#428 – Sean Carroll: General Relativity, Quantum Mechanics, Black Holes & Aliens
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The following is conversation with Shawn Carol, his third time in his podcast. He is a theoretical physicist at john hopkins, host the mines, gave podcast that I personally love and highly recommend, and author of many books, including the most recent books series called the biggest ideas in the universe, the first book of which is titled space, time and motion, and it's on the topic of general relativity.

And the second coming out on may four teeth, so you should definitely preorder IT, is titled quanta and fields, and that one is on the topic of quantum mechanics. Sean is a legit act of the radical physicist, and at the same time is one of the greatest communicators of physics ever. I highly encourage you listen to his podcast, read his books in, preorder the new book to support his work.

This was, as always, a big honour and a pleasure for me. And now a quick you second mention, responsable checked them out in the description is the best way to support this podcast. We got hidden layer for securing your AI models, clock for protecting a personal information, notion for team collaboration, and amazing, no taking chap fy for well selling stuff on the internet, and next week for business measurement software.

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In book one of the series, the biggest ideas in the universe called space time motion, you take on classical mechanics, general relativity, by taking on the main equation of general relativity, making IT a accessible, easy to understand. So maybe at the high level, what is general relativity? What's a good way? Started to try to explain IT.

Probably the best way is to started to try explain IT is special relativity, which came first? Nineteen, no five, IT was the culmination ation, right? Many decades of people putting things together.

But I was einstein in one thousand nine hundred and five. In fact, IT wasn't even understand. I should have more credit to mancos I in nineteen thousand seven. So einen stein in nineteen thousand five figured out that you could get rid of the either the idea of a rest frame for the universe and all the equations of physics would make sense, with the speed of light being a maximum.

But then IT was mankowski, who used to be einsteinian professor in one nine hundred and seven, who realized the most elegant way of thinking about this idea of instead, was to blend space in time together, into space time, to really imagine that there is no hard and fast division of the four dimension al world in which we live into space and time separately. Einst stein was at first dismissive of this. He thought I was just like, oh, the mathematicians are over formalizing again.

But then he later realized that if spacetime is a thing, you can have properties, and in particular can have a geometry, he can be curve from place to place. And that was what let him solve the problem of gravity. He was always been, he had previously been trying to fit in what we knew about gravity, from newtonian mechanics, the inverse square law of gravity, to his new relatives, tic theory.

IT didn't work. So the final leap was to say, gravity is the curvy of spacetime. And that statement is basically general relativity .

and the tension. Al of manaos. There's a mathematician, yes. So the attention between physics and mathematics, in fact, in your lecture about this equation, one of them, you say that einstein is a Better physicist. He gets credit for.

I know that's hard. It's a little bit of a joke there, right? Yeah because we all give lines line a lot of credit.

But then we also partly based on fact, with partly to make ourselves feel Better, tell ourselves a story about how later in life einstein in couldn't keep up. Uh, there were Younger people doing quantum mechanics and in quantum field theory, in particle physics. And he was just sort of unable to really philosophically get over his objections to that.

And I think that that story about the latter part is completely wrong, like almost one hundred eighty degrees wrong. I think that einstein understood quana mechanics as well as anyone, at least up to the one thousand thousand and thirties. I think that his physical ical objections to IT are correct.

So you should actually been taken much more seriously about that. And what he did, what he achieved in trying to think these problems through is to really basically understand the idea quantum entanglement ment, which is kind of important these days when he comes to understanding economic mics. Now it's true that the forties and fifties, he pled his efforts in hopes for unifying electricity and magazines with gravity.

That didn't really work out very well. All of us, you try things that don't work out. I don't hold that against him. But in terms of I Q points, in terms of trying to be a clear thinking physicist, he was really, really great.

What is greatness look like for a physicist? So how difficult is IT to take the leap from special relativity of general relativity? How difficult is IT to imagine that to consider space time together and to imagine that there's a curvy to this whole thing? Yeah that's a great question.

Um I think that if you want to make the case for einstein in's greatness, which is not hard to do, there's two things you point at. One is in one thousand nine to five, his famous miracle year, he writes three different papers on three wildly different subjects, all of which or would make you famous just for writing that one paper um special relativity.

One of them Browne in motion is another one which is just, you know, the little vibrations of tiny, little little duck CT in the air. But who cares about that? What matters is improves the existence of atoms, he explains, grounding emotion by imaging their molecules, the air, and deriving their properties.

brilliant. And then he basically starts the world on the road to quantum mechanics with his paper, on which, again, is given a boring label, the photo electric effect. What IT really was, as he invented photons, he showed that light should be thought of as particle as well as waves.

And in all three of those very different things in one year. Okay, but the other thing that gets him genius status, this is, like you say, general relativity. So this takes ten years from nineteen thousand five thousand nine hundred and fifteen.

He wasn't only doing general relativity. He was working on other things. He wrote, invented refrigerator. He did various interesting things, and he wasn't leaving. The only one working on the problem, there are other people who suggested relativist theories of gravity, but he really applied himself to IT. And I think is your question suggests the solution was not a matter of turning a crank.

That was something fundamentally creative in his own telling of the story, his greatest moment, his happiest moment, was when he realized that if the way that we would modern and say, in monitoring, if you were in a rocket ship accelerating at one g at one h acceleration to the gravity, if the rocker's were very quiet, you would be able to know the difference between being in a rocket ship and being on the surface of the earth. Gravity is sort of not detectives, or least not distinguishable from acceleration. So number one, that's a pretty clever thing to think.

The number two of you were, I had had that thought, we would have gone how we're pretty clever. He's reasons from there to say, okay, gravity is not detectable. Then IT can be like an ordinary force, right? The election on magnetic force is detectable.

We can put charge particles around positively charged particles. And negatively charged particles respond differently to electric field or to a magnetic field. He realizes that what his thought experiment showed, or he suggested, is that gravity isn't like that.

Everything responds in the same way to gravity. How could that be the case? And then this other leap he makes this, oh, this is the curvature of space time, right? It's a feature of spacetime, is not a force on top of IT.

And the feature that IT is, is curvature. And then finally, he says, okay, clearly, i'm gonna the mathematical tools necessary to describe carpet. I don't know them, so I will learn them. And they didn't have books or A I A helpers back in those days. He had a sit down and read the math papers, and he told himself differential geometry and invented general relativity.

What about the step of including time as just another dimension? So combining space and time that a simple mathematical leap as monkey suggested.

it's certainly not simple actually. Um it's a it's a profoundness like that's why I said I think we should give when calls you more credit than we do. You know he's the one who really put the finishing touches on special relativity.

Again, many people had talked about how things change when you move close to the speed of light, uh, what maxwell s equations of electro magical sm predict and so forth, what their symes's are. So people like laren's face gerold and punched a story that goes there. And in the usual telling einstein where to puts the capstone on IT, he's the one who says all this makes much more sense if they're just is no either IT is undetectable.

We don't know how fast everything's relative thus the name relativity. But he didn't take the actual final step, which was to realize that the underlying structure that he had invented his best thought of as unifying space in time together. I honestly don't know what was going through in cosme's mind when he thought that that i'm not sure if he was so mathematically a debt that he was just clear to him or he was really strugling IT and he try an error for a while. I'm not .

sure my deal for him, for france that I visualized the dimension al space, try to play with. The idea of time is just another dimension.

Oh yeah, all the time. I mean, we of course, make our lives easy by ignoring two of the dimensions of space. So instead of four dimensional space time, we just draw pictures of one dimensional space.

One dimension of time was so called space time diagram. But, you know, I mean, maybe this is lucky underneath to your question, but even the best physicists will draw you A A vertical access and a arizon axis logo space time. But deep down, that's wrong because you're sort of preferring one direction of space and one direction of time.

And it's really the whole two dimensional thing, that is space, time. The more legitimate thing to draw on that picture, our rays of light, our light comes from every point. There is a fixed direction at which the speed of light would represent. And that is actually inherent in the structure, the division in this space and time. Something is easy for us human beings.

What is the difference in gene space and time? From the perspective of general relativity?

It's the difference in x and y. When you draw, x is on a piece of paper.

really no difference.

There is almost no difference. There's one difference that is kind of important, which is the following. If you have a curve in space, I will draw IT orizondo ally because that's usually what we do in space time diagrams.

You have a carbon space. You've heard the model before that the shortest distance between two points in the raight line, if you have a curve in time, which is, by the way, literally all of our lives, right? We all evolve in time.

So you can start with one event in space time and in another event in space time. What manossi points out is that the time you measure along your trajectory in the universe is precisely analogous to the distance you to travel on a curve through space. And by precisely, I mean, IT is also true that the actual distance you travel through depends on your path, right, and go a straight line towards distance in curry, lying to be longer. The time you measure in space time, the literal time that takes off in your clock also depends on your path, but IT depends on on the other way, so that the longest time between two points is a straight line. And if you zig back and forth in space time, you take a less and less time to go from point a to point B.

How do you make sense of that the difference between the observed reality and the objective reality underneath IT or is objective reality of silly notion given general relatives .

a huge body object of reality? I think the object reality object fan is real um but I do think that people kind of are little overly casual about the relationship between what we observe an objective reality in the following sense. Of course, in order to explain the world, our starting point and our ending point is our observations, our experimental input, the phenomena we experience and see around us in the world. But in between, there is a theory, there's a mathematical formalization of our ideas about what is going on. And if a theory fits the data and is very simple and makes sense in its own terms, then we say that the theory is right, and that means that we should attribute some reality to the entities, the playing important role in that theory, at least provisionally, until we come up with .

a Better theory on the road. I think a nice way to test the difference between objective reality and the absurd reality is what happens at the at the edge of the horizon of a black hole. So technically, as you get closer to that horizon, time stands still.

