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Grant Sanderson: 3Blue1Brown and the Beauty of Mathematics | Lex Fridman Podcast #64


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The following is a conversation with Grant Sanderson.
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He's a math educator and creator of Three Blue One Brown,
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a popular YouTube channel
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that uses programmatically animated visualizations
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to explain concepts in linear algebra, calculus,
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and other fields of mathematics.
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This is the Artificial Intelligence Podcast.
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If you enjoy it, subscribe on YouTube,
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And now here's my conversation with Grant Sanderson.
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If there's intelligent life out there in the universe,
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do you think their mathematics is different than ours?
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Jumping right in.
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I think it's probably very different.
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There's an obvious sense.
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The notation is different, right?
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I think notation can guide what the math itself is.
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I think it has everything to do
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with the form of their existence, right?
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Do you think they have basic arithmetic?
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So interrupt.
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Yeah, so I think they count, right?
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I think notions like one, two, three,
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the natural numbers, that's extremely, well, natural.
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That's almost why we put that name to it.
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As soon as you can count,
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you have a notion of repetition, right?
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Cause you can count by two, two times or three times.
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And so you have this notion of repeating
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the idea of counting, which brings you addition
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and multiplication.
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I think the way that we extend to the real numbers,
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there's a little bit of choice in that.
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So there's this funny number system
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called the surreal numbers,
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that it captures the idea of continuity.
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It's a distinct mathematical object.
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You could very well, you know,
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model the universe and motion of planets
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with that as the backend of your math, right?
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And you still have kind of the same interface
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with the front end of what physical laws you're trying to,
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or what physical phenomena you're trying to describe
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with math.
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And I wonder if the little glimpses that we have
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of what choices you can make along the way
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based on what different mathematicians
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have brought to the table
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is just scratching the surface,
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surface of what the different possibilities are
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if you have a completely different mode of thought, right?
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Or a mode of interacting with the universe.
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And you think notation is the key part of the journey
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that we've taken through math?
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I think that's the most salient part
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that you'd notice at first.
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I think the mode of thought is gonna influence things
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more than like the notation itself.
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But notation actually carries a lot of weight
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when it comes to how we think about things
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more so than we usually give a credit for.
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I would be comfortable saying.
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Do you have a favorite or least favorite piece of notation
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in terms of its effectiveness?
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Yeah, yeah, well, so least favorite,
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one that I've been thinking a lot about
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that will be a video I don't know when,
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but we'll see the number E.
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We write the function E to the X,
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this general exponential function
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with a notation E to the X that implies
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you should think about a particular number,
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this constant of nature,
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and you repeatedly multiply it by itself.
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And then you say, oh, what's E to the square root of two?
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And you're like, oh, well, we've extended the idea
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of repeated multiplication.
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That's all nice.
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That's all nice and well.
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But very famously, you have like E to the pi I,
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and you're like, well, we're extending the idea
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of repeated multiplication into the complex numbers.
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Yeah, you can think about it that way.
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In reality, I think that it's just the wrong way
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of notationally representing this function,
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the exponential function,
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which itself could be represented a number
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of different ways.
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You can think about it in terms of the problem it solves,
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a certain very simple differential equation,
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which often yields way more insight
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than trying to twist to the idea of repeated multiplication,
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like take its arm and put it behind its back
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and throw it on the desk
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and be like, you will apply to complex numbers, right?
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That's not, I don't think that's pedagogically helpful.
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So the repeated multiplication
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is actually missing the main point,
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the power of E to the X.
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I mean, what it addresses is things where the rate
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at which something changes depends on its own value,
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but more specifically, it depends on it linearly.
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So for example, if you have like a population
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that's growing and the rate at which it grows
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depends on how many members of the population
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are already there.
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It looks like this nice exponential curve.
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It makes sense to talk about repeated multiplication,
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because you say, how much is there after one year,
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two years, three years, you're multiplying by something.
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The relationship can be a little bit different sometimes
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where let's say you've got a ball on a string,
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like a game of tether ball going around a rope, right?
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And you say, its velocity is always perpendicular
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to its position.
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That's another way of describing its rate of change
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is being related to where it is,
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but it's a different operation.
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You're not scaling it.
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It's a rotation.
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It's this 90 degree rotation.
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That's what the whole idea of like complex
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explanation is trying to capture,
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but it's obfuscated in the notation.
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When what it's actually saying,
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like if you really parse something like E to the Pi I,
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what it's saying is choose an origin,
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always move perpendicular to the vector
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from that origin to you, okay?
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Then when you walk Pi times that radius,
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you'll be halfway around.
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Like that's what it's saying.
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It's kind of the you turn 90 degrees
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and you walk, you'll be going in a circle.
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That's the phenomenon that it's describing,
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but trying to twist the idea of repeatedly multiplying
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a constant into that.
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Like I can't even think of the number of human hours,
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of like intelligent human hours that have been wasted
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trying to parse that to their own liking and desire
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among like scientists or electrical engineers
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or students have we were,
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which if the notation were a little different
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or the way that this whole function was introduced
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from the get go were framed differently,
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I think could have been avoided, right?
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And you're talking about
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the most beautiful equation in mathematics,
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but it's still pretty mysterious, isn't it?
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Like you're making it seem like it's a notational.
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It's not mysterious.
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I think the notation makes it mysterious.
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I don't think it's,
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I think the fact that it represents, it's pretty.
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It's not like the most beautiful thing in the world,
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but it's quite pretty.
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The idea that if you take the linear operation,
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of a 90 degree rotation,
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and then you do this general exponentiation thing to it,
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that what you get are all the other kinds of rotation,
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which is basically to say,
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if your velocity vector is perpendicular
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to your position vector, you walk in a circle,
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that's pretty.
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It's not the most beautiful thing in the world,
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but it's quite pretty.
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The beauty of it, I think comes from,
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perhaps the awkwardness of the notation,
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somehow still nevertheless coming together nicely.
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Cause you have like several disciplines coming together
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in a single equation.
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Well, I think.
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In a sense, like historically speaking.
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That's true.
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So like the number E is significant.
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Like it shows up in probability all the time.
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It like shows up in calculus all the time.
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It is significant.
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You're seeing it sort of mated with pi,
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this geometric constant and I,
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like the imaginary number and such.
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I think what's really happening there
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is the way that E shows up is when you have things
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like exponential growth and decay, right?
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It's when this relation that something's rate of change
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has to itself is a simple scaling, right?
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A similar law also describes circular motion.
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Because we have bad notation,
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we use the residue of how it shows up
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in the context of self reinforcing growth
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like a population growing or compound interest.
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The constant associated with that
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is awkwardly placed into the context
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of how rotation comes about
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because they both come from pretty similar equations.
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And so what we see is the E and the pi juxtaposed
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a little bit closer than they would be
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with a purely natural representation, I would think.
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Here's how I would describe the relation between the two.
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You've got a very important function we might call exp.
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That's like the exponential function.
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When you plug in one,
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you get this nice constant called E
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that shows up in like probability and calculus.
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If you try to move in the imaginary direction,
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it's periodic and the period is tau.
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So those are these two constants
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associated with the same central function,
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but for kind of unrelated reasons, right?
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And not unrelated, but like orthogonal reasons.
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One of them is what happens
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when you're moving in the real direction.
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One's what happens when you move in the imaginary direction.
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And like, yeah, those are related.
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They're not as related as the famous equation
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seems to think it is.
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It's sort of putting all of the children in one bed
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and they'd kind of like to sleep in separate beds
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if they had the choice, but you see them all there.
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And there is a family resemblance,
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but it's not that close.
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So actually thinking of it as a function is the better idea.
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And that's a notational idea.
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And yeah, like here's the thing.
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The constant E sort of stands as this numerical representative
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of calculus, right?
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Yeah.
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Calculus is the like study of change.
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So at the very least,
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there's a little cognitive dissonance using a constant
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to represent the science of change.
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I never thought of it that way.
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Yeah.
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Right?
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Yeah.
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But it makes sense why the notation came about that way.
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Yes.
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Because this is the first way that we saw it
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in the context of things like population growth
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or compound interest.
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It is nicer to think about as repeated multiplication.
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That's definitely nicer.
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But it's more that that's the first application
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of what turned out to be a much more general function
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that maybe the intelligent life,
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your initial question asked about
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would have come to recognize
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as being much more significant than the single use case,
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which lends itself to repeated multiplication notation.
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But let me jump back for a second to aliens
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and the nature of our universe.
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Okay.
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Do you think math is discovered or invented?
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So we're talking about the different kind of mathematics
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that could be developed by the alien species.
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The implied question is yeah,
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is math discovered or invented?
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Is fundamentally everybody going to discover
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the same principles of mathematics?
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So the way I think about it,
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and everyone thinks about it differently,
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but here's my take.
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I think there's a cycle at play
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where you discover things about the universe
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that tell you what math will be useful.
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And that math itself is invented in a sense.
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But of all the possible maths that you could have invented,
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it's discoveries about the world
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that tell you which ones are.
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So like a good example here is the Pythagorean theorem.
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When you look at this,
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do you think of that as a definition
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or do you think of that as a discovery?
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From the historical perspective, right, as a discovery?
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Because they were,
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but that's probably because they were using physical object
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to build their intuition.
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And from that intuition came the mathematics.
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So the mathematics wasn't in some abstract world
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detached from physics,
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but I think more and more math has become detached from,
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you know, when you even look at modern physics
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from string theory to even general relativity.
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I mean, all math behind the 20th and 21st century physics
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kind of takes a brisk walk outside
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of what our mind can actually even comprehend
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in multiple dimensions, for example,
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anything beyond three dimensions, maybe four dimensions.
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No, no, no.
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Higher dimensions can be highly, highly applicable.
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I think this is a common misinterpretation
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that if you're asking questions
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about like a five dimensional manifold,
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that the only way that that's connected
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to the physical world
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is if the physical world is itself
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a five dimensional manifold or includes them.
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Well, wait, wait, wait a minute, wait a minute.
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You're telling me you can imagine
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a five dimensional manifold?
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No, no, that's not what I said.
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I would make the claim that it is useful
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to a three dimensional physical universe
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despite itself not being three dimensional.
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So it's useful meaning to even understand
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a three dimensional world,
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it'd be useful to have five dimensional manifolds.
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Yes, absolutely.
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Because of state spaces.
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But you're saying in some deep way for us humans,
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it does always come back to that three dimensional world
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for the usefulness of the dimensional world.
