back to indexSara Walker: The Origin of Life on Earth and Alien Worlds | Lex Fridman Podcast #198
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The following is a conversation with Sarah Walker,
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an astrobiologist and theoretical physicist
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at Arizona State University and the Santa Fe Institute.
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She's interested in the origin of life,
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how to find life on other worlds,
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and in general, the more fundamental question
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of what even life is.
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She seeks to discover the universal laws
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that describe living systems on Earth and elsewhere,
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using physics, biology, and computation.
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Quick mention of our sponsors,
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Athletic Greens, Netsuite, Blinkist, and Magic Spoon.
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Check them out in the description to support this podcast.
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As a side note, let me say that my hope for this podcast
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is to try and alternate between technical
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and non technical discussions,
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to jump from the big picture
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down to specific detailed research
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and back to the big picture,
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and to do so with scientists and non scientists.
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Long term, I hope to alternate between discussions
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of cutting edge research in AI, physics, biology,
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to topics of music, sport, and history,
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and then back to AI, AI is home.
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I hope you come along with me
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for that wild, oscillating journey.
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Some people message me saying to slow down
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since they're falling behind
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on the episodes of this podcast.
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To their disappointment, I have to say
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that I'll probably do more episodes, not less,
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but you really don't need to listen to every episode.
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Just listen to the ones that spark your curiosity.
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Think about it like a party full of strangers.
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You don't have to talk to everyone.
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Just walk over to the ones who look interesting
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and get to know them.
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And if you're lucky,
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that one conversation with a stranger
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might change the direction of your life.
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And it's the short life,
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so be picky with the strangers you talk to
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at this metaphorical party.
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This is the Lux Friedman podcast,
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and here is my conversation with Sarah Walker.
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How did life originate on Earth?
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What are the various hypotheses
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for how life originated on Earth?
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Yeah, so I guess you're asking a historical question,
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which is always a good place to start thinking about life.
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So there's a lot of ideas about how life started on Earth.
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Probably the most popular
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is what's called the RNA world scenario.
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So this idea is probably the one
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that you'll see most reported in the news.
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And is based on the idea that there are molecules
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in our bodies that relay genetic information.
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We know those as DNA, obviously,
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but there's also sort of an intermediary called RNA,
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ribonucleic acid, that also plays the role of proteins.
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And people came up with this idea in the 80s
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that maybe that was the first genetic material
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because it could play both roles
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of being genetic and performing catalysis.
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And then somehow that idea got reduced to this idea
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that there was a molecule that emerged on early Earth
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and underwent Darwinian evolution,
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and that was the start of life.
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So there's a lot of assumptions packed in there
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that we could unpack,
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but that's sort of the leading hypothesis.
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There's also other ideas about life starting as metabolism.
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And so that's more connected
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to the geochemistry of early Earth.
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And it would be kind of more focused on this idea
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that you get some kind of catalytic cycle of molecules
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that can reproduce themselves
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and form some kind of metabolism.
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And then life starts basically as self organization.
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And then you have to explain how evolution comes later.
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Right, so that's the difference between sort of energy
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So like energy and information,
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are those the two kind of things there?
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Yeah, I think that's a good way of putting it.
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It's kind of funny, because I think most of the people
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that think about these things are really disciplinary bias.
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So the people that tend to think about genetics
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come from a biology background
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and they're really evolution focused.
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And so they're worried about
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where does the information come from
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and how does it change over time?
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But they're talking about information in a really narrow way
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where they're talking about a genetic sequence.
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And then most of the people that think about metabolism,
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origins of life scenarios tend to be people like physicists
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or geochemists that are worried about
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what are the energy sources
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and what kinds of organization
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can you get out of those energy sources?
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Okay, so which one is your favorite?
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I don't like either.
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Okay, can we talk about them for a little bit longer though?
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Yeah, no, that's fine.
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So okay, so there's early earth.
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What was that like?
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Was there just mostly covered by oceans?
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Was there heat sources, energy sources?
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So if we talk about the metabolism view
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of the origin of life,
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like where was the source of energy?
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Probably the most popular view
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for where the original life happened on earth
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is hydrothermal vents,
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because they had sufficient energy.
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And so we don't really know a lot about early earth.
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We have some ideas
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about when oceans first formed and things like that,
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but the time of the origin of life is kind of
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not well understood or pinned down
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and the conditions on earth at that time are not well known.
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But a lot of people do think
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that there was probably hydrothermal vents
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which are really hot chemically active regions
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say on the sea floor in modern times,
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which also would have been present on early earth
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and they would have provided energy and organics
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and basically all of the right conditions
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for the origins of life,
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which is one of the reasons
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that we look for these hydrothermal systems
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when we're talking about life elsewhere too.
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Okay, and for the genetic code,
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the idea is that the RNA is the first,
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like why would RNA be the first moment
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you can say it's life?
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I guess the idea is it could both have persistent information
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and then it can also do some of the work
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of like what, creating a self sustaining organism?
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Yeah, that's the basic idea.
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So the idea is you have in an RNA molecule,
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you have a sequence of characters say,
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so you can treat it like a string in a computer
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and it can be copied.
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So information can be propagated,
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which is important for evolution
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because evolution happens
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by having inheritance of information.
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So for example, like my eyes are brown
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because my mother's eyes were brown.
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So you need that copying of information,
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but then you also have the ability to perform catalysis,
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which means that that RNA molecule
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is not inert in that environment,
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but it actually interacts with something
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and could potentially mediate, say a metabolism
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that could then fuel the actual reproduction
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So in some ways, people think that RNA gives you, you know,
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the most bang for your buck in a single molecule.
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And therefore, you know, it gives you all the features
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that you might think are life.
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And so this is sort of where this RNA world conjecture
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came from is because of those two properties.
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Isn't it amazing that RNA came to be in general?
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Isn't it? Yes, that is amazing.
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Okay, so we're not talking down about RNA.
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No, no, I love RNA.
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It's one of my favorite molecules.
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I think it's beautiful.
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It's just not step one.
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Yeah, I think the issue,
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it's not even the RNA world is a problem.
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And actually, if you really dig into it,
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the RNA world is not one hypothesis.
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It is a set of hypothesis, hypothesis, sorry.
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And they range from a molecule of RNA
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spontaneously emerged on the early earth
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and started evolving,
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which is kind of like the hardest RNA world scenario,
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which is the one I cited.
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And I get a little animated about
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because it seems so blatantly wrong to me,
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but that's a separate story.
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And then the other one is actually something I agree with,
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which is that you can say there was an RNA world
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because RNA was the first genetic material
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for life on earth.
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So an RNA world could just be the earliest organisms
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that had genetics in a modern sense
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didn't have DNA evolved yet, they had RNA, right?
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And so that's sort of a softer RNA world scenario
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in the sense that it doesn't mean
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it was the first thing that happened,
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but it was a thing that definitely was part
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of the lineage of events that led to us.
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So if life was like a best of album,
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it would be on the,
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it'd be one of the songs on there.
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Yes. One of the early songs.
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It's on the greatest hits.
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Greatest hits, that's the word I was looking for.
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Okay, did life, do you think originate once,
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twice, three times on earth, multiple times?
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What do you think?
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I think that's a really difficult question.
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Is it an important question?
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It's a super important question.
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No, that's, no, it's a really important question.
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And so there's some, so there's,
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there's a lot of questions in that question.
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So one of the first ones that I think needs to be addressed
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is is the original life a continuous process
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So we think about the original life as something
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that happened on earth, say almost four billion years ago
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because we have evidence of life emerging very early
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And then an original life event, quote unquote,
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a singular event, whatever that was happened.
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And then all life on earth that we know
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is a descendant of that particular event
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in our universe, right?
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And so, but we don't have any idea one way or the other
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if the original life is happening repeatedly
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and maybe it's just not taking off
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because life is already established.
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That's an argument that people will make
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or maybe there are alternative forms of life on earth
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that we don't even recognize.
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So this is the idea of a shadow biosphere
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that there actually might just be completely
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other life on earth, but it's so alien
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that we don't even know what it is.
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I'm gonna have to talk to you about the shadow biosphere.
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Yeah, that's a fun one.
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In a second, but first let me ask
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for the other alternative, which is panspermia.
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So that's the idea, the hypothesis that life exists
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elsewhere in the universe and got to us
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and we're like an asteroid or a planetoid
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or some according to Wikipedia space dust,
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whatever the heck that is, it sounds fun.
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But basically it wrote along whatever kind of rock
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Do you think that's at all a possibility?
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So I think the reason that most original life scientists
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are interested in the original life on earth
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and say not the original life on Mars
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and then panspermia, the exchange of life between planets
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being the explanation is once you start removing
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the original life from earth, you know,
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even less about it than you do if you study it on earth.
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Although I think there are ways of reformulating the problem.
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This is why I said earlier, like,
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oh, you mean the historical original life problem.
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You don't mean the problem of how does life arise
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in the universe and what the universal principles are
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because there's this historic problem.
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How did it happen on early earth?
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And there's a more tractable general problem
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of how does it happen and how does it happen
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is something we can actually ask in the lab.
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How did it happen on early earth
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is a much more detailed and nuanced question
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and requires detailed knowledge of what was happening
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on early earth that we don't have.
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And I'm personally more interested in general mechanisms.
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So to me, it doesn't matter if it happened on earth
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or it happened on Mars.
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It just matters that it happened.
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We have evidence that happened.
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The question is, did it happen more than once
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And so the reason I don't find Panspermia as a particularly,
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I think it's a fascinating hypothesis.
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I definitely think it's possible.
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And I in particular think it's possible
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once you get to the stage of a life
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where you have technology
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because then you obviously can spread out into the cosmos.
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But it's also possible for microbes
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because we know that certain microorganisms
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can survive the journey in space
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and they can live in a rock and go between Mars and earth.
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Like people have done experiments
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to try to prove that could work.
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So in that scenario, it's super cool
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because then you get planetary exchange.
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But say we go find, we go look for life on Mars
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and it ends up being exactly the same life
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we have on earth biochemically speaking.
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Then we haven't really discovered something new
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about the universe.
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What kind of aliens are possible?
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Were there other original life events?
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If we find, if all the life we ever find
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is the same original life event in the universe,
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it doesn't help me solve my problem.
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But it's possible that that would be a sign
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that you could separate the environment
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from the basic ingredients.
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So you can have like a life gun
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that you shoot throughout the universe.
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And then like once you shoot it,
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I think the Simpsons were the make up gun.
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That was a great episode.
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When you shoot this life gun, it'll find the earths.
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It'll like get sticky, it'll stick to the earths.
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And that kind of reduces the barrier of like the time
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it takes, the luck it takes to actually from nothing,
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from the basic chemistry, from the basic physics
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in the universe for the life to spring up.
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Yeah, I think this is actually super important.
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Just think about like does life getting seeded on a planet
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have to be geochemically compatible with that planet?
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So you're suggesting like we could just shoot guns in space
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and like life could go to Mars
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and then it would just live there and be happy there.
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But that's actually an open question.
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So one of the things I was gonna say in response
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to your question about whether the original life
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happened once or multiple times
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is for me personally right now,
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am I thinking all this changes on a weekly basis?
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But is that I think of life more as a planetary phenomena.
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So I think the original life because life is so
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intimately tied to planetary cycles and planetary processes.
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And this goes all the way back
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through the history of our planet,
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that the original life itself grew out of geochemistry
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and became coupled and controlled geochemistry.
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And when we start to talk about life existing on the planet
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is when we have evidence of life
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actually influencing properties of the planet.
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And so if life is a planetary property,
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then going to Mars is not a trivial thing
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because you basically have to make Mars more Earth like.
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And so in some sense, like when I think about
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sort of longterm vision of humans in space, for example,
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really what you're talking about when you're saying,
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let's send our civilization to Mars is you're not saying,
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let's send our civilization to Mars.
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You're saying, let's reproduce our planet on Mars.
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Like the information from our planet actually has to go to Mars
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and make Mars more Earth like,
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which means that you're now having a reproduction process
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like a cell reproduces itself to propagate information
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Planets have to figure out how to reproduce their conditions
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including geochemical conditions on other planets
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in order to actually reproduce life in the universe.
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Which is kind of a little bit radical,
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but I think for longterm sustainability of life
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on the planet, that's absolutely essential.
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So if we were to think about life as a planetary phenomena,
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and so life on Mars would be best
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if it's way different than life on Earth,
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we have to ask the very basic question of what is life?
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I actually don't think that's the right question to ask.
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It took me a long time to get there, right?
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Yeah, you cross it off your list, it's wrong.
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I mean, I think it has an answer,
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but I think the part of the problem is,
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most of the places in science where we get really stuck
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is because we don't know what questions to ask.
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And so you can't answer a question
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if you're asking the wrong question.
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And I think the way I think about it is,
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obviously I'm interested in what life is.
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So I'm being a little cheeky when I say,
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that's the wrong question to ask.
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That's exactly like the question
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that's like the core of my existence.
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But I think the way of framing that is,
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what is it about our universe that allows features
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that we associate life to be there?
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And so really, I guess when I'm asking that question,
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what I'm after is an explanatory framework
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for what life is, right?