Yes, I know IT depends on exactly how careful we are being. So here's A A bunch of things. I think you're correct if you imagine there is a black hole space time.

So like the whole solution inside equation and and you treat you and me as well, we call test particles. So we don't have any gravitation fields ourselves. We just move around in the gravitational fiel. That's obviously approximation. Okay, let's let's imagine that.

And you stand outside the black hole and I fall in, and as i'm falling in and waving to you, you know, i'm going into the black hole, you will see me move more, more slowly. And also the light for me is red shifted so I can look embarrassed because i'm playing the black hole. And there is a limit.

There is a last moment that light will be admitted for me from your perspective forever. okay. Now you don't literally see IT because i'm admitting photons more more slowly, right?

Because from your point of view, so it's not like i'm equally bright. I basically fade from view in that picture. Okay, that's one approximation.

The other proximately is I do have a gravitational field of my own and therefore, as I approached the black hole, the black hole doesn't just sit there and let me pass through IT kind of moves out to eat me up because its next energy mass is going to be mine plus hits. But roughly speaking, yes, I think so. I don't like to go to the drastic extremes because that's what the approximate break down. But if you see something falling into black hole, you see its clock ticking more.

more slowly.

How do we know? IT felin, we don't. I mean, how would we? Because it's always possible that writing last minute IT had a change of heart and starts accelerating away, right?

If you don't see IT passing, you don't know. And let's point out that the smartest st. Einstein was he d never figured out black holes and he could have. It's kind of embarrassing that took decades for people thinking about general relativity to understand that there are such thing as black holes, because basically nine sign comes up with general relativity in one thousand and fifteen, two years later, short, chilled.

Carl source ld derives the solution to einstein in equation that represents S A black hole, the shortness eld solution, no one recognized for what I was until the fifties, David thinks. And other people. And that's just, you know, one of these examples of physicists not being as clever as they should have been.

What I see, singular, that's the kind of the edge, the theory, the limit. So it's understandable, is difficult to imagine the limit of things.

IT is absolutely hard to imagine. And black hole is very different to many ways from were used to. On the other hand, I mean, I mean, the real reason, of course, is that between one thousand nine hundred and fifteen, one thousand nine hundred and fifty five, there's much of other things that are really interesting going on in physics, all particle physics, in point peel theory. So many of the greatest minds were focused on that. But still, if the universe hands you a solution to general relativity in terms of curves, space, time, and it's kind of mysterious certain features of IT, I would put some effort .

and trying to figure IT out. So how does the black hole work? Put yourself in the shoes line stine, and take general relativity to a natural conclusion about these .

massive things. It's best to think of a black hole is not an object so much as a region of space time, okay? It's a region with the property.

At least in classical general relativity, quantum changes s makes everything harder. But I imagine we're being classical for the moment. It's a region space time with the property that if you enter, you can't leave.

Literally the equivalent of escaping a black hole would be moving fast in the speed of light. They're both precisely, equally difficult. You have to move fast, would like to escape from the black hole. So once you're in, that's fine. You know in principle, uh, you don't even notice when you cross the eventual zing as we call the events izon, is that point of no return where once you're inside, you can leave. But meanwhile, the space time is sort of collapsing around you a to ultimately a singularity in your future, which means that the gravitational forces are so strong they Carry your body apart um and you will die in the finite count of time. The time IT takes if the if the black hole is about the mass of the sun to go from the eventual ized to the singularity takes about one million of a second.

And what happens if you found to the black hole, if you think of an object as a information that information has destroyed?

Well, you raised a crucially difficult point. So that's why I keep needing to distinguish tween black holes according to einstein theory, general relativity, which is book one of spacetime and geometry, which is perfectly classical. And then come the one thousand nine hundred and seventies, we start asking about quantum changed s and what happens in quantum changes s.

According to classical general relativity, the information that makes up you when you fall into the black hole is lost to the outside world, is there is inside the black hole. But we can get IT anymore. In the thousand nine hundred seventies, even hawking comes along and points out the holds radiate.

They give off photons and other particles to the universe around them, and as they radiate, they lose mass, and eventually they evaporate. They disappear. So once that happens, I can no longer say the information about you or a book that I threw.

The black hole, or whatever is still there, is hidden behind the black holes. The black holes gone away. So either that information is destroyed, like you said, or IT is somehow transferred to the radiation that is coming out to the hawking radiation.

The large majority of people who think about this believe that the information is somehow transferred to the radiation and information is conserved. That is the a feature both of general relativity ity by itself and and we can expect itself. So you put them together.

That should still be a future. We don't know that for sure. There are people who have got IT Steven hawking for a long time, but that's what most people think. And so what we're trying to do now, in a topic which is generated many, many hundreds of papers called the black hole information loss puzzle, is figure out how to get the information from you or the book into the radiation that is escaping the black hole.

Is there any way to observe hawking radiation to a degree where you can start getting insight? Or is this all just in the space of theory right now?

Right now, we are nowhere close to observing hawking radiation. Here is the sad fact, the larger the black hole is, the lowest temperature is. So a small black hole, like a microscopic ly small black hole, might be very visible to given off light.

But something like the black hole center of our galaxy, three million times the master of the sun, or something like that, vegetarians, a star, uh, that is so cold and low temperature that its radiation will never be observed able. Black holes are hard to make. We don't have any nearby ying. The ones we have out there in the universe are very, very faint. So there's no immediately hope for detecting .

talking is allegedly, we don't have any nearby.

As far as we know.

we don't have any nearby. Could tiny be hard to detect somewhere at the edge of the sort may be .

so you don't want them to be too tiny or they are exploding, right? They're very bright and then they'll be visible. But there is an absolutely regime where black holds are large enough not to be visible because the larger ones are venture, right? Not giving of radiation, but small enough to do up and detected through the reputational effect.

And psychologically, just emotionally, hoti feel about black holes.

They scary. I love, I love like holes. But the universe weirdly makes IT hard to make a black hole, right? Because you really need to squeak an enormous amount of matter energy into a very, very small region of space.

So we know how to make Stellar black holes. A supermassive star can collapse to make a black hole. We know we also have these supermassive black holes, the center of galaxies, where a little unclear where they came from, I mean, maybe still black holes that got together, uh, and combined.

But that, you know, one of the exciting things about new data from the game's web space telescope is that quite large black holes seem to exist relatively early in history of universe. So IT was already difficult. Figure out where they came from now is the new tough puzzle.

So these supermassive black holes are formed and somewhere early on in the universe, I mean, that's the future, not a bug, great. That we don't have too many of them, others SE who would have a uh the time or the space to form the the little pockets of complexity that will call humans.

I think that's fair. Yeah, it's always interesting. When something is difficult, what happens anyway? right? I mean, the probability of making a black hole could have been zero, IT could have been one. But is this interesting number between which is kind of fun?

Are there are more intelligent aliens, civilians than there are supermassive black holes?

Yeah, I have no idea. But I think what your intuition is, right, that IT would be easy for there to be lots of civilization. And then we would have noticed them already, and we haven't. So absolutely, the simplest explanation for why we haven't is .

that they are not there. Yeah, I just think it's so easy to make them now. So there must be anything as a simple explanation.

But also easy, easy to make life, or you Carry us life, or multiple .

la life IT. Seems like life finds way intelligent an citizen. sure. Maybe there is somewhere along that chain a really, really hard leap. But once you start life, once you get the original life, IT seems like life just finds away everywhere, in every condition. This figures IT out.

I mean, I get I get exactly what you're thinking. And I think it's a perfectly reasonable attitude to have before you confront the data. I would not have expected her to be special in anyway. I would have expected there to be a plenty of very noticeable, extra transfuse civilizations out there. But even if life finds away, even if we buy everything you say, how long does IT take for life to find a way? What if IT typically takes one hundred billion years, then we'd be alone.

So the time thing, so do you really leaders most likely ader know aliza out there. I just I I believe that yeah, none of them. And there's another explanation.

While we can see them, I don't believe that very strongly. Look, i'm not going to a place. A lot of bets here. I would not i'm both pretty up in the air about whether not life itself is all over the place as possible.

We know when we visit other world's other solar systems, there's very tiny microscopic life ubiquitous, but none of IT has reached some complex form. It's also possible to just there isn't tiny. It's also possible that there are chAllenge ence civilizations that are Better things to do than knock on our doors. So I think we should be very humble about these things we know so little about.

And it's also possible there's a great filter where there's something fundamental about, uh, once the civilization developed complex enough technology, that technologies is more statistically likely to to destroy everybody versus to continue being creative.

That is absolutely possible. I'm actually putting less created on that one just because you need to happen every single time, right? If even one.

This respect of funny point in john fenya points that you don't need to send the aliens around the galaxy. You can build self reproducing probes and send them around the galaxy. And you might think, well, the galaxy is very big.

It's really not. It's some tens of thousands of light years across and billions of years old. So you don't need to move at a high fraction the speed of light to fill the galaxy.

So if you were in an intellect, aliens, civilization, the dictator of one, you would just send out a lot of probe sofa application.

hundred percent, and just spread out. yes. And what you should do this is, so you want the optimistic spin. Here's the optimistic s pin.

People looking for intelligent life elsewhere often tune in with their radio telescopes, right? At least we did before every seba was decommissioned. That's IT not a very promising way to find intelligent life elsewhere.

