement, you're kind of freezing time in quantum mechanics. And so it
link |
01:26:06.080
looks like there's a possibility that with sort of the relationship between the quantum Zeno effect
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01:26:11.040
and the way that many body quantum mechanics works and so on, maybe just conceivably, it may be
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01:26:16.560
possible to actually figure out a way to measure the maximum entanglement speed. And the reason we
link |
01:26:22.320
can potentially do that is because the systems we deal with in terms of atoms and things, they're
link |
01:26:27.760
pretty big, you know, a mole of atoms is, you know, is a lot of atoms. And, you know, but it isn't a
link |
01:26:33.040
very, you know, it's something where to get, you know, when we're dealing with how can you see 10
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01:26:37.680
to the minus 100, so to speak, well, by the time you've got, you know, 10 to the 30th atoms, you're
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01:26:43.680
not, you know, you're within a little bit closer striking distance of that. It's not like, oh,
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01:26:48.640
we've just got, you know, two atoms, and we're trying to see down to 10 to the minus 100 meters
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01:26:54.400
or whatever. So I don't know how it will work, but this is a, this is a potential direction.
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01:26:59.920
And if you can tell, by the way, if we could measure the maximum entanglement speed, we would
link |
01:27:04.720
know the elementary length. These are all related. So if we got that one number, we just need one
link |
01:27:10.560
number, if we can get that one number, we can, you know, the theory has no parameters anymore.
link |
01:27:16.000
And, you know, there are other places, well, there's another hope for doing that,
link |
01:27:21.040
is in cosmology. In this model, one of the features is the universe is not fixed dimensional.
link |
01:27:26.240
I mean, we think we live in three dimensional space, but this hypergraph doesn't have any
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01:27:29.920
particular dimension. It can emerge as something which on an approximation, it's as if, you know,
link |
01:27:36.000
you say, what's the volume of a sphere in the hypergraph where a sphere is defined as
link |
01:27:40.720
how many nodes do you get to when you go a distance r away from a given point?
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01:27:44.480
And you can say, well, if I get to about r cube nodes, when I go a distance r away in the
link |
01:27:51.120
hypergraph, then I'm living roughly in three dimensional space. But you might also get to r
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01:27:55.920
to the point, you know, 2.92, you know, for some value of r in, you know, as r increases,
link |
01:28:03.200
that might be the sort of fit to what happens. And so one of the things we suspect is that
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01:28:08.000
the very early universe was essentially infinite dimensional. And that as the universe expanded,
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01:28:14.240
it became lower dimensional. And so one of the things that is another little sort of point
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01:28:19.680
where we think there might be a way to actually measure some things is dimension fluctuations
link |
01:28:24.240
in the early universe. That is, is there a, is there leftover dimension fluctuation of
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01:28:29.600
at the time of the cosmic microwave background, 100,000 years or something after the beginning
link |
01:28:33.280
of the universe? Is it still the case that there are, there were pieces of the universe
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01:28:37.840
that didn't have dimension three, that had dimension 3.01 or something? And can we tell that?
link |
01:28:43.280
Is that possible to observe fluctuations in dimensions? I don't even know what that entails.
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01:28:51.040
Okay, so the question, which should be an elementary exercise in electrodynamics,
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01:28:56.400
except it isn't, is understanding what happens to a photon when it propagates through 3.01
link |
01:29:02.080
dimensional space. So for example, the inverse square law is a consequence of the, you know,
link |
01:29:07.440
the surface area of a sphere is proportional to R squared. But if you're not in three dimensional
link |
01:29:14.800
space, the surface area of sphere is not proportional to R squared, it's R to the whatever, 2.01
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01:29:21.280
or something. And so that means that I think when you kind of try and do optics, you know,
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01:29:28.480
a common principle in optics is Huygens principle, which basically says that every piece of a
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01:29:33.520
wave front of light is a source of new spherical waves. And those spherical waves, if they're
link |
01:29:40.880
different dimensional spherical waves, will have other characteristics. And so there will be bizarre
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01:29:46.960
optical phenomena, which we haven't figured out yet. So you're looking for some weird
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01:29:53.600
photon trajectories that designate that it's 3.01 dimensional space? Yeah. Yeah, that would be an
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01:30:01.360
example of, I mean, you know, there are there are only a certain number of things we can measure
link |
01:30:04.960
about photons, you know, we can measure their polarization, we can measure their frequency,
link |
01:30:09.360
we can measure their direction, those kinds of things. And, you know, how that all works out.
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01:30:15.360
And, you know, in the current models of physics, you know, it's been hard to explain how the
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01:30:21.360
universe manages to be as uniform as it is. And that's led to this inflation idea that to the
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01:30:27.760
great annoyance of my then collaborator, I we had, we figured out in like 1979, we had this
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01:30:32.560
realization that you could get something like this. But it seemed implausible that that's the
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01:30:36.880
way the universe worked. So we put in a footnote. And that was, so that's a, but in any case, I've
link |
01:30:42.720
never really completely believed it. But this, that's an idea for how to sort of puff out the
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01:30:47.840
universe faster than the speed of light, early moments of the universe, that that's the sort of
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01:30:52.320
the inflation idea. And that you can somehow explain how the universe manages to be as uniform as it
link |
01:30:58.800
is. In our model, this turns out to be much more natural, because the universe just starts very
link |
01:31:04.960
connected, the hypergraph is not such that the ball that you grow starting from a single point has
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01:31:10.560
volume r cubed, it might have volume r to the 500 or r to the infinity. And so that means that you
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01:31:18.320
sort of naturally get this much higher degree of connectivity and uniformity in the universe.
link |
01:31:22.560
And then the question is, this is sort of the mathematical physics challenge is in the standard
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01:31:28.080
theory of the universe, there's the Friedman, Roberts and Walker universe, which is the kind
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01:31:32.320
of standard model where the universe is isotropic and homogeneous. And you can then work out the
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01:31:36.960
equations of general relativity, and you can figure out how the universe expands. We would like to do
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01:31:41.760
the same kind of thing, including dimension change. This is just difficult mathematical physics.
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01:31:46.960
I mean, the fundamental reason it's difficult, when people invented calculus 300 years ago,
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01:31:53.840
calculus was the story of understanding change and change as a function of a variable.
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01:31:59.840
And so people study univariate calculus, they study multivariate calculus, it's one variable,
link |
01:32:04.480
it's two variables, three variables, but whoever studied 2.5 variable calculus turns out nobody.
link |
01:32:11.680
It turns out that, but what we need to have to understand these fractional dimensional
link |
01:32:17.200
spaces, which don't work like, well, they're spaces where the effective dimension is not
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01:32:24.880
an integer. So you can't apply the tools of calculus and natural and easily to fractional
link |
01:32:30.560
dimensions? No.
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01:32:31.440
So somebody has to figure out how to do that. Yeah, we're trying to figure this out. I mean,
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01:32:35.920
it's very interesting. I mean, it's very connected to very frontier issues in mathematics,
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01:32:40.720
it's very beautiful. So is it possible, we're dealing with a scale that's so,
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01:32:46.880
so much smaller than our human scale, is it possible to make predictions versus explanations?
link |
01:32:53.520
Do you have a hope that with this hypergraph model, you'd be able to make predictions?
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01:32:59.680
That that could be validated with a physics experiment, predictions that couldn't have
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01:33:05.520
been done or weren't done otherwise. In which domain do you think?
link |
01:33:10.960
Okay, so they're going to be cosmology ones to do with dimension fluctuations in the universe.
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01:33:14.640
That's a very bizarre effect. Dimension fluctuation is just something nobody ever looked for that.
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01:33:19.440
If anybody sees dimension fluctuation, that's a huge flag, that's something like our model
link |
01:33:25.040
is going on. And how one detects that, that's a problem of traditional physics,
link |
01:33:32.160
in a sense of what's the best way to actually figure that out. And for example, that's one,
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01:33:38.240
there are all kinds of things one can imagine. I mean, there are things that in black hole mergers,
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01:33:44.400
it's possible that there will be effects of maximum entanglement speed in large black hole
link |
01:33:49.440
mergers. That's another possible thing. And all of that is detected through,
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01:33:54.720
like what, do you have a hope for a LIGO type of situation, like that's gravitational waves?
link |
01:33:59.360
Yeah, or alternatively, I mean, I think it's, look, figuring out experiments is like
link |
01:34:06.560
figuring out technology inventions. That is, you've got a set of raw materials,
link |
01:34:11.040
you've got an underlying model, and now you've got to be very clever to figure out,
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01:34:15.280
what is that thing I can measure that just somehow leverages into the right place.
link |
01:34:20.960
And we've spent less effort on that than I would have liked, because one of the reasons is that
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01:34:27.120
I think that the physicists who've been working on our models, we've now lots of physicists,
link |
01:34:34.160
actually, it's very, very nice. It's kind of, it's one of these cases where I'm almost,
link |
01:34:39.040
I'm really kind of pleasantly surprised that the sort of absorption of the things we've done
link |
01:34:43.600
has been quite rapid and quite sort of very positive.
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01:34:48.720
So it's a camber and explosion of physicists too, and not just ideas.
link |
01:34:51.760
Yes, I mean, you know, a lot of what's happened, that's really interesting. And again, not what
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01:34:57.200
I expected is there are a lot of areas of sort of very elaborate, sophisticated mathematical
link |
01:35:03.200
physics, whether that's causal set theory, whether it's higher category theory, whether it's
link |
01:35:08.240
categorical quantum mechanics, all sorts of elaborate names for these things, spin networks,
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01:35:13.120
perhaps, you know, causal dynamical triangulations, all kinds of names of these fields. And these
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01:35:19.760
fields have a bunch of good mathematical physicists in them, who've been working for decades in
link |
01:35:24.480
these particular areas. And the question is, but they've been building these mathematical
link |
01:35:29.680
structures. And the mathematical structures are interesting, but they don't typically sit on
link |
01:35:34.240
anything. They're just mathematical structures. And I think what's happened is our models provide
link |
01:35:39.360
kind of a machine code that lives underneath those models. So a typical example, this is
link |
01:35:44.800
a due to Jonathan Gorod, who's one of the key people who's been working on a project.
link |
01:35:51.280
This is in, okay, so I'll give you an example just to give a sense of how these things connect.
link |
01:35:56.160
This is in causal set theory. So the idea of causal set theory is there are, in space time,
link |
01:36:02.880
we imagine that there's space and time, it's a three plus one dimensional, you know, set up,
link |
01:36:08.160
we imagine that there are just events that happen at different times and places in space and time.
link |
01:36:15.280
And the idea of causal set theory is the only thing you say about the universe is there are
link |
01:36:19.680
a bunch of events that happen sort of randomly at different places in space and time. And then
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01:36:24.800
the whole sort of theory of physics has to be to do with this graph of causal relationships
link |
01:36:30.480
between these randomly thrown down events. So they've always been confused by the fact that
link |
01:36:36.880
to get even Lorentz invariance, even relativistic invariance, you need a very special way to throw
link |
01:36:41.680
down those events. And they've had no natural way to understand how that would happen. So what
link |
01:36:46.640
Jonathan figured out is that, in fact, from our models, they instead of just generating events at
link |
01:36:54.240
random, our models necessarily generate events in some pattern in space time effectively, that
link |
01:37:01.200
then leads to Lorentz invariance and relativistic invariance and all those kinds of things. So it's
link |
01:37:05.280
a place where all the mathematics that's been done on, well, we just have a random collection of
link |
01:37:09.440
events. Now, what consequences does that have in terms of causal set theory and so on, that can
link |
01:37:15.520
all be kind of wheeled in now that we have some different underlying foundational idea for what
link |
01:37:21.520
the particular distribution of events is as opposed to just what we throw down random events.
link |
01:37:26.400
And so that's a typical sort of example of what we're seeing in all these different areas of kind
link |
01:37:32.160
of how you can take really interesting things that have been done in mathematical physics
link |
01:37:36.480
and connect them. And it's really kind of beautiful because the abstract models we have
link |
01:37:43.440
just seem to plug into all these different very interesting, very elegant abstract ideas. But
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01:37:48.800
we're now giving sort of a reason for that to be the way, a reason for one to care. I mean,
link |
01:37:54.960
it's like saying, you can think about computation abstractly. You can think about, I don't know,
link |
01:38:01.680
combinators or something as abstract computational things. And you can sort of do all kinds of
link |
01:38:06.320
study of them. But it's like, why do we care? Well, okay, Turing machines are a good start
link |
01:38:10.880
because you can kind of see that sort of mechanically doing things. But when we actually
link |
01:38:14.320
start thinking about computers, computing things, we have a really good reason to care. And this
link |
01:38:19.520
is sort of what we're what we're providing, I think, is a reason to care about a lot of these
link |
01:38:23.920
areas of mathematical physics. So that's been, that's been very nice. So I'm not sure we've
link |
01:38:28.640
ever got to the question of why does the universe exist at all?
link |
01:38:33.120
No, let's talk about that. Yes.
link |
01:38:35.120
So we're, it's not the simplest question in the world. So it takes a few steps to get to it.
link |
01:38:41.440
And it's nevertheless even surprising that you can even begin to answer this question,
link |
01:38:45.920
as you were saying. I'm very surprised. So the next thing to perhaps understand is this idea
link |
01:38:53.360
of rural space. So we've got kind of physical space, we've got bronchial space, the space of
link |
01:38:59.520
possible quantum histories. And now we've got another level of kind of abstraction, which is
link |
01:39:04.960
rural space. And here's the, here's where that comes from. So you say, okay, you say we've got
link |
01:39:11.040
this model for the universe, we've got a particular rule, and we run this rule, and we get the
link |
01:39:16.400
universe. Okay, so that's, that's interesting. Why that rule? Why not another rule? And so that
link |
01:39:22.480
confused me for a long time. And I realized, well, actually, what if the thing could be
link |
01:39:28.560
using all possible rules? What if at every step, in addition to saying apply a particular rule
link |
01:39:34.640
at all places in this hypergraph, one could say, just take all possible rules and apply
link |
01:39:39.600
all possible rules at all possible places in this hypergraph. Okay. And then you make this
link |
01:39:44.560
rural multiway graph, which both is all possible histories for a particular rule and all possible
link |
01:39:50.480
rules. So the next thing you'd say is, how can you get anything reasonable? How can anything,
link |
01:39:55.440
you know, real come out of the set of all possible rules applied in all possible ways?
link |
01:40:00.800
Okay, this is a subtle thing. So which I haven't fully untangled. The there is this object,
link |
01:40:07.200
which is the result of running all possible rules in all possible ways. And you might say,
link |
01:40:12.080
if you're running all possible rules, why can't everything possible happen? Well, the answer is
link |
01:40:17.040
because when you there's sort of this entanglement that occurs. So let's say that you have a lot
link |
01:40:24.720
of different possible initial conditions, a lot of different possible states, then you're applying
link |
01:40:29.280
these different rules. Well, some of those rules can end up with the same state. So it isn't the
link |
01:40:35.120
case that you can just get from anywhere to anywhere. There's this whole entangled structure
link |
01:40:39.440
of what can lead to what and there's a definite structure that's produced. I think I'm going
link |
01:40:43.920
to call that definite structure, the RULIAD, the limit of the limits of kind of all possible rules
link |
01:40:50.560
being applied in all possible ways. And you're saying that structure is finite, so that somehow
link |
01:40:55.360
connects to maybe a similar kind of thing as like causal invariance. Well, RULIAD necessarily has
link |
01:41:01.760
causal invariance. That's a feature of that's just a mathematical consequence of essentially
link |
01:41:06.400
using all possible rules, plus universal computation gives you the fact that from any
link |
01:41:12.000
diverging paths you can always, the paths will always convert.
link |
01:41:15.280
But does that necessarily infer that the RULIAD is a finite?
link |
01:41:21.760
In the end, it's not necessarily finite. I mean, it's just like the history of the universe may
link |
01:41:27.920
not be finite. The history of the universe, time may keep going forever. You can keep running the
link |
01:41:32.240
computations of the RULIAD and you'll keep spewing out more and more and more structure. It's like
link |
01:41:37.680
time doesn't have to end. But the issue is there are three limits that happen in this RULIAD object.