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And so most people, they try to go in and define life
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and they say, well, life is, say,
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a self reproducing chemical system
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capable of Darwinian evolution.
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That's a very popular definition for life.
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Or life is something that metabolizes and eats.
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That is not how I think about life.
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What I think about life is there are principles
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and laws that govern our universe
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that we don't understand yet
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that have something to do with
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how information interacts with the physical world.
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I don't know exactly what I mean, even when I say that
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because we don't know these rules.
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But it's a little bit like, I like to use analogies.
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You give me time to be like a little long winded
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for a second, even in essay.
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But if you look at the history of physics, for example,
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this is like, so we are in the period of the development
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of thought on our planet
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where we don't understand what we are yet, right?
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There was a period of thought in the history of our planet
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where we didn't understand what gravity was.
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And we didn't understand, for example,
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that the planets in the heavens were actually planets
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or that they operated by the same laws that we did.
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And so there has been this sort of progression
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of getting a deeper understanding
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of explaining basic phenomena like,
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I'm not gonna drop the cup, I'll drop the water bottle.
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Okay, that fell, right?
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But why did that fall?
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This is why I'm a theorist, not an experiment specialist.
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I could have gone wrong in so many ways.
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I know, I could have, especially if I did the cup
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Anyway, so if you take this view
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that there's sort of some missing principles,
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I associate them to information.
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And what the sort of feeling there is,
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there's some missing explanatory framework
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for how our universe works.
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And if we understood that physics,
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it would explain what we are.
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It might also explain a lot of other features
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we don't associate to life.
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And so it's a little like,
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people accept the fact that gravity
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is a universal phenomena.
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But when we wanna study gravity,
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we study things like large scale galactic structures
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or black holes or planets.
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If we wanna understand information
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and how it operates in the physical world,
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we study intelligent systems or living systems
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because they are the manifestation of that physics.
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And the fact that we can't see that clearly yet
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or we don't have that explanatory framework,
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I think it's just because we haven't been thinking
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about the problem deeply enough.
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But I feel like if you're explaining something,
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you're deriving it from some more fundamental property.
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And of course, I have to say I'm wearing my physicist hat.
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So I have a huge bias of liking simple elegant explanations
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of the universe that really are compelling.
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But I think one of the things that I've sort of maybe
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in some ways rejected my training as a physicist
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is that most of the elegant explanations
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that we have so far don't include us in the universe.
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And I can't help but think there's something really special
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about what we are and there have to be some deep principles
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And so that's sort of my perspective on it.
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Now, when you ask me what life is,
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I have some ideas of what I think it is.
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But I think that we haven't gotten there yet
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because we haven't been able to see that structure.
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And just to go back to the gravity example,
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it's a little like in ancient times they didn't know,
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I was talking about stars and heavens and things,
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they didn't know those were governed
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by the same principles as that started experiment.
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Here's where I was going with it.
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Once you realize like Newton did that,
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heavenly motions and earthly motions
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are governed by the same principles
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and you unify terrestrial and celestial motion,
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you get these more powerful ideas.
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And I think where life is,
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is somehow unifying these abstract ideas
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of computation and information with the physical world,
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with matter and realizing that there's some
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explanatory framework that's not physics
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and it's not computation, but it's something that's deeper.
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So answering the question of what is life
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requires deeply understanding something about the universe
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as information processing, the universe's computation.
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Something about, like would,
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once you come up with an answer to what is life,
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will the words information and computation
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be in the paragraph?
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No, I don't think so.
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Oh, damn it, okay.
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I know, it doesn't help, does it?
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I know, I hate, actually I hate this about what I do
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because it's so hard to communicate, right?
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With words, like when you have words
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that are ideas that have historically described one thing
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and you're trying to describe something
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that people haven't seen yet and the words just don't fit.
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Is it too ambiguous, the word information?
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We could switch to binary if you want.
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Yeah, no, I don't think it's binary either.
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I think information is just loaded.
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I use it, so the other way I might talk about it
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is the physics of causation, but I think that's worse
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because causation is even more loaded word
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So causation is fundamental, you think?
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And in some sense, I think the physics,
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so this is the really radical part,
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in some sense, like when I really think about it
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sort of most deeply, what I think life is
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is actually the physics of existence,
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what gets to exist and why.
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And for simple elementary particles,
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that's not very complicated
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because the interactions are simple,
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but for things like you and me and human civilizations,
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what comes next in the universe
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is really dependent on what came before.
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And there's a huge space of possibilities
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of things that can exist.
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And when I say information and causation,
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what I mean is why is it that cups evolved in the universe
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and not some other object that could deliver water
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I don't know what you would call it.
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Maybe it wouldn't be a cup, but it's a huge,
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it's, people talk about the space of things
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that could exist as being actually infinitely large, right?
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I don't know if I believe in infinity,
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but I do think that there is something very interesting
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about the problem of what exists in its relationship to life.
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So do you think the set of things
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that could exist as finite is very large?
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But like if we were to think about the physics of existence,
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like how many shapes of mugs can there be?
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Like it is an initial programming.
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I should go to the math department for that.
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So that's not a topology question.
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I just mean maybe another way to ask is,
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what do you think is fundamental to the universe
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and what is emergent?
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So if existence, are we supposed to think of that
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as somehow fundamental, you think?
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So there's a couple of problems in physics
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that I think this is related to.
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One is why does mathematics work at describing reality so well?
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And then there is this problem of we don't understand
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why the laws of physics are the way they are
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or why certain things get to exist
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or what put in place the initial condition of our universe,
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There's all of these sort of really deep and big problems
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and they all indirectly are related,
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I think to the same kind of thing that,
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our physics is really good if you specify
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the initial condition at specifying
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a certain sequence of events,
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but it doesn't deal with the fact
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that other things could have happened,
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which is kind of an informational property
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like a counterfactual property.
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And it's not good at explaining,
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you know, this conversation right now,
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it's just, there are certain things
link |
that are outside the explanatory reach of current physics
link |
and I think they require looking at it
link |
from a completely different direction.
link |
And so I don't wanna have to fine tune
link |
the initial condition of the universe
link |
to specify precisely all the information
link |
in this conversation.
link |
I think that's a ridiculous assertion,
link |
but that's sort of like how people wanna frame it
link |
when they're talking about, you know,
link |
the standard model is sufficient
link |
if we had computing power to basically explain
link |
all of life in our existence.
link |
An interesting thing you said is,
link |
the way we think about information and computation
link |
is by observing a particular kind of systems on Earth
link |
that exhibit something we think of as intelligence,
link |
but that's like looking at, I guess,
link |
the tip of an iceberg and we should be really looking
link |
at the fundamentals of like the iceberg,
link |
like what makes water and ice
link |
and the chemistry from which intelligence
link |
emerges essentially.
link |
We can't just couple the information from the physics
link |
and I think that's what we've gotten really good at doing,
link |
especially with sort of the modern age
link |
where, you know, software is so abstracted from hardware.
link |
But the entire process of biological evolution
link |
has basically been built,
link |
like been building layers of increasing abstraction.
link |
And so it's really hard to see that physics in us,
link |
but it's much clearer to see it in molecules.
link |
Yeah, but I guess I'm trying to figure out
link |
what do you think are the best tools to look at it?
link |
What do you think?
link |
What's the physics of an open mind?
link |
I think if we solve that, we'll solve everything.
link |
I'm saying an open mind
link |
because I think the biggest stumbling block
link |
to understand sort of the things
link |
I've been trying to articulate
link |
or and when I talk also with colleagues
link |
that are thinking deeply about these same issues
link |
is none of it is inconsistent with what we know.
link |
It's just such a radically different perception
link |
of the way we understand things now
link |
that it's hard for people to get there.
link |
And in some ways you have to almost forget what you've learned
link |
in order to learn something new, right?
link |
So I feel like most of my career
link |
trying to understand the problem of life
link |
has been variously forgetting
link |
and then relearning things that I learned in physics
link |
and I think you have to have a capacity to learn things
link |
but then accept that things that you learned
link |
or might need refinement or reframing.
link |
And the best way I can say that
link |
is just like with a physics education
link |
there are just certain things you're told in undergrad
link |
that are like facts about the world.
link |
And your physics professors never tell you
link |
that those facts actually emerge from a human mind, right?
link |
So we're taught to think about say the laws of physics
link |
for example, as this like autonomous thing
link |
that exists outside of our universe
link |
and tells our universe how it works.
link |
But the laws of physics were invented by human minds
link |
to describe things that are regularities
link |
in our everyday experience.
link |
They don't exist autonomous to the universe.
link |
Right, so it's like turtles on top of turtles
link |
but eventually gets to the human mind
link |
and then you have to explain the human mind with the turtles.
link |
So you have to, it comes from humans,
link |
this understanding, this simplification of the universe,
link |
There's a guy named Stephen Wolf from,
link |
there's a concept called cellular automata.
link |
So there's some mysteries in these systems
link |
that are computational in nature
link |
that have maybe echoes of the kind of mysteries
link |
we should need to solve to understand what is life.
link |
So if we could talk, take a computational view of things,
link |
do you think there's something compelling
link |
to reducing everything down to computation
link |
like the universe's computation
link |
and then trying to understand life.
link |
So throw away the biology, throw away the chemistry,
link |
throw away even the physics
link |
that you learn undergrad and graduate school
link |
and a more look at these simple little systems
link |
whether it's cellular automata or whatever
link |
the heck kind of computational systems
link |
that operate on simple local rules
link |
and then create complexity as they evolve.
link |
Is it at all, do you think productive
link |
to focus on those kinds of systems
link |
to get an inkling of what is life?
link |
And if it is, do you think it's possible
link |
to come up with some kind of laws and principles
link |
about what makes life in those computational systems?
link |
So I like cellular automata.
link |
I think they're good toy models,
link |
but mostly like where I've thought about them
link |
and use them is to actually,
link |
let's say poke at sort of the current conceptual framework
link |
that we have and see where the flaws are.
link |
So I think like the part that you're talking about
link |
that people find intriguing is that
link |
if you have like a fairly simple rule
link |
and you specify some initial condition
link |
and you run that rule on that initial condition
link |
you could get really complex patterns emerging.
link |
And ooh, doesn't that look life like?
link |
Well, it's like really surprising.
link |
It is really surprising and they're beautiful.
link |
And I think they have a lot of nice features
link |
associated to them.
link |
I think the things that I find, yeah.
link |
So I do think as a proof of principle
link |
that you can get complex things emerging
link |
from simple rules, they're great.
link |
As a sort of proof of principle
link |
about some of the ways that we might think of computation
link |
as being sort of a fundamental principle
link |
for dynamical systems
link |
and maybe the evolution of the universe as a whole,
link |
they're a great model system.
link |
As an explanatory framework for life,
link |
I think they're a bit problematic
link |
for the same reason that the laws of physics
link |
are a bit problematic.
link |
And the clearest way I can articulate that is
link |
like cellular automata are actually cast
link |
in sort of a conceptual framework
link |
for how the universe should be described
link |
that goes all the way back to Newton, in fact,
link |
with this idea that we can have a fixed law of motion
link |
which exists sort of, it's given to you.
link |
You know, the great programmer in the sky
link |
gave you this equation or this rule
link |
and then you just run with it.
link |
And the rule doesn't have, so a good feature of the rule
link |
is it doesn't have specified in the rule
link |
information about the patterns it generates.
link |
So you wouldn't want, for example,
link |
the my cup or my water bottle or me sitting here
link |
to be specified in the laws of physics,
link |
that would be ridiculous
link |
because it wouldn't be a very simple explanation
link |
of all the things happening,
link |
it'd have to explain everything.
link |
So cellular automata have that feature
link |
and the laws of physics have that feature.
link |
But, you know, you also need to specify the initial condition.
link |
And it also, it basically means that everything
link |
that happens is sort of a consequence
link |
of that initial condition.
link |
And I think this kind of framework
link |
is just not the right one for biology.
link |
And part of the way that it's easiest to see this
link |
is a lot of people talk about self reference
link |
being important in life.
link |
The fact that, you know, like the genome
link |
has information encoded in it,
link |
that information gets read out.
link |
It specifies something about the architecture of a cell.
link |
The architecture of the cell includes the genome.
link |
So the genome has basically self referential information.
link |
Self reference obviously comes up in computational law
link |
because it's kind of foundational to Turing's work
link |
and what Girtle did with the incompleteness theorems
link |
So there's a lot of parallels there
link |
and people have talked about that at depth.
link |
But the other way of kind of thinking about it
link |
in terms of like a more physicsy way of talking about it
link |
is that what it looks like in biology
link |
is that the rules or the laws depend on the state.
link |
This is typical in computer science.
link |
This is obvious to you.
link |
The update rule depends on the state of the machine.
link |
But you don't think about that being sort
link |
of the dynamic in physics.
link |
The rule is given to you and then it's
link |
a very special subclass, say, of computations
link |
if you don't ever change the update.
link |
But in biology, it seems to be that the state and the law
link |
change together as a function of time.
link |
And we don't have that as a paradigm in physics.