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And therefore it starts with a discovery,
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but then we invent the mathematics
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that helps us make sense of the discovery in a sense.
link |
00:13:06.280
Yes, I mean, just to jump off
link |
00:13:07.880
of the Pythagorean theorem example,
link |
00:13:09.840
it feels like a discovery.
link |
00:13:11.200
You've got these beautiful geometric proofs
link |
00:13:12.920
where you've got squares and you're modifying their areas.
link |
00:13:14.640
It feels like a discovery.
link |
00:13:16.760
If you look at how we formalize the idea of 2D space
link |
00:13:19.640
as being R2, all pairs of real numbers,
link |
00:13:23.120
and how we define a metric on it and define distance,
link |
00:13:25.720
you're like, hang on a second,
link |
00:13:26.680
we've defined a distance
link |
00:13:28.080
so that the Pythagorean theorem is true
link |
00:13:30.120
so that suddenly it doesn't feel that great.
link |
00:13:32.480
But I think what's going on is the thing that informed us
link |
00:13:35.400
what metric to put on R2,
link |
00:13:38.000
to put on our abstract representation of 2D space
link |
00:13:41.400
came from physical observations.
link |
00:13:43.280
And the thing is there's other metrics
link |
00:13:44.640
you could have put on it.
link |
00:13:45.480
You could have consistent math
link |
00:13:47.200
with other notions of distance.
link |
00:13:49.160
It's just that those pieces of math
link |
00:13:50.880
wouldn't be applicable to the physical world that we study
link |
00:13:53.640
because they're not the ones
link |
00:13:54.600
where the Pythagorean theorem holds.
link |
00:13:56.200
So we have a discovery, a genuine bona fide discovery
link |
00:13:59.040
that informed the invention,
link |
00:14:00.480
the invention of an abstract representation of 2D space
link |
00:14:03.720
that we call R2 and things like that.
link |
00:14:06.240
And then from there,
link |
00:14:07.320
you just study R2 as an abstract thing
link |
00:14:09.720
that brings about more ideas and inventions and mysteries
link |
00:14:12.520
which themselves might yield discoveries.
link |
00:14:14.440
Those discoveries might give you insight
link |
00:14:17.040
as to what else would be useful to invent
link |
00:14:19.440
and it kind of feeds on itself that way.
link |
00:14:21.040
That's how I think about it.
link |
00:14:22.240
So it's not an either or.
link |
00:14:24.200
It's not that math is one of these or it's one of the others.
link |
00:14:26.840
At different times, it's playing a different role.
link |
00:14:29.240
So then let me ask the Richard Feynman question.
link |
00:14:33.160
Then along that thread is,
link |
00:14:36.440
what do you think is the difference between physics and math?
link |
00:14:40.360
There's a giant overlap.
link |
00:14:42.880
There's a kind of intuition that physicists have
link |
00:14:45.920
about the world that's perhaps outside of mathematics.
link |
00:14:49.000
It's this mysterious art that they seem to possess.
link |
00:14:52.680
We humans generally possess.
link |
00:14:54.240
And then there's the beautiful rigor of mathematics
link |
00:14:58.040
that allows you to, I mean, just like as we were saying,
link |
00:15:02.840
invent frameworks of understanding our physical world.
link |
00:15:08.360
So what do you think is the difference there
link |
00:15:10.640
and how big is it?
link |
00:15:11.840
Well, I think of math as being the study of abstractions
link |
00:15:14.760
over patterns and pure patterns in logic.
link |
00:15:17.360
And then physics is obviously grounded in a desire
link |
00:15:19.800
to understand the world that we live in.
link |
00:15:22.680
I think you're gonna get very different answers
link |
00:15:24.040
when you talk to different mathematicians
link |
00:15:25.560
because there's a wide diversity in types of mathematicians.
link |
00:15:28.120
There are some who are motivated very much by pure puzzles.
link |
00:15:31.480
They might be turned on by things like combinatorics.
link |
00:15:34.040
And they just love the idea of building up a set
link |
00:15:36.680
of problem solving tools applying to pure patterns.
link |
00:15:40.880
There are some who are very physically motivated
link |
00:15:43.320
who try to invent new math or discover math in veins
link |
00:15:48.680
that they know will have applications to physics
link |
00:15:50.960
or sometimes computer science.
link |
00:15:52.280
And that's what drives them, right?
link |
00:15:53.840
Like chaos theory is a good example of something
link |
00:15:55.560
that's pure math, that's purely mathematical.
link |
00:15:57.680
A lot of the statements being made,
link |
00:15:59.160
but it's heavily motivated by specific applications
link |
00:16:02.880
to largely physics.
link |
00:16:05.360
And then you have a type of mathematician
link |
00:16:06.680
who just loves abstraction.
link |
00:16:08.520
They just love pulling into the more and more abstract things
link |
00:16:10.720
the things that feel powerful.
link |
00:16:12.160
These are the ones that initially invented like topology
link |
00:16:15.240
and then later on get really into category theory
link |
00:16:17.520
and go on about like infinite categories and whatnot.
link |
00:16:20.400
These are the ones that love to have a system
link |
00:16:23.480
that can describe truths about as many things as possible.
link |
00:16:28.760
People from those three different veins
link |
00:16:30.800
of motivation into math are gonna give you
link |
00:16:32.160
very different answers about what the relation
link |
00:16:33.720
at play here is.
link |
00:16:34.760
Cause someone like Vladimir Arnold,
link |
00:16:37.680
who has written a lot of great books,
link |
00:16:40.560
many about like differential equations and such.
link |
00:16:42.520
He would say, math is a branch of physics.
link |
00:16:45.680
That's how he would think about it.
link |
00:16:47.160
And of course he was studying like differential equations
link |
00:16:49.160
related things because that is the motivator
link |
00:16:51.080
behind the study of PDEs and things like that.
link |
00:16:54.800
But you'll have others who like,
link |
00:16:56.680
especially the category theorists
link |
00:16:58.280
who aren't really thinking about physics necessarily.
link |
00:17:01.400
It's all about abstraction and the power of generality.
link |
00:17:04.560
And it's more of a happy coincidence
link |
00:17:06.440
that that ends up being useful
link |
00:17:08.360
for understanding the world we live in.
link |
00:17:10.920
And then you can get into like, why is that the case?
link |
00:17:12.880
It's sort of surprising that,
link |
00:17:15.080
that which is about pure puzzles and abstraction
link |
00:17:17.840
also happens to describe the very fundamentals
link |
00:17:21.080
of quarks and everything else.
link |
00:17:24.160
So what do you think the fundamentals of quarks
link |
00:17:28.840
and the nature of reality is so compressible
link |
00:17:33.240
into clean, beautiful equations
link |
00:17:35.320
that are for the most part simple, relatively speaking.
link |
00:17:39.280
A lot simpler than they could be.
link |
00:17:41.720
So you have, we mentioned to me like Stephen Wolfram
link |
00:17:45.360
who thinks that sort of,
link |
00:17:48.160
there's incredibly simple rules underlying our reality,
link |
00:17:51.880
but it can create arbitrary complexity.
link |
00:17:54.920
But there is simple equations.
link |
00:17:56.760
What, I'm asking a million questions
link |
00:17:59.200
that nobody knows the answer to.
link |
00:18:00.640
Yeah, I have no idea.
link |
00:18:02.040
Why is it simple?
link |
00:18:05.280
It could be the case that,
link |
00:18:07.080
there's like a filter iteration at play.
link |
00:18:08.480
The only things that physicists find interesting,
link |
00:18:10.600
other ones that are simple enough,
link |
00:18:11.680
they could describe it mathematically.
link |
00:18:13.280
But as soon as it's a sufficiently complex system,
link |
00:18:15.120
they're like, yeah, that's outside the realm of physics.
link |
00:18:16.920
That's biology or whatever have you.
link |
00:18:19.320
And of course, that's true, right?
link |
00:18:21.400
You know, maybe there's something where it's like,
link |
00:18:22.680
of course there will always be some thing that is simple
link |
00:18:26.520
when you wash away the like non important parts
link |
00:18:31.400
of whatever it is that you're studying.
link |
00:18:33.400
Just from like an information theory standpoint,
link |
00:18:35.160
there might be some like,
link |
00:18:36.640
you get to the lowest information component of it.
link |
00:18:39.440
But I don't know, maybe I'm just having
link |
00:18:40.880
a really hard time conceiving of what it would even mean
link |
00:18:43.000
for the fundamental laws to be like intrinsically complicated.
link |
00:18:48.360
Like some set of equations
link |
00:18:50.600
that you can't decouple from each other.
link |
00:18:52.520
Well, no, it could be that sort of we take for granted
link |
00:18:56.760
that the laws of physics, for example,
link |
00:18:59.960
are for the most part the same everywhere
link |
00:19:03.480
or something like that, right?
link |
00:19:05.320
As opposed to the sort of an alternative could be
link |
00:19:10.600
that the rules under which the world operates
link |
00:19:15.400
is different everywhere.
link |
00:19:17.240
It's like a deeply distributed system
link |
00:19:20.320
where just everything is just chaos.
link |
00:19:22.360
Like not in a strict definition of cast,
link |
00:19:25.520
but meaning like just it's impossible for equations
link |
00:19:30.360
to capture for to explicitly model the world
link |
00:19:34.000
as cleanly as the physical does.
link |
00:19:36.000
I mean, we almost take it for granted
link |
00:19:38.040
that we can describe,
link |
00:19:39.040
we can have an equation for gravity
link |
00:19:41.200
for action at a distance.
link |
00:19:42.760
We can have equations for some of these basic ways
link |
00:19:45.480
the plan is moving just the low level
link |
00:19:50.800
of the atomic scale, how the materials operate
link |
00:19:54.000
at the high scale, how black holes operate.
link |
00:19:56.960
But it seems like it could be,
link |
00:19:59.840
there's infinite other possibilities
link |
00:20:01.720
where none of it could be compressible into such equations.
link |
00:20:05.080
It just seems beautiful.
link |
00:20:06.560
It's also weird probably to the point you were making
link |
00:20:10.920
that it's very pleasant that this is true for our minds.
link |
00:20:15.120
So it might be that our minds are biased
link |
00:20:17.160
to just be looking at the parts of the universe
link |
00:20:19.680
that are compressible.
link |
00:20:21.760
And then we can publish papers on and have nice
link |
00:20:24.560
E equals empty squared equations.
link |
00:20:26.480
Right.
link |
00:20:27.320
Well, I wonder would such a world with uncompressible laws
link |
00:20:31.760
allow for the kind of beings that can think about
link |
00:20:35.160
the kind of questions that you're asking?
link |
00:20:37.800
That's true.
link |
00:20:38.640
Right.
link |
00:20:39.480
Like an anthropic principle coming into play
link |
00:20:40.640
at some weird way here.
link |
00:20:42.640
I don't know.
link |
00:20:43.480
Like I don't know what I'm talking about.
link |
00:20:44.800
Well, maybe the universe is actually not so compressible,
link |
00:20:48.040
but the way our brain evolved
link |
00:20:52.600
were only able to perceive the compressible parts.