Because why in the world with a super intelligent alien and civilization waste all of his energy by beaming ing and ranting directions into the sky? For one thing, IT just passes you buy, right? So if if we are here on earth, we've only been listening to radio ways for a hundred couple hundred years.

okay? So if the intelligent aliens civilization exists for a billion years, they have to pinpoint exactly the right time to send us this signal. IT is much, much more efficient to send robes and the park to go to the other solar systems.

Just sit there and wait for an intelligence civilians to raise in that solar system. This is kind of the two thousand and one. I put this this right. I would, I would be less surprised to find, uh, sort of quiet and alien artifact in our solar system. Then I would to catch a radio signal from an intelligence civilization.

So here, soccer for in persons conversations versus remote.

I just wanted integrate over time. A probe can just sit there and wait, where, as a radio way goes right by.

how hard is IT for nAiling civilian, again, near the dictor of one, to figure out a probe that is most likely define a common language with .

whatever IT finds. Would I be .

like the elected leader, a elected leader, a democratic aliens, civic?

I think we would figure that language thing pretty quickly. I mean, maybe not as quickly as we do when different human tribes find each other, because obviously lot of commonalities in humanity. But there is logic in math, and there is the physical world. You can point to a rock and go rock, right? I don't think you'd take that loan. Um I know that arrival uh the movie, uh, based on a ted jank story, suggested that the way that aliens communicate is going to be fundamentally different but also they had recognition, things I don't believe in so I think that if we actually find alien, that will not be our long term problem.

So there's a first one of the place you're familiar with, the sanity. And they approach the question of complexity, many different ways, and ask the question of many different ways of what is life thinking broadly. So you would be able to find IT you think you show up approach shows up to a planet, will see a thing. And do I get that's that's a living thing?

Well, again, if it's intelligent and technologically advanced, the the more short term question of if we get know some spectrum scope c data from an exoplanet. So we know a little bit about what is in an atmosphere, how can we judge whether not that atmosphere is giving us a signature of life existing? That's a very hard question the people are debating about. And in one very simple minded, but perhaps um interesting approach, aches to say small molecules don't tell you anything because even if life could make them, something else could also make them but long molecules that the kind of thing that life would produce.

So signs of complexity, I don't know. I just have this nervous feeling that we won't be able to detect, show up to plan. They will bunch of liquid on IT with I dip, we take a swimmin the liquid and we won't be able to see the intelligence in the but whether whether that intelligence looks like something like you know answers, we'll see movement, perhaps strange movement, but we won't be able to um see the intelligence in IT or communicate with IT. I guess if we have nearly in the amount of time to play with different ideas, what might be able to.

you know, I think I mean, in favor of this kind of humilities intellectual humility that we won't know, because we should be prepared for surprises. But I do always keep coming back to the idea that we all live in the same physical universe. And if, well, let let's put this way, the development of our intelligence has certainly been connected to our ability to manipulate the physical world around us.

And so I would guess without one hundred percent reasons, by any means. But my guess would be that any advanced kind of life would also have that capability. You know, both dolphins and octopuses are potential counter examples to that. But I think in the details, there would be enough similarities that we recognize IT.

I don't know how we got on this topic, but I think I was from supremacy black holes. So if we return to black holes and talk the the holographic principle more broadly, you have a recent paper on the topic, even thinking about the topic in terms of rigorous research perspective, and just that as a popular book writer. So what is the holographic principal? Well.

IT goes back to this question that we were talking about with the information. And how IT gets out in quantum mechanics certainly are ugly even before quantity changes s comes along. In classical statistical mechanics, there's a relationship between information and entropy.

Entropy is my favorite to talk about. I written books about what to read books about. So hawking tells us that black holes have entr y and is a finite amount of entropy is not an infinite amount.

But the belief is. And now we're already getting quite speculative. The belief is that the entropy of a black hole is the largest amount of entropy that you can have in the region of space time.

It's of the most densely packed the entrepreneurs. And what that means is there is what of a maximum t of information that you can fit into that region of space and you call IT a black hole. And interestingly, might expect to have a box. And i'm going to put information in IT.

And I don't tell you how i'm going to put the information in, but I ask, how is the information I can put in scale with the size of the box? You might think, well, IT goes as the volume of the box because the information takes up some volume and I can only fit in a certain amount. And that is what you might guess for the black hole.

But it's not what the answer is. The answer is that the maximum information, as reflected in the black hole entropy scales as the area of the black holes, eventually ized not the volume inside. So people thought about that in both deep and superficial ways for a long time.

And they proposed what we now call the holographic principle, that the way that space time in quantum m gravity convey information or hold information is not different bits or cubits for quantum information at every point in space time IT is something holographic, which means that sort of embedded in or located in, or can be thought of as pertaining to one dimensionless of the three dimensions of space that we live in. So in the case of black hole, the ever horizon is two dimensional, embedded the three dimensional universe. And the holographic principal would say all of the information contained in the black hole can be thought of us living on the eventual zing rather than in the interior of the black hole.

I need to say one more thing about which is that this was an idea. What the idea just told you was the original holographic principle put forward by people like ja tough and lenders huskin, super famous physicists, lenders can was on my podcast, didn't gave a great talk, is very, very good to explaining these things. My escape by my life. That's right. yes.

And you don't just have physicists done.

I don't I .

love my escape. I'll thank you very much. Curiosity driven.

but any but I trying to get with and a little vague, they were a little handwaving about hoog phy and what that meant, where hoog phy, the idea that information is sort of encoded on a boundary, uh, really came into its own, was with one modesta in the ninety nineties, uh, and the A D S C F T correspondence, which we don't have to get into that in to any detail, but it's a whole full blown theory of its two different theories. One theory in n dimensions of spacetime without gravity, another theory, an and plus one dimensions of spacetime with gravity, and the ideas that this n dimensional theory is casting a hologram into the end less one dimensional universe to make IT look like IT as gravity. And that pilots phy with adventure and that's that's an enormous source of interest with theoretical .

physicists these days. But how should we picture what impact that has? Uh, the fact that you can store all the information you can think of as all the information that goes into black hole can be stored at the ever horizon yeah I mean.

it's a good question. Um one of the things that quantum field theory indirectly suggests is that there's not that much information in you and me compared to the volume, space, time we take up. As far as quantified theory concerned, you and I are mostly mp space and so we are not information dense, right?

The density of information in us or in a book or A C D or whatever computer RAM is indeed encoded by value like there's different bits located different points in space. But that density of information is super dupper low. So we are just like the speed of lighter, just like the big bang for the information of black hole.

We are far away in our everyday experience from the regime where these questions become relevant. So it's very far away from our intuition. We don't really know how to think about these things. We can do the math, but we don't feel that in our bones.

You can just write off that where stuff happens like to do Better.

but we are trying. I mean, that's why we have a information loss puzzle because we haven't completely solved IT. So here, just one thing to keep in mind, once space time becomes flexible, what IT does according to general relativity, and you have quantum changed s, which has fluctuations and virtual particles and things like that.

The very idea of a location in spacetime becomes a little bit fuzzy, right? Because it's flexible in quantum changes, says you can even put IT down so information can propagate in ways that you might not have expected. And that's easy to say, and it's true, but we haven't yet come up with the right way to talk about IT. That is perfectly rigorous.

but it's crazy how dense with information of black hole is. And then plus, like quite a mechanic, starts to come into place. So you know you almost want to remember size, the kind of interesting computational things .

that are going to the I out. One other thing, information dense, but it's also very, very high entropy. So a black hole is kind of like a very, very, very specific random number, right? IT takes a lot of digits to specify IT, but the digital don't tell you anything. They don't give you anything useful to work on. So IT takes all of information but it's not of a form that we can um learn a lot from.

But hypothetically.

I guess as you mention.

the information might be preserved, the information that goes into a black hole IT doesn't get destroyed. So what what does that mean when the entropy is really high?

Well, the black hole, I said that the black hole is the highest density of information, but there's not the higher amount of information because the black hole can evaporate. And when that evaporates, and people have done the equations for this, when IT evaporate, the entropy that IT turns into was actually higher than the entropy of the black hole buz, which is good because entropy supposed to go up, but it's much more dilute, right, to spread across a huge volume of space time. So in principle, all that you made the black hole out of the information that he took is still there, we think, in that information.

but it's scattered to the four winds. We just talked about the event horizon, a black hot, what's on the inside, what's at the center.

with no once been there.

So come back again.

This is a theoretical prediction. But I i'll say one super crucial feature of the black holes that we know and love, the kind of short child first invented there is a singularity, but it's not at the middle of the black hole remembers space in time, or parts of two different to parts of one unified space time, the location of the singularity. The black hole is not the middle of space, but our future IT is a moment of time.

IT is like a big punch. You know, the big bang was an expansion from a singularity in the past. Big brunch probably doesn't exist, but if I did, IT would be a collapsed to a singularity in the future.

That's what the interiors of black holes are like. You can be fine in the interior, but things are becoming more more crowded, space time is becoming more more warped, and eventually you hit a limit. And that's the singularity .

in your future. And what of what time is like on the inside of a black hole?

Time always ticked by a one second per second. That's all I can never do. Time can tick by differently for different people.

And so you have things like the twin paradox, where two people initially are the same age. One goes off, the people comes back. Now they're not.

You can you and work out that the one who goes out and comes back will be Younger because they did not take the shortest distance path, but locally, as hard as you and your wristwatch are concerned. Time is not funny. Time your, your neurological signals in your brain and your heartbeat and your wrist. Watch whatever is happening to them is happy to all of them at the same time. So time always seems to be ticking along at the same rate.