link |
01:41:46.480
One is how long you run the computation for. Another is how many different rules you're
link |
01:41:51.360
applying. Another is how many different states you start from. And the mixture of those three
link |
01:41:56.960
limits, I mean, this is just mathematically a horrendous object. And what's interesting about
link |
01:42:02.720
this object is the one thing that does seem to be the case about this object is it connects
link |
01:42:07.280
with ideas in higher category theory. And in particular, it connects to some of the 20th
link |
01:42:12.080
century's most abstract mathematics done by this chap, growth and deke. Growth and deke had a thing
link |
01:42:17.760
called the infinity group void, which is closely related to this RULIAD object. Although the details
link |
01:42:24.240
of the relationship, you know, I don't fully understand yet. But I think that what's interesting
link |
01:42:31.440
is this thing that is sort of this very limiting object. So okay, so a way to think about this,
link |
01:42:36.320
that again, will take us into another direction, which is the equivalence between physics and
link |
01:42:41.680
mathematics. The way that, well, let's see, maybe this is just to give a sense of this kind of
link |
01:42:50.560
group void and things like that, you can think about in mathematics, you can think you have
link |
01:42:54.320
certain axioms, they're kind of like atoms. And you, well, actually, let's say, let's talk about
link |
01:43:01.200
mathematics for a second. So what is mathematics? What is what is it made of, so to speak? Mathematics,
link |
01:43:06.960
there's a bunch of statements like, for addition, x plus y is equal to y plus x, that's a statement
link |
01:43:12.960
of mathematics. Another statement would be, you know, x squared minus one is equal to x plus
link |
01:43:17.440
one x minus one. There are infinite number of these possible statements of mathematics.
link |
01:43:21.840
So it's not, I mean, it's not just I guess a statement, but with x plus y, it's a rule that
link |
01:43:27.040
you can, I mean, you think of it as a rule. It's a, it is a rule. It's also just a thing that is
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01:43:34.480
true in mathematics. The statement is true. Right. And what you can imagine is you imagine just
link |
01:43:41.200
laying out this giant kind of ocean of all statements, well, actually, you first start,
link |
01:43:47.280
okay, this is where this was segwaying into a different thing. Let me not go in this direction
link |
01:43:51.840
for a second. Let's not go to meta mathematics just yet. Yeah, we'll maybe get to meta mathematics,
link |
01:43:56.320
but it's, so let me not, let me explain the groupoid and things later. Yes. But so let's
link |
01:44:03.040
come back to the universe, always a good place to be in. So what does the universe have to do
link |
01:44:09.280
with the rule of the all space and how that's possibly connected to why the thing exists at all
link |
01:44:16.880
and why there's just one of them? Yes. Okay. So here's the point. So the thing that had confused
link |
01:44:22.400
me for a long time was, let's say we get the rule for the universe, we hold it in our hand,
link |
01:44:27.520
we say, this is our universe. Then the immediate question is, well, why isn't it another one?
link |
01:44:32.240
And, you know, that's kind of the, you know, the, the sort of the lesson of Copernicus is,
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01:44:36.960
we're not very special. So how come we got universe number 312 and not universe quadriline,
link |
01:44:44.320
quadriline, quadriline. And I think the resolution of that is the realization that
link |
01:44:48.720
there, that the universe is running all possible rules. So then you say, well, how on earth do we
link |
01:44:57.440
perceive the universe to be running according to a particular rule? How do we perceive definite
link |
01:45:01.920
things happening in the universe? Well, it's the same story. It's the observer, there is a reference
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01:45:08.000
frame that we are picking in this rural space. And that that is what determines our perception
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01:45:13.920
of the universe. With our particular sensory information and so on, we are parsing the universe
link |
01:45:19.840
in this particular way. So here's the way to think about it. In, in, in physical space,
link |
01:45:24.720
we live in a particular place in the universe. And, you know, we could live on Alpha Centauri,
link |
01:45:29.040
but we don't, we live here. And similarly, in rural space, we could live in many different
link |
01:45:36.160
places in rural space, but we happen to live here. And what does it mean to live here? It means
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01:45:40.960
we have certain sensory input. We have certain ways to parse the universe. Those are our
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01:45:46.960
interpretation of the universe. What would it mean to travel in rural space? What it basically
link |
01:45:52.080
means is that we are successively interpreting the universe in different ways. So in other words,
link |
01:45:56.960
to be at a different point in rural space is to have a different, in a sense, a different
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01:46:01.920
interpretation of what's going on in the universe. And we can imagine even things like an analog of
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01:46:07.200
the speed of light as the maximum speed of translation in rural space and so on.
link |
01:46:12.400
So wait, what's the interpretation? So rural space, we, I'm confused by the we and the
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01:46:19.760
interpretation and the universe. I thought moving about in rural space changes the way the universe
link |
01:46:28.240
is, is the way we would perceive it. The way that that ultimately has to do with the perception.
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01:46:35.280
So it doesn't real, rural space is not somehow changing, like,
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01:46:43.200
branching into another universe, something like that. No, I mean, the point is that the whole
link |
01:46:47.840
point of this is the Rouliat is sort of the encapsulated version of everything that is the
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01:46:54.800
universe running according to all possible rules. Yeah, we think of our universe, the observable
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01:46:59.840
universe as its thing. So we're a little bit loose with the word universe then, because wouldn't the
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01:47:07.280
Rouliat potentially encapsulate a very large number, like combinatorially large, maybe infinite
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01:47:15.440
set of what we human physicists think of as universes.
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01:47:20.080
That's an interesting, interesting parsing of the word universe, right? Because what we're
link |
01:47:24.800
saying is just as we're at a particular place in physical space, we're at a particular place in
link |
01:47:28.800
rural space. At that particular place in rural space, our experience of the universe is this,
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01:47:34.800
just as if we lived at the center of the galaxy, our universe, our experience of the universe
link |
01:47:38.400
will be different from the one it is, given where we actually live. And so in what we're saying is
link |
01:47:45.440
when you might say, I mean, in a sense, this Rouliat is sort of a super universe, so to speak.
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01:47:51.760
But it's all entangled together. It's not like you can separate out, you can say,
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01:47:56.000
let me, it's like when we take a reference, okay, it's like our experience of the universe is
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01:48:00.960
based on where we are in the universe. We could imagine moving to somewhere else in the universe,
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01:48:05.680
but it's still the same universe. So there's not like universes existing in parallel?
link |
01:48:12.160
No. Because, and the whole point is that if we were able to change our interpretation of
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01:48:19.200
what's going on, we could perceive a different reference frame in this Rouliat.
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01:48:25.120
Yeah, but that's not, that's just, yeah, that's the same Rouliat. That's the same universe.
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01:48:32.320
You're just moving about. These are just coordinates in the universe.
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01:48:35.680
So the way that's, the reason that's interesting is, imagine the extraterrestrial intelligence,
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01:48:40.800
so the alien intelligence, we should say. The alien intelligence might live on Alpha Centauri,
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01:48:47.200
but it might also live at a different place in rural space.
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01:48:50.080
It can live right here on Earth. It just has a different reference frame that
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01:48:54.000
includes a very different perception of the universe. And then because that rural space is
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01:49:00.560
very large, I mean... Do we get to communicate with them? Right, that's...
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01:49:06.480
Yeah, but it's also, well, one thing is how different the perception of the universe could be.
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01:49:14.640
I think it could be bizarrely, unimaginably, completely different. And I mean, one thing to
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01:49:20.800
realize is, even in kind of things I don't understand well, I know about the kind of
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01:49:27.120
Western tradition of understanding science and all that kind of thing. And you talk to people
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01:49:32.400
who say, well, I'm really into some Eastern tradition of this, that and the other. And
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01:49:39.600
it's really obvious to me how things work. I don't understand it at all. But it is not obvious,
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01:49:46.560
I think, with this kind of realization that there's these very different ways to interpret
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01:49:51.040
what's going on in the universe. That kind of gives me at least... It doesn't help me to understand
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01:49:55.440
that different interpretation, but it gives me at least more respect for the possibility that
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01:50:00.160
there will be other interpretations. Yeah, it humbles you to the possibility that,
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01:50:04.160
like, what is it? Reincarnation or all these, like, eternal recurrence with Nietzsche? Like,
link |
01:50:10.000
just these ideas? Yeah. Well, you know, the thing that I realized about a bunch of those things is
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01:50:15.200
that, you know, I've been sort of doing my little survey of the history of philosophy, just trying
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01:50:19.280
to understand, you know, what can I actually say now about some of these things? And you realize
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01:50:24.080
that some of these concepts, like the immortal soul concept, which, you know, I remember when I was a
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01:50:29.600
kid and, you know, it was kind of a lots of religion bashing type stuff of people saying, you know,
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01:50:35.440
well, we know about physics. Tell us how much does a soul weigh? And people are like, well,
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01:50:41.760
how can it be a thing if it doesn't weigh anything? Well, now we understand, you know,
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01:50:46.400
there is this notion of what's in brains that isn't the matter of brains, and it's something
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01:50:50.800
computational. And there is a sense, and in fact, it is correct that it is in some sense immortal,
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01:50:56.320
because this pattern of computation is something abstract that is not specific to the particular
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01:51:01.440
material of a brain. Now, we don't know how to extract it, you know, in our traditional scientific
link |
01:51:07.360
approach. But it's still something where it isn't a crazy thing to say there is something,
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01:51:12.960
it doesn't weigh anything. That's a kind of a silly question. How much does it weigh? Well,
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01:51:18.240
actually, maybe it isn't such a silly question in our model of physics, because the actual
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01:51:22.480
computational activity has has a consequence for gravity and things. But that's a very subtle
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01:51:27.600
you can talk about mass and energy and so on. There could be a what would you call a solitron.
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01:51:33.680
Yes, yes. A particle that somehow contains soleness.
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01:51:39.280
Yeah, right. Well, that's what, by the way, that's what Leibniz said. And, you know, one thing,
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01:51:44.160
I've never understood this, you know, Leibniz had this idea of monads and monodology, and he had
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01:51:48.720
this idea that what exists in the universe is this big collection of monads, and that the only
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01:51:54.400
thing that one knows about the monads is sort of how they relate to each other. It sounds awfully
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01:51:59.040
like hypergraphs, right? But Leibniz had really lost me at the following thing. He said, each of
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01:52:04.960
these monads has a soul, and each of them has a consciousness. And it's like, okay, I'm out of
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01:52:10.320
here. I don't understand this at all. I don't know what's going on. But I realized recently
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01:52:14.480
that in his day, the concept that a thing could do something could spontaneously do something,
link |
01:52:21.440
that was his only way of describing that. And so what I would now say as well is this
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01:52:26.160
this abstract rule that runs to Leibniz, that would have been, you know, in 1690 or whatever,
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01:52:32.000
that would have been kind of, well, it has a soul, it has a consciousness. And so, you know,
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01:52:37.440
in a sense, it's like one of these, there's no new idea under the sun, so to speak. That's, you
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01:52:42.000
know, that's a sort of a version of the same kinds of ideas, but couched in terms that are sort of
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01:52:47.440
bizarrely different from the ones that we would use today.
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01:52:49.840
Would you be able to maybe play devil's advocate on your conception of consciousness that like the
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01:52:56.640
two characteristics of it that is constrained and there's a single thread of time? Is it possible
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01:53:02.320
that Leibniz was onto something that the basic atom, the screwy atom of space has a consciousness?
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01:53:11.120
Is that, so these are just words, right? But what is there, is there some sense where consciousness
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01:53:18.000
is much more fundamental than you're making it seem?
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01:53:21.600
I don't know. I mean, that, you know, I think...
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01:53:24.000
Can you construct a world in which it is much more fundamental?
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01:53:27.360
I think that, okay, so the question would be, is there a way to think about kind of,
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01:53:33.520
if we sort of parse the universe down at the level of atoms of space or something,
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01:53:38.640
could we say, well, so that's really a question of a different point of view,
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01:53:42.080
a different place in real space. We're asking, you're asking the question,
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01:53:45.440
could there be a civilization that exists? Could there be sort of conscious entities
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01:53:52.480
that exist at the level of atoms of space? And what would that be like?
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01:53:56.080
And I think that comes back to this question of, can we, you know, what's it like to be a cellular
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01:53:59.520
automaton type thing? I mean, it's, you know, I'm not yet there. I don't know.
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01:54:06.000
I mean, I think that this is a, and I don't even know yet quite how to think about this
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01:54:12.800
in the sense that I was considering, you know, I'm, I never write fiction,
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01:54:16.560
but I haven't written it since I was like 10 years old. And my fiction, I made one attempt,
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01:54:20.640
which I sent to some science fiction writer friends of mine, and they told me it was terrible.
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01:54:24.160
So the bedtime... This is a long time ago?
link |
01:54:26.720
No, it was recently. Recently. They said it was terrible. That'd be
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01:54:29.680
interesting to see you write a short story based on what sounds like it's already inspiring
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01:54:34.640
short stories by, or stories by science fiction writers.
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01:54:38.640
But, but I think the interesting thing for me is, you know, in the, what does it,
link |
01:54:43.440
what is it like to be a whatever? How do you describe that? I mean, it's like,
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01:54:47.440
that's not a thing that you describe in mathematics, that what is it like to be such and such?
link |
01:54:51.760
Well, see, to me, when you say, what is it like to be something presumes that you're talking about
link |
01:54:58.000
a singular entity? So, yeah, like there's some kind of feeling of the entity, the stuff that's
link |
01:55:10.000
inside of it and the stuff that's outside of it. And then that's when consciousness starts making
link |
01:55:15.840
sense. But, but then it seems like that could be generalizable. If you take some subset of
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01:55:24.000
a cellular automata, you could start talking about what does that subset
link |
01:55:29.600
may feel. But then you can, I think you could just take arbitrary numbers of subsets. Like,
link |
01:55:35.840
to me, like you and I individually are consciousnesses, but you could also say
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01:55:43.280
the two of us together is a singular consciousness. Maybe, maybe, I'm not so sure about that. I think
link |
01:55:48.320
that the single thread of time thing may be pretty important. And that as soon as you start saying,
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01:55:53.280
there are two different threads of time, there are two different experiences. And then we have to
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01:55:58.160
say, how do they relate? How are they sort of entangled with each other? I mean, that may be a
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01:56:02.320
different story of a thing that isn't much like, what are the ants? What's it like to be an ant,
link |
01:56:09.360
where there's a sort of more collective view of the world, so to speak? I don't know. I think that,
link |
01:56:14.400
I mean, this is, I don't really have a good, I mean, my best thought is, can we turn it
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01:56:24.080
into a human story? It's like the question of, when we try and understand physics, can we turn
link |
01:56:29.280
that into something which is sort of a human understandable narrative? And now what's it
link |
01:56:33.120
like to be a such and such? Maybe the only medium in which we can describe that is something like
link |
01:56:38.880
fiction, where it's kind of like you're telling the life story in that setting. But this is
link |
01:56:47.280
beyond what I've yet understood how to do. Yeah, but it does seem so like with human consciousness,
link |
01:56:53.120
we're made up of cells. And there's a bunch of systems that are networked that work together
link |
01:57:01.120
that at this, at the human level, feel like a singular consciousness when you take,
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01:57:06.640
yes. And so maybe like an ant colony is just too low level. Sorry, an ant is too low level.
link |
01:57:13.840
Maybe you have to look at the ant colony. Yeah, I agree. There's some level at which
link |
01:57:19.040
it's a conscious being. And then if you go to the planetary scale, then maybe that's going too far.
link |
01:57:23.840
So there's a nice sweet spot for consciousness. No, I agree. I think the difficulty is that,
link |
01:57:30.320
you know, okay, so in sort of people who talk about consciousness, one of the terrible things
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01:57:36.960
I've realized, because I've now interacted with some of this community, so to speak,
link |
01:57:40.800
some interesting people who do that kind of thinking. But one of the things I was saying
link |
01:57:46.000
to one of the leading people in that area, I was saying that it must be kind of frustrating,
link |
01:57:53.840
because it's kind of like a poetry story. That is, many people are writing poems,
link |
01:57:57.200
but few people are reading them. So they're always these different, you know,
link |
01:58:00.960
everybody has their own theory of consciousness, and they are very non inter sort of interdiscussable.
link |
01:58:08.080
And by the way, I mean, you know, my own approach to sort of the question of consciousness,
link |
01:58:13.600
as far as I'm concerned, I'm an applied consciousness operative, so to speak, because
link |
01:58:17.840
I don't really, in a sense, the thing I'm trying to get out of it is how does it help me to understand
link |
01:58:23.280
what's a possible theory of physics? And how does it help me to say, how do I go from this
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01:58:29.520
incoherent collection of things happening in the universe to our definite perception and
link |
01:58:34.560
definite laws and so on, and sort of an applied version of consciousness. And I think the reason
link |
01:58:39.920
that sort of segues to a different kind of topic, but the reason that one of the things I'm
link |
01:58:44.400
particularly interested in is kind of what's the analog of consciousness in systems very different
link |
01:58:49.040
from brains. And so why does that matter? Well, you know, this whole description of this kind of
link |
01:58:56.400
well, actually, you know what, we haven't talked about why the universe exists. So let's let's
link |
01:58:59.920
get to why the universe exists. And then we then we can can talk about perhaps a little bit about
link |
01:59:05.360
what these models of physics kind of show you about other kinds of things like molecular computing
link |
01:59:11.280
and so on. Yes, that's good. Why does the universe exist? Okay, so we finally sort of more or less
link |
01:59:16.400
set the stage, we've got this idea of this really add of this object that is made from following all
link |
01:59:21.600
possible rules, the fact that it's sort of not just this incoherent mess, it's got all this
link |
01:59:26.960
entangled structure in it, and so on. Okay, so what is this really add? Well, it is the working out
link |
01:59:35.200
of all possible formal systems. So the sort of a question of why does the universe exist? It's
link |
01:59:41.200
core question, you kind of started with is, you've got two plus two equals four, you've got some other
link |
01:59:47.200
abstract results. But that's not actualized. It's just an abstract thing. And when we say we've
link |
01:59:53.200
got a model for the universe, okay, it's this rule, you run it, and it'll make the universe. But it's
link |
01:59:57.520
like, but, but, you know, where's it actually running? What, what, what is what is it actually
link |
02:00:03.440
doing? Right? What is is it actual? Or is it merely a formal description of something? Okay.