link |
And so a lot of people talk about this
link |
as being kind of a perplexing feature
link |
that maybe there are certain scenarios where the laws of physics
link |
or the laws that govern a particular system
link |
actually change as a function of the state of that system.
link |
So yeah, the hope of physics, it's a hope, I guess,
link |
but often stated as an underlying assumption
link |
is that the law is static.
link |
And even having laws that vary in time,
link |
not even as a function of the state, is very radical when you.
link |
The time in general.
link |
Like, you want to remove time from the equation
link |
as much as possible.
link |
There's some interesting things in this,
link |
like when we think more deeply about the actual physics
link |
that we're trying to propose governs life with me
link |
with collaborators and then also other people that
link |
think about similar things, that time might actually
link |
be fundamental and there really is an ordering to time.
link |
And that events in the universe are unique
link |
because they have a particular, you know,
link |
they happen like an object in the universe
link |
requires a certain history of events in order to exist,
link |
which therefore suggests that time really
link |
does have an ordering.
link |
I'm not talking about the flow of time
link |
and our perception of time, just the ordering of events.
link |
The causation of things.
link |
There's that word again.
link |
So causation, when you say time, you mean causation.
link |
In your proposed model of the physics of life,
link |
the fundamental thing would be causation.
link |
If you were to bet your money on one particular horse
link |
And then space is emergent.
link |
So everything is emergent except time.
link |
Kind of, yeah, or causation.
link |
And laws change all the time.
link |
Why does it look like laws are the same?
link |
Well, because, well, one way, and I actually,
link |
this idea comes from Lee Cronin because I work with him
link |
very closely on these things, is that the laws of physics
link |
look the way they do because they're low memory laws.
link |
So they don't require a lot of information to specify them.
link |
They're very easy for the universe to implement.
link |
But if you get something like me, for example,
link |
I require a 4 billion year history to exist in the universe.
link |
I come with a lot of historical baggage.
link |
And that's part of what I am as a set of causes
link |
that exist in the universe.
link |
So I have local rules that apply to me
link |
that are associated with the information in my history
link |
that aren't universal to every object in the universe.
link |
And there are some things that are very easy to implement,
link |
low memory rules that apply to everything in the universe.
link |
So there's no shortcuts to you.
link |
So yeah, I don't believe in things like Boltzmann Brains
link |
or fluctuations out of the vacuum that can produce things
link |
like your desk ornaments.
link |
I actually think they require a particular causal chain
link |
of events to exist.
link |
Well, I appreciate the togetherness of that.
link |
So how does that, if we have to simulate the entire universe
link |
to create the ornaments and the two of us,
link |
how are we supposed to create engineer life in a lab?
link |
This goes back to the critique of the RNA world.
link |
I think one of the problems, and I'll
link |
get to answer your question, but I think this
link |
is kind of relevant here, one of the problems of the RNA
link |
world when we test it in the laboratory
link |
is how much information we're putting into the experiment.
link |
We specify the flasks, we make pure reagents, we mix them,
link |
we take them out, we put them in the next flask,
link |
we change the pH, we change the UV light,
link |
and then we get a molecule.
link |
And it's not even an RNA molecule necessarily,
link |
it might just be a base.
link |
And so people don't usually think about the fact
link |
that we're agents in the universe making that experiment,
link |
and therefore we put a little bit of life into that experiment,
link |
because it's part of our biological lineage
link |
in the same sense that I am a part of the biological lineage.
link |
Our ideas are injecting life to the experiment.
link |
And the constraints that we put on the experiments,
link |
because those conditions wouldn't exist in the universe
link |
on planet Earth at that time without us
link |
as the boundary condition, right?
link |
Even though we're not actually adding any actual like
link |
chemistry or biology that could be identified as life,
link |
the constraints we're adding to the experiment,
link |
the design of the experiment.
link |
Yeah, you can think of the design experiment as a program.
link |
You put information in.
link |
It's an algorithmic procedure
link |
that you design the experiment.
link |
And so the origin life problem becomes one
link |
of minimizing the information we put into physics
link |
to actually watch the spontaneous origin of life.
link |
Can we have, so is it possible in the lab
link |
to have an information vacuum then?
link |
If we could, we would, that would be amazing.
link |
That's a good question for Lee.
link |
Yeah, you guys, by the way,
link |
for people who don't know Lee Cronin,
link |
is you guys are colleagues.
link |
And I've gotten the chance to listen
link |
to the two of you talking.
link |
There's great chemistry
link |
and your brilliant brainstorming together.
link |
And there's a really exciting community here
link |
of brilliant people from different disciplines
link |
working on the problem of life, of complexity,
link |
of, I don't know, whatever.
link |
The words fail us to describe the exact problem
link |
we're trying to actually understand here.
link |
Intelligence, all those kinds of things.
link |
Okay, so what, from a lab perspective.
link |
So Lee, I guess, would you call him a chemist?
link |
I think by training, he's a chemist.
link |
But I think most of the people that work in the field,
link |
we do have lost their discipline.
link |
That's why I couldn't answer your question earlier.
link |
I don't know what you call him.
link |
I don't know what I call myself.
link |
I don't know what I call any of my friends.
link |
So why is it so hard to create,
link |
and it's an interesting question
link |
to create biological life in the lab.
link |
Like from your perspective,
link |
is that an important problem to work on
link |
to try to recreate the historical origin of life on earth
link |
or echoes of the historical origin?
link |
I think echoes is more appropriate.
link |
I don't think asking the question
link |
of what was the exact historical sequence of events
link |
and engineering every step in the process
link |
to make exactly the chemistry of life on earth
link |
as we know it is a meaningful way of asking the question.
link |
And it's a little bit like,
link |
since you're in computer science,
link |
like if you know the answer to a problem,
link |
it's easier to find a program to specify the output, right?
link |
But if you don't know the answer a priori,
link |
finding an algorithm for like say,
link |
finding a prime or something,
link |
it's easy to verify it's a prime number.
link |
It's hard to find the next prime.
link |
And the way the original life is structured right now
link |
and the historical problem is you know the answer
link |
and you're trying to retroject it
link |
by breaking it down into the set of procedures
link |
where you're putting a lot of information in.
link |
And what we need to do is ask the question of,
link |
how is it that the rules of how our universe is structured
link |
permit things like life to exist
link |
and what is the phenomena of life?
link |
And those questions are obviously essentially
link |
the same question.
link |
And so you're looking essentially
link |
for this missing physics,
link |
this missing explanation for what we are.
link |
And you need to set up proper experiments
link |
that are gonna allow you to probe
link |
the vast complexity of chemistry
link |
in an unconstrained way with as little information
link |
put in as possible to see when things,
link |
when does information actually emerge?
link |
How does it emerge?
link |
And part of the sort of conjecture we have is
link |
that this physics only becomes relevant
link |
or at least this is my personal conjecture
link |
and it's sort of validated by this kind of theory experiment
link |
collaboration that we have working in this area.
link |
That this sort of, I mean,
link |
I made the point about like gravity existing everywhere, right?
link |
But when you study an atomic nucleus,
link |
you don't care about gravity,
link |
it's not relevant physics there, right?
link |
It's weak, it doesn't matter.
link |
And so this idea that there's kind of a physics
link |
associated with information,
link |
for me, it's very evident that that physics
link |
doesn't become relevant until you need information
link |
to specify the existence of a particular object.
link |
And the scale of reality where that happens
link |
is in chemistry because of the combinatorial diversity
link |
of chemical objects that can exist far out exceeds
link |
the amount of resources in our universe.
link |
So if you want it, you can't make every possible protein
link |
of lengths, 200 amino acids is not enough resources.
link |
So in order to, for this particular protein to exist
link |
and this protein to exist in high abundance
link |
means that you have to have a system that has knowledge
link |
of the existence of that protein and can build it.
link |
So existence comes to be at the chemical level.
link |
So existence is most, is best understood
link |
at the chemical level.
link |
It's most evident.
link |
It's a little bit like nobody argues
link |
that gravity doesn't exist in atomic nucleus.
link |
It's just not relevant physics there, right?
link |
So the physics of information is everywhere.
link |
It exists at every combinatorial scale,
link |
but it becomes more and more relevant
link |
the more set of possibilities that could exist
link |
because you're, you have to specify more and more
link |
about why this thing exists and not the infinite.
link |
It's not an infinite set, but you know,
link |
the set of undefined set of other things that could exist.
link |
So can I ask a weird question, which is,
link |
so let's look into the future.
link |
I try that every day, it never works.
link |
So say a Nobel Prize is given in physics,
link |
maybe chemistry, for discovering the origin of life.
link |
No, but not the historical origin.
link |
Some kind of thing that we're talking about.
link |
What exactly would, what do you think that like,
link |
what do you think that person maybe you did
link |
to get that Nobel Prize?
link |
Like what would they have to have done?
link |
Cause you could do a bunch of experiments
link |
that go like within the aha moment.
link |
Like you rarely get the Nobel Prize
link |
for like you've solved everything, we're done.
link |
It's like some inkling of some deep truth.
link |
Like what do you think that would actually look like?
link |
Would it be an experimental result?
link |
I mean, it will have to have some kind of experimental
link |
maybe validation component.
link |
So what would that look like?
link |
This is an excellent question.
link |
I wanna, sorry, I'm gonna make a quick point,
link |
which is just a slight tangent,
link |
but like when people ask about the origin of mass
link |
and like looking for the Higgs mechanism and things,
link |
they never are like,
link |
we need to find the historical origins of life
link |
in the early, although those things are related, right?
link |
So this problem of origins of life in the lab,
link |
I think is really important,
link |
but the Higgs is a good example
link |
because you had theory to guide it.
link |
So somehow you need to have an explanatory framework
link |
that can say that we should be looking for these features
link |
and explain why they might be there
link |
and then be able to do the experiment
link |
and demonstrate that it matches with the theory,
link |
but it has to be something that is outside
link |
sort of the paradigm of what we might expect
link |
based on what we know, right?
link |
So this is a really sort of tall order.
link |
And I think, I mean,
link |
I guess the way people would think about it is like,
link |
if you had a bacteria that climbed out of your test tube
link |
or something and it was like,
link |
moving around on the surface,
link |
that would be ultimate validation.
link |
You saw the original life in an experiment,
link |
but I don't think that's quite what we're looking for.
link |
I think what we're looking for is evidence
link |
of when information that originated
link |
within the balance of your experiment
link |
and you can demonstratably prove a merge spontaneously
link |
in your experiment wasn't put in by you,
link |
actually started to govern the future dynamics
link |
of that system and specify it.
link |
And you could somehow relate those two features directly.
link |
So you know that the program specifying
link |
what's happening in that system
link |
is actually internal to that system.
link |
Like say you have a chemical thing in a box.
link |
Well, so that's one Nobel Prize winning experiment,
link |
which is like information in some fundamental way
link |
originated within the constraints of the system
link |
without you injecting anything.
link |
But another experiment is you injected something.
link |
And got out information.
link |
So like you injected, I don't know,
link |
like some sugar and like something
link |
that doesn't necessarily feel like it should be information.
link |
Yeah, so I actually know,
link |
I mean, sugar is information, right?
link |
So part of the argument here
link |
is that every physical object is,
link |
well, it's information,
link |
but it's a set of causal histories
link |
and also a set of possible futures.
link |
So there is an experiment that I've talked a lot about
link |
with Lee Cronin, but also with Michael Lachman
link |
and Chris Kempis who are at Santa Fe
link |
about this idea that sometimes we talk about
link |
as like seeding assembly,
link |
which is you take a high complexity,
link |
like an object that exists in the universe
link |
because of a long causal history
link |
and you seed it into a system of lower causal history.
link |
And then suddenly you see all of this complexity
link |
So I think another validation of the physics
link |
would be, say you engineer an organism
link |
by purposefully introducing something
link |
where you understand the relationship
link |
between the causal history of the organism
link |
and the say very complex chemical set of ingredients
link |
you're adding to it.
link |
And then you can predict the future evolution
link |
of that system to some statistical set of constraints
link |
and possibilities for what it will look like in the future.
link |
You know, I'm a physical structure obviously,
link |
like I'm composed of atoms.
link |
The configuration of them
link |
and the fact that they happen to be me
link |
is because I'm not actually my atoms.
link |
I am a informational pattern
link |
that keeps repatterning those atoms into Sarah.
link |
And I have also associated to me like a space
link |
of possible things that could exist
link |
that I can help mediate come into existence
link |
because of the information in my history.
link |
And so when you understand sort of that
link |
time is a real thing embedded in a physical object,
link |
then it becomes possible to talk about
link |
how histories, when they interact,
link |
and history is not a unique thing.
link |
It's a set of possibilities.
link |
When they interact,
link |
how do they specify what's coming next?
link |
And then where does the novelty come from
link |
in that structure?
link |
Because some of it is kind of things
link |
that haven't existed in the past,
link |
can exist in the future.
link |
Let me ask about this entity that you call Sarah.
link |
I talk to myself about myself in third person sometimes.
link |
So maybe this is a good time to bring up consciousness.
link |
It's been here all along.
link |
So at least in this conversation,
link |
I think I've been conscious most of it,
link |
but maybe I haven't.
link |
Well, yes, so speak for yourself.