link |
00:20:55.920
I mean, this is a sort of Chomsky argument.
link |
00:20:58.440
We are just descendants of apes
link |
00:20:59.920
over like really limited biological systems.
link |
00:21:03.640
So it totally makes sense
link |
00:21:04.720
that we're really limited little computers, calculators,
link |
00:21:08.640
that are able to perceive certain kinds of things
link |
00:21:10.280
and the actual world is much more complicated.
link |
00:21:13.000
Well, but we can do pretty awesome things, right?
link |
00:21:16.720
Like we can fly spaceships.
link |
00:21:18.360
And we have to have some connection of reality
link |
00:21:21.640
to be able to take our potentially oversimplified
link |
00:21:25.040
models of the world,
link |
00:21:26.320
but then actually twist the world to our will based on it.
link |
00:21:29.160
So we have certain reality checks
link |
00:21:30.480
that like physics isn't too far afield,
link |
00:21:33.520
simply based on what we can do.
link |
00:21:35.520
Yeah, the fact that we can fly is pretty good.
link |
00:21:37.360
It's great.
link |
00:21:38.200
Yeah.
link |
00:21:39.040
And land.
link |
00:21:39.880
It's a proof of concept that the laws
link |
00:21:41.880
we're working with are working well.
link |
00:21:44.960
So I mentioned to the internet that I'm talking to you.
link |
00:21:47.800
And so the internet gave some questions.
link |
00:21:50.240
So I apologize for these,
link |
00:21:51.640
but do you think we're living in a simulation
link |
00:21:54.560
that the universe is a computer
link |
00:21:56.960
or the universe is a computation running on a computer?
link |
00:22:01.280
It's conceivable.
link |
00:22:02.720
What I don't buy is, you know, you'll have the argument that,
link |
00:22:06.320
well, let's say that it was the case
link |
00:22:07.920
that you can have simulations,
link |
00:22:09.600
then the simulated world would itself
link |
00:22:12.600
eventually get to a point where it's running simulations.
link |
00:22:15.360
And then the second layer down
link |
00:22:17.240
would create a third layer down and on and on and on.
link |
00:22:19.440
So probabilistically,
link |
00:22:20.840
you just throw a dart at one of those layers.
link |
00:22:22.400
We're probably in one of the simulated layers.
link |
00:22:24.960
I think if there's some sort of limitations
link |
00:22:27.040
on like the information processing
link |
00:22:28.560
of whatever the physical world is,
link |
00:22:31.440
like it quickly becomes the case
link |
00:22:32.720
that you have a limit to the layers that could exist there
link |
00:22:35.600
because like the resources necessary
link |
00:22:38.080
to simulate a universe like ours clearly is a lot.
link |
00:22:41.680
Just in terms of the number of bits at play.
link |
00:22:43.680
And so then you can ask, well, what's more plausible?
link |
00:22:46.800
That there's an unbounded capacity
link |
00:22:49.120
of information processing
link |
00:22:50.360
in whatever the like highest up level universe is,
link |
00:22:53.640
or that there's some bound to that capacity,
link |
00:22:56.080
which then limits like the number of levels available.
link |
00:22:58.880
How do you play some kind of probability distribution
link |
00:23:00.800
on like what the information capacity is?
link |
00:23:02.560
I have no idea.
link |
00:23:03.720
But I don't, like people almost assume
link |
00:23:06.840
a certain uniform probability over all of those meta layers
link |
00:23:10.200
that could conceivably exist
link |
00:23:11.880
when it's a little bit like a Pascal's wager
link |
00:23:15.120
on like you're not giving a low enough prior
link |
00:23:16.960
to the mere existence of that infinite set of layers.
link |
00:23:20.840
Yeah, that's true.
link |
00:23:21.680
But it's also very difficult to contextualize
link |
00:23:24.480
the amount, so the amount of information processing power
link |
00:23:28.240
required to simulate like our universe
link |
00:23:31.360
seems like amazingly huge.
link |
00:23:35.120
But you can always raise two to the power of that.
link |
00:23:36.920
Yeah.
link |
00:23:37.760
Yeah, like numbers get big.
link |
00:23:40.480
And we're easily humbled by basically everything around us.
link |
00:23:43.720
So it's very difficult to kind of make sense of anything
link |
00:23:49.280
actually when you look up at the sky
link |
00:23:50.960
and look at the stars and the immensity of it all
link |
00:23:53.520
to make sense of us, the smallness of us,
link |
00:23:57.040
the unlikeliness of everything that's on this earth
link |
00:24:00.600
coming to be, then you could basically anything could be
link |
00:24:04.960
all laws of probability go out the window to me
link |
00:24:09.080
because I guess because the amount of information
link |
00:24:14.160
under which we're operating is very low.
link |
00:24:17.560
We basically know nothing about the world around us
link |
00:24:22.080
relatively speaking.
link |
00:24:23.400
And so when I think about the simulation hypothesis,
link |
00:24:26.600
I think it's just fun to think about it.
link |
00:24:29.200
But it's also, I think there is a thought experiment
link |
00:24:31.840
kind of interesting to think of the power of computation
link |
00:24:35.200
where there are the limits of a Turing machine,
link |
00:24:38.920
sort of the limits of our current computers
link |
00:24:41.000
when you start to think about artificial intelligence,
link |
00:24:44.040
how far can we get with computers?
link |
00:24:46.800
And that's kind of where the simulation hypothesis
link |
00:24:50.800
used to me as a thought experiment
link |
00:24:52.800
is the universe just a computer?
link |
00:24:56.640
Is it just a computation?
link |
00:24:58.560
Is all of this just a computation?
link |
00:25:00.440
And sort of the same kind of tools we apply
link |
00:25:02.360
to analyzing algorithms, can that be applied?
link |
00:25:05.080
If we scale further and further and further,
link |
00:25:07.320
will the arbitrary power of those systems
link |
00:25:09.600
start to create some interesting aspects
link |
00:25:12.000
that we see in our universe?
link |
00:25:13.880
Or is something fundamentally different
link |
00:25:15.960
needs to be created?
link |
00:25:17.480
Well, it's interesting that in our universe,
link |
00:25:20.360
it's not arbitrarily large, the power,
link |
00:25:22.680
that you can place limits on, for example,
link |
00:25:24.320
how many bits of information can be stored per unit area?
link |
00:25:27.320
Right, like all of the physical laws,
link |
00:25:29.920
we've got general relativity and quantum coming together
link |
00:25:32.280
to give you a certain limit on how many bits you can store
link |
00:25:36.200
within a given range before it collapses into a black hole.
link |
00:25:39.800
Like the idea that there even exists such a limit
link |
00:25:42.320
is at the very least thought provoking
link |
00:25:44.200
when, naively, you might assume,
link |
00:25:46.520
oh, well, technology could always get better and better,
link |
00:25:48.840
we could get cleverer and cleverer,
link |
00:25:50.480
and you could just cram as much information as you want
link |
00:25:53.720
into a small unit of space.
link |
00:25:55.800
That makes me think it's at least plausible
link |
00:26:01.800
that whatever the highest level of existence is
link |
00:26:05.800
doesn't admit too many simulations
link |
00:26:08.800
or ones that are at the scale of complexity
link |
00:26:10.800
that we're looking at.
link |
00:26:11.800
Obviously, it's just as conceivable that they do
link |
00:26:13.800
and that there are many, but I guess what I'm channeling
link |
00:26:18.800
is the surprise that I felt upon learning that fact,
link |
00:26:20.800
that information is physical in this way.
link |
00:26:23.800
There's a finiteness to it.
link |
00:26:25.800
Okay, let me just even go off on that
link |
00:26:27.800
from a mathematics perspective and a psychology perspective.
link |
00:26:31.800
How do you mix?
link |
00:26:33.800
Are you psychologically comfortable
link |
00:26:36.800
with the concept of infinity?
link |
00:26:38.800
I think so.
link |
00:26:39.800
Are you okay with it?
link |
00:26:40.800
I'm pretty okay, yeah.
link |
00:26:41.800
Are you okay?
link |
00:26:42.800
No, not really.
link |
00:26:43.800
It doesn't make any sense to me.
link |
00:26:45.800
I don't know.
link |
00:26:46.800
How many possible words do you think could exist
link |
00:26:51.800
that are just like strings of letters?
link |
00:26:54.800
That's a sort of mathematical statement as beautiful
link |
00:26:58.800
and we use infinity in basically everything we do
link |
00:27:02.800
in science, math and engineering, yes.
link |
00:27:05.800
But you said exist.
link |
00:27:08.800
The question is, you said letters or words?
link |
00:27:12.800
I said words.
link |
00:27:14.800
To bring words into existence to me,
link |
00:27:17.800
you have to start saying them or writing them
link |
00:27:20.800
or listing them.
link |
00:27:21.800
That's an instantiation.
link |
00:27:22.800
Okay.
link |
00:27:23.800
How many abstract words exist?
link |
00:27:25.800
Well, the idea of abstract.
link |
00:27:27.800
The idea of abstract notions and ideas.
link |
00:27:30.800
I think we should be clear on terminology.
link |
00:27:32.800
You think about intelligence a lot,
link |
00:27:34.800
like artificial intelligence.
link |
00:27:36.800
Would you not say that what it's doing
link |
00:27:38.800
is a kind of abstraction?
link |
00:27:40.800
Abstraction is key to conceptualizing the universe.
link |
00:27:44.800
You get this raw sensory data.
link |
00:27:46.800
I need something that every time you move your face
link |
00:27:48.800
a little bit, and they're not pixels,
link |
00:27:50.800
but analog of pixels on my retina change entirely,
link |
00:27:54.800
that I can still have some coherent notion
link |
00:27:56.800
of this is Lex, I'm talking about Lex.
link |
00:27:58.800
What that requires is you have a disparate set
link |
00:28:00.800
of possible images hitting me
link |
00:28:02.800
that are unified in a notion of Lex.
link |
00:28:05.800
That's a kind of abstraction.
link |
00:28:07.800
It's a thing that could apply to a lot of different images
link |
00:28:10.800
that I see and it represents it in a much more compressed way
link |
00:28:14.800
and one that's much more resilient to that.
link |
00:28:16.800
I think in the same way, if I'm talking about
link |
00:28:18.800
infinity as an abstraction,
link |
00:28:20.800
I don't mean nonphysical, woo woo, ineffable or something.
link |
00:28:25.800
What I mean is it's something that can apply
link |
00:28:27.800
to a multiplicity of situations
link |
00:28:29.800
that share a certain common attribute.
link |
00:28:31.800
In the same way that the images of your face on my retina
link |
00:28:33.800
share enough common attributes
link |
00:28:35.800
that I can put this single notion to it.