link |
02:00:09.760
So the thing to realize with this, with this, the thing about the rule yard is it's an inevitable,
link |
02:00:15.760
it is the entangled running of all possible rules. So you don't get to say it's not like you're saying,
link |
02:00:22.960
which rule yard are you picking? Because it's all possible formal rules. It's not like it's just,
link |
02:00:30.000
you know, well, actually, it's only footnote, the only footnote, it's an important footnote,
link |
02:00:34.880
is it's all possible computational rules, not hyper computational rules. That is,
link |
02:00:42.000
it's running all the rules that would be accessible to a Turing machine, but is not running all the
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02:00:50.160
rules that will be accessible to a thing that can solve problems in finite time that would take a
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02:00:54.960
Turing machine infinite time to solve. So you can even Alan Turing knew this that you could make
link |
02:01:00.080
oracles for Turing machines where you say, a Turing machine can't solve the whole thing problem
link |
02:01:04.160
for Turing machines, it can't know what will happen in any Turing machine after an infinite time
link |
02:01:09.040
in any finite time, but you could invent a box, just make a black box, you say, I'm going to sell
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02:01:14.480
you an oracle that will just tell you, you know, press this button, it'll tell you what the Turing
link |
02:01:19.040
machine will do after an infinite time, you can imagine such a box, you can't necessarily build
link |
02:01:23.680
one in the physical universe, but you can imagine such a box. And so we could say, well, in addition
link |
02:01:28.720
to, so in this Ruliad, we're imagining that there is a computational that at the end,
link |
02:01:35.520
it's, it's running rules that are computational. It doesn't have a bunch of
link |
02:01:40.080
oracle black boxes in it. You say, well, why not? Well, turns out if there are oracle black boxes,
link |
02:01:47.120
the Ruliad that is, you can make a sort of super Ruliad that contains those oracle black boxes,
link |
02:01:53.040
but it has a cosmological event horizon relative to the first one, they can't communicate.
link |
02:01:57.360
In other words, you can, you can end up with what you end up happening, what ends up happening is
link |
02:02:03.440
it's, it's, it's like in the physical universe, we, in this causal graph that represents the causal
link |
02:02:08.320
relationships of different things, you can have an event horizon, where there's, where the causal
link |
02:02:12.960
graph is disconnected, where the effect here, an event happening here does not affect an event
link |
02:02:18.800
happening here, because there's a disconnection in the causal graph. And that's what happens in an
link |
02:02:22.960
event horizon. And so what will happen between this kind of the ordinary Ruliad and the hyper Ruliad
link |
02:02:30.240
is there is an event horizon, and you, you know, we in our Ruliad will just never know that there
link |
02:02:38.800
is, that they're just separate things. They're not, they're not connected.
link |
02:02:43.040
Maybe I'm not understanding, but just because we can't observe it,
link |
02:02:46.000
why does that mean it doesn't exist? It might exist, but it does, it's not clear what it,
link |
02:02:53.840
it's so what, so to speak, whether it exists. You know, what we're trying to understand is why
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02:02:58.480
does our universe exist? We're not trying to ask the question what, you know, it's,
link |
02:03:05.120
let me say another thing, let me make a meta comment, okay, which is that, that I have not
link |
02:03:10.640
thought through this hyper Ruliad business properly. So I can't, the hyper Ruliad is referring to
link |
02:03:19.760
a Ruliad in which hyper computation is possible. That's correct. Okay. So like what the, that foot
link |
02:03:25.840
note, the footnote to the footnote is we're not sure why this is important. Yeah, that's right.
link |
02:03:34.160
So let's, let's ignore that. Okay. It's already abstract enough. Okay. So, so, okay. So the one
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02:03:41.120
question is, we have to say, if we're saying, why does the universe exist? One question is,
link |
02:03:47.440
why is it this universe and not another universe? Yeah. Okay. So the important point about this
link |
02:03:52.800
Ruliad idea is that it's in the Ruliad are all possible formal systems. So there's no choice
link |
02:04:00.160
being made. There's no, there's no like, oh, we picked this particular universe and not that one.
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02:04:05.120
That's the first thing. The second thing is the that we have to ask the question. So, so you say,
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02:04:11.760
why does two plus two equals four exist? That's not really a that is a thing that necessarily
link |
02:04:18.400
is that way, just on the basis of the meaning of the terms two and plus and equals and so on.
link |
02:04:23.760
Right. So the thing is that this, this Ruliad object is in a sense a necessary object. It is
link |
02:04:31.280
just the thing that is the consequence of working out the consequence of the formal definition of
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02:04:37.120
things. You don't, it is not a thing where you're saying, and this is picked as the particular
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thing. This is just something which necessarily is that thing because of the definition of what
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it means to have computation. So it's a Ruliad. It's a formal system. Yes.
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But does it exist? Ah, well, where are we in this whole thing? We are part of this Ruliad.
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And so our, so there is no sense to say, does two plus two equals four exist? Well, that's,
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that's in some sense, it necessarily exists. It's a necessary object. It's not a thing that
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where you can ask, you know, it's, it's usually in philosophy, there's a sort of distinction
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made between, you know, necessary truths, contingent truths, analytic propositions,
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synthetic propositions, there are a variety of different versions of this. They're things which
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are necessarily true, just based on the definition of terms. And there are things which happen to
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be true in our universe. But we're weird, we don't exist in Rulial space. We, that's one of the
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coordinates that define our existence, right? Well, okay, so, so yes, yes, but this Ruliad
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is the set of all possible Rulial coordinates. So what we're saying is it contains that. So what
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we're saying is we exist as, okay, so our perception of what's going on is we're at a particular
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place in this Ruliad. And we are concluding certain things about how the universe works
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based on that. But the question is, do we understand, you know, is there something where we say,
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so, so why does it work that way? Well, the answer is, I think it has to work that way,
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because this, there isn't, this Ruliad is a necessary object in the sense that it is a purely
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formal object, just like two plus two equals four. It's not an object that was made of something. It's
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an object that is just an expression of the necessary collection of formal relations that exist.
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And so then the issue is, can we, in our experience of that, is it, you know, can we have tables and
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02:06:54.640
chairs, so to speak, in that just by virtue of our experience of that necessary thing?
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And, you know, what people have generally thought, and also that I don't know of a lot of
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discussion of this, why does the universe exist question? It's been a very, you know,
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I've been surprised actually at how little, I mean, I think it's one of these things that's
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really kind of far out there. But the thing that that is, you know, the surprise here is that
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all possible formal rules, when you run them together, and that's the critical thing,
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02:07:28.880
when you run them together, they produce this kind of entangled structure that has a definite
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structure. It's not just, you know, a random arbitrary thing, it's a thing with definite
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structure. And that structure is the thing when we are embedded in that structure, when anything,
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you know, the an entity embedded in that structure perceives something, which is,
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then we can interpret as physics and things like this. So in other words, we don't have to ask the
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question, the why does it exist? It necessarily exists. I'm missing this part. Why does it
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02:08:02.720
necessarily exist? Okay, okay. So like you need to have it if you want to formalize the relation
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02:08:10.400
between entities, but why do you need to have relations? Okay, okay. So let's say you say,
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well, it's like, why does math have to exist? Okay, that's the question. Yeah, okay, fair question.
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Let's see. I think the thing to think about is the existence of mathematics is something where,
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given a definition of terms, what follows from that definition inevitably follows.
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So now you can say, why define any terms? But in a sense, the, well, that's okay. So the definition
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of terms, I mean, I think the way to think about this, let me see. So like, concrete terms?
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02:09:02.800
Well, that's not very concrete. I mean, they're just things like, you know,
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logical or right. But that's a thing. That's a powerful thing.
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02:09:13.920
Well, it's a, yes, okay. But it's a, the point is that it is not a thing about,
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people imagine there is, I don't know, the, an elephant or something or the,
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elephants are presumably not necessary objects. They happen to exist as a result of kind of
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02:09:34.480
biological evolution and whatever else. But the, the thing is that in some sense, that there is,
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02:09:42.160
it is a different kind of thing to say, does plus exist? The, it is not, it's not, not like an
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elephant. So a plus is, seems more fundamental, more basic than an elephant. Yes. But you can
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imagine a world without plus or anything like it. Like why do formal things that are discreet, that
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02:10:05.200
can be used to reason have to exist? Well, okay. So why, okay. So then the question is,
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but the whole point is computation, we can certainly imagine computation. That is,
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we can certainly say there is a formal system that we can construct abstractly in our minds
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02:10:24.720
that is computation. And that, that's the, and you know, we can, we can imagine it, right? Now,
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the question is, is it is that formal system, once we exist as observers embedded in that
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02:10:40.480
formal system, that's enough to have something which is like our universe. And so then the,
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then what you're kind of asking is, perhaps, is why, I mean, the point is we definitely
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can imagine it. There's nothing that says that we're not saying that there's, it's sort of inevitable
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that, that is a thing that we can imagine. We don't have to ask, does it exist? We're just,
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02:11:07.040
it is definitely something we can imagine. Now that's, then we have this thing that is
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a formally constructible thing that we can imagine. And now we have to ask the question,
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what, you know, given that formally constructible thing, what is, what consequences does that,
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02:11:26.000
if we were to perceive that formally, if we were embedded in that formally constructible thing,
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what would be perceived about the world? And we would say, we perceive that the world exists,
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02:11:38.400
because we are, we are seeing all of this mechanism of all these things happening. And,
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but that's something that is just a feature of, it's, it's, it's something where we are, see,
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another way of asking this that I'm trying to get at, I understand why it feels like this
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02:11:56.240
rulliad is necessary. But maybe it's just me being human, but it feels like then
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you should be able to, not us, but somehow step outside of the rulliad. Like what's
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02:12:12.160
outside the rulliad? Well, the rulliad is all formal systems. So there's nothing, because
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But that's what a human would say. I know that's what a human would say, because we're used to
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the idea that there are, there's, but the whole point is that by the time it's all possible,
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formal systems, it's, it's like, it is all things you can imagine. But no, all computations you can
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02:12:36.000
imagine. But like, we don't, well, so that could be a code. Okay. So, so that's a, that's a fair
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02:12:43.280
question. Is it possible to encode all, I mean, once we, is, is there something that isn't what
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02:12:51.760
we can represent formally? Right. That is, that is, there's something that, and that's, I think,
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related to the hyper rulliad footnote, so to speak, which I'm afraid that the, you know,
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02:13:04.160
one of the things sort of interesting about this is, you know, there has been some discussion of
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this in theology and things like that. But, which I don't necessarily understand all of.
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But the, the key sort of new input is this idea that all possible formal systems, it's like,
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you know, if you make a world, people say, well, you make a world with a particular, in a particular
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way, with particular rules, but no, you don't do that. You can make a world that deals with all
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possible rules, and then merely by virtue of living in a particular place in that world,
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02:13:41.280
so to speak, we have the perception we have of, of what the world is like. Now, I have to say,
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02:13:48.320
it's sort of interesting because I've, you know, I wrote this piece about this, and I, you know,
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02:13:53.200
this philosophy stuff is not super easy. And I've, as I'm, as I'm talking to you about it,
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and I actually haven't, you know, people have been interested in lots of different things we've
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02:14:02.880
been doing, but this, why does the universe exist has been, I would say, one of the, one of the
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ones that you would think people will be most interested in. But actually, I think they're
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02:14:12.560
just like, oh, that's just something complicated. So, so I haven't, I haven't explained it as,
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as much as I've explained a bunch of other things. And I have to say, I think I,
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02:14:22.400
I think I may be missing a couple of pieces of that argument that would be so, so it's kind of a
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02:14:28.880
like, well, you're, you're conscious being is computationally bounded. So you're missing,
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02:14:34.880
having written quite a few articles yourself, you, you're now missing some of the pieces.
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02:14:40.400
Yes, right. The limitation of being human. Right. One of the consequences of this,
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02:14:44.800
why the, why the universe exists thing and this kind of concept of Rulee ads and, and, you know,
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02:14:51.600
places in there representing our perception of the universe and so on, one of the weird
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02:14:56.080
consequences is, if the universe exists, mathematics must also exist. And that's a weird
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02:15:03.440
thing because mathematics, people have been very confused, including me, have been very confused
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02:15:08.880
about the, the, the question of, of kind of what, what is the foundation of mathematics,
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02:15:15.440
what is, what kind of a thing is mathematics is mathematics, something where we just write down
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02:15:20.800
axioms like Euclid did for geometry and we just build the structure and we could have written
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02:15:25.440
down different axioms and we'd have a different structure. Or is it something that has a more
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02:15:29.760
fundamental sort of truth to it? And I have to say it's one of these cases where I've, I've long
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02:15:35.200
believed that mathematics has a great deal of arbitraryness to it, that there are particular
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02:15:38.800
axioms that kind of got written down by the Babylonians. And, you know, that's what we've
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02:15:43.680
ended up with the mathematics that we have. And I have to say, actually, my, my wife has been telling
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02:15:48.160
me for 25 years, she was a mathematician, she's been telling me, you're wrong about the foundations
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02:15:52.640
of mathematics. And, and, you know, I'm like, no, no, no, I know what I'm talking about. And
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02:15:58.000
finally, she's, she's much more right than, than I've been. So it's, it's one of the.
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02:16:03.760
So I mean, her sense, in your sense, are we just, so this is to the question of metamath,
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02:16:10.560
mathematics, are we just kind of on a trajectory through
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02:16:14.000
through rural space, except in mathematics, through a trajectory of certain kind of
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02:16:19.360
I think that's partly the idea. So I think that the notion is this. So 100 years ago,
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02:16:24.320
a little bit more than 100 years ago, what people have been doing mathematics for ages,
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02:16:28.080
but then in the, in the late 1800s, people decided to try and formalize mathematics and say, you
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02:16:33.920
know, it is mathematics is, you know, we're going to break it down, we're going to make it like
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02:16:38.080
logic, we're going to make it out of, out of sort of fundamental primitives. And that was people
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02:16:42.480
like Frager and piano and Hilbert and so on. And they kind of got this idea of let's do kind of
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02:16:48.640
Euclid, but even better, let's just make everything just in terms of this sort of symbolic axioms,
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02:16:53.920
and then build up mathematics from that. And that, you know, they thought at the time,
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02:16:59.280
as soon as they get these symbolic axioms that they made the same mistake, the kind of computational
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02:17:04.480
irreducibility mistake, they thought as soon as we've written down the axioms, then it'll just
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02:17:10.000
we'll just have a machine, kind of a supermathematica, so to speak, that can just grind out all true
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02:17:15.840
theorems of mathematics. That got exploited by Goedl's theorem, which is basically the story
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02:17:21.120
of computational irreducibility. It's that even though you know those underlying rules,
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02:17:25.760
you can't deduce all the consequences in any finite way. And so, so that was, but now the question
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02:17:31.600
is, okay, so they broke mathematics down into these axioms. And they say now you build up from
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02:17:36.880
that. So what I'm increasingly coming to realize is, that's similar to saying, let's take a gas
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02:17:44.080
and break it down into molecules. There's gas laws that are the large scale structure and so on,
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02:17:50.160
that we humans are familiar with. And then there's the underlying molecular dynamics. And I think
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02:17:55.120
that the axiomatic level of mathematics, which we can access with automated theorem proving and
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02:18:00.160
proof assistance, and these kinds of things, that's the molecular dynamics of mathematics.
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02:18:05.200
And occasionally we see through to that molecular dynamics. We see undecidability, we see other
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02:18:10.560
things like this. One of the things I've always found very mysterious is that Goedl's theorem
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02:18:15.440
shows that there are sort of things which cannot be finitely proved in mathematics. There are proofs
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02:18:20.880
of arbitrary length, infinite length proofs that you might need. But in practical mathematics,
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02:18:25.920
mathematicians don't typically run into this. They just happily go along doing their mathematics.
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02:18:31.280
And I think what's actually happening is that what they're doing is they're looking at this,
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02:18:36.480
they are essentially observers in metamathematical space. And they are picking a reference frame
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02:18:43.760
in metamathematical space. And they are computationally bounded observers in metamathematical space,
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02:18:49.200
which is causing them to deduce that the laws of metamathematics and the laws of mathematics,
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02:18:55.600
like the laws of fluid mechanics, are much more understandable than this underlying molecular dynamics.