link |
You're projecting your consciousness onto me.
link |
You don't know if I'm conscious or not.
link |
Is that, he talked about the physics of existence.
link |
He talked about the emergence of causality,
link |
sorry, you talked about causality and time
link |
being fundamental to the universe.
link |
Where does consciousness fit into all of this?
link |
Like, do you draw any kind of inspiration
link |
or value with the idea of panpsychism
link |
that maybe one of the things that we ought to understand
link |
is the physics of consciousness?
link |
Like one of the missing pieces
link |
in the physics view of the world
link |
is understanding the physics of consciousness.
link |
Or like that word has so many concepts underneath it,
link |
but let's put consciousness as a label
link |
on a black box of mystery that we don't understand.
link |
Do you think that black box holds the key
link |
to finally answering the question of the physics of life?
link |
The problems are absolutely related.
link |
I think most, and I'm interested in both
link |
because I'm just interested in what we are.
link |
And to me, the most interesting feature
link |
of what we are is our minds
link |
and the way they interact with our minds.
link |
Like minds are the most beautiful thing
link |
that exists in the universe.
link |
So how do they come to be?
link |
Sorry to interrupt.
link |
So when you say we, you mean humans.
link |
I mean humans right now, but that's because I'm a human.
link |
Or at least I think I am.
link |
You think there's something special to this particular?
link |
No, no, no, no, no.
link |
No, I don't, I'm not a human centric thinker.
link |
But are you one entity?
link |
You said a bunch of stuff came together to make a Sarah.
link |
Like do you think of yourself as one entity?
link |
Or are you just a bunch of different components?
link |
Like is there any value to understand the physics of Sarah?
link |
Like, or are you just a bunch of different things
link |
that are like a nice little temporary side effect?
link |
Yeah, you could think of me as a bundle of information
link |
that just became temporarily aggregated
link |
into our individual.
link |
Yeah, that's fine.
link |
I agree with that view.
link |
I'll take that as a compliment actually.
link |
But you've, but nevertheless,
link |
that bundle of information has become conscious.
link |
At least keeps calling herself conscious.
link |
Yeah, I think I'm conscious right now,
link |
but I might not be, but that's okay.
link |
Or you wouldn't know.
link |
So yeah, so this is the problem.
link |
So yeah, usually people when they are talking
link |
about consciousness are worried
link |
about the subjective experience.
link |
And so I think that's why you're saying,
link |
I don't know if you're conscious
link |
because I don't know if you're experiencing
link |
this conversation right now.
link |
And nor do you know if I'm experiencing
link |
the conversation right now.
link |
And so this is why this is called
link |
the hard problem of consciousness
link |
because it seems impenetrable from the outside
link |
to know if something's having a conscious experience.
link |
And I really like the idea of also like
link |
the hard problem of matter,
link |
which is related to the hard problem of consciousness,
link |
which is you don't know the intrinsic properties
link |
of an electron not interacting,
link |
say for example, with anything else in the universe.
link |
All the properties of anything
link |
that exists in the universe are defined by its interaction
link |
because you have to interact with it
link |
in order to be able to observe it.
link |
So we can only actually know the things
link |
that are observable from the outside.
link |
And so this is one of the reasons
link |
that consciousness is hard for science
link |
because you're asking questions
link |
about something that's subjective
link |
and supposed to be intrinsic to what that thing is
link |
as it exists and how it feels about existing.
link |
And so I have thought a lot about this problem
link |
and its relationship to the problem of life.
link |
And the only thing I can come up with
link |
to try to make that problem scientifically tractable
link |
and also related to how I think about the physics of life
link |
is to ask the question,
link |
are there things that can only happen in the universe
link |
because there are physical systems
link |
that have subjective experience?
link |
So does subjective experience have different causes?
link |
That things that it can cause to occur
link |
that would happen in the absence of that?
link |
I don't know the answer to that question,
link |
but I think that's a meaningful way
link |
of asking the question of consciousness.
link |
I can't ask if you're having experience right now,
link |
but I can ask if you having experience right now
link |
changes something about you
link |
and the way you interact with the world.
link |
So does stuff happen?
link |
It's a good question to ask.
link |
Does stuff happen if consciousness is?
link |
Then it's a real physical thing, right?
link |
It has physical consequences.
link |
I'm a physicist, I'm biased.
link |
So I don't, you know, I can't get rid of that bias.
link |
It's really deeply ingrained.
link |
I've tried, but it's hard.
link |
But I mean, you're saying information is physical too.
link |
So like virtual reality and simulation,
link |
all the program is physical too.
link |
Yes, everything's physical.
link |
It's just not physical the way it's represented in our minds.
link |
So you, I love your Twitter.
link |
So you tweet these like deep thoughts and deep thoughts.
link |
That's what a theorist does when she's trying to experiment.
link |
It's like sitting there.
link |
I mean, I can just imagine you sitting there for like hours
link |
and all of a sudden just like this thought comes out
link |
and we get a little like inkling into the thought process.
link |
Yeah, usually it's like
link |
when I'm running between things and I'm talking about deep thoughts.
link |
Deep thoughts are hard to articulate.
link |
One of the things you tweet is ideologically,
link |
there are many parallels between the search
link |
for neural correlates of consciousness
link |
and for chemical correlates of life.
link |
How the neuroscience and astrobiology communities
link |
treat those correlates is entirely different.
link |
Can you elaborate against this kind of...
link |
The parallels, it has to do a little bit
link |
with the consciousness and the matter thing
link |
you're talking about.
link |
And I can't remember what state of mind I was
link |
when I was actually thinking about that,
link |
but I think part of it is...
link |
I bet you never thought you're gonna have
link |
to analyze your own tweets.
link |
It's an interesting historical juxtaposition of thinking.
link |
So the tweet is a historical...
link |
You're doing an assembly experiment right now
link |
because you're bringing a thought from the past
link |
into the present and trying to actually...
link |
Exactly, in the lab.
link |
This is experimental science right here
link |
on the podcast live.
link |
So go, let's see how the consciousness
link |
evolves on this one.
link |
Yeah, so in neuroscience, it's kind of accepted
link |
that we can't get at the subjective aspect of consciousness.
link |
So people are very interested in what would be
link |
a correlate of consciousness.
link |
What's a correlate?
link |
A correlate is a feature that relates to consciousness
link |
For example, a verbal report is a correlate of consciousness
link |
because I can tell you when I'm conscious.
link |
And then when I'm sleeping, for example,
link |
I can't tell you I'm conscious.
link |
So we have this assumption that you're not conscious
link |
when you're sleeping and you're conscious when you're awake.
link |
And so that's sort of like a very obvious example,
link |
but neuroscientists, which I'm no neuroscientist
link |
and I'm not an expert in this field.
link |
So they have very sophisticated ways of measuring activity
link |
in our brain and trying to relate that to verbal report
link |
and other proxies for whether someone is experiencing
link |
something and that's what is meant by neural correlates.
link |
And then so when people are trying to think about
link |
studying consciousness or developing theories
link |
for consciousness, they often are trying to build
link |
an experimental bridge to these neural correlates,
link |
recognizing the fact that a neural correlate
link |
may or may not correspond to consciousness
link |
because that problem's hard
link |
and there's all these associated issues to it.
link |
So that's from a neuroscience perspective,
link |
it's like fake it till you make it.
link |
Pretty much, yeah.
link |
You fake whatever the correlates are
link |
and hopefully that's going to summon
link |
the thing that is consciousness.
link |
Oh yeah, something like that.
link |
And so the same thing on the chemical correlates of life.
link |
That's an awesome concept.
link |
Is that something that people?
link |
No, I just made that up.
link |
That was original to that tweet.
link |
You can cite the tweet.
link |
Maybe I'll write it in a paper someday.
link |
Chemical correlates of life, that's a good title.
link |
I mean, first of all, your papers, too,
link |
that people should check out have great titles
link |
or papers you're involved with.
link |
So your tweets and titles are stellar
link |
and also your ideas,
link |
but the tweets and titles are much more important.
link |
Ideas will live longer.
link |
They're much more diffuse, though.
link |
Well, yeah, the tweet is the Trojan horse
link |
of the idea that sticks on for a long time.
link |
Okay, so is there anything to say
link |
about the chemical correlates of life?
link |
You're saying there are similar kind
link |
of ways of thinking about it,
link |
but you mentioned about the communities.
link |
Yeah, so I think in astrobiology,
link |
There's no concept of chemical correlates of life.
link |
We don't think about it that way.
link |
We think if we find molecules that are involved
link |
in biology, we've found life.
link |
So I think one of my motivations there
link |
was just to separate the fact
link |
that life has abstract properties associated to it.
link |
They become imprinted in material substrates
link |
and those substrates are correlates for that thing,
link |
but they are not necessarily the thing
link |
we're actually looking for.
link |
The thing that we're looking for is the physics
link |
that's organizing that system to begin with,
link |
not the particular molecules.
link |
In the same sense that your consciousness
link |
is not your brain, it's instantiated in your brain.
link |
It has to have a physical substrate,
link |
but the matter is not the thing that you're looking at.
link |
It's some other, at least not in the way
link |
that we have come to look at matter,
link |
with traditional physics and things.
link |
There's something else there
link |
and it might be this feature of history
link |
I was talking about,
link |
our time being actually physically represented there.
link |
Do you think consciousness can be engineered?
link |
In the same way that life can be.
link |
Wow, that was a fast answer.
link |
I didn't even think about that.
link |
That's interesting.
link |
You don't have a free will.
link |
No, I do have free will,
link |
but it's interesting,
link |
because I mean, you know.
link |
Oh, you're backtracking.
link |
And that was predestined.
link |
No, I do believe in free will,
link |
but I also think that there's kind of an interesting,
link |
you know, like what you're,
link |
speaking about consciousness,
link |
what are you consciously aware of
link |
versus like, what is your subconscious brain
link |
actually processing and doing?
link |
And sometimes there's conflict
link |
between your consciousness and your subconsciousness
link |
or your consciousness is a little slower
link |
than your subconscious.
link |
And intuition is a really important feature of that.
link |
And so a lot of the ways I do my science
link |
is guided by intuition.
link |
So when I give fast answers like that,
link |
I think it's usually
link |
because I haven't really thought about them
link |
and therefore that's probably telling me something.
link |
Let's continue the deep analysis of your tweets.
link |
You said that determinism in a tweet,
link |
determinism and randomness play important roles
link |
in understanding what life is.
link |
So let me ask on this topic of free will,
link |
what is determinism?
link |
What is randomness?
link |
And why the heck do they have anything to do
link |
with understanding life?
link |
And you threw free will in there.
link |
You just thrown all the stuff in the bag.
link |
Are they not related?
link |
I was being unfair.
link |
You didn't even capitalize a tweet, by the way.
link |
It was all lowercase.
link |
I must have been angry.
link |
Oh, that was, was that,
link |
can you analyze the emotion behind that?
link |
No, I actually, I.
link |
Just frustration or hope?
link |
So I already argued that I don't think
link |
that can happen without that whole causal history.
link |
And so I guess in some sense,
link |
the determinism for me arises
link |
because of the causal history.
link |
And I'm not really sure actually
link |
about whether the universe is random or deterministic.
link |
I just had this sort of intuition for a long time.
link |
I'm not sure if I agree with it anymore,
link |
but it's still kind of lingering.
link |
And I don't know what to do with this question.
link |
But it seems to me, you know,
link |
so there's, you asked the question, what is life?
link |
But you could also, why life?
link |
Why does life exist?
link |
What does the universe need life for?
link |
Not that the universe has needs,
link |
but you know, we have to anthropocentrize things sometimes
link |
to talk about them.
link |
And I had this feeling that if it was possible
link |
for a cup or a desk ornament or a phone on Mars
link |
to spontaneously fluctuate into existence,
link |
the universe didn't need life to create those objects.
link |
It wasn't necessary for their existence.
link |
It was just a random fluke event.
link |
And so somehow to me, it seems that it can't be
link |
that those things formed by random processes,
link |
they actually have to have a set of causes
link |
that accrue and form those things
link |
and they have to have that history.
link |
And so it seems to me that life was somehow deeply related
link |
to the question of whether the underlying rules
link |
of our universe had randomness in them
link |
or they were fully deterministic.
link |
And in some ways you can think about life
link |
as being the most deterministic part of physics
link |
because it's where the causes are precise in some sense.
link |
Or more stable, so like.
link |
Most stable, yes, most reliable.
link |
Most reliable for our, for how we, for the tools of physics.
link |
But what, where's the randomness come from then?
link |
Okay, so you were speaking with.
link |
I've gone in a tangent.
link |
So I'm not sure where we are in the, yeah.
link |
All of the universe is a kind of tangent.
link |
So we're embracing the tangent.
link |
You believe at this current time that you have free will.
link |
I believe my whole life I have free will.
link |
I still believe it.
link |
You still believe it.
link |
So at the same time, you think that
link |
in your conception of the universe,
link |
causality seems to be pretty fundamental.
link |
It kind of wants the universe to be deterministic.
link |
So how the heck do you think you have a free will
link |
and yet you value causality?