Well, if you follow your back call and then i'm an observer just watching IT, and then you come out once to evaporates. A million years later, I guess you be exactly the same age.

Have you aged at all? You would be converted into photons. You would not be you anymore, right?

So it's not at all possible that information preserved exactly the .

woman IT depends on you might preserved um it's there in the microscopic configuration of the universe. It's exactly as if I took a regular book, made a paper and I burned IT. The laws of physics say that all the information, the book is still there in the heat and light and ashes. We are never going to get IT yeah a matter of practice, but in principle is still there.

But what about the age of things from the observer perspective? From outside the black hole.

from outside the black hole doesn't matter. Is there inside the black hole?

No, so, but isn't okay. There's no way to escape the black hole, right, except to let .

IT evaporated vapor. But also, you know, by the way, in just in relativity, special relativity, forget about general relativity. It's enormously tempting to say, okay, here's what happening to me right now.

I want to know what's happening far away right now. The whole point relativists to say there's no such thing as right now when you're far away. And that is doubly true for what's inside a black hole. So you're tend to say, well, how fast is their clock ticking or how old are they now not allowed to say that according to relativity .

because the space in time is treated the same. And so that does not even even make sense what what happens the time in the holographic principle.

As far as we know, nothing dramatic happens. Um we're not anywhere close to being confident that we know what's going on here yet. So there are good unanswered questions about whether time is fundamental, whether time is emergent, whether has something do with quantum entanglement, whether time really exist at all. Different theories, different proponents of different things. Um but there's nothing specifically about holography that would make us change .

our opinions about time, whatever they happen to be. But holography is fun that the the question space .

he really time is like so all the .

questions about the time is just almost like separate questions whether it's emerging.

all that yeah I mean that might be a reflection of ignorance right now. But yes.

if we figure out a lot, you know, millions of years of the above black holes, how surprised would you be if they travel back in time and told you everything you want to know about black les? How much do .

you think .

there is still to know, and how mind blowing would .

IT be IT does, depending what they would say. You know, I think that there are colleagues of mine who think they were pretty close to figure out how information is out of black holes, how to quantize gravity, things like that. I am more skettles, al, that we are pretty close.

I think there's room for a bunch of surprises to come. So in that sense, I suspect I would be surprised. The biggest, most interesting surprised to me would be if quantum mechanics itself, or somehow superceded by something Better.

As far as I know, there's no empirical evidence based reason to think the quantum chani s is not one hundred percent correct. But IT might not be that always possible. So and there, again, respectable friends of mine who's speculate about IT, so that something I would not the first thing I would want to to know also like .

the black hole would be the most clear illustration. Yeah, that's there's something you would you shop there?

I mean, maybe the point is that black holes are mysterious for various reasons. So yeah, if our best theory of the universe is wrong, that might help explain why.

but he is possible, will find something interesting. Like black holes sometimes create new universe, or black holes are a kind of portal through space, time to another places on like this, like in an our whole conception of what is the fabrics. Space time changes completely because black house is expressed SE type of situation .

yeah you know um that will be less surprising to me that i've already written papers about that we don't have a strong reason to think that the interior black hole is one other universe. But IT is possible and also very possible that that's true for some black holes about others um this is stuff we don't know is easy as questions we can only answer to. The problem is the questions that are easy to ask that we don't know. The answer to you are super hard to answer.

because these objects are very difficult to test, to explore.

Regimes are just very far so, either literally far away in space, but also in energy or mass or time or whatever.

Uh, you a publish a paper on the holograph principle or that involves the holograph and what can you explain the d 调 子弹？

Yeah you know i'm always interested in, since my first published paper, taking these wild, effective ideas and trying to test them against data. And the problem is when you're dealing with wild's specular ideas, they're usually not well defined enough to make a prediction right, like it's kind of yes, I know it's going to happen in some cases. I know it's going to happen in other cases.

So we did the following thing, as i've already mentioned, um the holographic principle, which is meant to reflect the information contained in black holes, seems to be telling us that information there's less information, less stuff they can go on then you might naively expect. So that's upgrade naive vely expect to predict using quantum field theory. Quantum eld theory are best theory of fundamental physics right now.

Unlike this hook phil black hole stuff, quantum field theory entirely local. In every point of space, something can go on, and then you end up all the different points in space. Okay, hold the graphic at all. There's a mismatch between the expectation for what is happening, even an empty space. In connect te theory first is what the photographic principle would predict.

How do you reconcile these two things? So there's one way of doing IT, uh, that have been suggested previously, which is to say that in the quantum field theory, way of talking IT implies there's a whole bunch more states, whole bunch more ways the system could be. They really are and the is and just do a little bit of bath just because there might be some people in the audience who like the math.

If I draw two axes on a two dimensional geometry, like the surface of the table, right? You know that the whole point of IT being too dimensional is I can draw two vectors that are per particular to each other. I can't draw three vectors that are all for particular to each other, right? They need to overlap a little bit. That's true for any numbers of dimensions.

But I can ask, okay, how much do they have to overlap if I try to put more vectors into a vector space than the dimensionality, the vector or space, can I make them almost perpending cut to each other? And the mathematical answer is, as the number of dimensions gets very, very large, you can see a huge extra number of vectors in that are almost particular to each other. So in this case, what we're suggesting is the number of things that can happen in a reason of space is correctly described by holography.

IT is somewhat over counted by quantum field theory, but that's because the quantum field theory states are not exactly perpendicular to each other. I should have mentioned that econometrics states were given by vectors in some huge dimensional vector space, very, very, very, very large dimensions vector space. So maybe the quantified ld theory states are not quite pretentious lar to each other.

If that is true, that's a speculation already. But if that's true, how would you know what is the experimental deviation? And IT would have been completely respectable if we had gone through and made some guesses and found that there is no, no experimental difference.

Because, again, these things are in regimes very, very far away. We stuck our next out. We made some very, very specific guesses as to how this weird overlap of states would show up in the equations of motion for particles like neutrinos.

And then we made predictions on how the neutrinos would behave on the basis of those wild guesses. And then we compared to them with data. And what we found is we're pretty close but haven't yet reached the detectability of the effect that we are predicting.

In other words, well, basically one way of saying what we predict is if a new tree now and there's reasons why is new tree now, we go into if you want, but it's not that interesting. The neutral comes to us from across the universe, from some galaxy very, very far away. There is a probability, as is travelling, that IT will dissolve into other neutrinos because they're not really per particular to each other as Victors as they would or nearly being quantive theory.

And that means that if you look at nutritional coming from far enough away with high enough energies, they should disappear. Like if you see, if you, if you see a whole bunch of nearby nue nose, but then further away, you should see fewer. And there is an experiment called ice cube, which is this amazing testament to the engine of human beings where they go to antarctica and they drill holes, and they put photo detectors on a string a mile deep in these holes, and they basically use all of the ice in a cube. I don't know whether it's a mile or not, but it's like a club or something like that. Some big region that much ice is their detector and they're looking for flashes when a cosmic gray or neutrino, whatever hit, uh, ice molecule, water molecule in the ice.

make flashes in the ice.

they're looking for flashes.

But craze, I mean, what was the detector of that look like?

It's a bunch of strings, many, many, many strings with three hundred six degree photo detectors. yeah. And you that's really cool. It's extremely cool and have an amazing work and they .

find new tinos.

S yes. So the whole point is most cosmic are protons. Because why? Because protons exist and they're massive enough that you can accelerate them to very high energies.

So high energy cosmic is time to be protons. They also tend to hit the earth atmosphere and decaying other particles. So neutrinos, on the other hand, contract through at least usually right to a great extent.

So not just an arctic a, but the whole earth occasionally. And the trend will interact with particle here on earth. And his entry is going through your body all the time from the sun, from the university seta.

And so if you're patient enough and you have a big enough part of the antarctic ice sheet to look at, it's the nice thing about ice is a transparent. So you built yourself. Nature has built you a neutrino detector.

so why does why ice? So is IT just because the low noise and you get to watch this thing and it's .

it's much more dancer than air, but it's transparent.

So have much more dense of high probability than its transparency in an incident in the middle, nowhere. So you can.

so you need, there's not that, right? yeah. So is more stark than anywhere else, right? So anyway, you can go and you get a plot from the s sub experiment.

How many new tree knows there are that they is detected with very high energies. And we predict in our weird little holographic guessing game that there should be a cut off. You should see new tree nodes as you get to hire higher energies, and then they should disappear.

If you look at the data, the data gives out exactly where cut off is. That doesn't mean that our cut off is right. I means they lose the ability to do the experiment exactly where we predict off should be.

Oh boy, okay. Um but why is there a limit? Oh, just because .

there are fewer, fewer high energy neutrals. So there's a spectrum and IT goes down. What we're planting here is a number of nutty nose versus energy is fading away and they just get very.

very few. And you need the high energy nutrition s for the your .

party is little a bigger for higher energy.

And that effect has to do with this almost more ridiculous thing.

And let me just mentioned the name of all of our free dick, who was the post dog who LED this. He deserves the credit for doing this. I was author in a collaborator. I did some work.

but he really gets lying here. Thank you, Oliver. Thank you for pushing this wild size forward. Just speak to that the the matter process of IT. How do you approach asking these big questions and trying to formulate as a is an experiment to that can make a prediction all that kind of what's your process? There's a very .

interesting things that happens once to your theoretical physicist. Once you become trained to your graduate student, you read some papers and whatever. Suddenly you are the world's expert in a really infanta, sively tiny area of knowledge, right? And you know not that much about other areas.

There's an overwhelming temptation to just drill deep, right? Just keep doing basically the thing that you started doing. But maybe the thing you started doing is not the most interesting thing to the world or to you or or whatever.