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02:19:01.760
And so what gets really bizarre is thinking about kind of the analogy between metamathematics,
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02:19:08.560
this idea of you exist in this kind of, in this sort of space of possible, in this kind of
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02:19:16.960
mathematical space where the individual kind of points in the mathematical space are statements
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02:19:23.280
in mathematics, and they're connected by proofs, where one statement, you know, you take a couple
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02:19:28.000
of different statements, you can use those to prove some other statement, and you've got this
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02:19:31.600
whole network of a proofs, that's the kind of causal network of mathematics of what can prove
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02:19:36.720
what and so on. And you can say at any moment in the history of a mathematician, of a single
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02:19:43.360
mathematical consciousness, you are in a single kind of slice of this kind of metamathematical
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02:19:50.800
space, you know a certain set of mathematical statements, you can then deduce with proofs,
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02:19:55.760
you can deduce other ones, and so on, you're kind of gradually moving through metamathematical space.
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02:20:01.040
And so it's kind of the view is that the reason that mathematicians perceive mathematics to have
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02:20:07.120
the sort of integrity and lack of kind of undecidability and so on that they do is because
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02:20:12.080
they like we as observers of the physical universe, we have these limitations associated with
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02:20:17.600
computational boundedness, single thread of time, consciousness limitations basically,
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02:20:22.160
that the same thing is true of mathematicians perceiving sort of metamathematical space.
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02:20:26.320
And so what's happening is that when you look at, if you look at one of these formalized
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02:20:30.560
mathematics systems, something like, you know, Pythagoras's theorem, it'll be, it'll take,
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02:20:35.920
oh, I don't know, what is it, maybe 10,000 individual little steps to prove Pythagoras's
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02:20:42.400
theorem. And one of the bizarre things that's sort of an empirical fact that I'm trying to
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02:20:47.200
understand a little bit better, if you look at different proof, if you look at different
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02:20:50.960
formalized mathematics systems, they actually have different axioms underneath that they can all
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02:20:55.520
prove Pythagoras's theorem. And so in other words, it's a little bit like what happens with gases,
link |
02:21:00.960
we can have air molecules, we can have water molecules, but they still have fluid dynamics,
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02:21:04.960
both of them have fluid dynamics. And so similarly, at the level that mathematics,
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02:21:09.280
that mathematicians care about mathematics, it's way above the molecular dynamics, so to speak.
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02:21:14.560
And they're all kinds of weird things, like for example, one thing I was realizing recently is
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02:21:18.320
that the quantum theory of mathematics, that's a very bizarre idea. But basically, when you prove,
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02:21:24.800
what is, you know, a proof is you've got one statement in mathematics, you go through other
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02:21:29.680
statements, you eventually get to a statement you're trying to prove, for example, that's a path,
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02:21:34.080
path in metamathematical space. And that's a single path, a single proof is a single path.
link |
02:21:39.120
But you can imagine, there are other proofs of the same results. They're a bundle of proofs.
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02:21:44.960
There's this whole set of possible proofs.
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02:21:47.200
You could think of as branching, similar to the quantum mechanics model that you were talking
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02:21:50.880
about. Exactly. And so then there's some invariance that you can formalize in the same way that you
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02:21:55.360
can for the quantum mechanical. Right. So the question is in proof space,
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02:21:59.040
you know, as you start thinking about multiple proofs, are there analogs of, for example,
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02:22:02.880
destructive interference of multiple proofs? So here's a bizarre idea. It's just a couple of
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02:22:07.760
days old, so not yet fully formed. But as you try and do that, when you have two different proofs,
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02:22:14.240
it's like two photons going in different directions, you have two proofs which at an
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02:22:17.520
intermediate stage are incompatible. And that's kind of like destructive interference.
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02:22:22.000
Is it possible for this to instruct the engineering of automated proof systems?
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02:22:28.000
Absolutely. I mean, it's a practical matter. I mean, this whole question, in fact, Jonathan
link |
02:22:32.800
Gorat has a nice heuristic for automated theorem provers that's based on our physics project
link |
02:22:37.760
that is looking for essentially using kind of using energy and in our models, energy is kind of
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02:22:46.160
level of activity in this hypergraph. And so there's sort of a heuristic for automated theorem
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02:22:51.920
proving about how do you pick which path to go down that is based on essentially physics.
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02:22:58.640
And I mean, the thing that gets interesting about this is, is the way that one can sort of have
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02:23:02.880
the interplay between like, for example, a black hole, what is a black hole in mathematics?
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02:23:07.840
So the answer is, what is black hole in physics? A black hole in physics is where,
link |
02:23:12.880
in the simplest form of black hole, time ends. That is all, you know, everything is crunched
link |
02:23:18.560
down to the spacetime singularity, and everything just ends up at that singularity. So in our models,
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02:23:24.560
and that's a little hard to understand in general relativity with continuous mathematics and what
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02:23:28.560
does singularity look like? In our models, it's something very pragmatic. It's just,
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02:23:32.560
you're applying these rules, time is moving forward. And then there comes a moment where the rules,
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02:23:37.040
no rules apply. So time stops. It's kind of like the universe dies. The, you know, the,
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02:23:42.480
the nothing happens in the universe anymore. Well, in mathematics, that's a decidable theory.
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02:23:48.000
That's a theory. So theories which have undecidability, which are things like arithmetic,
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02:23:52.640
set theory, all the serious models, theories in mathematics, they all have the feature that
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02:23:57.280
there are proofs of arbitrary long length. And something like Boolean algebra, which is a decidable
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02:24:02.560
theory, there are, you know, any question in Boolean algebra, you can just go crunch, crunch,
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02:24:06.880
crunch, and in a known number of steps, you can answer it. You know, satisfiability, you know,
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02:24:12.320
might be hard, but it's still a bounded number of steps to answer any satisfiability problem.
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02:24:17.120
And so that's the notion of a black hole in physics where time stops. That's the,
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02:24:23.520
that's analogous to in mathematics, where there aren't infinite length proofs, where when in
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02:24:29.120
physics, you know, you can wander around the universe forever, if you don't run into a black
link |
02:24:33.920
hole, if you run into a black hole and time stops, you're done. And it's the same thing in
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02:24:38.480
mathematics between decidable, decidable theories and undecidable theories. That's a,
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02:24:42.400
that's an example. And I think we're sort of the, the, the attempt to understand. So, so another
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02:24:47.440
question is kind of what is the, what is the generativity of, of metamathematics? What is the
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02:24:53.840
bulk theory of metamathematics? So in the literature of mathematics, there are about 3 million
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02:24:58.800
theorems that people have, have published. And those represent, it's kind of on this, it's like,
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02:25:04.240
like on the earth, we would be, you know, you know, we've put cities in particular places on the
link |
02:25:09.840
earth. But yet there is ultimately, you know, we know the earth is roughly spherical, and there's
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02:25:14.560
an underlying space. And we could just talk about, you know, the world of space in terms of where
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02:25:20.160
our cities happen to be, but there's actually an underlying space. And so the question is, what's
link |
02:25:24.240
that for metamathematics? And as we kind of explore what is, for example, for mathematics,
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02:25:28.960
which is always likes taking sort of abstract limits. So an obvious abstract limit for
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02:25:33.920
mathematics to take is the limit of the future of mathematics. That is, what is the limit of
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02:25:39.360
what will be, you know, the ultimate structure of mathematics. And one of the things that's
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02:25:44.000
an empirical observation about mathematics, that's quite interesting is that a lot of theories in
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02:25:49.280
one area of mathematics algebraic geometry or something might have, they play into another
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02:25:54.240
area of mathematics, that that same the same kind of a fundamental construct seem to occur
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02:26:00.160
in very different areas of mathematics. And that structurally captured a bit with category theory
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02:26:04.560
and things like that. But I think that there's probably an understanding of this metamathematical
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02:26:09.120
space that will explain why different areas of mathematics ultimately sort of map into the same
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02:26:14.640
thing. And I mean, you know, my little challenge to myself is what's time dilation in, in metamathematics?
link |
02:26:21.920
In other words, as you, as you basically as you move around in this mathematical space of possible
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02:26:27.440
statements, you know, what's how does that moving around? It's basically what's happening is that
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02:26:33.920
as you move around in the space of mathematical statements, it's like you're changing from
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02:26:37.200
algebra to geometry to whatever else. And you're trying to prove the same theorem. But as you try,
link |
02:26:43.040
if you keep on moving to these different places, it's slower to prove that theorem because you
link |
02:26:47.440
keep on having to translate what you're doing back to where you started from. And that's kind of the
link |
02:26:51.120
beginnings of the analog of time dilation in mathematics. Plus there's probably fractional
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02:26:56.000
dimensions in this space as well. Oh, this space is a very messy space. This space is much messier
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02:27:01.920
than physical space. I mean, even in, even in the models of physics, physical space is very tame
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02:27:07.840
compared to branchial space and rural space. I mean, the mathematical structure, you know,
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02:27:12.880
branchial space is probably more like Hilbert space, but it's a rather complicated Hilbert space.
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02:27:17.200
And rural space is more like this weird infinity groupoid story of growth and deacon. And, you
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02:27:24.400
know, I can explain that a little bit because in, you know, in, in metamathematical space,
link |
02:27:29.040
a, a path in metamathematical space is a, is a, a path between two statements is a way to get by
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02:27:36.320
proofs is to way to find a proof that goes from one statement to another. And so one of the things
link |
02:27:42.160
you can do, you can think about is you've got between statements, you've got proofs, and they
link |
02:27:46.640
are paths between statements. Okay. So now you can go to the next level and you can ask, what about
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02:27:51.840
a mapping from one proof to another? And so that's in, in category theory, that's kind of a higher
link |
02:27:57.360
category that notion of higher categories where you're, where you're mapping not just between,
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02:28:02.560
not just between objects, but you're mapping between the mappings between objects and so on.
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02:28:07.360
And so you can keep doing that. You keep saying higher order proofs. I want
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02:28:11.440
mappings between proofs, between proofs and so on. And that limiting structure. Oh, by the way,
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02:28:16.160
one thing that's very interesting is imagine in proof space, you've got these two proofs.
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02:28:21.200
And the question is, what is the topology of proof space? In other words, if you take these two
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02:28:25.760
paths, can you continuously deform them into each other? Or is there some big hole in the middle
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02:28:30.880
that prevents you from continuously deforming them one into the other? It's kind of like,
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02:28:34.800
you know, when you, when you think about some, I don't know, some puzzle, for example, you're
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02:28:38.480
moving pieces around on some puzzle, and you can think about the space of possible states of the
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02:28:43.360
puzzle. And you can make this graph that shows from one state of the puzzle to another state of
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02:28:47.680
the puzzle and so on. And sometimes you can easily get from one state to any other state,
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02:28:52.400
but sometimes there'll be a hole in that space. And there'll be, you know, you always have to
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02:28:56.720
go around the circuitous route to get from here to there. There won't be any direct way.
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02:29:01.680
And that's kind of a question of, of whether there's sort of an obstruction in the space.
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02:29:06.640
And so the question is in proof space, what is the, what are, you know, what does it mean if
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02:29:12.720
there's an obstruction in proof space? Yeah, I don't even know what an obstruction means in
link |
02:29:17.360
proof space, because for it to be an obstruction, it should be reachable some other way from some
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02:29:22.640
other place, right? So this is like an unreachable part of the graph.
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02:29:27.760
No, it's not just an unreachable part. It's a part where there are paths that go one way,
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02:29:31.920
there are paths that go the other way. And this question of homotopy and mathematics is this
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02:29:35.760
question, can you continuously deform, you know, from one path to another path? Or do you have to
link |
02:29:40.880
go in a jump, so to speak? So it's like, if you're going around a sphere, for example, if you're
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02:29:45.120
going around a, I don't know, a cylinder or something, you can wind around one way. And you
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02:29:50.400
can, there's no, the paths where you can, where you can easily deform one path into another,
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02:29:55.360
because it's just sort of sitting on the same side of the cylinder. But when you've got something
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02:29:58.960
that winds all the way around a cylinder, you can't continuously deform that down to a point,
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02:30:03.280
because it's stuck wrapped around. Well, my intuition about proof space is you should be
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02:30:07.360
able to deform it. I mean that, because then otherwise it doesn't even make sense. Because
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02:30:10.880
if the topology matters of the way you move about the space, then I don't even know what
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02:30:16.560
that means. Well, what it would mean is that you would have one way of doing a proof of something
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02:30:21.840
over here in algebra, and another way of doing a proof of something over here in geometry,
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02:30:26.560
and there would not be an intermediate way to map between those proofs.
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02:30:30.800
But how would that be possible if they started the same place and ended the same place?
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02:30:35.120
Well, it's the same thing as, you know, we've got points on a, you know, if we've got paths on
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02:30:40.160
a cylinder. I understand how it works in physical space, but it just doesn't, it feels like proof
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02:30:45.200
space shouldn't have that. Okay, I mean. I'm not sure. I don't know. We'll know very soon,
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02:30:50.560
because we get to do some experiments. This is the great thing about this stuff,
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02:30:53.760
is that in fact, you know, in the next few days, I hope to do a bunch of experiments on this.
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02:30:58.800
So you're playing like proofs in this kind of space? Yes. Yes. I mean, so, you know, this is toy,
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02:31:05.200
you know, theories, and, you know, we've got good, so this kind of segues to perhaps another thing,
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02:31:10.400
which is this whole idea of multi computation. So this, this is another kind of bigger idea that,
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02:31:18.320
so, okay, this has to do with how do you make models of things? And it's going to, it's, so
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02:31:25.760
I've sort of claimed that they've been sort of four epochs in the history of making models of
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02:31:30.560
things. And, and this multi computation thing is, is the fourth is a new epoch.
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02:31:36.320
What are the first three? The first one is, is back in antiquity, ancient Greek times, people were
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02:31:42.960
like, what's the universe made of? Oh, it's made of, you know, everything is water, Thales, you know,
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02:31:48.240
or everything is made of atoms. It's sort of what are things made of, or the, you know, there are
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02:31:54.080
these crystal spheres that represent where the planets are and so on. It's like a structural
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02:31:59.200
idea of how the universe is constructed. There's no real notion of dynamics. It's just what is the
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02:32:04.320
universe? How is the universe made? Then we get to the 1600s, and we get to the sort of revolution
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02:32:10.000
of mathematics being introduced into physics. And then we have this kind of idea of you write down
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02:32:16.880
some equation, the what happens in the universe is the solving of that equation, time enters,
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02:32:23.680
but it's usually just a parameter, we just can, you know, sort of slide it back and forth and say,
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02:32:28.480
here's where it is. Okay, then we come to this kind of computational idea that I kind of started
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02:32:35.280
really pushing in the early 1980s. As a result, you know, the things we were talking about before
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02:32:40.400
about complexity, that was my motivation. But the biggest story was the story of kind of computational
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02:32:46.160
models of things. And the big difference there from the mathematical models is in mathematical
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02:32:51.360
models, there's an equation, you solve it, you got kind of slide time to the place where you want it.
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02:32:56.320
In computational models, you give the rule, and then you just say, go run the rule. And time is not
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02:33:03.360
something you get to slide. Time is something where it just you run the rule, time goes in steps.
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02:33:09.600
And that's how you work out what how the system behaves, you don't time is not just a parameter.
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02:33:14.720
Time is something that is about the running of these of these rules. And so there's this computational
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02:33:20.000
irreducibility, you can't jump ahead in time. But there's still important thing is there's still
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02:33:25.040
one thread of time. It's still the case, you know, the cellular automaton state, then it has the next
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02:33:30.160
state and the next state and so on. The thing that is kind of we've sort of tipped off by quantum
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02:33:35.280
mechanics, in a sense, although it actually feeds back even into durability and things like that,
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02:33:40.800
that there are these multiple threads of time. And so in this multi computation paradigm, the
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02:33:46.240
kind of idea is, instead of there being the single thread of time, there are these kind of
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02:33:50.800
distributed asynchronous threads of time that are happening. And the thing that's sort of different
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02:33:55.920
there is, if you want to know what happened, if you say what happened in the system, in the case
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02:34:01.520
of the computational paradigm, you just say, well, after 1000 steps, we got this result. Right.