link |
Because I depart from the conception of physics
link |
that you can write down an initial condition
link |
and a fixed law of motion
link |
and that will describe everything.
link |
There's no incompatibility
link |
if you are willing to reject that assertion.
link |
So where's the randomness?
link |
Where's the magic that gives birth to the free will?
link |
Is it the randomness of the laws of physics?
link |
In my mind, what free will is,
link |
is the fact that I as a physical system
link |
have causal control over certain things.
link |
I don't have causal control over everything,
link |
but I have a certain set of things.
link |
And I'm also, as I described,
link |
sort of a nexus of a particular set of histories
link |
that exist in the universe
link |
and a particular set of futures that might exist.
link |
And those futures that might exist are in part specified
link |
by my physical configuration as me.
link |
And therefore, it may not be free will
link |
in the traditional sense.
link |
I don't even know what people mean
link |
when they're talking about free will.
link |
Honestly, it's like the whole discussion is really muddled.
link |
But in the sense that I am a causal agent,
link |
if you wanna call it that, that exists in the universe.
link |
And there are certain things that happen
link |
because I exist as me, then yes, I have free will.
link |
No, but do you, Sarah, have a choice
link |
about what's going to happen next?
link |
If the universe, could I have, if I run this?
link |
You have a choice.
link |
Where's the choice come from?
link |
I think that's related to the physics of consciousness.
link |
So one of the things I didn't say about that,
link |
and I don't know, maybe this is me just being hopeful
link |
because maybe I just wanna have free will,
link |
but I don't think that we can rule out the possibility
link |
because I don't think that we understand enough
link |
about any of these problems.
link |
But I think one of the things that's interesting for me
link |
about the sort of inversion of the question
link |
of consciousness that I proposed
link |
is one of the features that we do
link |
is we have imagination, right?
link |
And people don't think about imagination as a physical thing,
link |
but it is a physical thing.
link |
It exists in the universe, right?
link |
And so I'm like really intrigued by the fact
link |
that say humans for another physical system
link |
could do this too, it's not special to humans,
link |
but for centuries imagined flying machines and rockets.
link |
And then we finally built them, right?
link |
So they were represented in our minds
link |
and on the pages of things that we drew for hundreds of years
link |
before we could build those physical objects in the universe.
link |
But certainly the existence of rockets
link |
is in part causally caused by the fact
link |
that we could imagine them.
link |
And so there seems to be this property
link |
that some things don't exist.
link |
They've never physically existed in the universe,
link |
but we can imagine the possibility of them existing
link |
and then cause them to exist,
link |
maybe individually or collectively.
link |
And I think that property is related
link |
to what I would say about having choice or free will
link |
because that set of possibilities,
link |
that thing, those set of things that you can imagine
link |
is not constrained to your local physical environment
link |
And this is what's a little bit different
link |
about intelligence as we see it in humans
link |
and AI that we wanna build than biological intelligence
link |
because biological intelligence is predicated completely
link |
on the history of things that's seen in the past,
link |
but something happened with the neural architectures
link |
that evolved in multicellular organisms
link |
that they don't just have access to the past history
link |
of their particular set of events,
link |
but they can imagine things that haven't happened
link |
on their timeline.
link |
And as long as they're consistent with the laws of physics,
link |
So this is fascinating.
link |
It's trippy physics, but it exists.
link |
I mean, in some sense, if you look at like
link |
general relativity and gravity morphing space time,
link |
in that same way, maybe whatever the physics
link |
of consciousness might be, it might be morphing.
link |
That's like what free will is.
link |
It's morphing like the space,
link |
just like ideas make rockets come to life.
link |
It's somehow changing the space
link |
of possible realizations of like whatever.
link |
Life is kind of basically, if you wanna think about it,
link |
like life is sort of changing the probability distributions
link |
over what can exist.
link |
That's the physics of what life is.
link |
And then consciousness is this sort of layered property
link |
or imagination on top of it
link |
that kind of scrambles that a little bit more
link |
and like has access to...
link |
I don't know, it's kind of...
link |
We don't know how to describe it, right?
link |
Like that's why it's interesting, but...
link |
But it's probabilistic.
link |
So you do think like God plays dice.
link |
No, I think the description's probabilistic.
link |
I don't necessarily think the underlying physics
link |
I think the way that we can describe this physics
link |
is going to be probabilistic and statistical,
link |
but when we take measurements in the lab,
link |
but the underlying physics itself
link |
might still be deterministic.
link |
I don't know, maybe I'm...
link |
It's hard to know what concepts to hold on to.
link |
So I find myself constantly rejecting concepts,
link |
but then I have to grab another one
link |
and try to hold on to something from intellectual history.
link |
Well, it's possible that our mind
link |
is not able to hold the correct concepts in mind at all.
link |
Like we're not able to even conceive of them correctly.
link |
Maybe the words deterministic or random
link |
are not the right, even words conscious to be holding.
link |
But maybe you can talk to the theory of everything,
link |
this attempt in the current set of physical laws
link |
to try to unify them.
link |
Is there any hope that once a theory of everything
link |
is developed, and by theory of everything,
link |
I mean in a narrow sense of unifying quantum field theory
link |
and general relativity,
link |
do you think that will contain some...
link |
Like in order to do that unification,
link |
you would have to get something
link |
that would then give hints about the physics of life,
link |
physics of existence, physics of consciousness.
link |
Yeah, I used to not,
link |
but I actually, I have become increasingly convinced
link |
that it probably will.
link |
And part of the reason is,
link |
I think I've talked a little bit already
link |
about these holes in physics,
link |
like the theories we have in physics,
link |
they have problems, they have lots of problems,
link |
and they're very deep problems,
link |
and we don't know how to patch them.
link |
And some of those problems become very evident
link |
when you try to patch quantum mechanics
link |
and general relativity together.
link |
So there is this kind of interesting feature
link |
that some of the ways of patching that
link |
might actually closely resemble the physics of life.
link |
And so the place where that actually comes up most,
link |
and actually we just had a workshop
link |
in the Beyond Center where I work at Arizona State University,
link |
and Lee Smolin made this point that he thinks
link |
that the theory of quantum gravity,
link |
when we solve it, is gonna be the same theory
link |
that gives rise to life.
link |
And I think that I agree with him on some levels
link |
because there's something very interesting
link |
where if you look at these sort of causal set theories
link |
of gravity, where they're looking for space
link |
as being emergent, and so space time is an emergent concept
link |
from a causal set, which is also sort of related,
link |
I think, to what Wolfram's doing with his physics project,
link |
it's the same kind of underlying math
link |
that we have in this theory
link |
that we've been developing related to life
link |
called assembly theory, which is basically trying
link |
to look at complex objects like molecules
link |
and bacteria and living things as basically being assembled
link |
from a set of component parts,
link |
and that they actually encode all the possible histories
link |
that they could have in that physical object.
link |
So mathematically, all these ideas, I think, are related.
link |
I think a lot of people are thinking about this
link |
from different perspectives, and then constructor theory
link |
that David Deutch and Karen Merledo have been developing
link |
is a totally different angle on it,
link |
but I think getting at some similar ideas,
link |
so it's a really interesting time right now, I think,
link |
for the frontiers of physics and how it's relating
link |
to maybe deeper principles about what life is.
link |
So short answer, yes, long winded answer, rewind.
link |
Can we talk about aliens?
link |
So one, I think one interesting way to sneak up
link |
on the question of what is life is to ask,
link |
what should we look for in alien life?
link |
You know, if we were to look out into our galaxy
link |
and into the universe and come up with a framework
link |
of how to detect alien life, what should we be looking for?
link |
Is there like set of rules, like it's both the tools
link |
and the tools that serve the senses
link |
for certain kind of properties of life.
link |
So what should we look for in alien life?
link |
Yeah, so we have a paper actually coming out on Monday,
link |
which is collaboration.
link |
It's actually really Lee Cronin's lab,
link |
but my group worked with him on it
link |
and we're working on the theory,
link |
which is this idea that we should look for life
link |
as high assembly objects.
link |
What we mean by that is,
link |
which is actually observationally measurable.
link |
And this is one of the reasons
link |
that I started working with Lee on these ideas
link |
is because being a theorist, it's easy to work in a vacuum.
link |
It's very hard to connect abstract ideas
link |
about the nature of life
link |
to anything that's experimentally tractable.
link |
But what his lab has been able to do
link |
is develop this method where they look at a molecule
link |
and they break it apart into all its component parts.
link |
And so you say you have some elementary building blocks
link |
and you can build up all the ways
link |
of putting those together to make the original object.
link |
And then you look for the shortest path in that space
link |
and you say that's sort of the assembly number
link |
associated to that object.
link |
And if that number is higher,
link |
it assumes that a longer causal history
link |
is necessary to produce that object
link |
or more information is necessary to specify
link |
the creation of that object in the universe.
link |
Now that kind of idea at a superficial level
link |
has existed for a long time.
link |
That kind of idea as a physical observable of molecules
link |
is completely novel.
link |
And what his lab has been able to show
link |
is that if you look at a bunch of samples
link |
of nonbiological things and biological things,
link |
there's this kind of threshold of assembly
link |
where as far as the experimental evidence is
link |
and also your intuition would suggest
link |
that nonbiological systems don't produce things
link |
with high assembly number.
link |
So this goes back to the idea
link |
like a protein's not gonna spontaneously
link |
fluctuate into existence on the surface of Mars.
link |
It requires an evolutionary process
link |
and a biological architecture to produce a protein.
link |
You generalize that argument,
link |
a complex molecule or a cup or a desk ornament
link |
in this sort of abstract idea of assembly spaces
link |
as being the causal history of objects.
link |
And you can talk about the shortest path
link |
from elementary objects to an object
link |
given an elementary set of operations.
link |
And you can experimentally measure that with a mass spec.
link |
And that's basically sort of the idea.
link |
That's really fascinating.
link |
I can't get out of my head.
link |
I'd start imagining Legos.
link |
And all the Legos I've ever built and how many steps,
link |
what is the shortest path to the final little Lego castles?
link |
So yeah, so then like asking about going to look
link |
for alien life, the idea is most the instruments
link |
that NASA builds, for example,
link |
or any of the space agencies looking for life in the universe
link |
are looking for chemical correlates of life, right?
link |
But here we have something that is based
link |
on properties of molecules.
link |
It's not a chemical correlate.
link |
It doesn't care about the molecule.
link |
It cares about what is the history necessary
link |
to produce this molecule?
link |
How complex is it in terms of how much time is needing,
link |
how much information is required to produce it?
link |
So when you observe a thing on another planet,
link |
you're essentially, the process looks like reverse engineering,
link |
trying to figure out what is the shortest path
link |
to create that thing?
link |
Yeah, so most, yeah.
link |
And I would say most examples of biology or technology
link |
don't take the shortest path, right?
link |
But the shortest path is a bound on how hard it is
link |
for the universe to make that.
link |
Yeah, and I guess you and Lee are saying
link |
that there's a heuristic, that's a good metric
link |
for like better perhaps than chemical correlates.
link |
Yes, because it's not contingent on looking
link |
for the chemistry of life on Earth, on other planets.
link |
And it also has a deeper explanatory framework
link |
associated to it as far as the kind of theory
link |
that we're trying to develop associated to what life is.
link |
And I think this is one of the problems I have in my field
link |
personally in astrobiology is people observe something
link |
on Earth, say oxygen in the atmosphere
link |
or an amino acid in a cell.
link |
And then they say, let's go look for that on another planet.
link |
Let's look for oxygen on exoplanets
link |
or let's look for amino acids on Mars.
link |
And then they assume that's a way of looking for life or even
link |
phosphine on Venus.
link |
But there's all these examples of let's look for one molecule.
link |
A molecule is not life.
link |
Life is a system that patterns particular structures
link |
That's what it is.
link |
And it doesn't care what molecules are there.
link |
It's something about the patterns and that structure
link |
And if you're looking for a molecule,
link |
you're not testing any hypotheses about the nature
link |
It doesn't tell me anything if we discover oxygen on exoplanet
link |
about what kind of life is there, just oxygen on exoplanet.
link |
I guess I think when you think about the question,
link |
are we alone in the universe?
link |
That's a pretty frickin deep question.
link |
It should have a frickin deep answer.
link |
It shouldn't just be there's a molecule on an exoplanet.
link |
Wow, we solved the problem.
link |
It should tell us something meaningful about our existence.
link |
And I feel like we've fallen short
link |
on how we're searching for life in terms of actually searching
link |
for things like us in this kind of deeper way.
link |
But how do you do that initial kind of say,
link |
I'm walking down the street and I'm
link |
looking for that double take test of like,
link |
what the hell is that?
link |
Like that initial, like how do we
link |
look for the possibility of weirdness,
link |
the possibility of high assembly number?
link |
What would aliens look like if they don't have two eyes
link |
It's fine with you.
link |
I wouldn't probably always solve the problem.
link |
There's another Nobel Prize in there somewhere.
link |
Yeah, somewhere in there.
link |
Well, I think it's kind of, so there is a bias here, right?
link |
So we've evolved to recognize life on Earth, right?
link |
Like children at a very early age
link |
can tell the difference between a puppy and a plant,
link |
and then the plant and a chair, for example.