link |
00:28:37.800
In that way, infinity is an abstraction,
link |
00:28:39.800
and it's very powerful.
link |
00:28:41.800
It's only through such abstractions
link |
00:28:43.800
that we can actually understand
link |
00:28:45.800
the world and logic and things.
link |
00:28:47.800
In the case of infinity, the way I think about it,
link |
00:28:49.800
the key entity is the property
link |
00:28:51.800
of always being able to add one more.
link |
00:28:53.800
No matter how many words you can list,
link |
00:28:55.800
you just throw an A at the end of one
link |
00:28:57.800
and you have another conceivable word.
link |
00:28:59.800
You don't have to think of all the words at once.
link |
00:29:01.800
It's that property.
link |
00:29:03.800
I could always add one more
link |
00:29:05.800
that gives it this nature of infinitiveness
link |
00:29:07.800
in the same way that there are certain properties
link |
00:29:09.800
of your face that give it the lexness.
link |
00:29:13.800
So, like, infinity should be no more worrying
link |
00:29:16.800
than the I can always add one more sentiment.
link |
00:29:19.800
That's a really elegant,
link |
00:29:21.800
much more elegant way than I could put it.
link |
00:29:23.800
So thank you for doing that as yet another abstraction.
link |
00:29:26.800
And yes, indeed.
link |
00:29:28.800
That's what our brain does.
link |
00:29:30.800
That's what intelligence systems do.
link |
00:29:32.800
That's what programming does.
link |
00:29:34.800
That's what science does is build abstraction
link |
00:29:36.800
on top of each other.
link |
00:29:38.800
And yet, there is, at a certain point,
link |
00:29:40.800
quote, woo, right?
link |
00:29:43.800
Sort of.
link |
00:29:45.800
And because we're now, it's like,
link |
00:29:48.800
we built this stack of, you know,
link |
00:29:51.800
the only thing that's true is the stuff
link |
00:29:53.800
that's on the ground.
link |
00:29:54.800
Everything else is useful for interpreting this.
link |
00:29:56.800
And at a certain point,
link |
00:29:58.800
you might start floating into ideas
link |
00:30:01.800
that are surreal and difficult
link |
00:30:04.800
and take us into areas that are
link |
00:30:06.800
disconnected from reality
link |
00:30:08.800
in a way that we could never get back.
link |
00:30:10.800
What if instead of calling these abstract,
link |
00:30:12.800
how different would it be in your mind
link |
00:30:14.800
if we called them general?
link |
00:30:15.800
And the phenomena that you're describing
link |
00:30:17.800
is overgeneralization.
link |
00:30:18.800
When you try to...
link |
00:30:19.800
Generalization, yeah.
link |
00:30:20.800
Have a concept or an idea that's so general
link |
00:30:22.800
as to apply to nothing in particular
link |
00:30:24.800
in a useful way.
link |
00:30:25.800
Does that map to what you're thinking of
link |
00:30:27.800
when you think of...
link |
00:30:28.800
First of all, I'm playing a little
link |
00:30:29.800
just for the fun of it.
link |
00:30:30.800
Yeah, I know.
link |
00:30:31.800
Devil's Advocate.
link |
00:30:32.800
And I think our cognition,
link |
00:30:35.800
our mind is unable to visualize.
link |
00:30:38.800
So you do some incredible work
link |
00:30:40.800
with visualization and video.
link |
00:30:41.800
I think infinity is very difficult
link |
00:30:45.800
to visualize for our mind.
link |
00:30:47.800
We can delude ourselves
link |
00:30:49.800
into thinking we can visualize it.
link |
00:30:52.800
But we can't.
link |
00:30:53.800
I don't...
link |
00:30:54.800
I mean, I don't...
link |
00:30:55.800
I would venture to say it's very difficult.
link |
00:30:57.800
And so there's some concepts in mathematics
link |
00:30:59.800
like maybe multiple dimensions.
link |
00:31:01.800
We could sort of talk about it.
link |
00:31:03.800
It's impossible for us to truly intuit.
link |
00:31:07.800
And it just feels dangerous to me
link |
00:31:11.800
to use these as part of our toolbox of abstractions.
link |
00:31:16.800
On behalf of your listeners,
link |
00:31:17.800
I almost fear we're getting too philosophical.
link |
00:31:19.800
No.
link |
00:31:20.800
Heck no.
link |
00:31:21.800
Heck no.
link |
00:31:22.800
But I think to that point,
link |
00:31:24.800
for any particular idea like this,
link |
00:31:26.800
there's multiple angles of attack.
link |
00:31:28.800
I think when we do visualize infinity,
link |
00:31:31.800
what we're actually doing, you write dot, dot, dot.
link |
00:31:34.800
One, two, three, four, dot, dot, dot.
link |
00:31:36.800
Those are symbols on the page
link |
00:31:37.800
that are insinuating a certain infinity.
link |
00:31:42.800
What you're capturing with a little bit of design there
link |
00:31:45.800
is the I can always add one more property.
link |
00:31:49.800
I'm just as uncomfortable with you are
link |
00:31:52.800
if you try to concretize it so much
link |
00:31:55.800
that you have a bag of infinitely many things
link |
00:31:58.800
that I actually think of,
link |
00:31:59.800
no, not one, two, three, four, dot, dot, dot.
link |
00:32:01.800
One, two, three, four, five, six, seven, eight.
link |
00:32:03.800
I try to get them all in my head and you realize,
link |
00:32:05.800
oh, your brain would literally collapse
link |
00:32:07.800
into a black hole, all of that.
link |
00:32:09.800
And I honestly feel this with a lot of math
link |
00:32:11.800
that I try to read where I don't think of myself
link |
00:32:14.800
as like particularly good at math.
link |
00:32:18.800
In some ways, I get very confused
link |
00:32:20.800
often when I am going through some of these texts.
link |
00:32:23.800
And often what I'm feeling in my head is like,
link |
00:32:25.800
this is just so damn abstract.
link |
00:32:27.800
I just can't wrap my head around it.
link |
00:32:28.800
I just want to put something concrete to it
link |
00:32:31.800
that makes me understand.
link |
00:32:32.800
And I think a lot of the motivation for the channel
link |
00:32:34.800
is channeling that sentiment of,
link |
00:32:37.800
yeah, a lot of the things that you're trying to read out there,
link |
00:32:40.800
it's just so hard to connect to anything
link |
00:32:42.800
that you spend an hour banging your head
link |
00:32:44.800
against a couple of pages and you come out
link |
00:32:46.800
not really knowing anything more
link |
00:32:48.800
other than some definitions maybe
link |
00:32:51.800
and a certain sense of self defeat, right?
link |
00:32:54.800
One of the reasons I focus so much on visualizations
link |
00:32:57.800
is that I'm a big believer in,
link |
00:33:00.800
I'm sorry, I'm just really hampering on this idea of abstraction,
link |
00:33:03.800
being clear about your layers of abstraction, right?
link |
00:33:06.800
It's always tempting to start an explanation
link |
00:33:09.800
from the top to the bottom, okay?
link |
00:33:11.800
You give the definition of a new theorem.
link |
00:33:13.800
You're like, this is the definition of a vector space.
link |
00:33:15.800
For example, that's how we'll start a course.
link |
00:33:17.800
These are the properties of a vector space.
link |
00:33:19.800
First from these properties,
link |
00:33:21.800
we will derive what we need in order to do the math
link |
00:33:23.800
of linear algebra or whatever it might be.
link |
00:33:26.800
I don't think that's how understanding works at all.
link |
00:33:28.800
I think how understanding works is you start
link |
00:33:30.800
at the lowest level you can get at,
link |
00:33:32.800
where rather than thinking about a vector space,
link |
00:33:34.800
you might think of concrete vectors
link |
00:33:36.800
that are just lists of numbers
link |
00:33:38.800
or picturing it as like an arrow that you draw,
link |
00:33:41.800
which is itself like even less abstract than numbers
link |
00:33:44.800
because you're looking at quantities,
link |
00:33:46.800
like the distance of the X coordinate,
link |
00:33:48.800
the distance of the Y coordinate.
link |
00:33:50.800
It's as concrete as you could possibly get
link |
00:33:52.800
and it has to be if you're putting it in a visual, right?
link |
00:33:54.800
It's an actual arrow.
link |
00:33:56.800
It's an actual vector.
link |
00:33:58.800
You're not talking about like a quote unquote vector
link |
00:34:00.800
that could apply to any possible thing.
link |
00:34:02.800
You have to choose one if you're illustrating it.
link |
00:34:04.800
And I think this is the power of being
link |
00:34:06.800
in a medium like video,
link |
00:34:08.800
or if you're writing a textbook
link |
00:34:10.800
and you force yourself to put a lot of images,
link |
00:34:12.800
is with every image, you're making a choice
link |
00:34:14.800
with each choice, you're showing a concrete example.
link |
00:34:16.800
With each concrete example,
link |
00:34:18.800
you're aiding someone's path to understanding.
link |
00:34:20.800
I'm sorry to interrupt you,
link |
00:34:22.800
but you just made me realize
link |
00:34:24.800
that that's exactly right.
link |
00:34:26.800
So the visualizations you're creating
link |
00:34:28.800
while you're sometimes talking about abstractions,
link |
00:34:30.800
the actual visualization
link |
00:34:32.800
is an explicit low level example.
link |
00:34:34.800
Yes.
link |
00:34:36.800
So there's an actual, like in the code,
link |
00:34:38.800
you have to say what the vector is.
link |
00:34:40.800
What's the direction of the arrow?
link |
00:34:42.800
What's the magnitude?
link |
00:34:44.800
Yeah.
link |
00:34:46.800
So you're going,
link |
00:34:48.800
the visualization itself is actually going to the bottom
link |
00:34:50.800
of that.
link |
00:34:52.800
And I think that's very important.
link |
00:34:54.800
I also think about this a lot in writing scripts
link |
00:34:56.800
where even before you get to the visuals,
link |
00:34:58.800
the first instinct is to,
link |
00:35:00.800
I don't know why, I just always do,
link |
00:35:02.800
I say the abstract thing,
link |
00:35:04.800
I say the general definition, the powerful thing,
link |
00:35:06.800
and then I fill it in with examples later.
link |
00:35:08.800
Always, it will be more compelling
link |
00:35:10.800
and easier to understand when you flip that.
link |
00:35:12.800
And instead, you let someone's brain
link |
00:35:14.800
do the pattern recognition.
link |
00:35:16.800
You just show them a bunch of examples.
link |
00:35:18.800
You're always going to feel a certain similarity between them.
link |
00:35:20.800
Then by the time you bring in the definition,
link |
00:35:22.800
or by the time you bring in the formula,
link |
00:35:24.800
it's articulating a thing
link |
00:35:26.800
that's already in the brain
link |
00:35:28.800
that was built off of looking at a bunch of examples
link |
00:35:30.800
with a certain kind of similarity.