So you need to separately develop the capability of stepping back and going, okay, now that I can write papers in that area other times for of trained enough in the general procedure. What is the best match between my interests, my abilities and what is actually interesting? And honestly, i've not been very good at that over my career.

Um you know I have my my process traditionally was I was working in this general area of particle physics field, the general relativity Cosmology, and I would sort of try to take things other people talking about and ask myself whether not IT really fit together like my two. So I guess I have three papers that i've ever written that have done super well in terms of getting excited and things like that. One was my first ever paper that I had very little credit for.

That was my advisor in his collaborator. You set that up. The other two were basically my idea. One was um right after we discovered that the universe is accelerating, so one thousand and ninety eight observation show that not only the universe spanning, but is expanding faster and faster.

So that's attributed to either einstein's Cosmos ical constant, or some more complicated form of dark energy, some mysterious thing that fills the universe. And people were throwing around ideas about this dark energy stuff, what could IT be and so forth. Most of the people thrown around these ideas work Cosmologists.

They work on Cosmology. They think about the universe all at once. I know since i'd like to talk to people in different areas, I was sort of more familiar than average with what a respectable working particle physicists would think about these things. And what I immediately thought was, you know, you guys, you're throwing around these theories, these theories are wildly unnatural. They're super finely tuned, like any particle physicists would just be embarrassed to be talking about this.

But rather than just scoff at them, I SAT down and ask myself, okay, is there a respectable version? Is there a way to keep the particle physicists happy, but also make the university celery? And I realized that there is some very specific set of models, that is, that is relatively natural.

And guess what, you can make a new experimental prediction on the basis of those. And so I did that. People were very happy about that.

What was the they would make physicists happy that would make sense of this fragile thing that people called dark energy.

So the fact that dark energy, previous whole universe, and is slowly changing, that should immediately set off alarm balls, because particle physics is a story of length scales and time scales that are generally, guess what, small right particles are small, they vibrate quickly, and you telling, now I have a new field, and its typical rate of change is once every billion years, right? Like that's just not natural.

And indeed, you can formalize that and say, you look, even if you roll down a particle that evolved solely over billions of years, if you let IT interact with other particles at all, that would make IT in and move faster as dynamics would be faster, mass would be higher. Set, set. So is the whole story.

Things need to be. And we'll talk to each other, important field theory. So how do you stop that from happening? And the answer is symmetry.

You can impose a symmetry that protects your new field from talking to any other fields. okay. And this is good for two reasons. Number one, IT can keep the dynamics slow. So if you just you can tell me why IT slow, you just made that up, but at least you can protect IT from speeding up because it's not talking to any other particles.

And the other is that makes the harder to detect um not heavily experiments looking for fifth forces or time changes of fundamental consequence of nature like the charge of the electron. These experiments should have been able to detect these dark energy fields. And I was able to propose a way to stop that from happening.

The detection, the detection yet is what? Because a symmetry could stop IT from interacting with all these other fields, and therefore makes you hard to detect. And just by luck, I realized, because he was actually, based on my first ever paper, there is one looper.

If you impose these symmetries so you protect the dark energy fields from interacting with any other fields, there is one interaction that is still out that you can't rule out. And IT is a very specific interaction between your dark energy field, and photons were very common. And IT has the following effect.

As a photon travels through the dark energy, the photos on has a polarization up, down, left, right, whatever IT happens to be. And as he travels through the dark energy, that photos will rotate ate its polarization. This is called by refrangibility.

And you can kind of run the numbers and say, you know, you can make a very precise predictions is making up this model. But if you want to roughly fit the data, you can predict how much polarization rotation. There should be couple of degrees, okay, not that much.

So that's very hard to detect. People been trying to do IT right now. Literally, we are on the edge of either being able to detected to rule that out using the cosmic microbes ground.

And there is just, you know, truth in advertising. There is a claim on the market that has been detected that is there. Uh, it's not very statistically significant.

If I were too bad, I think would probably go away. It's very hard thing to observe. But maybe as you get Better, Better data, cleaner, cleaner analysis, IT will persist and we will have directly detected the dark energy.

So we just take the attention of dark energy, people will sometimes being bring up dark energy and dark matter as an example, why physicists have lost IT lost their mind, which is going to say that there there is this field. IT permits. Everything is unlike any other field and is invisible.

And IT helps us work out some of the math. How do you respond to that? Let's .

suggestion? Well, two ways. One way is those people would have had to say the same thing when we discovered the planet, because it's exactly an allegiance where we have a very good theory, in that case, newtonian gravity.

In the solar system, we made predictions. The predictions were slightly off. For the motion of the other planets.

You found that you could explain that motion by positing something very simple. One more planet in a very, very particular place. And you went, look forward, there was right. That was the first successful example of finding dark matter.

In the end, the matter of that we can join was dark.

Yeah, there's a difference in dark matter and dark energy, right? Dark matter as far as we are hypothesizing. IT um is a particle of some sort.

It's just a particle that interacts with us very weekly. So we know how much of IT there is. We know more less where IT is.

We know some of these properties. We don't know specifically what IT is, but it's it's not anything fundamentally ally mysterious. It's a particle.

Dark energy is a different story. So dark energy is indeed uniformly spread throughout space and has this very weird property that IT doesn't seem to evolve. As far as we can tell, the same amount of energy in every cube excited meter of space for moment, moment in time.

That's why far and away, the leading candidate for dark energy is einstein's cosmetically constant. The cosmetic consent is strictly constant, one hundred percent constant. The data say IT had Better be ninety eight percent constant or Better.

So one hundred percent content works, right? And it's also very robust. It's just there not doing anything.

IT doesn't interact with any other particles makes perfect sense. Probably the dark energy is the Cosmogonic stant. The dark matter super important.

Emphasize here. You know, IT was hypothesized ed, at first in the seventies and eighties, mostly to explain the rotation of galaxies. Today, the evidence for dark matter is both much Better than that wasn't the one thousand and eighties, and from different sources. IT is mostly from observations of the cosmic background radiation or of large al structure so we have multiple independent lines of evidence, also gravitational lensing and things like that. Many, many pieces of evidence that say the dark matter is there um and and also that say that the effects of dark matter are different then if we modify gravity so that my first answer to the question is dark matter we have a lot of evidence for but the other one is of course we would love IT if IT weren't darkness. Our vested interest is one hundred percent of line with IT being something more cool than interesting than dark matter because dark managers to particle that's the most boring thing .

in the world and it's not uniformly distributed to space dark solution.

Ah so you can even see maps of IT that we have constructed from gravitation lensing.

It's a verifiable set of column of dark matter in the galaxy that explains stuff .

bigger than the galaxy, sadly, like we think that in the galaxy dark matter is lumpy, but it's it's just it's weaker, its effects or weaker. But over the scale of large scale structure and clusters of galaxies and things like that, yes, we can show you where .

the dark matter is to be a super cool explanation for dark matter. That would be interesting, as suppose, to just another particle that sits their clubs.

The super cool explanation would be modifying gravity rather than inventing a new particle. Sadly, that doesn't really work. We've tried, I ve tried.

H that's my third paper that was very successful. I tried to unify dark matter and dark energy together. That was my idea.

That was my aspiration, not even idea. I tried to do IT IT failed. Even before we rote the paper, I realized that my idea did not help.

IT helps. I could possibly explain away the dark energy, but IT would not explain away the dark manner. And so I thought I was not that interesting, actually.

And then two different collaboration of mind set is, anyone thought of this idea like they thought of exactly the same idea completely independently of me? I said, well, if three different people found the same idea, maybe he is interesting. And so we rote the paper. And yeah, I was very interesting people.

very interesting. Can you describe this? Be a little bit like he just fascine how much of a thing there is. There are energy and dark matter and we don't quite understand this. So what what was your dive into the expLoring how to unify tive?

So here is what we know about dark matter and dark energy. Um they become important in regimes where gravity is very, very, very weak. That's kind of the opposite from what you would expect if you actually were modifying gravity.

Like there's a rule of firm in quantified the seta. The new effects show up when the effects are strong, right? We we understand weak fields.

We don't understand strong fields. But okay, maybe this is different, right? So what do I mean by when gravis week, the dark energy shows up late in the history of the universe.

Early in the history of the universe, the dark energy is irrelevant. But remember, the density of dark energy stayed constant. The density of matter and radiation go down.

So at early times, the dark energy was completely irrelevant. Compared the matter radiation at late times, that becomes important. That's also when the university dilute and gravitas relatively weak.

Nothing about galaxies. okay? A galaxy is more dense in the middle, less dense in the outside. And there is a phenomenon, gc fact, about galaxies, that in the interior of galaxies, you don't need dark matter.

That's not so surprising because the density of stars and gas is very high there, and the dark matter is just subdominant, but there's generally A A radius inside of which you don't need dark matter to fit the data, outside of which you do need dark matter with the data. So that's again when gravity is weak, right? So I asked myself um of course, we know in field theory new effects to show up when fields are strong, not weak.

But let's throw that out of the window. Can I write down a theory where gravity alters when IT is weak? And we've already said what gravity is. What is gravity is the curator of spacetime.

So there are mathematical quantities that measure the carpet of space time and generally you would say, like I have understanding einstein equation, which I explained to the readers in the book um relates the current ter is space time to matter and energy. The more matter energy, the more current ure. So i'm saying, what if you add a new term in there that says the less matter energy, the more curvy? No reason to do that except to fit the data, right? So I tried to unify the need for dark .

matter and the need for a super .

right to be the best. It'll be great.

but work IT would be a really interesting. Gravity is some funky. There's not much of IT like, almost like at the edge of IT.