link |
Like it seems innate.
link |
And so I think, and also because we're life,
link |
I think there's this implicit bias
link |
that we should know it when we see it,
link |
and it should be completely obvious to us.
link |
But there are a lot of features of our universe
link |
that are not completely obvious to us,
link |
like the fact that this table is made of atoms
link |
and that I'm sitting in a gravitational potential well
link |
And I guess my point with this is,
link |
I think life is much less obvious than we think it is.
link |
And so it could be in many more forms than we think it is.
link |
And I guess let's go back to the point about being open minded
link |
that we may not know what alien life looks like.
link |
It might not even be possible to interact with alien life,
link |
because maybe something about our informational lineage,
link |
it makes it impossible for information from an alien
link |
to be copied to us.
link |
Therefore, there's no, so to speak, communication channel.
link |
And I don't mean verbal communication.
link |
Just it's not in our observational space.
link |
Like there's fundamental questions
link |
about why we observe the universe in position rather
link |
than momentum, but we also observe it
link |
in terms of certain informational patterns and things.
link |
Like that's what our brain constructs.
link |
And maybe aliens just interact with a different part
link |
of reality than we do.
link |
That's wildly speculative.
link |
But I think it's possible and I think it's consistent
link |
So I think the best ways we can ask questions
link |
are about life and chemistry and asking questions
link |
about if information is a real physical thing,
link |
what would its signatures be in matter?
link |
And how do we recognize those?
link |
And I think the ones that are most obvious
link |
are the ones I've already articulated.
link |
You have these objects that seem completely improbable
link |
for the universe to produce because the universe doesn't
link |
have the design of that object in the laws.
link |
So therefore, an object had to evolve.
link |
We call it evolution, but it had to be produced
link |
by the universe that then had all of the possible tasks
link |
to make that object specified.
link |
I mean, there's some like, there's an engineering question
link |
here of are there sensors we can create
link |
that can help us discover certain pockets
link |
of high assembly aliens?
link |
Like, I mean, there is a hope setting dogs and chairs
link |
There's a hope that visually and we could detect.
link |
Like, because our universe, I mean, at least the way
link |
we look at it now, like this three dimensional space
link |
time, we can visually comprehend it,
link |
it's interesting to think like, if we got to hang out,
link |
you know, if there's an alien in this room,
link |
like, would we be able to detect it
link |
with our current sensors?
link |
Not the fancy kinds, but like webcams.
link |
Like, say standing over there?
link |
Yeah, standing over there.
link |
Or maybe like in this carpet, see,
link |
there's all these kinds of patterns, right?
link |
I don't know if this carpet is an alien.
link |
Well, so I see what you're saying.
link |
So assembly theory is pretty general.
link |
Like, I mean, we've been applying it to molecules
link |
because it makes sense to apply it to molecules,
link |
but it's supposed to explain life, you know,
link |
like the physics of life.
link |
So it should explain, you know, the things in this room
link |
in addition to molecules.
link |
So I guess, and you can apply it to images and things.
link |
So I guess the idea, you know, you could explore
link |
is just looking at everything on planet Earth
link |
in terms of its assembly structure
link |
and then looking for things
link |
that aren't part of our biological lineage.
link |
If they have high assembly, they might be aliens on Earth.
link |
I mean, that is a very kind of rigorous
link |
computer vision question.
link |
Can we visually, is there a strong correlation
link |
between certain kind of high assembly objects
link |
when they get to the scale where they're visually observable
link |
and some, like when it's, say, projected onto a 2D plane,
link |
can we figure out something?
link |
I'm glad you brought up a computer vision point
link |
because for a while I had this kind of thought in my mind
link |
that we can't even see ourselves clearly.
link |
So one of the things, you know,
link |
people are worried about artificial intelligence
link |
for a lot of reasons, but I think it's really fascinating
link |
because it's like the first time in history
link |
that we're building a system
link |
that can help us understand ourselves.
link |
So like, you know, people talk about AI physics,
link |
but like, you know, when I look at another person,
link |
I don't see them as a four billion year lineage,
link |
but that's what they are.
link |
And so is everything here, right?
link |
So imagine that we build artificial systems
link |
that could actually see that feature of us.
link |
What else would they see?
link |
And I think that's what you're asking.
link |
And I think that would be so cool.
link |
I want that to happen,
link |
but I think we're a little ways off from it, but yeah.
link |
We're going there, I hope.
link |
Okay, let me ask you, I apologize ahead of time,
link |
but let me ask you the internet question.
link |
So you're a physicist, you ask rigorous questions
link |
about the physics of existence
link |
and these models of high assembly objects.
link |
Now, when the internet would see an alien,
link |
they would ask two questions.
link |
One, can I eat it?
link |
And two, can I have sex with it?
link |
All the existential questions, those are very important.
link |
The internet is very sophisticated.
link |
It's got in our basal cognition pretty good.
link |
So you kind of mentioned that it's very difficult.
link |
It's possible that we may not be
link |
even able to communicate with it.
link |
But the internet has more hope than we do.
link |
Yeah, it's a hopeful place.
link |
Do you think in terms of like interacting
link |
on this very primal level of sharing resources,
link |
like what would aliens eat?
link |
What would we eat?
link |
Would we eat the same thing?
link |
Could we potentially eat each other?
link |
One person eats the other or the aliens eat us?
link |
And the same thing with not sex in general reproduction,
link |
but genetically mixing stuff.
link |
Like would we be able to mix genetic information?
link |
Maybe not genetic, but maybe information, right?
link |
And I think part of your question is like,
link |
so if you think of life as like this history
link |
of events that happen in the universe,
link |
like there's this question of like,
link |
how divergent are those histories, right?
link |
So when we get to the scale of technology,
link |
it's possible to imagine,
link |
imagine, although we can't even do it,
link |
like imagine all the possible technologies
link |
that could exist in the universe.
link |
But if you think about all the possible chemistries,
link |
somehow that seems like a lower dimensional space
link |
and a lower set of possibilities.
link |
So it might be that like when we interact with aliens,
link |
we do have to go back to those more basal levels
link |
to figure out sort of what the map is, right?
link |
Like the sort of where we have a common history.
link |
We must have a common history somewhere in the universe,
link |
but in order to be able to actually interact
link |
in a meaningful way, you have to have some shared history.
link |
I mean, the reason we can exchange genetic information
link |
in each other's food or eat each other as food
link |
is because we have a shared history.
link |
So we have to find that shared history.
link |
We have to find the common ancestor
link |
and this causality map, the causality tree.
link |
Something, yes, yes.
link |
And we have a last universal common ancestor
link |
for all life on earth, which I think is sort of the nexus
link |
of that causality map for life on earth.
link |
But the question is, where would other aliens diverge
link |
That's really interesting.
link |
So say there's a lot of aliens out there in the universe,
link |
each set of organisms will probably have like a number,
link |
you know, like Erdos number of like how far,
link |
like how far our common ancestor is.
link |
And so the closer the common ancestor, like it is on earth,
link |
the more likely we are to be able
link |
to have sexual reproduction.
link |
Well, it's like sort of like humans having
link |
common culture and languages, right?
link |
Language, communication.
link |
It might take a lot of work though with an alien
link |
because you really have to get over a language barrier.
link |
So it's communication, it's resources.
link |
I mean, it's all the whole, and I think tied
link |
into that is the questions of like who's going to harm who.
link |
And actually definitions of harm.
link |
And whether your parents approve,
link |
you know, all those kind of questions.
link |
Whether the common ancestor approves.
link |
Yeah, this is very true.
link |
How many alien civilizations do you think are out there?
link |
I don't have intuition for that,
link |
which I have always thought was deeply intriguing.
link |
So, and part of this, I mean, I say it specifically
link |
as I don't have intuition for that
link |
because it's like one of those questions
link |
that you feel around for a while
link |
and you really just, you can't see it,
link |
even though it might be right there.
link |
And in that sense, it's a little like
link |
the quantum to classical transition.
link |
You're like really talking about two different
link |
And I think that's kind of part of the problem
link |
once we understand the physics,
link |
that question might become more meaningful.
link |
But there's also this other issue,
link |
and this was really instilled on me by my mentor,
link |
Paul Davies, when I was a postdoc,
link |
because he always talks about how,
link |
you know, whether aliens are common or rare
link |
is kind of just, you know, it's like,
link |
you know, it follows a wave of popularity
link |
and it just depends on like the mood of,
link |
you know, what the culture is at the time.
link |
And I always thought that was kind of an intriguing
link |
observation, but also there's this,
link |
you know, a set of points about,
link |
if you go by the observational evidence,
link |
which we're supposed to do with scientists, right?
link |
You know, we have evidence of us
link |
and one original life event from which we emerged.
link |
And people want to make arguments
link |
that because that event was rapid,
link |
or because there's other planets
link |
that have properties similar to ours
link |
that that event should be common.
link |
But you actually can't reason on that
link |
because our existence observing that event
link |
is contingent on that event happening,
link |
which means it could have been completely improbable
link |
And Brandon Carter like clearly articulated that
link |
in terms of anthropic arguments a few decades ago.
link |
So there is this kind of issue
link |
that we have to contend with dealing with life
link |
that's closer to home than we have to deal with
link |
with any other problems in physics,
link |
which we're talking about the physics of ourselves.
link |
And when you're asking about the original life event,
link |
that event happening in the universe,
link |
at least as like our existence is contingent on it.
link |
And so you can think about sort of fine tuning arguments
link |
But the sort of otter part of it is like,
link |
when I think about how likely it is,
link |
I think it's because we don't understand this mechanism yet
link |
about how information can be generated spontaneously.
link |
That I like, cause I can't see that physics clearly yet,
link |
even though I have a lot of, you know,
link |
like some things around the space of it in my mind,
link |
I can't articulate how likely that process is.
link |
So my honest answer is, I don't know,
link |
and it sometimes feels like a cop out,
link |
but I feel like that's a more honest answer
link |
and a more meaningful way of making progress
link |
than what a lot of people want to do,
link |
which is say, oh, well, we have a one in 10 chance
link |
of having on an exoplanet with Earth like properties
link |
because there's lots of Earth like planets out there
link |
and life happened fast on Earth.
link |
Well, so kind of a follow up question,
link |
but as a side comment, what I really am enjoying
link |
about the way you're talking about human beings
link |
is you always say, and not to make yourself conscious
link |
about it, cause I really, really enjoy it.
link |
Yes. You don't say humans.
link |
You say, cause oftentimes like, you know,
link |
I don't know, evolutionary biologists
link |
will kind of put yourself out as an observer,
link |
but you're, it's kind of fascinating to think
link |
that you as a human are struggling
link |
about your own origins.
link |
Yes, that's the problem.
link |
And yeah, and I think, I don't do that deliberately,
link |
but I do think that way.
link |
And this is sort of the inversion from the logic of physics
link |
because physics as it's always been constructed
link |
has treated us as external observers of the universe.
link |
And we are not part of the universe.
link |
And this is why the problem of life, I think,
link |
demands completely new thinking
link |
because we have to think about ourselves
link |
as minds that exist in the universe
link |
and are at this particular moment in history
link |
and looking out at the things around us
link |
and trying to understand what we are inside the system,
link |
not outside the system.
link |
We don't have descriptions at a fundamental level
link |
that describe us as inside the system.
link |
And this was my problem with cellular automata also.
link |
You're always an external observer for a cellular automata.
link |
You're not in the system.
link |
What does the cellular automata look like from the inside?
link |
I think you just broke my brain with that question.
link |
Exactly, but that's the problem.
link |
I thought about that for a long time.
link |
But I'm going to, yeah, that's a really clean formulation
link |
of a very fundamental question because you can only,
link |
to understand cellular automata, you have to be inside of it.
link |
But as a human, sort of a poetic, romantic question,
link |
does it make you sad, does it make you hopeful
link |
whether we're alone or not?
link |
Like in the different possible versions of that,
link |
if we're the highest assembly object in the entire universe,
link |
does that give you...
link |
At this moment in time, maybe.
link |
At this moment in the causal chain.
link |
Because we make, I assume we have a future.
link |
Well, we definitely have a future.
link |
The question is where that future decreases the assembly.
link |
Like it could be we're at the peak
link |
or we could be just...
link |
That would be inconsistent with the physics in my mind.
link |
But so I should give a caveat.
link |
I've given the caveat that I'm biased as a physicist,
link |
but I'm also biased as an eternal optimist.
link |
So pretty much all of my modes of operation
link |
for building theories about the world
link |
are not like an Occam's razor,
link |
what's the simplest explanation,
link |
but what's the most optimistic explanation?
link |
And part of the reason for that
link |
is if you really think explanations have causal power
link |
in the sense that the fact that we have theories
link |
about the world has enabled technologies
link |
and physically transformed the world around us,
link |
I think I have to take seriously
link |
that as a part of the physics I wanna describe
link |
and try to build theories of reality
link |
that are optimistic about what's coming next
link |
because the theories are in part the causes
link |
of what comes next.
link |
So there could be a physics of hope
link |
or a physics of optimism in there too.
link |
Is that seems like also, I mean,
link |
optimism does seem to be a kind of engine
link |
that results in innovation.