link |
00:35:32.800
And what the formula does is articulate
link |
00:35:34.800
what that kind of similarity is,
link |
00:35:36.800
rather than being
link |
00:35:38.800
a high cognitive load
link |
00:35:40.800
set of symbols that needs to be
link |
00:35:42.800
populated with examples later on,
link |
00:35:44.800
assuming someone's still with you.
link |
00:35:46.800
What is the most beautiful
link |
00:35:48.800
or awe inspiring idea
link |
00:35:50.800
you've come across in mathematics?
link |
00:35:52.800
I don't know, man.
link |
00:35:54.800
Maybe it's an idea you've explored in your videos,
link |
00:35:56.800
maybe not.
link |
00:35:58.800
What just gave you pause?
link |
00:36:00.800
What's the most beautiful idea?
link |
00:36:02.800
Small or big.
link |
00:36:04.800
So I think often the things that are most beautiful
link |
00:36:06.800
are the ones that you
link |
00:36:08.800
have a little bit of understanding of,
link |
00:36:10.800
but certainly not an entire understanding.
link |
00:36:12.800
It's a little bit of that mystery
link |
00:36:14.800
that is what makes it beautiful.
link |
00:36:16.800
Almost a moment of the discovery
link |
00:36:18.800
for you personally, almost just that
link |
00:36:20.800
leap of a ha ha moment.
link |
00:36:22.800
So something that really caught my eye.
link |
00:36:24.800
I remember when I was little,
link |
00:36:26.800
there were these like,
link |
00:36:28.800
I think the series was called like wooden books
link |
00:36:30.800
or something, these tiny little books that
link |
00:36:32.800
would have just a very short description of something
link |
00:36:34.800
on the left and then a picture on the right.
link |
00:36:36.800
I don't know who they're meant for, but maybe it's like
link |
00:36:38.800
loosely children or something like that.
link |
00:36:40.800
But it can't just be children because of some of the things
link |
00:36:42.800
on the last page of one of them,
link |
00:36:44.800
somewhere tiny in there was this little formula
link |
00:36:46.800
that on the left hand
link |
00:36:48.800
had a sum over all of the natural numbers.
link |
00:36:50.800
You know, it's like one over
link |
00:36:52.800
one to the s plus one over two to the s
link |
00:36:54.800
plus one over three to the s on and on to the infinity.
link |
00:36:56.800
Then on the other side
link |
00:36:58.800
had a product over all of the primes
link |
00:37:00.800
and it was a certain thing had to do with all the primes
link |
00:37:02.800
and
link |
00:37:04.800
like any good young math enthusiast,
link |
00:37:06.800
I'd properly been indoctrinated with how chaotic
link |
00:37:08.800
and confusing the primes are, which they are
link |
00:37:10.800
and seeing this
link |
00:37:12.800
equation where on one side you have something
link |
00:37:14.800
that's as understandable as you could possibly get
link |
00:37:16.800
the counting numbers and on the other side
link |
00:37:18.800
is all the prime numbers. It was like this.
link |
00:37:20.800
Whoa!
link |
00:37:22.800
They're related like this?
link |
00:37:24.800
There's a simple description that includes
link |
00:37:26.800
all the primes getting wrapped together like this.
link |
00:37:28.800
This is like the Euler product
link |
00:37:30.800
for the zeta function as I later found out.
link |
00:37:32.800
The equation itself
link |
00:37:34.800
essentially encodes the fundamental theorem
link |
00:37:36.800
of arithmetic that every number can be expressed
link |
00:37:38.800
as a unique set of primes.
link |
00:37:40.800
To me still,
link |
00:37:42.800
I certainly don't understand this equation
link |
00:37:44.800
or this function all that well.
link |
00:37:46.800
The more I learn about it, the prettier it is.
link |
00:37:48.800
The idea that
link |
00:37:50.800
this is sort of what gets you
link |
00:37:52.800
representations of primes
link |
00:37:54.800
not in terms of primes themselves
link |
00:37:56.800
but in terms of another set of numbers
link |
00:37:58.800
that are like the non trivial zeros of the zeta function.
link |
00:38:00.800
Again, I'm very
link |
00:38:02.800
kind of in over my head in a lot of ways
link |
00:38:04.800
as I try to get to understand it.
link |
00:38:06.800
But the more I do,
link |
00:38:08.800
it always leaves enough mystery
link |
00:38:10.800
that it remains very beautiful to me.
link |
00:38:12.800
Whenever there's a little bit of mystery
link |
00:38:14.800
just outside of the understanding
link |
00:38:16.800
and by the way,
link |
00:38:18.800
the process of learning more about it,
link |
00:38:20.800
how does that come about?
link |
00:38:22.800
Just your own thought or are you
link |
00:38:24.800
reading?
link |
00:38:26.800
Or is the process of visualization itself
link |
00:38:28.800
revealing more to you?
link |
00:38:30.800
Visuals help.
link |
00:38:32.800
In one time when I was just trying to understand
link |
00:38:34.800
utilizing complex functions,
link |
00:38:36.800
this is what led to a video
link |
00:38:38.800
about this function.
link |
00:38:40.800
It's titled something like visualizing the Riemann zeta function.
link |
00:38:42.800
It's one that came about because
link |
00:38:44.800
I was programming and
link |
00:38:46.800
tried to see what a certain thing looked like
link |
00:38:48.800
and then I looked at it and I'm like,
link |
00:38:50.800
whoa, that's elucidating.
link |
00:38:52.800
And then I decided to make a video about it.
link |
00:38:54.800
But,
link |
00:38:56.800
I mean, you try to
link |
00:38:58.800
get your hands on as much reading as you can.
link |
00:39:00.800
You,
link |
00:39:02.800
if they have like a
link |
00:39:04.800
math background of some, like they studied some
link |
00:39:06.800
in college or something like that,
link |
00:39:08.800
like the Princeton companion to math has a really good article
link |
00:39:10.800
on analytic number theory
link |
00:39:12.800
and that itself has a whole bunch of references
link |
00:39:14.800
and, you know, anything has
link |
00:39:16.800
more references and it gives you this, like, tree
link |
00:39:18.800
to start plying through.
link |
00:39:20.800
And, like, you know, you try to understand,
link |
00:39:22.800
I try to understand things visually as I go.
link |
00:39:24.800
That's not always possible,
link |
00:39:26.800
but it's very helpful when it does.
link |
00:39:28.800
You recognize when there's common themes,
link |
00:39:30.800
cousins of the Fourier transform,
link |
00:39:32.800
like, coming to play,
link |
00:39:34.800
and you realize, oh, it's probably pretty important
link |
00:39:36.800
to have deep intuitions of the Fourier transform,
link |
00:39:38.800
even if it's not explicitly mentioned
link |
00:39:40.800
in, like, these texts.
link |
00:39:42.800
And you try to get a sense of what the common players are.
link |
00:39:44.800
But I'll emphasize again, like,
link |
00:39:46.800
I feel very in over my head
link |
00:39:48.800
when I try to understand
link |
00:39:50.800
the exact relation between,
link |
00:39:52.800
like, the zeros of the Riemann Zeta function
link |
00:39:54.800
and how they relate to the distribution of primes.
link |
00:39:56.800
I definitely understand it better than I did a year ago.
link |
00:39:58.800
I definitely understand it one one hundredth
link |
00:40:00.800
as well as the experts on the matter do,
link |
00:40:02.800
I assume.
link |
00:40:04.800
But the slow path
link |
00:40:06.800
towards getting there is, it's fun,
link |
00:40:08.800
it's charming, and, like, to your question,
link |
00:40:10.800
very beautiful.
link |
00:40:12.800
And the beauty is in the, what,
link |
00:40:14.800
in the journey versus the destination?
link |
00:40:16.800
Well, it's that each thing doesn't feel arbitrary.
link |
00:40:18.800
I think that's a big part.
link |
00:40:20.800
Is that you have these unpredictable,
link |
00:40:22.800
yeah, these very unpredictable patterns
link |
00:40:24.800
where these intricate
link |
00:40:26.800
properties of, like, a certain function.
link |
00:40:28.800
But at the same time, it doesn't feel like
link |
00:40:30.800
humans ever made an arbitrary choice
link |
00:40:32.800
in studying this particular thing.
link |
00:40:34.800
So, you know, it feels like
link |
00:40:36.800
you're speaking to patterns themselves
link |
00:40:38.800
or nature itself.
link |
00:40:40.800
That's a big part of it.
link |
00:40:42.800
I think things that are too arbitrary,
link |
00:40:44.800
it's just hard for those to feel beautiful because
link |
00:40:46.800
this is sort of what the word
link |
00:40:48.800
contrived is meant to apply to, right?
link |
00:40:52.800
And when they're not arbitrary,
link |
00:40:54.800
it means it could be
link |
00:40:56.800
you can have a clean
link |
00:40:58.800
abstraction
link |
00:41:00.800
and intuition
link |
00:41:02.800
that allows you to comprehend it.
link |
00:41:04.800
Well, to one of your first questions,
link |
00:41:06.800
it makes you feel like if you came across
link |
00:41:08.800
another intelligent civilization,
link |
00:41:10.800
that they'd be studying the same thing.
link |
00:41:12.800
Maybe with different notation.
link |
00:41:14.800
Certainly, yeah.
link |
00:41:16.800
I think you talked to that other civilization.
link |
00:41:18.800
They're probably also studying the zeroes
link |
00:41:20.800
of the Riemann Zeta function.
link |
00:41:22.800
There's some variant thereof
link |
00:41:24.800
that is like a
link |
00:41:26.800
clearly equivalent cousin or something like that.
link |
00:41:28.800
But that's probably on their
link |
00:41:30.800
docket.
link |
00:41:32.800
Whenever somebody does a lot of something
link |
00:41:34.800
amazing,
link |
00:41:36.800
I'm going to ask the question
link |
00:41:38.800
that you've already been asked a lot,
link |
00:41:40.800
that you'll get more and more asked in your life.
link |
00:41:42.800
But what was your favorite
link |
00:41:44.800
video to create?
link |
00:41:46.800
Oh, favorite to create.
link |
00:41:48.800
One of my favorites is
link |
00:41:50.800
the title is Who Cares about Topology.
link |
00:41:52.800
Do you want me to pull it up?
link |
00:41:54.800
If you want, sure.
link |
00:41:56.800
It is about
link |
00:41:58.800
it starts by describing
link |
00:42:00.800
an unsolved problem that's still unsolved in math
link |
00:42:02.800
called the inscribed square problem.
link |
00:42:04.800
You draw any loop and then you ask,
link |
00:42:06.800
are there four points on that loop that make a square?