No exact the hope.

But great thing about .

physics is there are equations, right? I mean, you come up with the words and you can wave your hands, but then you got to write down the equations. And I did, and I figured out that I could help with the dark energy, the celebration. The university doesn't help with dark matter at all.

Yeah, it's just success. The scale of galaxies and scale of solar systems, the physical is kind of boring.

Yeah, he does. I agree again, that's why IT is a little bit. I tear my hair out when people who are not physicists think accused physicists, like you say, of what of losing the plot because they need dark matter and dark energy.

I don't want dark matter and dark energy. I want something much cooler than that. I ve tried, but you got to listen to the equations. Enter the data.

You mention three papers, your first ever, your first awesome paper ever. In your second awesome paper ever, of course there are many papers, so you you're being very harsh and the others .

but well by the way, is not awesome ness. This is impacted right? There is no correlation between awesome is an impact t right? Some my best papers fell without a stone before um the first paper was called limits another rest and parody violating modification of electro magnetics or electrode namic s so we figured out a violate Lauren and variants which is the symmetry I underlying relativity and.

The important thing is we figured out a way to do IT that didn't violate anything else and was experimentally testable. So people love that. Uh, the second paper was called quinta ins and the rest of the world. So qantas is is this dynamically energy field? The rest of the world is because I was talking about how the quinta infill would interact with other particles in fields and how to avoid the interactions you don't want. And the third paper was called, um is cosmic speed up due to gravitational physics something like that? So you see the common theme i'm taking, you know what we know the standard model particle physics general tivy tweak them in some way and then trying to fit the data .

and trying to make IT. So it's experimental about a yes.

that's right. That's the goal.

You wrote the book, something deeply hidden on the mysteries, economic ics, and a new book coming out soon, part of the biggest ideas in the universe series we mentioned called quanta and fields. So that's focusing equal mechanics. Big question, first biggest ideas and universe, what you is most beautiful or perhaps most mysterious about quality mics? Chani s is a harder one.

You know, I wrote a textbook on general relativity, and I sorted IT by saying, gene, relative of these most beautiful physical theory ever invented, I will stand by that. IT is less fundamental than quantum mechanics. But quantum channels is a little more mysterious.

So it's it's a little bit luddy right now. You know, if you think about how we teach quantum mechanics toward students, the copenhagen interpretation, it's a got awful mess like no one's achieve that of being very beautiful. I'm affair of the many world's interpretation of qual mechanics and that is very beautiful in the sense that fewer ingredients, just one equation, and I could cover everything in the world.

Um IT depends with me by beauty. But I think that the answered to your question is coomes can start with extraordinary or steer tiny ingredients and in principle, lead to the world, right? Uh, that, bogles, my mind, is a much more comprehensive general activities about gravity that's great and is about everything and seems to be up to the task. And so I don't know what is that beauty or not, but it's certainly .

impressed substance for the theory, the predicted power, the theory and the fact the theory describes tiny things creating everything we see around us.

It's a bonist theory in classical mechanics, and a particle here, particle there. I describe them separately. I can tell you what this particle doing with that particle doing in one we can, we have entanglement, right, as einstein point out to us, in thousand and thirty five.

And what that means is there is a single state for these two particles. There's not one state for this particle, one state for the other particle. And indeed, there is a single state for the whole universe, called the way function, the universe, if you want to call at that. And IT obeys one equation. And is our job then to sort to chop IT up, to carve IT up, to figure out how get tables and chairs and things like .

that out of IT? You mention the many world's interpretation, and IT is, in fact beautiful, but it's one a year more controversial things you stand behind. Yeah, you've probably got a .

bunch of flag for IT.

Well, can you first explain IT? And they may be speak to the flag.

You may have got, know, the classic experiment to explain quana mechanics to people is called the stern gerlach experiment. You're measuring the span of a particle OK and econometrics. The spin is, you know, is just the spin as the rate of which something is rotating around in in a very downer sense.

The difference being is that it's so for something like a single electron or a single news drawn is either spinning clockwise or counterclockwise the only two lisper. This way, the only two measurement outcomes you will ever get, there's no it's spinning faster or slower as he is spinning one direction of the other. That's two choices.

According to the rules of quantum mechanics, I can set up an electron, let's say, in a state where IT is neither purely clockwise or counterclockwise, but a superposition of both. And that's not just because we don't know the answer, is because IT truly is both until we measured. And then when we measured, we see one of the other.

So this is the fundamental mystery, equality of mechanic. Is that how we describe the system when we're not looking at is different from what we see when we look at IT. So we teach our students in the copenhagen of thinking is that the act of measuring the spin of the electron causes a radical change in the physical state, is spontaneously collapses from being a superposition of clockwise and counterclockwise to being one or the other.

And you can tell me the probability that that happens, but that's all you can tell me. And I can't be very special when that happens. What caused that to happen? Why is happening? None of that.

That's all called the measurement problem of quantum channels. So many words just says, look, I just told you a minute ago that there's only one way function for the whole universe and that means that you can take too seriously just describing the electron. You have to include everything else in the universe in particular.

You clearly have to interact with the electron in order to measure IT. So whatever is interacting with the electron should be included in the way function that you're describing. And look, maybe it's just you maybe your eyeballs are able to perceive IT, but okay, i'm going to include you in the wave function.

And if you do, that must be since you have a very sophisticated listenership, i'll be a little bit more careful than average. What does IT mean to measure the spin of the electron? We don't need to go into details, but we want the following thing to be true. If the electron were in a state that was one hundred percent spinning clockwise, then we want the measurement to tell us that was spinning clockwise.

We want your brain to go, yes, the electron was spinning clockwise, right? Likewise, if there was one hundred percent counter clockwise, we want to to see that to measure, that the rules of quantum mechanics, the shorting your equation of quantum mechanics, is one hundred percent clear that if you want to measure IT clockwise when it's clockwise, and measure counterclockwise, when is counterclockwise SE? Then when IT starts out in a superposition, what will happen is that you in the electron will entangle with each other.

And by that I mean that the city of the universe evolves into part, saying the electron was inning clockwise. And I saw a clock. And part of the state is it's a superposition with the part that says the electron was spending counterclockwise.

And I saw a counterclockwise. Everyone agrees with this entirely uncontroversial straighforward consequences, the shorting your equation and then neels poor would say. And then part of that way function disappears.

And we're in the other part, and you can predict party will be only the probability. Whoever IT, who was a graduate to the one thousand and fifties who was thinking about this, says, I have a Better idea. Part away function does not magically disappear.

IT stays there. The reason why that idea averts idea, that the whole way function always sticks around and just obey the finding equation was not thought of years before is because not evenly. You look at IT, you go, okay, this is predicting that I will be in a superposition, but I will be in a superposition of having seen the electron b clock wise and having seen A B counter calise.

No experimenter has ever felt like they were in a superposition. You always see an outcome, okay, ever. It's movie, which was kind of genius, was to say, the problem is not the shorting equation.

The problem is you have been identified yourself in the shorting equation. You've said, oh, look, there's a person who saw counter clockwise. There's a person who saw clock wise.

I should be that superposition of both and ever says, no, no, you're not because the part of the wave function in which the spin was clockwise once that exists IT is completely unaffected by the part of the way function that s says the spin was counterclockwise. They are apart from each other. They are uncontacted.

They have no influence. What happens in one part has no influence on the other part. So effort says the simple resolution is to identify yourself as either the one who saw spin clockwise or the one who saw spin counter clock wise, there are now two people. Once you've done that experiment, the shorting equation doesn't have to be messed with. All you would have to do is locate yourself correctly in the way function that many worlds.

the number of words is very, very, very, very big. Where are those world's fit? Where they go?

The short answer is the words don't exist in space. Space exists separately in each world. So I mean, there's a technically answered to your question, which is hell, but space, the space of all possible economic ical states.

But physically, we want to put these words somewhere. That's just a wrong intuition that we have. There is no such thing as the physical spatial location of the worlds, because spaces inside the worlds.

One of the properties of this interpretation is that you can't travel from one world to the other. That's right. Which kind makes you feel that they're existing separately?

They are existing separately.

And simple tane ously simulator .

ously .

out locations in space without locations in space. How is IT possible to visualize them existing without a location in space?

The real answer, that the honest answer is the equations predict.

Yeah, if you can visualize .

IT so much worse for you, the equations are Crystal al clear about what they're predicting.

Is there way to get to the closer to understanding and visualizing the warehouse the implications of this?

You know, I don't think that hard. Wasn't those that hard for me? You know, I don't mind the idea that when I make an equal mechanical measurement, there is later on in the universe, multiple descendants of my present self who got different answers for that measured, I can interact with them.

Um hilbert space, the baseball quantum way functions was always big enough to include all of them. I'm gonna a worry about the parts of the universe I can observe. So let's put this way.

Many world comes about by taking the shortening er equation seriously. The shortener equation was invented to fit the data, to fit the spectrum of different atoms in different emission and absorption experiments. And it's perfectly legitimate to say, well, okay, you're taking the routing equation.

You're extrapolated, you're trusting IT believing IT beyond what we can observe. I don't want to do that, right. That's perfect, legit except okay, then what do you believe come up with a Better theory? You're saying you don't believe the short of your equation. Tell me, the equation that you believe in turns out, and people done that turns out, is super hard to do that in a legitimate way that fits the data .

and many worlds is a really clean.

absolutely the most all, steer clean, no extra baggage theory of one of mechanics.