link |
So this is dry, like why the hell
link |
are we trying to come up with new stuff?
link |
Oh, so I made this point about thinking life
link |
is the physics of existence
link |
and it's not just the physics of existence,
link |
it's the physics of more things existing.
link |
So I think one of these drives of like...
link |
Like optimism, the story.
link |
So if you like, people like entropy,
link |
I don't like entropy as it was formulated in the 1800s.
link |
I think it's an antiquated concept,
link |
but this idea of maximizing over the possible number
link |
of states that could exist.
link |
Imagine the universe is actually trying to maximize
link |
over the number of things that could physically exist.
link |
What would be the best way to do that?
link |
The best way to do that would be
link |
evolve intelligent technological things
link |
that could explore that space.
link |
It's okay, that's talking about alien life
link |
out there in the universe.
link |
But you've also earlier in the conversation
link |
mentioned the shadow biosphere.
link |
So is it possible that we have weird life here on earth
link |
that we're just not...
link |
Like even in a high assembly formulation of life,
link |
that we're just not paying attention to, we're blind to.
link |
Like life we're potentially able to detect
link |
but we're blind to.
link |
And maybe you could say, what is the shadow biosphere?
link |
Yeah, the shadow biosphere is this idea
link |
that there might have been other original life events
link |
that happened on earth that were independent
link |
from the original life event that led to us
link |
and all of the life that we know on earth.
link |
And therefore there could be aliens
link |
in the sense they have a different origin event
link |
And it was proposed by a number of people,
link |
but one of them was Paul Davies
link |
that I mentioned earlier as my mentor.
link |
And he has a really cute way of saying
link |
that aliens could be right under our noses
link |
or even in our noses with a British accent,
link |
But anyway, so the idea is like,
link |
it could literally be anywhere around us.
link |
And if you think actually about the discovery
link |
of like viruses and bacteria,
link |
for a long time they were kind of a shadow biosphere.
link |
It was life that was around us, but invisible.
link |
But this takes it a little bit further
link |
and saying that all of those examples,
link |
viruses, bacteria, and everything that we've discovered
link |
so far has this common ancestry
link |
in the last universal common ancestor of life on earth.
link |
So maybe there was a different origin event
link |
and that life is weirder still
link |
and might be among us and we could find it.
link |
We don't have to go out and start for aliens
link |
just here on earth.
link |
Do you think that's a serious possibility
link |
that we should explore with the tools of science?
link |
Like this would be a serious effort?
link |
I think yes and no.
link |
And I mean, yes, because I think it's a serious hypothesis
link |
and I think it's worth exploring
link |
and it's certainly more economical
link |
to look for signs of alien life on earth
link |
than it is to go and build spacecraft
link |
and send robots to other planets.
link |
And that was one of the reasons it was proposed is,
link |
well, if we do find an example
link |
of another original life on earth,
link |
it's hugely informative
link |
because it means the original life is not a rare event.
link |
If it happened twice on the same planet,
link |
that means it's probably pretty probable
link |
given conditions are right.
link |
So it has huge potential scientific impact,
link |
not to mention the fact that you might have
link |
like biochemistry and stuff that's informative
link |
for like medicine and stuff like that.
link |
But I think that the thing for me that's challenging about it
link |
and this really comes from my own work
link |
like thinking about life as a planetary scale process
link |
and also trying to understand
link |
sometimes what I call like the statistical mechanics
link |
of biochemistry but large scale statistical patterns
link |
in the chemistry that life uses on earth.
link |
There are a lot of regularities there
link |
and life does seem to have planetary scale organization
link |
that's consistent even with some of the patterns
link |
that we see at the individual scale.
link |
So if you think life is a planetary scale phenomena
link |
and the chemistry of life has to be sort of not just,
link |
it's not an individual is not necessarily
link |
the fundamental unit of life, right?
link |
The fundamental unit of life is these informational lineages
link |
and they're kind of, they intersect over spatial scales.
link |
So everything on earth is kind of related
link |
by the common causal history.
link |
So it's hard for me based on the way I think about the physics
link |
and also some of the stuff that my group has done
link |
to really think that there could be evidence
link |
or there could be a second sample of life on earth.
link |
But I think there are ways that we need to be more concrete
link |
And I have thought a little bit about like you can represent
link |
the chemistry in an individual cell as a network.
link |
And then those networks, something my group has shown
link |
actually scale with the same property.
link |
So ecosystems have the same properties as individuals
link |
as planetary scale.
link |
And then you could imagine if you had alien chemistry
link |
intermixed in there, that scaling would be broken.
link |
So if there's some robustness property
link |
or something associated to it
link |
and you get alien chemistry in there,
link |
it just breaks everything.
link |
And you don't have a planetary ecosystem functioning
link |
and individuals functioning across all these scales.
link |
So I guess what I'm arguing is life is not a scale dependent
link |
phenomenon, it's not just cellular life.
link |
So if you have a shadow biosphere,
link |
it has to be integrated with all of these other scales.
link |
And that would lose the meaning
link |
of the word shadow biosphere, I guess.
link |
So it's an open question, right?
link |
And I think it would tell us a lot.
link |
So there has been very minimal effort of people
link |
to look for a shadow biosphere.
link |
But then the question, it could be possible
link |
that there's like sufficiently distinct planets
link |
within one planet, meaning like environments
link |
within one planet.
link |
Like, I don't know.
link |
I've been looking recently because of having a chat
link |
with Catherine DeClerc about Io, the moon of Jupiter,
link |
that's like all volcanoes and volcanoes, a bad ass.
link |
But like imagining life inside volcanoes, right?
link |
Like it seems like sufficiently chemically different
link |
like to be living in the darkness where there's a lot
link |
of heat and maybe you can have different earths
link |
Or like if you go deep enough in the crust,
link |
maybe there's like a layer where there's no life
link |
and then there's suddenly life again.
link |
And maybe those, you know, lizard men
link |
or whatever they are that people dream about
link |
are really down there.
link |
I know that's a little flippant,
link |
but really like there could be like chemical cycles
link |
deep in the earth's crust that might be alive
link |
and are completely distinct in chemical origin
link |
Right, that wouldn't be interacting with each other.
link |
Yeah, and that's one of the proposals
link |
for the shadow biosphere is like sometimes people talk
link |
about it as being geologically or geographically distinct
link |
that it might be, you know, you have no life
link |
for this region and then a different example.
link |
And then sometimes people talk about it
link |
being chemically distinct that the chemistry
link |
is sufficiently different, that it's completely orthogonal
link |
or non interacting with our chemistry.
link |
It seems to me at least the chemistry
link |
is a more powerful boundary.
link |
It just seems like life finds a way literally to travel.
link |
What do you think about all these UFO sightings?
link |
So to me, it's really inspiring.
link |
It's yet another localized way to dream about
link |
the mysterious that is out there.
link |
So I've actually been more intrigued
link |
by the cultural phenomena UFOs
link |
than the phenomena UFOs themselves
link |
because I think it's intriguing
link |
about how we are preparing ourselves mentally
link |
for understanding others
link |
and how we have thought about that historically
link |
and what the sort of modern incarnations of that are.
link |
It's more like I want an explanation for us.
link |
That's my motivation.
link |
And having some, you know, streaks across the sky
link |
or something and saying that's aliens.
link |
It doesn't tell you anything.
link |
So unless you have a deeper explanation
link |
and you have, you know, more lines of, you know,
link |
where is this gonna take us in the future?
link |
It's just not as interesting to me
link |
as the problem of understanding life itself
link |
and aliens as a more general phenomenon.
link |
I do think it's just as he said,
link |
a good way to psychologically and sociologically
link |
prepare ourselves to sort of like,
link |
what would that look like?
link |
And very importantly,
link |
which is what a lot of people talk about politically.
link |
Sort of there's this idea from the,
link |
so it came from the Soviet Union of like the Cold War
link |
and we have to hide secrets.
link |
There's some way in us searching for life
link |
and other planets or our searching for life in general,
link |
the way we've done government in the past,
link |
we tend to think of all new things
link |
as potential military secrets.
link |
So we want to hide them.
link |
And one of the ways that people kind of look
link |
at UFO sightings is like,
link |
maybe we shouldn't hide this stuff.
link |
Like what is the government hiding?
link |
I think that's a really, you know,
link |
in one sense it's a conspiratorial question,
link |
but I think in another,
link |
it's an inspiration to change the way we do government
link |
to where secrets don't,
link |
maybe there are times when you want to keep secrets
link |
as military secrets,
link |
but maybe we need to release a lot more stuff
link |
and see us as a human species as together in this whole search.
link |
Yeah, the public engagement part there is really interesting.
link |
And it's almost like a challenge
link |
to the way we've done stuff in the past
link |
in terms of keeping secrets.
link |
When they're not, so like the first step,
link |
if you don't know how something works,
link |
if there's a mysterious thing,
link |
the first instinct should not be like, let's hide it.
link |
Let's put it in the closet.
link |
So that the Chinese or the Russian government
link |
or whatever government doesn't find it.
link |
Maybe the first instinct should be, let's understand it.
link |
Perhaps let's understand it together.
link |
No, I think that's good.
link |
And something I realized recently
link |
that I never thought was gonna be a problem,
link |
but I think this actually helps with quite a bit
link |
is because so many people nowadays
link |
believe we've already made contact
link |
that as an astrobiologist,
link |
if we actually want to understand life
link |
we kind of have to deconstruct the narratives
link |
we've already built from ourselves
link |
and kind of unteach ourselves
link |
that we've learned about aliens
link |
and then reteach ourselves.
link |
So there's this really interesting sort of dialogue there
link |
and making it open to the public
link |
that they actually have to think critically about it
link |
and they see the evidence for themselves,
link |
I think is really important for that process.
link |
Yeah, that aliens might be way weirder than we can imagine.
link |
Yes, I'm pretty sure they're probably weirder
link |
than we can imagine.
link |
Okay, we've in 2020 and still living through a pandemic,
link |
setting the political and all those kinds of things aside,
link |
I've always found viruses fascinating
link |
as living as dynamical systems.
link |
I was gonna say living systems,
link |
but I've always kind of thought of them as living,
link |
but that's a whole nother kind of discussion.
link |
Maybe it'd be great to put that on the table.
link |
One, do you find viruses beautiful slash terrifying?
link |
And two, do you think they're living things?
link |
Or there's some aspect to them
link |
per our discussion of life that makes them living?
link |
I mean, living in a pandemic saying viruses are beautiful,
link |
it's probably a hard thing,
link |
but I do find them beautiful to a degree.
link |
I think even in the sense of mediating a global pandemic,
link |
there's something like deeply intriguing there
link |
because these are tiny, tiny little things, right?
link |
And yet they can essentially cause a seizure,
link |
handicap an entire civilization at a global scale.
link |
So just that intersection between our perceived invincibility
link |
and our susceptibility to things
link |
and also the interaction across scales of those things
link |
is just a really amazing feature of our world.
link |
Most technology, whether it's viruses or AI,
link |
that can scale in an exponential way,
link |
like kind of run as opposed to like one thing makes
link |
another thing, makes another thing.
link |
It's one thing makes two things
link |
and those two things make four things.
link |
And then like that kind of process
link |
also seems to be fundamental to life.
link |
And it's terrifying because in a matter of,
link |
in a very short time scale,
link |
if it's good at being life, whatever that is,
link |
it can quickly overtake the other competing forms of life.
link |
And that's scary both for AI and for viruses.
link |
And it seems like understanding these processes
link |
that are underlying viruses.
link |
And I don't mean like on the virology or biology side,
link |
but on some kind of more computational physics perspective
link |
as we've been talking about,
link |
seems to be really important to figure out
link |
how humans can survive along with these kinds of,
link |
all this kind of life.
link |
And perhaps becoming a multi planetary species
link |
is a part of that.
link |
Like there's no, maybe like we'll figure out
link |
from a physics perspective is like, there's no way
link |
any living system can be stable for a prolonged period of time
link |
and survive unless it expands exponentially throughout.
link |
Like we have to multiply.
link |
Otherwise anything that doesn't multiply exponentially
link |
will die eventually.
link |
Maybe that's a fundamental law.
link |
You know, I always get really bothered by these Darwinian narratives
link |
that are like the fittest replicator wins and things.
link |
And I just don't feel like that's exactly what's going on.
link |
I think like the copying of information is sort of
link |
ancillary to this other process of creativity, right?
link |
So like the drive is actually, the drive is creativity,
link |
but if you wanna keep the creativity that's existed
link |
in the past, it has to be copied into the future.
link |
So replication, like if you, so that for me is,
link |
so I had this set of arguments with Michael Lachman
link |
and Lee Cronin about the like life being about persistence.
link |
They thought it was about persistence
link |
and like survival of fittest kind of thing.
link |
And I'm like, no, it's about existence.
link |
It's like, cause when you're talking about that,
link |
it's easy to say that in retrospect,
link |
you can post select on the things that survived
link |
and then say why they survived,
link |
but you can't do that going forward.
link |
That's really profound.
link |
That survival is just a nice little side effect feature
link |
of maximizing creativity, but it doesn't need to be there.