link |
00:42:08.800
Totally useless, right? This is not
link |
00:42:10.800
answering any physical questions.
link |
00:42:12.800
It's mostly interesting that we can't answer that question.
link |
00:42:14.800
And it seems like such a natural thing to ask.
link |
00:42:16.800
Now, if you
link |
00:42:18.800
weaken it a little bit and you ask,
link |
00:42:20.800
can you always find a rectangle?
link |
00:42:22.800
You choose four points on this curve.
link |
00:42:24.800
Can you find a rectangle? That's hard.
link |
00:42:26.800
But it's doable and the path to it
link |
00:42:28.800
involves
link |
00:42:30.800
things like looking at a
link |
00:42:32.800
torus, this surface with a single hole in it,
link |
00:42:34.800
like a donut, or looking at a mobius strip
link |
00:42:36.800
in ways that feel so much less contrived
link |
00:42:38.800
to when I first,
link |
00:42:40.800
as like a little kid, learned about these surfaces
link |
00:42:42.800
and shapes, like a mobius strip and a torus.
link |
00:42:44.800
Like what you learn is,
link |
00:42:46.800
oh, this mobius strip, you take a piece of paper,
link |
00:42:48.800
put a twist, glue it together,
link |
00:42:50.800
and now you have a shape with one edge and just one side.
link |
00:42:52.800
And
link |
00:42:54.800
as a student, you should think,
link |
00:42:56.800
who cares, right?
link |
00:42:58.800
How does that help me solve any problems?
link |
00:43:00.800
I thought math was about problem solving.
link |
00:43:02.800
So what I liked about
link |
00:43:04.800
the piece of math that this was describing
link |
00:43:06.800
that was in this paper
link |
00:43:08.800
by a mathematician named Vaughn,
link |
00:43:10.800
was that it arises very naturally.
link |
00:43:12.800
It's clear what it represents.
link |
00:43:14.800
It's not just doing something.
link |
00:43:16.800
It's not just playing with construction paper.
link |
00:43:18.800
And the way that it solves the problem
link |
00:43:20.800
is really beautiful.
link |
00:43:22.800
So kind of putting all of that down
link |
00:43:24.800
and concretizing it, right?
link |
00:43:26.800
Like I was talking about how
link |
00:43:28.800
when you have to put visuals to it,
link |
00:43:30.800
it demands that what's on screen is a very specific
link |
00:43:32.800
example of what you're describing.
link |
00:43:34.800
The construction here is very abstract in nature.
link |
00:43:36.800
You describe this very abstract kind of surface
link |
00:43:38.800
in 3D space.
link |
00:43:40.800
So then when I was finding myself,
link |
00:43:42.800
a graph that's built into OSX
link |
00:43:44.800
for the 3D stuff,
link |
00:43:46.800
to draw that surface,
link |
00:43:48.800
you realize, oh man, the topology argument
link |
00:43:50.800
is very nonconstructive.
link |
00:43:52.800
You have to do a lot of extra work
link |
00:43:54.800
in order to make the surface show up.
link |
00:43:56.800
But then once you see it, it's quite pretty
link |
00:43:58.800
and it's very satisfying to see a specific instance of it.
link |
00:44:00.800
And you also feel like,
link |
00:44:02.800
ah, I've actually added something
link |
00:44:04.800
on top of what the original paper was doing,
link |
00:44:06.800
that it shows something that's completely correct.
link |
00:44:08.800
It's a very beautiful argument,
link |
00:44:10.800
but you don't see what it looks like.
link |
00:44:12.800
And I found something satisfying
link |
00:44:14.800
in seeing what it looked like
link |
00:44:16.800
that could only ever come about from the forcing function
link |
00:44:18.800
of getting some kind of image on the screen
link |
00:44:20.800
to describe the thing I was talking about.
link |
00:44:22.800
So you almost weren't able to anticipate what it's going to look like.
link |
00:44:24.800
I had no idea.
link |
00:44:26.800
And it was wonderful.
link |
00:44:28.800
It looks like a Sydney Opera House
link |
00:44:30.800
or some sort of Frank Gary design.
link |
00:44:32.800
You knew it was going to be something
link |
00:44:34.800
and you can say various things about it,
link |
00:44:36.800
like, oh, it touches the curve itself.
link |
00:44:38.800
It has a boundary that's this curve on the 2D plane.
link |
00:44:40.800
It all sits above the plane.
link |
00:44:42.800
But before you actually draw it,
link |
00:44:44.800
it's very unclear what the thing will look like.
link |
00:44:46.800
And to see it, it's very,
link |
00:44:48.800
it's just pleasing, right?
link |
00:44:50.800
So that was fun to make, very fun to share.
link |
00:44:52.800
I hope that it has elucidated
link |
00:44:54.800
for some people out there
link |
00:44:56.800
where these constructs of topology come from,
link |
00:44:58.800
that it's not arbitrary play
link |
00:45:00.800
with construction paper.
link |
00:45:02.800
So let's, I think this is a good,
link |
00:45:04.800
a good sort of example
link |
00:45:06.800
to talk a little bit about your process.
link |
00:45:08.800
So you have a list of ideas.
link |
00:45:10.800
So that's sort of the
link |
00:45:12.800
the curse of having
link |
00:45:14.800
having an active and brilliant mind
link |
00:45:16.800
is I'm sure you have a list
link |
00:45:18.800
that's growing faster than you can utilize.
link |
00:45:20.800
Now on the head.
link |
00:45:22.800
Absolutely.
link |
00:45:24.800
But there's some sorting procedure
link |
00:45:26.800
depending on mood and interest and so on.
link |
00:45:28.800
But okay, so you pick an idea
link |
00:45:30.800
and then you have to try
link |
00:45:32.800
to write a narrative arc
link |
00:45:34.800
that's sort of
link |
00:45:36.800
how do I elucidate out?
link |
00:45:38.800
How do I make this idea beautiful
link |
00:45:40.800
and clear and explain it?
link |
00:45:42.800
And then there's a set of visualizations
link |
00:45:44.800
that will be attached to it.
link |
00:45:46.800
You've talked about some of this before
link |
00:45:48.800
about sort of writing the story
link |
00:45:50.800
attaching the visualizations.
link |
00:45:52.800
Can you talk through
link |
00:45:54.800
interesting, painful,
link |
00:45:56.800
beautiful parts of that process?
link |
00:45:58.800
Well, the most painful is
link |
00:46:00.800
if you've chosen a topic that you do want to do,
link |
00:46:02.800
but then it's hard to think of
link |
00:46:04.800
I guess how to structure the script.
link |
00:46:06.800
This is
link |
00:46:08.800
sort of where I have been on one for like
link |
00:46:10.800
the last two or three months and I think
link |
00:46:12.800
ultimately the right resolution is just like set it aside
link |
00:46:14.800
and instead do some other things
link |
00:46:16.800
where the script comes more naturally.
link |
00:46:18.800
Because you sort of don't want to overwork
link |
00:46:20.800
a narrative
link |
00:46:22.800
that the more you've thought about it
link |
00:46:24.800
the less you can empathize with the student
link |
00:46:26.800
who doesn't yet understand the thing you're trying to teach.
link |
00:46:28.800
Who is the judge in your head?
link |
00:46:30.800
Sort of the person,
link |
00:46:32.800
the creature,
link |
00:46:34.800
the essence that's saying
link |
00:46:36.800
this sucks or this is good.
link |
00:46:38.800
And you mentioned kind of the student
link |
00:46:40.800
you're thinking about.
link |
00:46:42.800
Who is that?
link |
00:46:44.800
What is that thing?
link |
00:46:46.800
That says the perfectionist
link |
00:46:48.800
that says this thing sucks
link |
00:46:50.800
you need to work on it for another two, three months.
link |
00:46:52.800
I don't know.
link |
00:46:54.800
I think it's my past self.
link |
00:46:56.800
I think that's the entity that I'm most trying to empathize with
link |
00:46:58.800
is like you take
link |
00:47:00.800
because that's kind of the only person I know.
link |
00:47:02.800
You don't really know anyone other than versions of yourself.
link |
00:47:04.800
So I start with the version of myself
link |
00:47:06.800
that I know who doesn't yet understand the thing.
link |
00:47:08.800
And then
link |
00:47:10.800
I just try to
link |
00:47:12.800
view it with fresh eyes
link |
00:47:14.800
a particular visual or a particular script.
link |
00:47:16.800
Is this motivating? Does this make sense?
link |
00:47:18.800
Which has its downsides
link |
00:47:20.800
because sometimes I find myself
link |
00:47:22.800
speaking to motivations
link |
00:47:24.800
that only myself
link |
00:47:26.800
would be interested in.
link |
00:47:28.800
I did this project on quaternions
link |
00:47:30.800
where what I really wanted
link |
00:47:32.800
was to understand what are they doing in four dimensions.
link |
00:47:34.800
Can we see what they're doing in four dimensions?
link |
00:47:36.800
And I
link |
00:47:38.800
had a way of thinking about it
link |
00:47:40.800
that really answered the question in my head
link |
00:47:42.800
that made me very satisfied and being able to think about
link |
00:47:44.800
concretely with a 3D visual
link |
00:47:46.800
what are they doing to a 4D sphere?
link |
00:47:48.800
And so I'm like great this is exactly what my past self
link |
00:47:50.800
would have wanted and I make a thing on it
link |
00:47:52.800
and I'm sure it's what some other people wanted too.
link |
00:47:54.800
But in hindsight I think most people
link |
00:47:56.800
who want to learn about quaternions
link |
00:47:58.800
are robotics engineers
link |
00:48:00.800
or graphics programmers
link |
00:48:02.800
who want to understand how they're used
link |
00:48:04.800
to describe 3D rotations
link |
00:48:06.800
and their use case was actually a little bit different
link |
00:48:08.800
than my past self and in that way
link |
00:48:10.800
I wouldn't actually recommend that video to
link |
00:48:12.800
people who are coming at it from that angle
link |
00:48:14.800
of wanting to know hey I'm a robotics programmer
link |
00:48:16.800
how do these quaternion things
link |
00:48:18.800
work to describe
link |
00:48:20.800
position in 3D space.
link |
00:48:22.800
I would say other great resources
link |
00:48:24.800
for that if you ever find yourself
link |
00:48:26.800
wanting to say like but hang on
link |
00:48:28.800
in what sense are they acting in 4 dimensions
link |
00:48:30.800
then come back but until then
link |
00:48:32.800
it's a little different.