So if. IT, in fact, is correct. Isn't the wear the weird thing of anything we know?

yes. In fact, they put this way. The single best reason in my mind, to be skeptical about many worlds is not because IT doesn't make sense or IT doesn't fit the data or I don't know where the world are going or whatever.

It's because to make that extrapolation to take seriously the equation that we know is correct, other regimes requires new philosophy, requires a new way of thinking about identity, about probability, about prediction, a whole bunch of things. It's work to do that philosophy. And i've been doing IT and others have done IT.

I think it's very, very dull. But it's not straight forward. It's not a simple extrapolation from we already know it's a grand extrapolating very far away.

And if you just wanted to be sort of methodologically conservative and say that's a step too far, I don't want to buy IT. I'm sympathetic to that. I think that you're just wiping out. I think that you should have more courage. But I I get the .

impulse and there is underlined world's an area of time where if you rewind back, there's going to be one initial state.

That's right. All of quantum, all different versions, require a kind of arrow of time. You might be different in every kind, but the quantum measurement process is irreversible. You can measure something that collapses. You can call backwards if someone tells you the outcome.

If I say i've measured electron, it's been as clockwise and they say, what was IT before I measured IT? You know there was some part of IT that was clockwise, but you don't know how much, right? And many world is no different. But the nice thing is that the kind of error of time you need in many worlds is exactly the kind of of time you need anyway for entropy and thermal nomics. And so far, you need a simple low entropy initial state.

That's what you need in both cases. So if you actually look at under many worlds into the entire history, the universe crack me from wrong. But he looks very deterministic. Yes, in each moment, does the moment contained the memory of the entire history of universe to you? Does the moment contained the memory of everything .

that proceeded IT as far as we know? So according to many worlds, the way function of the universe, all the branches of the universal ones, all the world, does contain all the information. Calling the memory is a little bit dangerous.

This is not the same kind of memory that uni have in our brains because our memories rely on the arrow of time and the whole point of the shortening their equation, or newton s laws, as they don't have an arrow of time built in, they're reversible. The state of the universe not only remembers where he came from, but also determines where is going to go. In a way that our memories don't do that.

but our memories, we can do replay. Can you do this weekend?

But the act of forming of memory increases the entropy of the universe. IT is an universal process also, right? You can walk on a beach and leave your footprints there. That's a record of your passing. Uh, IT will eventually be based by the every increasing entropy of the universe.

But, but you can imperfectly replay IT. Yes, can we return travel back in time? And perfectly.

oh, depends on the level of precision. You're trying to ask that question. You know, the universe contains the information about where the universe was, but you and I don't. To wear nowhere .

close is what computationally very costly to try to consult the universe.

Well, IT depends on, again, exactly we are asking. Like there are some simple questions like what was the temperature of the universe thirty seconds after for the big bang? We can answer that, right? That's kind of amazing, that we can answer that to pretty high precision. But if you want know where every adam was, the no.

what do you is the big bang? why? Why did IT? why? Why did that .

happen with no idea? I think that that's a super important question that I can imagine making progress on. But right now, i'm more less maximum uncertain about what the answer is.

Think that calls .

will help no potente that much um quantum gravity will help and maybe black holes will help us figure out quantum gravity. So indirectly yes, but we have a situation where general relativity, einstein's theory unambiguously predicts there was a singularity in the past. There was a moment of time when the universe had infinite interval, infinite energy, infinite expansion rate the whole bit.

That's a job, a fancy way of saying the theory has broken down. And classical general relativity, not up to the task of what saying what really happened at that moment. So IT is completely possible.

There was, in some sense, a moment of time before which there were no other moments. And that would be the big bang. Even if it's not a classical general relativity kind of thing, even if quantum changes is involved.

Maybe that's what happened. It's also completely possible. There is time before that, space in time, and they evolved into our hot big bang by some procedure that we don't really understand.

And if time and space emergent and the before even starts getting up.

getting real weird, well, I think that if there is the first moment of time that would be very good evidence or that would fit hand in glove with the idea that time is emergent, if time is fundamental and intends to go forever, it's fundamental.

Well, yeah, I mean, the general formulation of these questions, what's outside what's outside of our universe? So in time and in space, I know the part had questions on, I understand .

I thought my life, my life is asking, but but, but some of them, the answer is that's not the right way to think about.

okay, but is impossible to think at all about what's outside our universe is absolutely git .

to ask questions. But you have to be comfortable with the possibility that the answer is there's no such thing as outside our universe. That's absolutely on the table. In fact, that is the simplest, most likely to be correct to answer that we know .

of but is the only thing in the universe that wouldn't have an outside yeah if the universe .

is the totality of everything that would not have an outside .

and so weird to think there's not an outside. We we want there to be. We want there to be out of a crea crea force that LED to this. And outside, like this is our town. And then there's a bigger world, and there's always a bigger world.

And because that is our experience that the world we grew up in, right? The universe doesn't need obey those rules.

said the weird thing .

when I was a kid that used to keeping up at night. Like, what if the universe had not existed.

right? And if you feel like a lot of pressure that this is, if this is the only universe and we're here, one of the few intelligent civilizations, maybe the only one, it's the old series that were the center of everything, you just feel suspicious. That's why many words is kind of exciting to me because I it's humbling in all the right kinds of ways. IT feels like infinity is the way this whole thing runs.

There is one pitfall that i'll just mention because there's a move that is made in these therefore al edges of Cosmology that I think a little bit mistaken, which is to say i'm going to think about the universe on the basis of imagining that I am a typical observer. This is called the principal of typically, or the principle of mediocrity, or even the coptic in principle. Not special about me, i'm just typical in the universe.

But then you draw some conclusions from this. And what you end up realizing is you've been hilariously preventible because by saying i'm a typical in the universe, you're saying typical observes in the universe are like me, and that is completely unjustified by anything. So i'm not telling you what the right way to do IT is. But these kinds of questions that are not quite grounded in experimental verification or falsification, or once you yet to be very careful about that.

me is one of the most interesting questions. IT is a different ways approach. But like, what's outside of this?

How did the best start? How did we get something for nothing? That's always the thing you're sneaking up too. When you're setting all of these questions, you're always need the black house graining up question um what did all this come from? Yeah and I think there's probably an answer able question.

right? No IT doesn't have to be.

So you think there's there could be a turtle that refuses to reveal its identity?

yes. I think that um specifically the question why there something rather than nothing does not have the kind of answer that we would ordinary attribute to why questions. Because typically, why questions are embedded in the universe, and when we answered them, we take advantage of the features of the universe that we know in love. But the universe itself, as far as we know, is not about IT in anything. They are stronger and therefore IT can just be.

do you think is possible this whole places simulated? sure. It's a really interesting dark, twisted video game. The all existing .

in my own podcast, listeners minds cape. Listeners tears me because they know from my A M A episode des, that if you ever start a question by asking, do you think is possible that the answer is going to be yes? That might not be the answer that you care about, but it's possible, sure, as long as you not, you know, adding two even numbers together and getting an add number .

when you say it's possible, there's a mathematically yes. And then there's .

more of like intuitive, paul, reasonable this. I don't think that there's any philosophical knockout objection to the simulation hypothesis. I also think that there is absolutely no reason to take us seriously.

Do you think humans will try to create one? I guess that that's what how I always think about, know I I see what I spent quite a bit of time over the past two years and a lot more recently in virtual worlds, and just am always captivated by the possibility of creating high and high resolution worlds.

And as we'll talk a little bit about artificial intelligence of the the advancement on the sore of front, you can automatically generate those worlds. And the possibility of existing those automatically generate worlds. Pretty exciting, as long as this consistent physics, quana mechanics and general relativity that govern the generation of those worlds. Uh, so IT just seems like humans will, for sure, try to create this. Yeah.

I think they will create Better, Better simulations. I think the fluster David charmers has done what I consider to be a good job of arguing that we should treat things that happen in virtual reality and in simulated realities as just as real as the reality to be experience. I also think that as a practical matter, people who realize how much harder IT is to simulate a realistic world than we lively believe. So this is not a my lifetime kind of .

worry yeah the practical matter of going from a set of a prototypes that's impressive, you think that govern everything? Similar question on this front is in A G I. Yeah, you've said that were very far .

away from A G I. I want to eliminate the phrase A G I.

So basically when you are analyzing large language models and seeing how far they from whatever A G I is and we can talk about different notions of intelligence that we were not as close as uh, some people in in public you are talking about. So what's your intuition behind that?

My intuition is basically that artificial intelligence is different than human intelligence. And so the mistake that is being made by focus on A G I among those who do is a an artificial agent as we can make them now or in the near future, might be way Better than human beings at some things, way worse than human beings that other things. And rather than trying to ask how closes IT to being a human like intelligence, we should appreciated for what its capabilities are. And that will both be more accurate and help us put IT to work and protect us from the dangers Better rather than always anthropy vision IT.

I think the underlying idea there under the definition of making eyes that the capabilities are extremely impressive. That's not a .

precise stage.

What I mean, I then on the line question where the a lot of the debate is home press visit, what are the limits of large language models? Can they really do things like common sense? And in how much do they really understand about the world? Are they just fancy mimic machines? And where do you find that next to the limits of large language models?

I don't think that there are many limits in principle. I not i'm a physical list about consciousness and awareness and things like that. I see no optical to, in principle, building artificial machine that is in distinguish in thought and cognition from a human being.

But we're not trying to do that, right? What a large language model is trying to do is to predict text. That's what he does.

And IT is leveraging the fact that we human beings, for very good evolutionary biology reasons, attribute intentionality and intelligence and agency to things that act like human beings. As I was driving here to get to this podcast space, I was using google maps. Google maps was talking to me, but I wanted to stop to get a cup of coffee.