link |
That's really beautiful.
link |
Yeah, that's really.
link |
Like I said, I like optimistic theories.
link |
Well, I don't know if that's optimistic.
link |
That could be terrifying to people because,
link |
because, you know, a system that maximizes creativity
link |
may very quickly get rid of humans for some reason.
link |
If it comes up with some other creative,
link |
I mean, forms of existence.
link |
Right, this is the AI thing is like the moment you have
link |
an AI system that can flourish in the space of ideas
link |
or in some other space, much more effectively than humans.
link |
And it's sufficiently integrated into the physical space
link |
to be able to modify the environment.
link |
I think we'll just be like the core genetic architecture
link |
or something will be like the DNA for AI, right?
link |
It's like we haven't lost the past informational
link |
architectures on this planet.
link |
They're still there.
link |
Yeah, so the AI will use our brains in some part
link |
to like ride, like accelerate the exchange of ideas.
link |
That's the neural link dream is that,
link |
well, the humans will be still around
link |
because you're saying architecture.
link |
Yeah, but I don't even think they necessarily need
link |
to tap into our brains.
link |
I mean, just collectively we do interesting things.
link |
What if they were just using like the patterns
link |
in our communication or something?
link |
Oh, without controlling it, just observing?
link |
Well, I don't know.
link |
In what sense do you control the chemistry
link |
happening in your body?
link |
I mean, I obviously don't know.
link |
I'm just, like the way I look at, like people look at AI
link |
and then they look at this thing that's bigger than us
link |
and is coming in the future and is smarter than us.
link |
And I think though that looking at the past history
link |
of life on the planet and what information it has been doing
link |
for the last four billion years is probably very informative
link |
to asking questions about what's coming next.
link |
And I don't, one is planetary scale transitions
link |
are really important for new phases.
link |
So the global internet and sort of global integration
link |
of our technology, I think is an important thing.
link |
So that's again, life is a planetary scale phenomena,
link |
but we're an integrated component of that phenomenon.
link |
I don't really see that the technology is gonna replace us
link |
It's just gonna keep scaffolding and building.
link |
And I also don't have an idea
link |
that we're gonna build AI in a box.
link |
I think AI is gonna emerge.
link |
AGI to be is a planetary scale phenomena
link |
that's gonna emerge from our technology.
link |
Planetary scale phenomena.
link |
But do you think an AGI is not distinct from humans?
link |
Where the whole package comes as a planetary scale phenomena.
link |
And that goes back to the fact
link |
that like you were asking questions about you
link |
as an individual, like what are you as an individual?
link |
You're like a packet of information that exists
link |
in the particular physical thing that is you.
link |
We're all just packets of information.
link |
And some of us are aggregates in certain ways,
link |
but it's all just kind of exchanging
link |
and propagating and processing.
link |
Is your packet of information
link |
that you've continually referred to as Sarah
link |
afraid of the dissipation of the death of that packet?
link |
Are you afraid of death?
link |
Does death have meaning in this process of creativity?
link |
I think I have the natural biological urge
link |
that everyone has to fear death.
link |
I think the thing that I think is interesting
link |
is if I think about it rationally,
link |
I'm not necessarily afraid of death for me
link |
because I won't be aware of being dead.
link |
But I am afraid like for my kids
link |
because it matters to them if I die.
link |
So again, like I think death becomes more significant
link |
as a collective property, not as an individual one.
link |
Yeah, but isn't there something to fear
link |
about the fact that the way like the creative,
link |
the complexity of information
link |
that's been like created in you.
link |
The fact that it kind of breaks apart and disappears.
link |
It doesn't, but I don't think it disappears.
link |
It's just not me anymore.
link |
Right, so you're, but that process of you
link |
it being not you anymore that doesn't scare you?
link |
Of course it does.
link |
The mystery of it.
link |
But I guess I'm heartened by the fact
link |
that there will be some imprints of the fact
link |
that I existed still in the universe after I leave it.
link |
Yeah, but there'll be a, oh, okay.
link |
And also that has to do with my perception of time, right?
link |
So, I perceive time as flowing,
link |
but that might not be the case.
link |
I mean, this is standard physicist's comfort
link |
is every moment exists and there's no,
link |
and the flow of time is just our perception
link |
So you can travel back in time and that's comforting?
link |
Like from a physicist's perspective?
link |
No, no, no, I'm not talking about traveling back in time.
link |
I'm just saying that the moments in the past still exist.
link |
Now, whether the moments in the future exist or not
link |
is a different question.
link |
That's not comforting to me in terms of death.
link |
The flow of time does not...
link |
I think there's no comfort in the face of death.
link |
For what we are, because we like existing.
link |
And I think it's especially true if you love life
link |
and you love what life is.
link |
Do you think there's a certain sense in which
link |
the fear of death or the fear of nonexistence,
link |
maybe fear is not the right word,
link |
is the actual very phenomena that gives birth to existence?
link |
Like death is fundamental, like this,
link |
it just feels like freaking out, oh shit,
link |
this ride ends is actually like the...
link |
That's the thing that gives birth to this whole thing.
link |
That like it's constantly,
link |
it's matter constantly freaking out about the fact
link |
that it's gonna be the most...
link |
No, I think things like to exist.
link |
I think they wanna exist.
link |
Yeah, there's a desire whatever to exist.
link |
Yeah, there's a drive to exist
link |
and there's a drive for more things to exist.
link |
I guess, yeah, I like existing, I like it a lot.
link |
And I don't know it any other way.
link |
See, I don't even know if I like existing,
link |
I think I really don't like not existing.
link |
Yes, yeah, that's you.
link |
Yeah, maybe it's that.
link |
Some days I might like existing less than others.
link |
Yes, but I think those are like surface feelings.
link |
There is some seems like there's something fundamental
link |
about wanting to exist.
link |
No, I think that's right, but I think to your point
link |
that that might go back to the more fundamental idea
link |
that if life is the physics of existence
link |
and maximizing existence, individual organisms,
link |
of course, wanna maximize their existence
link |
and everything wants to exist.
link |
But I guess for me, the small comfort is
link |
my existence matters to future existence.
link |
Speaking of future existence,
link |
is there advice you can give
link |
to future pockets of existences,
link |
AKA young people about life?
link |
You've had, you've worn many hats,
link |
you've taken on some of the biggest problems
link |
Is there advice you can give to young people
link |
about life, about career, about existing?
link |
Maybe not about the last one.
link |
You know, a lot of people ask me this question
link |
about like working on such hard problems,
link |
how can you make a successful career out of that?
link |
But I think for me, it couldn't be otherwise.
link |
I have to be fulfilled.
link |
You have to work on things you care about
link |
and that's always kind of driven me.
link |
And that's been discipline, department,
link |
and sort of superficial level problem independent
link |
because I started at community college actually
link |
and I was taking a physics class
link |
and I learned about magnetic monopoles
link |
and we didn't know if they existed in the universe
link |
but we could predict them and we could go look for them.
link |
And I was so deeply intrigued by this idea
link |
that we had this mathematical formula
link |
to go look for things.
link |
And then I wanted to become a theoretical physicist
link |
but that actually wasn't my driving question.
link |
I realized my driving question is the nature
link |
of the correspondence between our minds
link |
and physical reality and what we are.
link |
And that question's very deep
link |
so you can work across a lot of fields doing that.
link |
But I think without that driving question,
link |
I never would have been able to do all the things
link |
It's really the passion that drives it.
link |
And usually when students ask me these kind of questions,
link |
I tell them like, you have to find something
link |
you really care about working on
link |
because if you don't really care about it,
link |
A, you're not gonna be your best at it
link |
and B, it's not gonna be worth your time.
link |
Why would you spend your time working
link |
on something you're not interested in?
link |
So find the driving question.
link |
Yeah, find the driving question.
link |
Find your passion.
link |
I mean, I think passion makes a huge difference
link |
in terms of creativity, talent and potential
link |
and also being able to tolerate all the hard things
link |
that come with any career or life.
link |
Yeah, I've had a bunch of moments in my life
link |
where I've just been captivated
link |
by some beautiful phenomena
link |
and I guess being rigorous about it
link |
and asking what is the question underlying this phenomenon?
link |
Like robots bring a smile to my face
link |
and forming a question of like,
link |
why the hell is this so fascinating?
link |
Why is this specifically the human robot interaction question
link |
that something beautiful is brought to life
link |
when humans and robots interact, understanding that deeply?
link |
I was like, okay, so this is gonna be my life work then.
link |
I don't know what the hell it is,
link |
but that's what I wanna do.
link |
And doing that for whatever the hell gives you
link |
that kind of feeling, I guess is the point.
link |
Am I allowed to ask you a question?
link |
Okay, on that point,
link |
because at this colleague that suggests the idea
link |
that like consciousness might be contagious
link |
and so interacting with things.
link |
You know, it's an interesting idea, right?
link |
So I'm wondering like sort of the motivation there.
link |
Is it the motivation that you want more of the universe
link |
to appreciate things the way we do
link |
and appreciate those interactions
link |
or is it really more the enjoyment
link |
of the human in those interactions?
link |
Like is it, do you know what I'm asking?
link |
See, I think consciousness is created
link |
in the interaction between things.
link |
Yes, yes, I agree.
link |
So the joy is in the creation of consciousness.
link |
I really like the idea that it doesn't just have to be
link |
two humans creating consciousness together.
link |
It could be humans and other entities.
link |
There's a soft line about dogs and other pets and so on.
link |
I mean, I've been calling it love.
link |
It's this beauty of the human experience that's created.
link |
And it just feels like fascinating
link |
that you could do that with a robotic system.
link |
And there's something really powerful, at least to me,
link |
about engineering systems that allow you to create
link |
some of the magic of the human experience.
link |
Cause then you get to understand what it takes,
link |
at least get inklings of what it takes to create consciousness.
link |
And I don't get this, you know,
link |
philosophers get really upset about this idea
link |
that sort of the illusion of consciousness is consciousness.
link |
But I really like the idea of engineering systems
link |
that fool you into thinking they're conscious.
link |
Because that's sufficient to create the magical experience.
link |
Because it's the interaction, yeah.
link |
It's the interaction, yeah.
link |
And this is the Russian hat I wear,
link |
which is like, I think there's an ocean of loneliness
link |
I think we're deeply lonely.
link |
We're not even allowing ourselves to acknowledge that.
link |
And I kind of think that's what love is
link |
between romantic love and friendship,
link |
is two people kind of getting a little bit,
link |
like alleviating for a brief moment.
link |
But we're not, it's not the full aspect of that loneliness.
link |
Like we're desperately alone.
link |
We're desperately afraid of nonexisting.
link |
I have that kind of sense.
link |
And I just want to explore that ocean of loneliness more.
link |
When engineering, like create a submarine
link |
that goes into the depth of that loneliness.
link |
So creating systems that can truly hear you.
link |
Make the universe a less lonely place.
link |
Let me ask you about the meaning.
link |
You've brought up why.
link |
The physics of why.
link |
What do you think is the meaning of our particular planets,
link |
set of existences and the universe in general?
link |
The meaning of life.
link |
Someone once told me as a physicist,
link |
I'm not allowed to ask why questions,
link |
but I don't believe that.
link |
So I think what we are is the creative process
link |
in the universe, I think.
link |
And for me, that's the meaning.
link |
The ability to create.
link |
To create more possibilities and more things to exist.
link |
What does the Yeski as the saying,
link |
beauty will save the world.
link |
What is, is there a connection between creation and beauty?
link |
So is that like, are they,
link |
is beauty a correlate of creation?
link |
I mean, why is it, you know,
link |
a lot of people have asked these kinds of questions,
link |
but like, why is it we have such an emotional response
link |
to intellectual activity or creativity?
link |
And that seems kind of a deep question to me.
link |
Like, it seems very intrinsic to what we are.
link |
So I do have an interest in the questions I asked
link |
because I think they're beautiful.
link |
And I think the universe is beautiful.
link |
And I think that's the reason
link |
the universe is beautiful and I'm just so deeply fascinated
link |
by the fact that I exist at all.
link |
And so maybe, maybe it's that, you know,
link |
that, that intrinsic feeling of beauty
link |
that's in part driving, you know,
link |
the physics of creating more things.
link |
So they could be deeply related in that way.
link |
Well, I don't think there's a better way to end it.
link |
I think this conversation was beautiful.
link |
Thank you so much for wasting all your valuable time
link |
I really, really appreciate it, Sarah.
link |
I hope we get the chance to talk again.
link |
I hope, like I mentioned to you offline,
link |
we get a chance to talk with Lee.
link |
You guys have a beautiful, like, intellectual chemistry
link |
that's fascinating to listen to.
link |
So I'm a huge fan of both of you
link |
and I can't wait to see what you do next.
link |
Thanks for listening to this conversation with Sarah Walker.
link |
And thank you to Athletic Greens, Nutsweet,
link |
Blinkist, and Magic Spoon.
link |
Check them out in the description to support this podcast.
link |
And now let me leave you with some words
link |
from Robert Frost, one of my favorite poets.
link |
In three words, I can sum up everything
link |
I've learned about life.
link |
Thank you for listening.
link |
I hope to see you next time.