link |
00:48:34.800
Yeah it's interesting because
link |
00:48:36.800
you have incredible videos on neural networks
link |
00:48:38.800
for example and from my sort of
link |
00:48:40.800
perspective because I've probably
link |
00:48:42.800
I mean I looked at the
link |
00:48:44.800
it is sort of my field
link |
00:48:46.800
and I've also looked at the basic
link |
00:48:48.800
introduction of neural networks like a million
link |
00:48:50.800
times from different perspectives
link |
00:48:52.800
and it made me realize that there's a lot of ways
link |
00:48:54.800
to present it so if you were sort of
link |
00:48:56.800
you did an incredible job
link |
00:48:58.800
I mean sort of the
link |
00:49:00.800
but you could also do it
link |
00:49:02.800
differently and also incredible
link |
00:49:04.800
like to create
link |
00:49:06.800
a beautiful presentation
link |
00:49:08.800
of a basic concept
link |
00:49:10.800
is requires sort of
link |
00:49:12.800
creativity requires genius
link |
00:49:14.800
and so on but you can take it
link |
00:49:16.800
from a bunch of different perspectives
link |
00:49:18.800
and you realize that
link |
00:49:20.800
and just as you're saying
link |
00:49:22.800
you kind of have a certain mindset
link |
00:49:24.800
a certain view but
link |
00:49:26.800
if you take a different view
link |
00:49:28.800
from a physics perspective
link |
00:49:30.800
from a neuroscience
link |
00:49:32.800
perspective talking about neural networks
link |
00:49:34.800
or from
link |
00:49:36.800
a robotics perspective
link |
00:49:38.800
or from let's see
link |
00:49:40.800
from a pure learning theory
link |
00:49:42.800
statistics perspective so you can create
link |
00:49:44.800
totally different videos
link |
00:49:46.800
with a few actually concepts
link |
00:49:48.800
where you have taken different concepts
link |
00:49:50.800
at the
link |
00:49:52.800
at the Euler equation
link |
00:49:54.800
you've taken different views of that
link |
00:49:56.800
I think I've made three videos on it
link |
00:49:58.800
and I definitely will make at least one more
link |
00:50:00.800
never enough
link |
00:50:02.800
never enough so you don't think it's
link |
00:50:04.800
the most beautiful equation in mathematics
link |
00:50:06.800
like I said
link |
00:50:08.800
as we represent it it's one of the most hideous
link |
00:50:10.800
it involves a lot of the most hideous
link |
00:50:12.800
aspects of our notation I talked about E
link |
00:50:14.800
the fact that we use pi instead of tau
link |
00:50:16.800
the fact that we
link |
00:50:18.800
call imaginary numbers imaginary
link |
00:50:20.800
and then actually wonder
link |
00:50:22.800
if we use the I because of imaginary
link |
00:50:24.800
I don't know if that's historically accurate
link |
00:50:26.800
but at least a lot of people they read the I
link |
00:50:28.800
and they think imaginary
link |
00:50:30.800
like all three of those facts it's like
link |
00:50:32.800
those are things that have added more confusion than they needed to
link |
00:50:34.800
and we're wrapping them up in one equation
link |
00:50:36.800
like boy that's just very hideous
link |
00:50:38.800
the ideas that it does
link |
00:50:40.800
tie together when you wash away the notation
link |
00:50:42.800
it's pretty it's nice
link |
00:50:44.800
but it's not like
link |
00:50:46.800
mind blowing greatest thing in the universe
link |
00:50:48.800
which is maybe what I was thinking of when I said
link |
00:50:50.800
like once you understand
link |
00:50:52.800
something it doesn't have the same
link |
00:50:54.800
beauty like I feel like I understand
link |
00:50:56.800
Euler's formula
link |
00:50:58.800
and I feel like I understand it enough to
link |
00:51:00.800
sort of see the
link |
00:51:02.800
the version that just woke up
link |
00:51:04.800
that hasn't really gotten itself dressed
link |
00:51:06.800
in the morning that's a little bit groggy and there's
link |
00:51:08.800
bags under its eyes
link |
00:51:10.800
you're past the dating
link |
00:51:12.800
stage and you're no longer dating
link |
00:51:14.800
I'm still dating the Zeta function
link |
00:51:16.800
and she's beautiful
link |
00:51:18.800
and we have fun
link |
00:51:20.800
and it's that high dopamine part
link |
00:51:22.800
but maybe at some point we'll settle into
link |
00:51:24.800
the more mundane nature of the relationship
link |
00:51:26.800
where I see her for who she truly is
link |
00:51:28.800
and she'll still be beautiful in her own way
link |
00:51:30.800
but it won't have the same romantic
link |
00:51:32.800
pizzazz
link |
00:51:34.800
that's the nice thing about mathematics
link |
00:51:36.800
as long as you don't live forever
link |
00:51:38.800
there will always be
link |
00:51:40.800
enough mystery and fun with some of the equations
link |
00:51:42.800
even if you do
link |
00:51:44.800
the rate at which questions comes up is much faster
link |
00:51:46.800
than the rate at which answers come up so
link |
00:51:48.800
if you could live forever would you
link |
00:51:50.800
I think so yeah
link |
00:51:52.800
you don't think mortality is the thing that makes life
link |
00:51:54.800
meaningful
link |
00:51:56.800
would your life be four times as meaningful
link |
00:51:58.800
if you died at 25
link |
00:52:00.800
so this goes to infinity
link |
00:52:02.800
I think you and I
link |
00:52:04.800
that's really interesting so what I said is infinite
link |
00:52:06.800
not four times longer
link |
00:52:08.800
it's an infinite
link |
00:52:10.800
so the actual existence
link |
00:52:12.800
of the finiteness
link |
00:52:14.800
the existence of the end
link |
00:52:16.800
no matter the length
link |
00:52:18.800
is the thing that may
link |
00:52:20.800
for my comprehension of psychology
link |
00:52:22.800
it's such a deeply
link |
00:52:24.800
human
link |
00:52:26.800
it's such a fundamental part of the human condition
link |
00:52:28.800
the fact that we're mortal
link |
00:52:30.800
that
link |
00:52:32.800
the fact that things end
link |
00:52:34.800
seems to be a crucial part of what gives them
link |
00:52:36.800
meaning
link |
00:52:38.800
at least for me
link |
00:52:40.800
it's a very small percentage of my time
link |
00:52:42.800
that mortality is salient
link |
00:52:44.800
that I'm aware of the end of my life
link |
00:52:46.800
what do you mean by me
link |
00:52:48.800
I'm trolling
link |
00:52:50.800
is it the ego, is it the id
link |
00:52:52.800
or is it the superego
link |
00:52:54.800
the reflective self
link |
00:52:56.800
the vernici's area that puts all this stuff
link |
00:52:58.800
into words
link |
00:53:00.800
a small percentage of your mind
link |
00:53:02.800
is actually aware of the true
link |
00:53:04.800
motivations that drive you
link |
00:53:06.800
but my point is that most of my life
link |
00:53:08.800
I'm not thinking about death
link |
00:53:10.800
but I still feel very motivated to make things
link |
00:53:12.800
and to interact with people
link |
00:53:14.800
like experience love or things like that
link |
00:53:16.800
I'm very motivated
link |
00:53:18.800
and it's strange that that motivation comes
link |
00:53:20.800
while death is not in my mind at all
link |
00:53:22.800
and this might just be because I'm young enough
link |
00:53:24.800
that it's not salient
link |
00:53:26.800
or it's in your subconscious
link |
00:53:28.800
or that you construct an illusion
link |
00:53:30.800
of reality by enjoying the moment
link |
00:53:32.800
sort of the existential approach life
link |
00:53:34.800
could be
link |
00:53:36.800
gun to my head, I don't think that's it
link |
00:53:38.800
another sort of way to say gun to the head
link |
00:53:40.800
is sort of the deep psychological
link |
00:53:42.800
introspection of what drives us
link |
00:53:44.800
in some ways to me
link |
00:53:46.800
when I look at math, when I look at science
link |
00:53:48.800
is it kind of an escape from reality
link |
00:53:50.800
in a sense that
link |
00:53:52.800
it's so beautiful
link |
00:53:54.800
it's such a beautiful
link |
00:53:56.800
journey of discovery
link |
00:53:58.800
that it allows you to actually
link |
00:54:00.800
it allows you to achieve
link |
00:54:02.800
a kind of immortality
link |
00:54:04.800
of
link |
00:54:06.800
explore ideas
link |
00:54:08.800
and sort of connect yourself to the thing
link |
00:54:10.800
that is seemingly infinite
link |
00:54:12.800
like the universe
link |
00:54:14.800
that it allows you to escape
link |
00:54:16.800
the limited nature
link |
00:54:18.800
of our little
link |
00:54:20.800
of our bodies, of our existence
link |
00:54:22.800
what else would give this podcast meaning?
link |
00:54:24.800
that's right
link |
00:54:26.800
the fact that it will end
link |
00:54:28.800
this place closes in 40 minutes
link |
00:54:30.800
and it's so much more meaningful for it
link |
00:54:32.800
how much more
link |
00:54:34.800
I love this room because we'll be kicked out
link |
00:54:36.800
so
link |
00:54:38.800
I understand
link |
00:54:40.800
just because you're trolling me
link |
00:54:42.800
doesn't mean I'm wrong
link |
00:54:44.800
so
link |
00:54:46.800
but I take your point
link |
00:54:48.800
boy that would be a good Twitter bio
link |
00:54:50.800
just because
link |
00:54:52.800
you're trolling me doesn't mean I'm wrong
link |
00:54:54.800
and
link |
00:54:56.800
difference in backgrounds
link |
00:54:58.800
I'm a bit Russian so we're a bit
link |
00:55:00.800
melancholic and seem to maybe
link |
00:55:02.800
assign a little too much value to
link |
00:55:04.800
suffering immortality and things like that
link |
00:55:06.800
makes for a better novel I think
link |
00:55:08.800
oh yeah, you need
link |
00:55:10.800
some sort of existential threat
link |
00:55:12.800
to drive a plot
link |
00:55:14.800
so when do you know when the video is done
link |
00:55:16.800
when you're working on it?
link |
00:55:18.800
that's pretty easy actually
link |
00:55:20.800
because
link |
00:55:22.800
I'll write the script
link |
00:55:24.800
I want there to be some kind of aha moment
link |
00:55:26.800
and then hopefully the script can revolve around
link |
00:55:28.800
some kind of aha moment
link |
00:55:30.800
and then from there you're putting visuals
link |
00:55:32.800
to each sentence that exists
link |
00:55:34.800
and then you narrate it, you edit it all together
link |
00:55:36.800
so given that there's a script
link |
00:55:38.800
the end becomes quite clear
link |
00:55:40.800
and as I
link |
00:55:42.800
animate it I often change
link |
00:55:44.800
certainly the specific words
link |
00:55:46.800
but sometimes the structure itself
link |
00:55:48.800
but it's a very
link |
00:55:50.800
deterministic process at that point
link |
00:55:52.800
it makes it much easier to predict when something
link |
00:55:54.800
will be done. How do you know when a script is
link |
00:55:56.800
done? For problem solving videos
link |
00:55:58.800
that's quite simple, it's once you feel
link |
00:56:00.800
like someone who didn't understand the solution now
link |
00:56:02.800
could. For things like neural networks
link |
00:56:04.800
that was a lot harder because like you said
link |
00:56:06.800
there's so many angles at which you could attack it
link |
00:56:08.800
and there it's
link |
00:56:10.800
just at some point you feel like
link |
00:56:12.800
this asks
link |
00:56:14.800
a meaningful question and it answers that question
link |
00:56:16.800
right?