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02:34:08.320
But in the multi computational paradigm, after 1000 steps, not even clear what 1000 steps means,
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02:34:13.120
because you've got all these different threads of time. But there is no state. There's all these
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02:34:17.520
different possible, you know, there's all these different parts. And so the only way you can
link |
02:34:22.000
know what happened is to have some kind of observer who is saying here's how to parse the
link |
02:34:26.880
results of what was going on. Right. But that observer is embedded and they don't have a complete
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02:34:31.120
picture. So in the case of physics, that's right. Yes. And then in the, but that's, but so the idea
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02:34:36.560
is that in this multi computation setup, that it's this idea of these multiple threads of time,
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02:34:42.240
and models that are based on that. And this is similar to what people think about in non deterministic
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02:34:48.560
computation. So you have a Turing machine, usually it has a definite state, it follows another state,
link |
02:34:53.200
follows another state. But typically what people have done when they've thought about these kinds
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02:34:56.960
of things is they've said, well, there are all these possible paths and non deterministic Turing
link |
02:35:00.880
machine can follow all these possible paths. But we just want one of them, we just want the one
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02:35:05.200
that's the winner that factors the number or whatever else. And similarly, it's the same story
link |
02:35:10.160
in logic programming and so on. But we say we've got this goal, find us a path to that goal,
link |
02:35:15.200
I just want one path, then I'm happy. Or theorem proving same story, I just want one proof and
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02:35:20.080
then I'm happy. What's happening in multi computation in physics is we actually care about
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02:35:25.600
many paths. And well, there is a case for example, probabilistic programming is a version of
link |
02:35:30.880
multi computation in which you're looking at all the paths, you're just asking for probabilities of
link |
02:35:35.120
things. But in a sense in physics, we're taking different kinds of samplings. For example, in
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02:35:40.880
quantum mechanics, we're taking a different kind of sampling of all these multiple paths.
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02:35:45.920
But the thing that is notable is that when you are when you're an observer embedded in this thing,
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02:35:51.760
etc, etc, etc, with various other sort of footnotes and so on, it is inevitable that the thing that
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02:35:59.040
you parse out of this system looks like general activity and quantum mechanics. In other words,
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02:36:04.960
that just by the very structure of this multi computational setup, it inevitably is the case
link |
02:36:11.200
that you have certain emergent laws. Now, why is this perhaps not surprising? In thermodynamics
link |
02:36:19.040
and statistical mechanics, there are sort of inevitable emergent laws of sort of gas dynamics
link |
02:36:24.720
that are independent of the of the details of molecular dynamics, sort of the same kind of thing.
link |
02:36:29.920
But I think what happens is what's a sort of a funny thing that I just been understanding very
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02:36:34.640
recently is when when I kind of introduced this whole sort of computational paradigm complexity
link |
02:36:41.440
ish thing back in the 80s, it was kind of like a big downer, because it's like there's a lot of
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02:36:46.000
stuff you can't say about what systems will do. And then what I realized is and then you might say,
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02:36:51.040
now we've got multi computation, it's even worse, you know, it's isn't just one thread of time that
link |
02:36:55.360
we can't explain, it's all these threads of time, we can't explain anything. But the following thing
link |
02:37:00.080
happens, because there is all this irreducibility and any detailed thing you might want to answer,
link |
02:37:06.640
very hard to answer. But when you have an observer who has certain characteristics like computational
link |
02:37:12.640
boundedness, sequentiality of time and so on, that observer only samples certain aspects of this
link |
02:37:19.440
incredible complexity going on in this multi computational system. And that observer is sensitive
link |
02:37:25.040
only to some underlying core structure of this multi computational system. There is all this
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02:37:30.720
irreducible computation going on all these details. But to that kind of observer, what's
link |
02:37:35.920
important is only the core structure of multi computation, which means that observer observes
link |
02:37:42.560
comparatively simple laws. And I think it is inevitable that that observer observes laws which
link |
02:37:48.320
are mathematically structured like general relativity and quantum mechanics, which by the
link |
02:37:52.960
way, are the same law in our in our model of physics. So that's an explanation why there's
link |
02:37:57.840
simple laws that explain a lot for this observer. Potentially, yes. But what the place where this
link |
02:38:03.840
gets really interesting is there are all these fields of science where people have kind of gotten
link |
02:38:10.160
stuck where they say we'd really love to have a physics like theory of economics, we'd really
link |
02:38:14.960
love to have a physics like law and linguistics. You got to talk about molecular biology here.
link |
02:38:20.480
Okay. So where where where does multi computation come in for biology, economics is super
link |
02:38:25.280
interesting too, but biology. Okay, let's talk about that. So let's talk about chemistry for a
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02:38:28.880
second. Okay. So I mean, I have to say, you know, this is such a weird business for me because,
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02:38:34.160
you know, there are these kind of paradigmatic ideas and then the actual applications. And
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02:38:38.880
it's like I've always said, I know nothing about chemistry, I learned all the chemistry I know,
link |
02:38:42.560
you know, the night before some exam when I was 14 years old. But yeah, but I've actually learned
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02:38:46.320
a bunch more chemistry. And in more from language these days, we have really pretty nice symbolic
link |
02:38:50.560
representation of chemistry. And in understanding the design of that, I've actually I think learned
link |
02:38:55.200
a certain amount of chemistry. If you quizzed me on sort of basic high school chemistry,
link |
02:38:59.360
I would probably totally fail. But but but okay, so what is chemistry? I mean, chemistry is sort of
link |
02:39:05.760
a story of, you know, chemical reactions are like you've got this particular chemical that's
link |
02:39:10.960
represented as some graph of, you know, these are, these are this configuration of molecules
link |
02:39:15.600
with these bonds and so on. And a chemical reaction happens, you've got these sort of two
link |
02:39:20.480
graphs, they interact in some way, you've got another graph or multiple other graphs out. So
link |
02:39:24.800
that's kind of the, the sort of the, the abstract view of what's happening in chemistry. And so
link |
02:39:30.960
when you do a chemical synthesis, for example, you are given certain sort of these are possible
link |
02:39:36.240
reactions that can happen. And you're asked, can you piece together this a sequence of such reactions,
link |
02:39:41.920
a sequence of such sort of axiomatic reactions, usually called name reactions in chemistry,
link |
02:39:46.400
can you piece together a sequence of these reactions, so that you get out at the end,
link |
02:39:51.440
this great molecule you were trying to synthesize. And so that's a story very much like theorem
link |
02:39:55.440
proving. And people have done, actually, they started in the 1960s, looking at, at kind of the
link |
02:40:01.120
theorem proving approach to that, although it didn't really, it didn't, it didn't sort of done too early,
link |
02:40:06.080
I think. But anyway, so that's kind of the view is that that chemistry chemical reactions are
link |
02:40:10.880
this story of, of all these different sort of paths of possible things that go on. Okay, let's,
link |
02:40:16.560
let's go to an even lower level. Let's say, instead of asking about which species of molecules
link |
02:40:23.360
we're talking about, let's look at individual molecules. And let's say we're looking at individual
link |
02:40:27.440
molecules, and they are having chemical reactions. And we're building up this big graph of all these
link |
02:40:32.240
reactions that are happening. Okay, so, so then we've got this big graph. And by the way, that
link |
02:40:37.200
big graph is incredibly similar to these hypergraph rewriting things. In fact, in the underlying
link |
02:40:44.240
theory of multi computation, there, these things we call token event graphs, which are basically,
link |
02:40:49.280
you've broken your state into tokens, like in the case of a hypergraph, you've broken it into
link |
02:40:53.840
hyper edges. And each event is just consuming some number of tokens, and producing some number of
link |
02:40:59.440
tokens. But then you have to, there's a lot of work to be done on update rules.
link |
02:41:04.480
In terms of what they actually offer chemistry. Yeah, what they offer our observed chemistry.
link |
02:41:09.680
Yes, indeed. Yes, indeed. And we've been working on that actually, because we have this beautiful
link |
02:41:13.760
system in, in Wolfram language for representing chemistry symbolically. So we actually have,
link |
02:41:18.160
you know, this is a, this is an ongoing thing to actually figure out what they are for some
link |
02:41:21.600
practical cases. Does that require human injection or can it be automatically discovered, these
link |
02:41:27.520
update rules? Well, if we can do quantum chemistry better, we could probably discover them
link |
02:41:30.960
automatically. But I think in, in reality, right now, it's like, there are these particular
link |
02:41:35.600
reactions. And really, to understand what's going on, we're probably going to pick a particular
link |
02:41:39.840
subtype of chemistry. And just because, because let me explain where this is going, the place
link |
02:41:45.440
that here's, here's where this is going. So we've got this whole network of all these
link |
02:41:50.080
molecules, having all these reactions and so on. And this is some whole multi computational story,
link |
02:41:55.680
because each, each sort of chemical reaction event is its own separate event, we're saying
link |
02:42:02.560
they all happen asynchronously, we're not describing in what order they happen, you know,
link |
02:42:06.720
maybe that order is governed by some quantum mechanics thing, doesn't really matter,
link |
02:42:10.560
we're just saying they happen in some order. And then we ask, what is the, what's the, you know,
link |
02:42:16.000
how do we think about the system? Well, this thing is some kind of big multi computational
link |
02:42:20.960
system. The question is, what is the chemical observer? And one possible chemical observer is,
link |
02:42:26.240
all you care about is, did you make that particular drug molecule? You're just asking,
link |
02:42:30.160
you know, the, for the one path, another thing you might care about is, I want to know the
link |
02:42:34.240
concentration of each species, right? I want to know, you know, at every stage, I'm going to solve
link |
02:42:39.840
the differential equations that represent the concentrations. And I want to know what those
link |
02:42:43.280
all are. But there's more, because when, and it's kind of like, you're going below in statistical
link |
02:42:49.200
mechanics, there's kind of all these molecules bouncing around. And you might say, we're just
link |
02:42:55.280
going to ignore, we're just going to look at the aggregate densities of certain kinds of molecules,
link |
02:43:00.000
but you can look at a lower level, you can look at this whole graph of possible interactions.
link |
02:43:04.800
And so the kind of the idea would be, what, you know, is the only chemical observer,
link |
02:43:10.000
one who just cares about overall concentrations, or can there be a chemical observer who cares
link |
02:43:15.680
about this network of what happened? And so that the question then is, so let me give an analogy.
link |
02:43:22.080
So this is where I think this is potentially very relevant to molecular, molecular biology and
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02:43:26.160
molecular computing. When we think about a computation, usually we say, it's input, it's
link |
02:43:31.920
output, we, you know, or chemistry, we say, there's this input, we're going to make this molecule
link |
02:43:36.560
as the output. But what if what we actually encode, what if our computation, what if the
link |
02:43:42.880
thing we care about is some part of this dynamic network? What if it isn't just the input and
link |
02:43:48.000
the output that we care about? What if there's some dynamics of the network that we care about?
link |
02:43:51.760
Now, imagine you're a chemical observer, what is a chemical observer? Well, in molecular biology,
link |
02:43:57.760
there are all kinds of weird sorts of observers, there are membranes that exist that have, you
link |
02:44:03.200
know, different kinds of molecules that combine to them, things like this. It's not obvious that the,
link |
02:44:08.640
from a human scale, we just measure the concentration of something is the relevant story.
link |
02:44:13.760
We can imagine that, for example, when we look at this whole network of possible reactions,
link |
02:44:18.480
we can imagine, you know, at a physical level, we can imagine, well, what was the actual momentum
link |
02:44:22.560
direction of that, of that molecule? What was it, which we don't pay any attention to when we're
link |
02:44:26.880
just talking about chemical concentrations? What was the orientation of that molecule,
link |
02:44:31.040
these kinds of things? And so here's the place where I'm, I have a little suspicion, okay?
link |
02:44:36.640
So one of the questions in biology is what matters in biology? And that is, you know,
link |
02:44:41.200
we have all these chemical reactions, we have all these, all these molecular processes going on in,
link |
02:44:46.400
you know, in biological systems, what matters? And, you know, one of the things is to be able
link |
02:44:52.400
to tell what matters, well, so a big story of the what matters question was what happened in
link |
02:44:57.040
genetics in 1953 when DNA, when it was figured out how DNA worked. Because before that time,
link |
02:45:02.800
you know, genetics have been all these different effects and complicated things. And then it was
link |
02:45:06.720
realized, ah, there's something new, a molecule can store information, which wasn't obvious before
link |
02:45:12.240
that time, a single molecule can store information. So there's a place where there can be something
link |
02:45:17.040
important that's happening in molecular biology. And it's just in the sequence that's storing
link |
02:45:21.760
information in a molecule. So the possibility now is imagine this dynamic network, this, you know,
link |
02:45:28.720
causal graphs and multiway causal graphs and so on, that represent all of these different
link |
02:45:33.520
reactions between molecules. What if there is some aspect of that that is storing information
link |
02:45:38.800
that's relevant for molecular biology? In the dynamic aspect of that. Yes, that's right. So
link |
02:45:43.840
that it's similar to how the structure of a DNA molecule stores information, it could be the
link |
02:45:49.680
dynamics of the system, some stores information. And this kind of process might allow you to give
link |
02:45:56.240
predictions of what that would be. Well, yes, but also imagine that you're trying to do,
link |
02:46:02.000
for example, imagine you're trying to do molecular computation. Okay, you might think the way we're
link |
02:46:07.520
going to do molecular computation is, we're just going to run the thing, we're going to see what
link |
02:46:10.960
came out, we're going to see what molecule came out. This is saying that's not the only thing you
link |
02:46:15.280
can do. There is a different kind of chemical observer that you can imagine constructing,
link |
02:46:20.000
which is somehow sensitive to this dynamic network. Exactly how that works, how we make that
link |
02:46:25.120
measurement, I don't know, but a few ideas, but that that's what's important, so to speak. And
link |
02:46:31.520
that that means, and by the way, you can do the same thing, even for Turing machines, you can say
link |
02:46:35.760
if you have a multiway Turing machine, you can say, how do you compute with a multiway Turing
link |
02:46:40.800
machine? You can't say, well, we've got this input and this output, because the thing has all these
link |
02:46:45.600
threads of time, it's got lots of outputs. And so then you say, well, what does it even mean to be
link |
02:46:50.240
a universal multiway Turing machine? I don't fully know the answer to that. But it has an
link |
02:46:54.640
interesting idea, freak Turing out for sure. Because then the dynamics of the trajectory of
link |
02:47:01.280
the computation matters. Yes, yes. I mean, but the thing is that that so this is again a story of
link |
02:47:07.920
what's the observer, so to speak. And chemistry, what's what's the observer there? Now, to give
link |
02:47:12.080
an example of where that might matter, a very sort of present day example is in immunology,
link |
02:47:20.320
where, we have whatever it is, 10 billion different kinds of antibodies that are all
link |
02:47:26.160
these different shapes and so on, we have a trillion different kinds of T cell receptors
link |
02:47:30.960
that we can that we produce. And the traditional theory of immunology is this
link |
02:47:36.800
clonal selection theory, where we're constantly producing, randomly producing all these different
link |
02:47:41.440
antibodies. And as soon as one of those binds to an antigen, then that one gets amplified,
link |
02:47:46.160
and we produce more of that antibody and so on. Back in the 1960s, immunologist called Nils
link |
02:47:53.120
Yerner, who was the guy who invented molecular antibodies, various other things, kind of had
link |
02:47:58.240
this network theory of the immune system, where it would be like, well, we produce antibodies,
link |
02:48:02.320
but then we produce antibodies to the antibodies, anti antibodies, and we produce anti anti antibodies,
link |
02:48:07.760
and we get this whole dynamic network of interactions between different immune system
link |
02:48:12.000
cells. And that was that, that was kind of a qualitative theory at that time. And it's,
link |
02:48:18.880
I've been a little disappointed because I've been studying immunology a bit recently. And I knew
link |
02:48:23.040
something about this, like 35 years ago or something. And I knew, you know, I'd read a
link |
02:48:26.640
bunch of the books, and I talked to a bunch of the people and so on. And it was like an emerging
link |
02:48:31.360
theoretical immunology world. And then I look at the books now, and they're very thick, because
link |
02:48:36.720
they've got, you know, there's just a ton known about immunology, and, you know, all these different
link |
02:48:40.960
pathways, all these different details and so on. But the theoretical sections seem to have shrunk.
link |
02:48:47.280
And so it's, so the question is, what, you know, for example, immune memory, where is the,
link |
02:48:53.600
where does the immune memory reside? Is it actually some cell sitting in our bone marrow
link |
02:48:57.680
that is, you know, living for the whole of our lives that's going to spring into action as soon
link |
02:49:01.760
as we're showing the same antigen? Or is it something different from that? Is it something
link |
02:49:05.920
more dynamic? Is it something more like some network of interactions between these different
link |
02:49:10.320
kinds of immune system cells and so on? And it's known that there are plenty of interactions
link |
02:49:14.880
between T cells and, you know, there's plenty of dynamics. But what the consequence of that
link |
02:49:19.840
dynamics is is not clear. And to have a qualitative theory for that doesn't, doesn't seem to exist.
link |
02:49:26.320
In fact, I was just, just been trying to study this. So I'm quite incomplete in my study of
link |
02:49:30.320
these things. But I was a little bit taken aback because I've, I've been looking at these things.
link |
02:49:34.320
And it's like, and then they get to the end where they have the most advanced theory that they've
link |
02:49:37.680
got. And it turns out it's a cellular automaton theory. It's like, okay, well, at least I understand
link |
02:49:43.920
that theory. But, but, you know, I think that the possibility is that in, this is a place where,
link |
02:49:52.160
if you want to know, you know, explain roughly how the immune system works, it ends up being
link |
02:49:56.720
this dynamic network. And then the, the, you know, the immune consciousness, so to speak,
link |
02:50:02.240
the observer ends up being something that, you know, in the end, it's kind of like, does the human
link |
02:50:07.280
get sick or whatever. But it's a, it's something which is a complicated story that relates to this
link |
02:50:12.960
whole sort of dynamic network and so on. And I think that's another place where this kind of
link |
02:50:17.120
notion of, where, where I think multi computation has the possibility, see one of the things,
link |
02:50:22.640
okay, you can end up with something where, yes, there is a general relativity in there.
link |
02:50:26.560
There, but it turns out, but it may turn out that the observer who sees general relativity
link |
02:50:31.760
in the immune system is an observer that's irrelevant to what we care about, about the
link |
02:50:35.760
immune system. I mean, it could be, yes, there is some effect where, you know, there's some,
link |
02:50:40.240
you know, time dilation of T cells interacting with whatever, but it's like, that's an effect
link |
02:50:45.360
that's just irrelevant. And the thing we actually care about is things about, you know,
link |
02:50:49.760
what happens when you have a vaccine that goes into someplace in shapespace and, you know,
link |
02:50:54.320
how does that affect other places in shapespace and how does that spread? You know, what's the,
link |
02:50:58.640
what's the analog of the speed of light in shapespace, for example, that's an important issue.
link |
02:51:03.120
If you have one of these dynamic theories, it's like, you know, you're, you're poking to shapespace
link |
02:51:07.520
by having, you know, let's say, a vaccine or something that has a particular configuration
link |
02:51:11.920
in shapespace, how, how quickly as this dynamic network spreads out, how quickly do you get
link |
02:51:18.240
sort of other antibodies in different places in shapespace, things like that.
link |
02:51:22.160
When you say shapespace, you mean the shape of the molecules?
link |
02:51:24.400
Yes.
link |
02:51:25.040
And then, so this is like, it could be deeply connected to the protein and multi protein
link |
02:51:30.080
folding, all of that kind of stuff. So to be able to say something interesting about the
link |
02:51:34.640
dance of proteins, that then actually has an impact on helping develop drugs, for example,
link |
02:51:42.800
or has an impact on virology, immunology, helping.
link |
02:51:46.880
Well, I think that the big thing is, you know, when we think about molecular biology,
link |
02:51:52.320
the, you know, what, what is the qualitative way to think about it? You know, in other words,
link |
02:51:57.760
is it chemical reaction networks? Is it, you know, genetics, you know, DNA, big, you know,
link |
02:52:04.800
big news, it's kind of, there's a digital aspect to the whole thing.
link |
02:52:08.240
You know, what is the qualitative way to think about how things work in biology?
link |
02:52:12.880
You know, when we think about, I don't know, some phenomenon like aging or something,
link |
02:52:16.240
which is a big complicated phenomenon, which just seems to have all these different tentacles,
link |
02:52:20.240
is it really the case that, that can be thought about in some, you know, without DNA,
link |
02:52:25.120
when people were describing, you know, genetic phenomena that were, you know, dominant,
link |
02:52:29.520
recessive, this, that, and the other, it got very, very complicated. And then people realized,
link |
02:52:33.680
oh, it's just, you know, and what is a gene and so on and so on and so on.
link |
02:52:37.680
Then people realized it's just base pairs. And there's this digital representation. And so the
link |
02:52:41.680
question is, what is the overarching representation that we can now start to think about using a
link |
02:52:46.400
molecular biology? I don't know how this will work out. And this is again, one of these things
link |
02:52:50.560
where, and the place where that gets important is, you know, maybe molecular biology is doing
link |
02:52:56.480
molecular computing by using some dynamic process that is something where it is very happily saying,
link |
02:53:03.200
oh, I just got a result. It's in the dynamic structure of this network. Now I'm going to go
link |
02:53:06.960
and do some other thing based on that result, for example. But we're like, oh, I don't know what's
link |
02:53:11.680
going on. You know, it's just, we just measured them levels of these chemicals and we couldn't
link |
02:53:16.240
conclude anything. But it just we're looking at the wrong thing. And so that's kind of the potential
link |
02:53:22.880
there. And it's, I mean, these things are, I don't know, it's for me, it's like, I've not really,
link |
02:53:30.080
that was not a view. I mean, I've thought about molecular computing for ages and ages and ages.
link |
02:53:34.400
And I've always imagined that the big story is kind of the original promise of nanotechnology
link |
02:53:40.400
of like, can we make a molecular scale constructor that will just build the molecule in any shape?
link |
02:53:45.920
I don't think I'm now increasingly concluding, that's not the big point. The big point is something
link |
02:53:51.200
more dynamic. That will be an interesting endpoint for any of these things. But that's
link |
02:53:56.000
perhaps not the thing, you know, because the one example we have in molecular computing
link |
02:54:00.160
that's really working is us biological organisms. And, you know, maybe the thing that's important
link |
02:54:05.840
there is not this, you know, what chemicals do you make, so to speak, but more this kind of dynamic
link |
02:54:11.360
process dynamic process. And then you can have a good model like the hypo grafted to then
link |
02:54:15.520
explore what like simulated again, make predictions and if they
link |
02:54:21.040
I think just have a way to reason about biology. I mean, it's hard, you know, but first of all,
link |
02:54:26.560
biology doesn't have theories like physics, you know, physics is a much more successful sort of
link |
02:54:31.680
global theory kind of kind of area, you know, biology, what are the global theories of biology,
link |
02:54:37.200
pretty much Darwinian evolution, that's the only global theory of biology, you know, any other
link |
02:54:42.080
theory is just a, well, the kidneys work this way, this thing works this way and so on. There
link |
02:54:46.800
isn't, I suppose, another global theory is digital information in DNA. That's another sort of global
link |
02:54:52.080
fact about biology. But the difficult thing to do is to match something you have a model of in
link |
02:54:59.600
the hypo graft to the actual, like, how do you discover the theory? How do you discover the
link |
02:55:04.560
theory? Okay, you have something that looks nice and makes sense, but like, you have to match it
link |
02:55:08.960
to validation and experiment. Oh, sure, right. And that's tricky because you're walking around in
link |
02:55:13.920
the dark. Not entirely. I mean, so, you know, for example, and what we've been trying to think about
link |
02:55:19.920
is take actual chemical reactions. Okay. So, you know, one of my goals is, can I compute the primes
link |
02:55:26.960
with molecules? Okay, that's if I can do that, then I kind of maybe I can compute things. And,
link |
02:55:32.880
you know, there's this nice automated lab, these guys, these emerald cloud lab people have built
link |
02:55:37.360
with Wolfen language and so on. That's an actual physical lab. And you send it a piece of Wolfen
link |
02:55:41.920
language code and it goes and, you know, actually does physical experiments. And so one of my
link |
02:55:47.280
goals, because I'm not a test tube kind of guy, I'm more of a software kind of person, is can I
link |
02:55:52.640
make something where, you know, in this automated lab, we can actually get it so that there's some
link |
02:55:57.520
gel that we made. And, you know, the positions of the stripes are the primes. I love it. Yeah.
link |
02:56:02.720
I mean, that would be that will be an example of where and that will be with a particular,
link |
02:56:08.320
you know, framework for actually doing the molecular computing, you know, with particular
link |
02:56:12.880
kinds of molecules. And there's a lot of kind of ambient technological mess, so to speak, associated
link |
02:56:18.480
with Oh, is it carbon? Is it this? Is it that, you know, is it important that there's a bromine
link |
02:56:22.800
atom here, etc. etc. etc. This is all chemistry that I don't know much about. And, you know,
link |
02:56:28.320
that's that's a sort of, you know, unfortunately, that's down at the level, you know, I would like
link |
02:56:33.200
to be at the software level, not at the level of the transistors, so to speak. But in chemistry,
link |
02:56:38.320
you know, there's a certain amount we have to do, I think at the level of transistors before we get
link |
02:56:42.240
up to being able to do it, although, you know, automated labs certainly help in in setting that
link |
02:56:47.360
up. I talked to a guy named Charles Hoskinson. He mentioned that he's collaborating with you.
link |
02:56:55.040
He's an interesting guy. He sends me papers on speaking of automated theorem proving a lot.
link |
02:57:00.560
He's exceptionally well read on that area as well. So what's the nature of your collaboration
link |
02:57:05.520
with him? He's the creator of Cardano. What's the nature of the collaboration between Cardano
link |
02:57:11.360
and the whole space of blockchain and Wolfram, Wolfram Alpha, Wolfram Blockchain, all that kind
link |
02:57:15.760
of stuff. Well, okay, we're segueing to a slightly different world. But but so, although not completely
link |
02:57:23.680
I'm not completely unconnected. Right. The whole thing is somehow connected. I know. I mean,
link |
02:57:29.360
you know, the strange thing in my life is I've sort of alternated between doing basic science
link |
02:57:33.440
and doing technology about five times in my life so far. And the thing that's just crazy about it
link |
02:57:39.040
is, you know, every time I do one of these alternations, I think there's not going to be a
link |
02:57:43.680
way back to the other thing. And like I thought for this physics project, I thought, you know,
link |
02:57:47.920
we're doing fundamental theory of physics, maybe it'll have an application in 200 years.
link |
02:57:52.160
But now I've realized, actually, this multi computation idea is applicable here and now.
link |
02:57:58.800
And in fact, it's also giving us this way. I'll just mention one other thing. And then
link |
02:58:03.840
we're going to talk about blockchain. The question of actually that relates to several
link |
02:58:11.120
different things. But one of the things about, okay, so our Wolfram language, which is our attempt
link |
02:58:19.360
to kind of represent everything in the world computationally. And it's the thing I kind of
link |
02:58:23.440
started building 40 years ago, in the form of actual Wolfram language, 35 years ago. It's kind
link |
02:58:29.760
of this idea of can we can we express things about the world in computational terms. And,
link |
02:58:37.280
you know, we've come a long way in being able to do that. Wolfram Alpha is kind of the consumer
link |
02:58:41.600
version of that where you're just using natural languages as input. And it turns it into our
link |
02:58:46.320
symbolic language. And that's, you know, the symbolic language, Wolfram language is what
link |
02:58:50.800
people use and have been using for the last 33 years. Actually, Mathematica, which is its
link |
02:58:55.840
first instantiation, will be one third of a century old in October. And that it's kind of
link |
02:59:05.360
interesting. What do you mean one third of a century? Does it mean 33 or 30? What do we
link |
02:59:09.200
mean? 33 and a third. 33 and a third. So I've never heard of anyone celebrating that anniversary,
link |
02:59:16.960
but I like it. I know. A third of a century, though, it's like, you know, get many, many
link |
02:59:21.120
slices of a century that are interesting. But, you know, I think that the thing that's really
link |
02:59:25.600
striking about that is that means, you know, including the whole sort of technology stack
link |
02:59:29.840
I built around that's about 40 years old. And that means it's a significant fraction of the total
link |
02:59:34.160
age of the computer industry. And it's, I mean, I think it's cool that we can still run, you know,
link |
02:59:39.360
Mathematica version one programs today and so on. And we've sort of maintained compatibility.
link |
02:59:44.960
And we've been just building this big tower all those years of just more and more and more
link |
02:59:49.760
computational capabilities. It's sort of interesting, we just made this this picture
link |
02:59:54.160
of kind of the different kind of threads of computational content of, you know, mathematical
link |
02:59:59.920
content and, and, you know, all sorts of things with, you know, data and graphs and whatever
link |
03:00:05.840
else. And what you see in this picture is about the first 10 years, it's kind of like it's just
link |
03:00:10.560
a few threads. And then then about maybe 15, 20 years ago, it kind of explodes in this whole
link |
03:00:16.640
collection of different threads of all these different capabilities that are now part of
link |
03:00:20.720
orphan language and representing different things in the world. But the thing that was
link |
03:00:25.200
super lucky in some sense is it's all based on one idea. It's all based on the idea of symbolic
link |
03:00:30.880
expressions and transformation rules for symbolic expressions, which was kind of what I originally
link |
03:00:36.240
put into this SMP system back in 1979, that was a predecessor of the whole orphan language stack.
link |
03:00:42.880
So that idea was an idea that I got from sort of trying to understand mathematical logic and so
link |
03:00:48.720
on. It was my attempt to kind of make a general human comprehensible model of computation of
link |
03:00:55.040
the just everything is a symbolic expression. And all you do is transform symbolic expressions.
link |
03:01:00.000
And, you know, in, in retrospect, I was very lucky that I understood as little as I understood
link |
03:01:06.320
then, because had I understood more, I would have been completely freaked out about all the
link |
03:01:11.200
different ways that that kind of model can fail. Because what do you do when you have a symbolic
link |
03:01:17.680
expression, you make transformations for symbolic expressions? Well, for example, one question is
link |
03:01:22.320
there may be many transformations that could be made in a very multi computational kind of way.
link |
03:01:26.880
But what we're doing is picking, we're using the first transformation that applies. And we keep
link |
03:01:32.240
doing that until we reach a fixed point. And that's the result. And that's kind of a very,
link |
03:01:37.360
it's kind of a way of sort of sliding around the edge of multi computation. And back when I was
link |
03:01:42.880
working on SMP and things, I actually thought about these questions about about how, you know,
link |
03:01:48.240
how, what determines the this kind of evaluation path. So for example, you know, you work out
link |
03:01:53.280
Fibonacci, you know, Fibonacci is recursive thing, f of n is f of n minus one plus f of n minus two,
link |
03:01:58.960
and you get this whole tree of recursion, right. And there's the question of how do you evaluate
link |
03:02:03.440
that tree of recursion? Do you do it sort of depth first, where you go all the way down one side,
link |
03:02:07.920
you do it breadth first, where you're kind of collecting the terms together, where you know
link |
03:02:12.560
that you know, f of eight plus f of seven, f of seven plus f of six, you can collect the f of
link |
03:02:16.720
sevens and so on. These are, you know, I didn't realize that at the time, it's kind of funny,
link |
03:02:21.280
I was working on on gauge field theories back in 1979. And I was also working on the evaluation
link |
03:02:27.040
model in SMP, and they're the same problem. But it took me 40 more years to realize that.
link |
03:02:33.360
And this question about how you do this sort of evaluation front, that's a question of reference
link |
03:02:38.320
frames. It's a question of kind of the the story of, I mean, that that's, that is basically this
link |
03:02:44.800
question of, in what order is the universe evaluated? And that and so what you realize is
link |
03:02:50.480
there's this whole sort of world of different kinds of computation that you can do sort of
link |
03:02:54.800
multi computationally. And that's a, that's an interesting thing. It has a lot of implications
link |
03:02:59.040
for distributed computing and so on. It also has a potential implication for blockchain,
link |
03:03:03.440
which we haven't fully worked out, which is, and this is not what we're doing with Cardano, but
link |
03:03:08.080
this is a different thing. The, this is something where one of the questions is, when you have,
link |
03:03:17.120
in a sense, blockchain is a deeply sequentialized story of time, because in blockchain, there's
link |
03:03:22.640
just one copy of the ledger, and you're saying, this is what happened, you know, time has progressed
link |
03:03:28.720
in this way. And there are little things around the edges, as you try and reach consensus and so
link |
03:03:32.800
on. And, and, you know, actually, we just recently, we've had this little conference, we organized
link |
03:03:38.400
about the theory of distributed consensus, because I realized that a bunch of interesting things
link |
03:03:42.800
that some of our science can tell one about that. But that's a different, let's, let's not go down
link |
03:03:46.960
that, that part. Yeah, yeah. But distributed consensus that still has a sequential, there's
link |
03:03:50.880
like one. There's still sequentiality. So don't tell me you're thinking through like how to apply
link |
03:03:56.160
multi computation to blockchain. Yes. And so, so that becomes a story of, you know, instead of
link |
03:04:03.680
transactions all having to settle in one ledger, it's like a story of all these different ledgers,
link |
03:04:09.440
and they all have to have some ultimate consistency, which is what causal invariance would give one,
link |
03:04:14.320
but it can take a while. And the, it can take a while is kind of like quantum mechanics.
link |
03:04:19.040
So it's kind of what's happening is that these different paths of history that correspond to,
link |
03:04:24.080
you know, in one path of history, you got paid this amount in another path of history,
link |
03:04:28.000
you got paid this amount. In the end, the universe will always become consistent. Now,
link |
03:04:32.880
now the way it will, it works is, okay, it's a little bit more complicated than that. What happens
link |
03:04:38.160
is the way space is knitted together in our theory of physics is through all these events.
link |
03:04:43.600
And the, the, the idea is that the way that economic space is knitted together is,
link |
03:04:49.600
is there these autonomous events that essentially knit together economic space? So there are all
link |
03:04:55.280
these threads of transactions that are happening. And the question is, can they be made consistent?
link |
03:04:59.440
Are there, is there something forcing them to be sort of a consistent fabric of economic reality?
link |
03:05:05.440
And sort of what this has led me to is trying to realize how does economics fundamentally work?
link |
03:05:11.360
And, you know, what is economics? And, you know, what, what are the atoms of economics,
link |
03:05:16.800
so to speak? And so what I've kind of realized is that, that sort of the, perhaps I don't even
link |
03:05:22.960
know if this is right yet. There's sort of events in economics of transactions. There are states of
link |
03:05:28.400
agents that are kind of the atoms of economics. And then transactions are kind of agents,
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03:05:34.720
transact and some, transact in some way, and that's an event. And then the question is,
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03:05:39.840
how do you knit together sort of economic space from that? What is there an economic space? Well,
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03:05:45.200
all these transactions, there's a whole complicated collection of possible transactions. But one
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03:05:49.120
thing that's true about economics is we tend to have the notion of a definite value for things.