link |
00:56:18.800
What is the best way to learn math for people
link |
00:56:20.800
who might be at the beginning of that journey?
link |
00:56:22.800
I think that's a question that a lot of folks
link |
00:56:24.800
kind of ask and think about
link |
00:56:26.800
and it doesn't even for folks who are not really
link |
00:56:28.800
at the beginning of their journey
link |
00:56:30.800
there might be actually
link |
00:56:32.800
deep in their career
link |
00:56:34.800
type of technology taking calculus and so on
link |
00:56:36.800
but still want to sort of explore math
link |
00:56:38.800
what would be your advice
link |
00:56:40.800
instead of education at all ages?
link |
00:56:42.800
Your temptation will be to
link |
00:56:44.800
spend more time like watching lectures
link |
00:56:46.800
reading
link |
00:56:48.800
try to force yourself to do more problems
link |
00:56:50.800
than you naturally would.
link |
00:56:52.800
That's a big one.
link |
00:56:54.800
The focus time that you're spending should be
link |
00:56:56.800
on solving specific problems
link |
00:56:58.800
and seek entities that have well
link |
00:57:00.800
curated lists of problems.
link |
00:57:02.800
So going to like a textbook almost
link |
00:57:04.800
and the problems in the back of a textbook
link |
00:57:06.800
and the back of a chapter.
link |
00:57:08.800
So if you can take a little look through those
link |
00:57:10.800
questions at the end of the chapter before you read the chapter
link |
00:57:12.800
a lot of them won't make sense. Some of them might
link |
00:57:14.800
those are the best ones to think about.
link |
00:57:16.800
A lot of them won't but just take a quick look
link |
00:57:18.800
and then read a little bit of the chapter and then maybe
link |
00:57:20.800
take a look again and things like that.
link |
00:57:22.800
And don't consider yourself done with the chapter
link |
00:57:24.800
until you've actually worked
link |
00:57:26.800
through a couple exercises.
link |
00:57:28.800
And this is so hypocritical
link |
00:57:30.800
because I put out videos that
link |
00:57:32.800
pretty much never have associated
link |
00:57:34.800
exercises. I just view myself
link |
00:57:36.800
as a different part of the ecosystem
link |
00:57:38.800
which means I'm kind of admitting
link |
00:57:40.800
that you're not really learning
link |
00:57:42.800
or at least this is only a partial part
link |
00:57:44.800
of the learning process if you're watching these videos.
link |
00:57:48.800
I think if someone's at the very beginning
link |
00:57:50.800
like I do think Khan Academy does a good job
link |
00:57:52.800
they have a pretty large set of
link |
00:57:54.800
questions you can work through.
link |
00:57:56.800
Just a very basic sort of
link |
00:57:58.800
just picking up getting comfortable
link |
00:58:00.800
with a very basic linear algebra or calculus
link |
00:58:02.800
on Khan Academy.
link |
00:58:04.800
Programming is actually I think a great
link |
00:58:06.800
like learn to program and like
link |
00:58:08.800
let the way that math is motivated from that
link |
00:58:10.800
through. I know a lot of people who
link |
00:58:12.800
didn't like math got into programming
link |
00:58:14.800
in some way and that's what turned them on to math.
link |
00:58:16.800
Maybe I'm biased because like I live in the Bay Area
link |
00:58:18.800
so I'm more likely to run into someone
link |
00:58:20.800
who has that phenotype
link |
00:58:22.800
but I am
link |
00:58:24.800
willing to speculate that that is a more generalizable path.
link |
00:58:26.800
So you yourself
link |
00:58:28.800
kind of in creating videos are using
link |
00:58:30.800
programming to illuminate a concept
link |
00:58:32.800
but for yourself as well.
link |
00:58:34.800
So would you recommend somebody try to
link |
00:58:36.800
make a sort of almost like
link |
00:58:38.800
try to make videos?
link |
00:58:40.800
So one thing I've heard before
link |
00:58:42.800
I don't know if this is based on any actual study
link |
00:58:44.800
this might be like a total fictional anecdote of
link |
00:58:46.800
numbers but it rings in the mind as
link |
00:58:48.800
being true. You remember about 10%
link |
00:58:50.800
of what you read. You remember about 20%
link |
00:58:52.800
of what you listen to. You remember
link |
00:58:54.800
about 70% of what you actively interact
link |
00:58:56.800
with in some way and then about 90%
link |
00:58:58.800
of what you teach.
link |
00:59:00.800
I think I heard again those numbers might be
link |
00:59:02.800
meaningless but they ring true don't they?
link |
00:59:04.800
I'm willing to say I
link |
00:59:06.800
learned nine times better from teaching something
link |
00:59:08.800
than reading. That might even be a low ball.
link |
00:59:10.800
So doing something to teach
link |
00:59:12.800
or to like actively try to explain things
link |
00:59:14.800
is huge for consolidating the knowledge.
link |
00:59:16.800
Outside of family and friends
link |
00:59:18.800
is there a moment you can
link |
00:59:20.800
remember that you would like
link |
00:59:22.800
to relive because it made you truly happy
link |
00:59:24.800
or it was
link |
00:59:26.800
transformative in some
link |
00:59:28.800
fundamental way? A moment that was
link |
00:59:30.800
transformative.
link |
00:59:32.800
Or made you truly happy?
link |
00:59:34.800
Yeah, I think there's times
link |
00:59:36.800
music used to be a much bigger part of my life
link |
00:59:38.800
than it is now. Like when I was a
link |
00:59:40.800
teenager and I can think of
link |
00:59:42.800
sometimes in like playing music
link |
00:59:44.800
there was one
link |
00:59:46.800
my brother and a friend of mine so this
link |
00:59:48.800
slightly violates the family and friends but
link |
00:59:50.800
there was music that made me happy. They were just
link |
00:59:52.800
accompanying.
link |
00:59:54.800
We played a gig at a ski resort
link |
00:59:56.800
such that you take a gondola
link |
00:59:58.800
to the top and did a thing
link |
01:00:00.800
and then on the gondola right down we decided to just jam
link |
01:00:02.800
a little bit and
link |
01:00:04.800
it was just like, I don't know, the gondola
link |
01:00:06.800
sort of over came over a mountain
link |
01:00:08.800
and you saw the city lights
link |
01:00:10.800
and we're just like jamming, like playing some
link |
01:00:12.800
music. I wouldn't describe that as
link |
01:00:14.800
transformative. I don't know why
link |
01:00:16.800
but that popped into my mind as a moment of
link |
01:00:18.800
in a way that wasn't associated
link |
01:00:20.800
with people I love but more with like a thing
link |
01:00:22.800
I was doing, something that was
link |
01:00:24.800
just, it was just happy and it was just like
link |
01:00:26.800
a great moment.
link |
01:00:28.800
I don't think I can give you anything deeper than
link |
01:00:30.800
that though. Well as a musician
link |
01:00:32.800
myself, I'd love to see
link |
01:00:34.800
as you mentioned before
link |
01:00:36.800
music enter back into your work
link |
01:00:38.800
back into your creative work. I'd love to see that
link |
01:00:40.800
I'm certainly allowing it
link |
01:00:42.800
to enter back into mine and it's
link |
01:00:44.800
a beautiful thing
link |
01:00:46.800
for a mathematician, for a scientist
link |
01:00:48.800
to allow music to enter their
link |
01:00:50.800
work. I think only good
link |
01:00:52.800
things can happen. Alright, I'll try to promise
link |
01:00:54.800
you a music video by 2020.
link |
01:00:56.800
By 2020? By the end of 2020.
link |
01:00:58.800
Okay, alright good. I'll give myself a longer window.
link |
01:01:00.800
Alright, maybe
link |
01:01:02.800
we can like collaborate on a
link |
01:01:04.800
band type situation. What instruments do you play?
link |
01:01:06.800
The main instrument I play is violin
link |
01:01:08.800
but I also love to dabble around on like guitar
link |
01:01:10.800
and piano. Beautiful. Me too, guitar
link |
01:01:12.800
and piano.
link |
01:01:14.800
So in a mathematician's
link |
01:01:16.800
lament, Paul Lockhart writes
link |
01:01:18.800
the first thing to understand is that mathematics
link |
01:01:20.800
is an art. The difference between
link |
01:01:22.800
math and the other arts such as
link |
01:01:24.800
music and painting
link |
01:01:26.800
is that our culture does not recognize it
link |
01:01:28.800
as such. So I think I speak
link |
01:01:30.800
for millions of people,
link |
01:01:32.800
myself included,
link |
01:01:34.800
in saying thank you for revealing
link |
01:01:36.800
to us the art of mathematics.
link |
01:01:38.800
So thank you for everything you do
link |
01:01:40.800
and thanks for talking today. Well, thanks
link |
01:01:42.800
for saying that and thanks for having me on.
link |
01:01:44.800
Thanks for listening to this conversation
link |
01:01:46.800
with Grant Sanderson and thank you
link |
01:01:48.800
to our presenting sponsor, Cash App.
link |
01:01:50.800
Download it, use
link |
01:01:52.800
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link |
01:01:54.800
You'll get $10 and $10
link |
01:01:56.800
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link |
01:01:58.800
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link |
01:02:00.800
thousands of young minds to become future
link |
01:02:02.800
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link |
01:02:04.800
If you enjoy this podcast, subscribe
link |
01:02:06.800
on YouTube, give it 5 stars on Apple
link |
01:02:08.800
Podcast, support it on Patreon
link |
01:02:10.800
or connect with me on Twitter.
link |
01:02:12.800
And now, let me leave you
link |
01:02:14.800
with some words of wisdom from one of
link |
01:02:16.800
Grant's and my favorite people,
link |
01:02:18.800
Richard Feynman.
link |
01:02:20.800
Nobody ever figures
link |
01:02:22.800
out what this life is all about
link |
01:02:24.800
and it doesn't matter.
link |
01:02:26.800
Explore the world.
link |
01:02:28.800
Nearly everything is really interesting
link |
01:02:30.800
if you go into it deeply enough.
link |
01:02:32.800
Thank you for listening
link |
01:02:34.800
and good to see you next time.