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03:05:54.640
We could imagine that, you know, you buy a cookie from somebody and they want to get a movie ticket.
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03:06:05.280
And there is some way that AI bots could make some path from the cookie to the movie ticket
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03:06:12.240
by all these different trans intermediate transactions. But in fact, we have an approximation
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03:06:17.920
to that, which is we say they each have a dollar value. And we have this kind of numeraire concept
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03:06:24.080
of there's just a way of kind of, of taking this whole complicated space of transactions
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03:06:29.840
and parsing it in something which is a kind of a simplified thing that is kind of like a parsing
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03:06:35.920
of physical space. And so my guess is that the yet again, I mean, it's crazy that all these things
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03:06:42.880
are so connected. This is another multi computation story, another story of where what's happening
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03:06:48.800
is that the economic consciousness, the economic observer is not going to deal with all of those
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03:06:54.800
are different microscopic transactions. They're just going to parse the whole thing by saying,
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03:06:58.880
there's this value, it's a number. And that's that's their understanding of their summary
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03:07:03.760
of this economic network. And there will be all kinds of things like they're all kinds of
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03:07:07.680
arbitrage opportunities, which are kind of like the quantum effects in this whole thing. And
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03:07:12.880
that's, you know, and places where there's where there's sort of different paths that can be followed
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03:07:17.440
and and so on. And there's so the question is, can one make a sort of global theory of economics?
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03:07:24.720
And then my test case is again, what is time dilation in economics? And and I know for,
link |
03:07:30.880
you know, if you imagine a very agricultural economics where people are growing lettuces and
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03:07:35.120
fields and things like this, and you ask questions about, well, if you're transporting
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03:07:39.040
lettuces to different places, you know, what is the value of the lettuces after you have to
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03:07:43.760
transport them versus if you're just sitting in one place and selling them, and you can kind of
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03:07:48.000
get a little bit of an analogy there. But I think there's a there's a better and more complete
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03:07:51.600
analogy. And that that's the question of is there a theory like general relativity, that is a global
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03:07:56.480
theory of economics? And is it about something we care about? It could be that there is a global
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03:08:01.120
theory, but it's about a feature of economic reality that isn't important to us. Now another
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03:08:06.240
part of the story is, can one use those ideas to make essentially a distributed blockchain,
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03:08:12.080
a distributed generalization of blockchain, kind of the quantum analog of money, so to speak,
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03:08:16.960
where where you have, for example, you can have uncertainty relations where you're saying, you
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03:08:22.080
know, well, if I if I insist on knowing my bank account right now, there'll be some uncertainty.
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03:08:27.600
If I'm prepared to wait a while, then it'll be much more certain. And so there's, you know,
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03:08:32.960
is there a way of using and so we've made a bunch of prototypes of this, which I'm not yet happy
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03:08:39.040
with, but I realized is to really understand these prototypes, I actually have to have a
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03:08:43.280
foundational theory of economics. And so that's kind of a, you know, it may be that we could
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03:08:48.080
deploy one of these prototypes as a practical system, but I think it's really going to be much
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03:08:52.240
better if we actually have an understanding of how this plugs into kind of economics.
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03:08:56.240
That means like a fundamental theory of transactions between entities. Well, that's what
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03:09:02.400
you mean by economics. Yes, I think so. But I mean, you know, how how there emerge sort of
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03:09:07.680
laws of economics, I don't even know. And I've been asking friends of mine who are who are
link |
03:09:11.360
economists and things, what is economics? You know, is it an axiomatic theory? Is it a theory
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03:09:17.120
that is a kind of a qualitative description theory? Is it, you know, what kind of a theory is it? Is
link |
03:09:22.560
it a theory? You know, what kind of thinking it's like, like in biology, in evolutionary biology,
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03:09:27.520
for example, there's a certain, there's a certain pattern of thinking that goes on in evolutionary
link |
03:09:31.280
biology, where if you're a, you know, a good evolutionary biologist, somebody says, that creature
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03:09:36.480
has a weird horn. And they'll say, well, that's because this and this and this and the selection
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03:09:41.120
of this kind and that kind. And that's the story. And it's not a mathematical story. It's a story
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03:09:46.800
of a different type of thinking about these things. By the way, evolutionary biology is yet
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03:09:51.760
another place where it looks like this multi computational idea can be applied. And that's
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03:09:56.880
where, where maybe speciation is related to things like event horizons. And there's a whole,
link |
03:10:02.240
whole other kind of world of that. But it seems like this kind of model can be applicable to so
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03:10:07.360
many aspects, like the different levels of understanding of our reality. So it can be the
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03:10:15.360
biology, the chemistry, at the physics level, the economics, and you could potentially say, the
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03:10:21.440
thing is, it's like, okay, sure, at all these levels in my rhyme, it might make sense as a
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03:10:27.440
model. The question is, can you make useful predictions at one of these levels?
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03:10:31.440
And that's, that's right. And that's, that's really a question of, you know, it's a weird
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03:10:36.000
situation because it's a situation where the model probably has definite consequences.
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03:10:41.600
The question is, are they consequences we care about? Yeah. And that's some, you know, and so,
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03:10:47.280
so in the case of, in the economic case, the, where, so, you know, the one, one thing is this,
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03:10:56.640
this idea of using kind of physics like notions to construct a kind of distributed analog block
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03:11:02.720
chain. Okay, the much more pragmatic thing is a different direction. And it has to do with
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03:11:08.080
this computational language that we built to describe the world that knows about, you know,
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03:11:12.800
different kinds of cookies and knows about different cities and knows about how to compute
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03:11:17.360
all these kinds of things. One of the things that is of interest is if you want to run the world,
link |
03:11:23.120
you need, you know, with, with, with contracts and laws and rules and so on. There are rules
link |
03:11:28.160
at a human level. And there are kind of things like, and so this, this gets one into the idea of
link |
03:11:34.000
computational contracts. You know, right now, when we write a contract, it's a piece of legalese,
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03:11:39.600
it's, you know, it's just written in English. And it's not something that's automatically
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03:11:43.760
analyzable, executable, whatever else, it's just English, you know, back in Gottfried Leibniz,
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03:11:50.080
back in, you know, 1680 or whatever, was like, I'm going to, you know, figure out how to use
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03:11:56.560
logic to decide legal cases and so on. And he had kind of this idea of, let's make a computational
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03:12:02.320
language for the human, for human law. Forget about modeling nature, forgot about natural laws.
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03:12:08.880
What about human law? Can we make kind of a computational representation of that?
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03:12:13.040
Well, I think finally we're close to being able to do that. And one of the projects that I hope
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03:12:17.680
to get to, as soon as the, there's a little bit of slowing down of some of this Cambrian explosion
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03:12:23.120
that's happening as a project I've been meaning to really do for a long time, which is what I'm
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03:12:27.280
calling a symbolic discourse language. It's just finishing the job of being able to represent
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03:12:32.480
everything like the conversation we're having in computational terms. And one of the use cases
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03:12:38.320
for that is computational contracts. Another use case is something like the Constitution that says
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03:12:43.600
what the AIs, what we want the AIs to do. But this is useful. So you're saying,
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03:12:48.240
so these are like, you're saying computational contracts, but the smart contracts, this is what's
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03:12:53.120
in the domain of cryptocurrencies known as smart contracts. And so the language you've developed,
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03:12:57.920
this symbolic or seek to further develop symbolic discourse language, enables you to
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03:13:05.520
write a contract. Write a contract that richly represents
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03:13:10.640
some aspect of the world. But so, I mean, smart contracts tend to be right now,
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03:13:15.440
mostly about things happening on the blockchain. And sometimes they have oracles. And in fact,
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03:13:20.000
our WolfMalpha API is the main thing people use to get information about the real world,
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03:13:25.280
so to speak, within smart contracts. So WolfMalpha, as it stands, is a really good oracle
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03:13:30.880
for whoever wants to use it. That's perhaps where the relationship with Cardano is.
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03:13:34.640
Yeah. Well, that's how we started getting involved with blockchains, as we realized people were
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03:13:38.080
using, you know, WolfMalpha as the oracle for smart contracts, so to speak. And so that got us
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03:13:43.600
interested in blockchains in general. And what was ended up happening is, WolfMalpha language is
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03:13:49.360
with its symbolic representation of things is really very good at representing
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03:13:53.360
things like blockchains. And so I think we now have, I mean, don't really know all the comparisons,
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03:13:58.240
but we now have a really nice environment within WolfMalpha language for dealing with the sort of,
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03:14:03.760
you know, for representing what happens in blockchains, for analyzing what happens in
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03:14:07.280
blockchains. We have a whole effort in blockchain analytics. And, you know, we've sort of published
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03:14:14.240
some samples of how that works. But it's, you know, because our technology stack, WolfMalpha language
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03:14:19.440
and Mathematica are very widely used in the quant finance world, there's a sort of immediate
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03:14:25.920
sort of co evolution there of sort of the quant finance kind of thing, and blockchain analytics.
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03:14:32.720
And that's some, so it's kind of the representation of blockchain in computational language.
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03:14:37.520
Then ultimately, it's kind of like, how do you run the world with code? That is, how do you write
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03:14:43.280
sort of all these things which are right now regulations and laws and contracts and things
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03:14:47.680
in computational language. And kind of the ultimate vision is that sort of something happens in the
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03:14:53.440
world. And then there's this giant domino effect of all these computational contracts that trigger
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03:14:57.920
based on the thing that happened. And there's a whole story to that. And of course, you know,
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03:15:03.200
I like to always pay attention to the latest things that are going on. And I really, I kind of like
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03:15:08.320
blockchain because it's a, it's a, it's another rethinking of kind of computation. It's kind of
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03:15:13.600
like, you know, cloud computing was a little bit of that of sort of persistent kind of
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03:15:18.960
computational resources and so on. And, you know, this multi computation is a big rethinking of
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03:15:24.400
kind of what it means to compute. Blockchain is another bit of rethinking of what it means to
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03:15:29.040
compute the idea that you lodge kind of these autonomous lumps of computation out there in
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03:15:33.920
the blockchain world. And one of the things that just sort of for fun, so to speak, as we've been
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03:15:40.320
doing a bit of stuff with NFTs, and we just did some NFTs on Cardano, and we'll be doing some more.
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03:15:45.600
And, you know, we did some cellular automaton NFTs on Cardano, like quite a bit. And, you know,
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03:15:52.400
one of the things I've realized about NFTs is that there's kind of this notion, and we're
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03:15:58.000
really working on this, you know, I like recording stuff, you know, one of the things that's come
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03:16:03.280
out of kind of my science, I suppose, is this history matters type story of, you know, it's
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03:16:09.520
not just the current stage, it's the history that matters. And I've kind of, I don't think this is,
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03:16:14.000
I should be realizing, maybe it's not coincidental that I'm sort of the human who's recorded more
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03:16:18.720
about themselves than anybody else. And then I end up with these science results that say history
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03:16:23.280
matters, which was not those things, I didn't think those were connected. But there are at least
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03:16:28.400
correlated, yes. Yeah, right. So, you know, this question about sort of recording what has happened
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03:16:34.000
and having sort of a permanent record of things, one of the things that's kind of interesting
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03:16:38.320
there is, you know, you put up a website and it's got a bunch of stuff on it. But, you know,
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03:16:42.160
you have to keep paying the hosting fees or the thing's going to go away. But one of the things
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03:16:46.480
about blockchain is quite interesting is if you put something on a blockchain and you pay,
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03:16:51.040
you know, your commission to get that thing, you know, put on, you know, mind put on the blockchain,
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03:16:56.800
then in a sense, everybody who comes after you is, you know, they are motivated to keep your
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03:17:02.720
thing alive, because that's what keeps the consistency of the blockchain. So in a sense,
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03:17:06.960
with sort of the NFT world, it's kind of like, if you want to have something permanent, well,
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03:17:11.760
at least for the life of the blockchain, but even if the blockchain goes out of circulation,
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03:17:16.400
so to speak, there's going to be enough value in that whole collection of transactions
link |
03:17:20.640
that people are going to archive the thing. But that means that, you know, pay once,
link |
03:17:24.240
and you're kind of, you're lodged in the blockchain forever. And so we've been kind of playing around
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03:17:29.520
with the sort of a hobby thing of mine of thinking about sort of the NFTs and how you,
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03:17:37.040
and sort of the consumer idea of kind of the, it's the anti, you know, it's the opposite of the
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03:17:42.640
Snapchat view of the world. There's a permanence to it that's heavily incentivized. And thereby,
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03:17:49.840
you can have a permanence of history. Right. And that's kind of the, now, you know, so that's one
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03:17:57.040
of the things we've been doing with Cardano. And it's kind of fun. I think that, I mean,
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03:18:01.280
this whole question about, you know, you mentioned automated theorem proving and blockchains and
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03:18:05.360
so on. And as I've thought about this kind of physics inspired distributed blockchain,
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03:18:09.760
obviously, they're the sort of the proof that it works, that there are no double spends,
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03:18:15.280
there's no whatever else. That proof becomes a very formal kind of almost a matter of physics,
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03:18:21.200
so to speak. And, you know, it's been, it's been an interesting thing for the,
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03:18:25.440
for the practical blockchains to do kind of actual automated theorem proving. And I don't
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03:18:30.240
think anybody's really managed it in an interesting case yet. It's a thing that people,
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03:18:34.560
you know, aspire to, but I think it's a challenging thing. Because basically the point is one of the,
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03:18:39.440
one of the things about proving correctness of something is, well, you know, people say,
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03:18:44.000
I've got this program, and I'm going to prove it's correct. And it's like, what does that mean?
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03:18:47.760
You have to say what correct means. I mean, it's, it's kind of like, then you have to have
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03:18:51.440
another language. And people are very confused back in past decades of, you know, oh, we're
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03:18:56.000
going to prove the correctness by representing the program in another language, which we also
link |
03:19:00.720
don't know whether it's correct. And, you know, often by correctness, we just mean it can't crash
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03:19:05.440
or it can't scribble on memory. But, but the thing is that there's this complicated tradeoff.
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03:19:10.640
Because as soon as there's, as soon as you're really using computation, you have computational
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03:19:15.200
irreducibility, you have undecidability, if you want to use computation seriously, you have to
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03:19:21.040
kind of let go of the idea that you're going to be able to box it in and say, we're going to have
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03:19:26.880
just this happen and not anything else. I mean, this is a, this is an old fact. I mean, Goedl's
link |
03:19:31.360
theorem tries to say, you know, piano arithmetic, the axioms of arithmetic, can you box in the integers
link |
03:19:37.680
and say these axioms give just the integers and nothing but the integers? Goedl's theorem showed
link |
03:19:42.000
that wasn't the case. There's a, you know, you can have all these wild, weird things that are
link |
03:19:46.720
obey the piano axioms, but aren't integers. And there's this kind of infinite hierarchy
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03:19:51.360
of additional axioms you would have to add. And it's kind of the same thing. You don't get to,
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03:19:56.080
you know, if you want to say, I want to know what happens, you're boxing yourself in, and there's
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03:20:00.560
a limit to what can happen, so to speak. So it's a, it's a complicated tradeoff. And it's a,
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03:20:04.480
it's a, it's a big tradeoff for AI, so to speak. It's kind of like, do you want to let computation
link |
03:20:09.200
actually do what it can do? Or do you want to say, no, it's very, very boxed in to the point
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03:20:13.920
where we can understand every step. And that's a, that's kind of a thing that, that, that becomes
link |
03:20:19.120
difficult to do. But that's some, I mean, in general, I would say one of the things that's
link |
03:20:24.640
kind of complicated in my sort of life and the whole sort of story of computational language
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03:20:30.080
and all this technology and science and so on. I mean, I kind of, in the flow of one's life,
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03:20:35.840
it's sort of interesting to see how these things play out. Because I, you know, I've kind of concluded
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03:20:41.040
that I'm in the business of making kind of artifacts from the future, which means, you know,
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03:20:46.320
there are things that I've done, I don't know, this physics project, I don't know whether anybody
link |
03:20:49.680
would have gotten to it for 50 years. You know, the fact that mathematics is a third of a century
link |
03:20:54.560
old. And I know that a bunch of the core ideas are not well absorbed. I mean, that is, people
link |
03:21:00.480
finally got this idea that I thought was a triviality of notebooks, that was 25 years.
link |
03:21:05.360
And, you know, some of these core ideas about symbolic computation and so on,
link |
03:21:09.680
are not, are not absorbed. I mean, people, people use them every day in Wolfram language,
link |
03:21:15.200
and you know, do all kinds of cool things with them. But if you say, what is the fundamental
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03:21:19.040
intellectual point here, it's, it's not well absorbed. And it's, it's something where you
link |
03:21:23.680
kind of realize that you're, you're sort of building things. And I kind of made this, this
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03:21:28.160
thing about, you know, we're building artifacts from the future, so to speak. And I mentioned that
link |
03:21:31.680
it's our, we have a conference every, it's coming up actually in a couple of weeks, our annual
link |
03:21:36.720
technology conference, where we talk about all the, all the things we're doing. And, you know,
link |
03:21:42.480
so I was talking about it last year, about, you know, we're making artifacts from the future.
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03:21:46.560
And I was kind of like, I had some, some version of that that was kind of a dark and frustrated
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03:21:51.600
thing of like, you know, I'm building things which nobody's going to care about until long
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03:21:55.280
after I'm dead, so to speak. But, but, but then I realized, you know, people were sort of telling
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03:22:01.680
me afterwards, you know, that's exactly how, you know, we're using Wolfram language in some
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03:22:06.640
particular setting in, you know, some computational X field or some organization or whatever. And
link |
03:22:11.440
it's like people are saying, Oh, you know, what did you manage to do? You know, well, we know
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03:22:16.000
that in principle, it will be possible to do that, but we didn't know that was possible now.
link |
03:22:19.520
And it's kind of like that's the, that's sort of the business we're in. And in a sense,
link |
03:22:23.200
with some of these ideas in science, you know, I feel a little bit the same way that there are
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03:22:27.760
some of these things where, you know, some, some things like, for example, this whole idea, well,
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03:22:33.520
so, so to, to relate to another sort of piece of history and the future, one of, you know,
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03:22:38.240
I mentioned, we mentioned at the beginning kind of complexity as this thing that I was interested
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03:22:42.720
in back 40 years ago and so on, where does complexity come from? Well, I think we kind of
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03:22:47.760
nailed that. The answer is in the computational universe, even simple programs make it. And
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03:22:53.120
that's kind of the secret the nature has that allows you to make it. So, so that's kind of the
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03:22:58.720
that that's that part. But the bigger picture there was this idea of this kind of computational
link |
03:23:03.200
paradigm, the idea that you could go beyond mathematical equations, which have been sort of
link |
03:23:07.760
the primary modeling medium for 300 years. And so it was like, look, it is inexorably the case
link |
03:23:14.560
that people will use programs, rather than just equations. And, you know, I was saying that in
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03:23:19.040
the 1980s. And people were, you know, I published my big book, New Kind of Science, that'll be 20
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03:23:24.000
years ago, next year. So in 2002, and people are saying, Oh, no, this can't possibly be true. You
link |
03:23:30.240
know, we know, for 300 years, we've been doing all this stuff, right? To be fair, I now realize
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03:23:35.840
on a little bit more analysis of what people actually said, in pretty much every field other
link |
03:23:40.640
than physics, people said, Oh, these are new models, that's pretty interesting. In physics,
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03:23:46.640
people were like, we've got our physics models, we're very happy with them.
link |
03:23:49.680
Yeah, in physics, there's more resistance because of the attachment and the power of the equations,
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03:23:54.800
right? The idea that programs might be the right way to approach, right, this field was,
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03:24:00.480
there's some resistance and like you're saying, it takes time for somebody who likes the idea of
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03:24:05.920
time dilation and all these applications, I thought you would understand this.
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03:24:09.520
Yeah, right. But you know, and computational irreducibility,
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03:24:12.560
yes, exactly. But I mean, it is really interesting that just 20 years, a span of 20 years,
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03:24:18.800
it's gone from, you know, pitchforks and horror to, yeah, we get it. And, you know, it's helped
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03:24:26.400
that we've, you know, in our current effort in fundamental physics, we've gotten a lot further,
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03:24:31.840
and we've managed to put a lot of puzzle pieces together, that makes sense. But the thing that
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03:24:37.040
I've been thinking about recently is this field of complexity. So I've kind of was a sort of a
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03:24:42.480
field builder back in the 1980s, I was kind of like, okay, you know, can we, you know, I'd
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understood this point that there was this sort of fundamental phenomenon of complexity, it showed up
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in lots of places. And I was like, this is an interesting sort of field of science. And I was
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recently was reminded I was at this, the very first sort of get together of what became the
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Santa Fe Institute. And I was like, in fact, there's even an audio recording of me sort of
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saying, people have been talking about, oh, what should this, you know, outfit do? And I was saying,
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well, there is this thing that I've been thinking about, it's this kind of idea of complexity.
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Nice. And it's kind of like, and that's, that's what that ended up.
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And you planted the seed of complexity to Santa Fe. That's beautiful. It's a beautiful vision.
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But I mean, so that, but what's happened then, is this idea of complexity and, you know,
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can, you know, and I started the first research center at University of Illinois for doing that
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in the first journal, complex systems and so on. And, and it's kind of an interesting thing in my
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life, at least that it's kind of like, you plant the seed, you have this idea, it's a kind of a
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science idea, you have this idea of sort of focusing on the phenomenon of complexity. The
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deeper idea was this computational paradigm. But the nominal idea is this kind of idea of
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complexity. Okay, then you roll time forward 30 years or whatever, 35 years, whatever it is.
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And you say, what happened? Okay, well, now there are 1000 complexity institutes around the world.
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I think, more or less, we've been trying to count them. And, you know, there are 40 complexity
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journals, I think. And so it's kind of like, what actually happened in this field? Right.
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And I look at a lot of what happened. And I'm like, you know, I have to admit,
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there's some eye rolling, so to speak. Because it's kind of like, like, what is what's what's
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actually going on? Well, what people definitely got was this idea of computational models.
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And then they got but they thought one of the one of the kind of cognitive mistakes, I think,
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is they say, we've got a computational model. And it's, and we're looking at a system that's
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complex. And our computational model gives complexity by golly, that must mean it's right.
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And unfortunately, because complexity is a generic phenomenon and computational irreducibility
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is a generic phenomenon that actually tells you nothing. And so then the question is, well,
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what can you do? You know, there's a lot of things that have been sort of done under this banner
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of complexity. And I think it's been very successful in providing sort of an interdisciplinary
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way of connecting different fields together, which is powerful in itself. Right. I mean,
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that's a very useful economics. And yeah, it is. It's a good organizing principle. But in the end,
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a lot of that is around the sort of computational paradigm, computational modeling. That's the
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raw material that powers that kind of that kind of correspondence, I think. But the question is
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sort of what is the, you know, I was just thinking recently, you know, we've been, I mean, the other
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we've been, we've been for years, people have told me, you should start some Wolfram Institute
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that does basic science. You know, all I have is a company that that builds software and we,
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you know, we have a little piece that does basic science as kind of a hobby. People are saying,
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you should start this Wolfram Institute thing. And, and I've been, you know, because I've known
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about lots of institutes, and I've seen kind of that flow of money and, and kind of, you know,
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what happens in different situations and so on. So I've been kind of reluctant, but, but I've,
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I've, I have realized that, you know, what we've done with our company over the last 35 years,
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you know, we built a very good machine for doing R&D and, you know, innovating and creating things.
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And I just applied that machine to the physics project. That's how we did the physics project
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in a fairly short amount of time with a, you know, efficient machine with, you know, various people
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involved and so on. And so, you know, it works for basic science. And it's like, we can do more of
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this. And so now... In biology and chemistry, so it's become an institute. Yes. Well, it needs to
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become an institute. An official institute. Right. But the thing that, so I was thinking about,
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okay, so what do we do with complexity? You know, what, what, there are all these people who've,
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you know, what, what should happen to that field? And what I realized is, there's kind of this area
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of foundations of complexity that's about these questions about simple programs, what they do,
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that's far away from a bunch of the detailed applications that people... Oh, it's not far away.
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It's the, it's the under, you know, the bedrock underneath those applications. And so I realized
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recently, this is my recent kind of little innovation of a sort, a post that I'll do very soon,
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the, about kind of, you know, the foundations of complexity, what really are they? I think
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they're really two ideas, two conceptual ideas that I hadn't really enunciated, I think, before.
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One is what I call metamodeling. The other is rulliology. So what is metamodeling? So metamodeling
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is, you've got this complicated model, and it's a model of, you know, hedgehogs interacting with
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this, interacting with that. And the question is, what's really underneath that? What is it?
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You know, is it a Turing machine? Is it a cellular automaton? You know,
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what is the underlying stuff underneath that model? And so there's this kind of meta science
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question of, given these models, what is the core model? And I realized, I mean, to me,
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that's sort of an obvious question. But then I realized, I've been doing language design for 40
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years. And language design is exactly that question, you know, underneath all of this
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detailed stuff people do, what are the underlying primitives? And that's a question people haven't
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tended to ask about models. They say, well, we've got this nice model for this and that and the
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other. What's really underneath it? And what, you know, because once you have the thing that's
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underneath it, well, for example, this multi computation idea is an ultimate metamodeling
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idea, because it's saying underneath all these fields is one kind of paradigmatic structure.
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And, you know, you can, you can imagine the same kind of thing, much more sort of,
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much sort of shallower levels in different kinds of modeling. So the first activity is this kind
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of metamodeling, the kind of the models about models, so to speak, you know, what is the,
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what's, you know, drilling down into models? That's one thing. The other thing is this,
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this thing that I think we're going to call Ruleology, which is kind of the, okay, you've got
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these simple rules, you've got cellular automata, you've got Turing machines, you've got substitution
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systems, you've got register machines, you've got all these different things. What do they actually
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do in the wild? And this is an area that I've spent a lot of time, you know, working on and
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it's a lot of stuff in my new kind of science book is about this, you know, this new book I wrote
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about combinators is, is full of stuff like this. And, and this journal complex systems has lots of
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papers about these kinds of things. But, but there isn't really a home for people who do
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Ruleology or what I'm not. As you call the basic science of rules. Yes. Yes. Right. So it's, it's
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like, you've got some, what is it? Is it mathematics? No, it isn't really like mathematics. In fact,
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from my now understanding of mathematics, I understand that it's the molecular dynamics level.
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It's not the level that mathematicians have traditionally cared about. It's not computer
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science, because computer science is about writing programs that do things, you know,
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that were for a purpose, not programs in the wild, so to speak. It's not physics, it doesn't have
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anything to do with, you know, it may be underneath some physics, but it's not physics as such.
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So it just hasn't had a home. And if you look at, you know, but what's great about it is,
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it's a surviving field, so to speak. It's, it's something where, you know, one of the things I,
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I find sort of inspiring about mathematics, for example, is you look at mathematics that was done,
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you know, in ancient Greece, ancient, you know, Babylon, Egypt and so on, it's still here today.
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You know, you find an icosahedron that somebody made in ancient Egypt, you look at it, oh,
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that's a very modern thing. It's an icosahedron, you know, it's a timeless kind of, kind of activity.
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And this idea of studying simple rules and what they do, it's a timeless activity. And I can see
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that over the last 40 years or so, as, you know, even with cellular automata, it's kind of like,
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you know, you can sort of catalog what, what are the different cellular automata used for.
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And, you know, like the simplest rules, like, like one, you might even know this one, rule 184.
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It's rule 184 is a minimal model for road traffic flow. And, you know, it's also a
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minimal model for various other things. But it's kind of fun that you can literally say,
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you know, rule 90 is a minimal model for this and this and this. Rule four is a minimal model for
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this. And it's kind of remarkable that you can just buy in this raw level of this kind of study
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of rules. They then branch, they're the raw material that you can use to make models of
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different things. So it's a, it's a very pure basic science. But it's one that, you know,
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people have explored it, but they've been kind of a little bit in the wilderness. And I think,
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you know, one of the things that I would like to do finally is, is, you know, I always thought that
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sort of this notion of pure and chaos, pure and chaos being the acronym for my book, New Kind of
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Science, was, was something that people should be doing. And, you know, we tried to figure out
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what's the right institutional structure to do this stuff. You know, we, we dealt with a bunch
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of universities. Oh, you know, can we do this here? Well, what department would be in it? Well,
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it isn't in a department. It's, it's its own new kind of thing. That's why, that's why the book was
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called the New Kind of Science. It's kind of the, the, because that's an increasingly good description
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of what it is, so to speak. We're actually, we were thinking about kind of the rheological society,
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because we're realizing that it's kind of, it's, it's some, you know, there's a, there's a, it's
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very, it's very interesting. I mean, I've never really done something like this before, because
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there's this whole group of researchers who are, who've been doing things that are really,
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in some cases, very elegant, very surviving, very solid, you know, here's this thing that
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happens in this very abstract system. But it's like, it's like, what is that part of, you know, it's,
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it doesn't have a home. And I think that's something I, you know, I kind of fault myself for not
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having been more, you know, when complexity was developing in the 80s, I didn't understand the,
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the, the danger of applications. That is, it's really cool that you can apply this to economics,
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and you can apply it to evolutionary biology, and this and that and the other. But what happens
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with applications is everything gets sucked into the applications. And the pure stuff,
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it's like the pure mathematics, there isn't any pure mathematics, so to speak. It's all just
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applications of mathematics. And I, I failed to kind of make sure that this kind of pure area was,
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was kind of maintained and, and, and developed. And I think now, you know, one of the things I,
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I want to try to do, and, and, you know, it's a funny thing because I'm used to, look, I've been a,
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a tech CEO for more than half my life now. So, you know, this is what I know how to do. And, you
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know, I can, I can make stuff happen, and get projects to happen, even as it turns out, basic
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science projects, in that kind of setting, and how that translates into kind of, you know,
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there are a lot of people working on, for example, our physics project sort of distributed through
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the academic world, and that's working just great. But the question is, you know, can we have a sort
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of accelerator mechanism that makes use of kind of what we've learned in, in sort of R&D innovation?
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And, you know, but on the other hand, it's a funny thing because, you know, in a company,
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in the end, the thing is, you know, it's a company, it makes products that sell things,
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sells things to people. In, you know, when you're doing basic research, one of the challenges is
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there isn't that same kind of, of sort of mechanism. And so it's, it's, it's, you know, how do you
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drive the thing in a, in a kind of, in a lead kind of way, so that it really can, can make
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forward progress rather than, you know, what can often happen in, you know, in academic settings
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where it's like, well, there are all these flowers blooming, but it's not clear that there, you know,
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that it's, you have to have a central mission and a drive, just like you do with the company
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that's delivering a big overarching product. And that's, that's, but the challenges, you know,
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when you have a, the, the, the economics of the world are such that, you know, when you're delivering
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a product and people say, wow, that's useful, we'll buy it. And then that kind of feeds back
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in, okay, then you can, then you can pay the people who build it to eat, you know, so they can eat
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and so on. And with basic science, the payoff is very much less visible. And, and, you know,
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with the physics project, as I say, the big surprise has been that, I mean, you know,
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for example, well, the big surprise with the physics project is that it's looks like it has
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near term applications. And I was like, I'm guessing this is 200 years away. It's, I was kind of using
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the analogy of, of, you know, Newton, starting a satellite launch company, which would have been
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kind of wrong time. And, you know, but, but it turns out that's not the case. But, but we can't
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guarantee that. And if you say, we're signing up to do basic research, basic rheology, let's say.
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03:37:28.480
And, you know, and we can't, we don't know the horizon, you know, it's an unknown horizon. It's
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kind of like an undecidable kind of proposition of when is this proof going to end, so to speak?
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When is it going to be something that, that they get supplied? Well, I hope this is, this becomes a
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vibrant new field of rheology. I love it. Like I told you many, many times, it's one of the most
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amazing ideas that has been brought to this world. So I hope you get a bunch of people to explore
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this world. Thank you once again for spending a really valuable time with me today. Fun stuff. Thank
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03:38:06.960
you. Thanks for listening to this conversation with Stephen Wolfram. To support this podcast,
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03:38:12.480
please check out our sponsors in the description. And now let me leave you with some words from
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Richard Feynman. Nature uses only the longest threads to weave her patterns. So each small piece
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of her fabric reveals the organization of the entire tapestry. Thank you for listening and hope
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to see you next time.