So I didn't do what google maps told me to do. I went around a block that I didn't like. And so IT gets annoyed, right? IT IT says, like, no, what you do IT doesn't say exactly in this, but you know what I mean? It's like, no, turn left, turn left and you turn right. IT is impossible as a human being not to feel a little bit sad. The google map is getting mad at you. It's not it's not even trying to do, is not the largest language model, is not as no aspirations to intentionally, but we attribute that all the time, then deny the philosopher rote a very influential paper on the intentional stance, the fact that is just the most natural thing in the world for we human beings to attribute more intentionality two artificial things that are really there, which is not to say you can't be really there, but if you are trying to be rational and clear thinking about this, the first step is to recognize our huge bias towards attributing things below the surface to systems that are enable, that are able to add the surface level at human.

So if that huge bias of intentionally ties there in the data, in the human data, in the vast landscape of human data, that A I models, large language models and video models in the future are trained on, don't you think that that intentionality will emerge as fundamental to the behavior of these systems naturally?

Well, I don't think that will happen. Nh, I think you could happen again. I'm not against the the principle, but again, the way that large language models came to be and what they're optimized for is wildly different than the way the human beings came to be and what they're optimized for. So I think we're missing a chance to be much more clear headed about what largest language models are by judging them against human beings again, both in positive ways and negative way. Well.

I I think is to push back on what they're optimize for is different to describe how they are trained versus what they're optimize for. So their train is very trivial way of predicting tax tokens. But you can describe with their optimized foreign the actual task and hand.

This is to construct the world model, meaning in the understanding of the world. And that's where he starts getting closer to what humans are kind of doing. We're just, in the case of large language models, know how the sausage is made and we don't know how it's made for us humans.

But they're not optimize for that. They're optimize .

to sound human. That's the fine tuning. But the actual training is optimize for understanding, creating a compressive representation right of all the stuff that humans have created on the international net. And the hope is that, that gives you a deep understanding of the world .

yeah so that's I think, is a set of hugely interesting questions to be asked about the ways in which large language models actually do represent the world because what is clear is that they're very good at acting human. The open question in my mind is, is the easiest, most efficient, best way to act human to do the same things that human beings do or are there other ways and I think that's an open question.

I just heard to talk by melanie Mitchell and sent of fans to two to an artificial intelligence researcher and he told two stories um about two different papers one that someone else rote and one that her group is following up on and they were modeling a fellow, a fellow, the game with a little rectangle, the board, White and black squares. So the experiment was the following. They fed a neural network, the moves that were being made in the most evolved form, like e five, just means that, okay, you put talking on.

If so, IT gives a long string and does this for millions of games, right? Real, legitimate games. And then he asks the question. The paper asked the question, OK, you've trained IT to tell what will be a legitimate next move from not a legitimate next move.

Did IT in its brain? A little large language model? Brain, I know, you know, of technical large language model, but a deeper learning network did IT come up with a representation of the fell board. Well, how do you know? And so they construct a little probe network that they insert.

And you ask, IT, what is the doing rate this moment, right? And the answer is that the little probe network can ask, you know, what this be legitimate is that is this token White, black or whatever um things that in in practice would amount to its invented to the avella board and IT found that um the probe got the right answer, not one hundred percent of the time, but more than by chance, substantially more than by chance so they said there are some tentative evidence that this neural network has discovered the fl board just out of data, raw data, right? But the melanie group ask the question, okay, you sure that that understanding of the of the fell board wasn't built into your probe and what they found was like elite half of the improvement was built into the probe? You know, not all of IT, right? And look, A A fellow board is way simpler than the world.

So that's why I just I just think it's an open question whether or not the I mean, you will be remarkable either way to learn that large language models that are good at doing what we train them to do are good because they've built the same kind of one of the world that we have in our minds or that they're good despite not having that model either. One of these is an amazing thing. I just think the data are clear on which one is true.

I think I have some of intellectual humidity about the whole thing because I was humbled by several stages in the machine learning development over the past twenty years, and I was just would never have predicted that alums, the way they are trained on the scale of data, their train would be as impressive as they are.

And there that's more intellectual humility, steps in where my intuition would say something like with melanie, you need to be able to have vous of concrete common sense reasoning, symbolic reasoning, type things in a system in order for you to be very intelligent. But here is, am so impressed by what is capable to do. Train on next token prediction. That's I I just my conception of the nature of intelligence is just completely, not completely, but uh, humbled, I should say. Look.

and I think that's perfectly fair. I also um was I was very pleasantly, I was pleasant. You're unpleasantly but actually surprised by the recent rate of progress.

Clearly, some kind of face transition percussion has happened, right? And the improvement has been remarkable, absolutely amazing that I have no arguments with. And that doesn't yet tell me the mechanism by which that improvement happened. Constructing a model much like a human being would have is clearly one possible mechanism. But part of the intellectual humilities to say, maybe there are others .

I was sharing with the sea of anthropic diomed. So behind clown and that company. But a lot of a lot of the air companies are really focused on expanding the scale compute sort. If we assume that A I is not data limited, but is compute limited, you can make the system much more intelligence by using more compute. So let me ask you, on the almost on the physics level, do you think physics can help expand the scale of compute and maybe the scale of energy required to make that computer happen?

Yeah, one hundred percent. I think this is like one of the biggest things that physics can help within its an obvious kind of low hanging fruit situation where uh, the heat generation, the inefficiency, the waste of existing high level computers is nowhere near the efficiency of our brains is hilariously worse and we kind of having tried to optimize that hard on that frontier.

I mean, your laptop heats up when you're sitting on your lap, right? Doesn't need to. Your brain doesn't heat up like like that.

Um so clearly there exists in the world of physics the capability of doing these computations with much less waste heat being generated. And I look forward to people doing that. yeah.

Are you excited for the possible of a nuclear fusion?

I am cautious ously, optimistic, excited to be too strong. I mean, to be great, right? But if we really tried solar power IT would also be great.

I I think earlier discovers that this, that the future of humanity on earth will be just the entire surface of earth, is covered in solar panels and data sectors.

Why would you waste surface of the earth with solar panel? Put them in space?

Sure, you can go in space. Yeah.

space is bigger than earth.

Yeah, just saw a pals everywhere. Yeah, just like IT already have.

Fusion is called the sun.

Yeah, true. And probably more more efficient ways of catching .

net energy sending IT down is the .

hard part. So in data centers, the computer centers can expand to with that, the future, if A I is as effective as a promise as I possibly could be 嗯， is the competition keeps increasing and perhaps the services between efficiency and and scale, there are .

constraints right now. There are certain of energy, certain of damage we can do to the environment before does not worth IT anymore. So yeah, I think that's a new question. In fact, it's it's kind of frustrated because we get Better and Better at doing things efficiently, but we invent more things we want to do faster than we get good at doing them efficiently. So we're continuing to make things worse in various ways.

I mean, that's the dance of humanity. Will cost of creating Better, Better, Better technologies that are potentially causing a lot more harm. And that includes for weapons, includes A I used as weapons that includes nuclear weapons, of course, which is surprising to me that we haven't destroyed human civilization yet. Giving how many nuclear warhead are out there?

Look, i'm with a between nuclear and bioweapons. IT is a little bit surprising that we haven't cause enormous devastation. Of course, we did drop to atomic on japan, but compared to what could have happened or could happen tomorrow, IT could be much worse.

Yeah, IT doesn't like there's a underlying speaking of quantum fields, like a, like a, like a field of goodness within the the human heart that like in some kind of game theoretic way we create really powerful things that could destroy each other and the greed and ego and all this kind of power hungry dictators that are play here with in all the geopolitical landscape but we somehow always like don't go too far .

yeah but that's exactly what you would say right before you want try before going too far and .

that's why we don't see aliens um so you're like I mentioned association was set of institute. I just would love to take a stroll down the landscape of ideas explored there. So they look at complexing in all kinds of ways. What would you think about the emergence of complexity from simple things interacting simply?

I think it's a fast topic. I think that's why i'm thinking about these things these days rather than the papers that I was describing you before. Um you know all of those papers that described before are guesses like what of the laws of YSL s are different in the following way and then you can work out the consequences.

At some point in my life I said, like what is a chance of going to get right? Know einstein guest right? It's even one per guest, right? But a very small number of times the people get right.

Where's with the emergence of complexity from simplicity? I I really do things that we haven't understood the basics yet. I think we're still kind of prepare dignity.

They're been some spectacular discoveries. Um people like Jeffery west is sfa and others have really given us true insights into important systems. But still there's a lot of the basics I think are not understood.

And so searching for the general principles is, is what I like to do. And I think it's absolutely possible that going to be a little IT more subsidy than that. I think this is a kind of cliche.

I think the key is information, and I think that what we see through the history of the universe, as you go from simple to more, more complex, is really subsystems of the universe, figuring out how to use information to do whatever, to survive or to to thrive, to reproduce. I mean, that's that's the sort of fuel, the leverage, the resource that we have um for a while anyway until the heat death. But that's where the complexity is really driven .

by yeah but the mechanism of IT. What I mean you mentioned, jeffrey, was what are interesting, including the progress in this realm and what are systems that interests you into information? So mean, for me, just as a as a fan of complexity, just even looking at simple client to us is always just a fascinating way to the emergence of complexity.

So for those of the listeners who don't know viewers, selly automated, come from in imaging, a very simple configuration, for example, that of once and zeros along a line. And then you make a rule that says, OK, i'm going to evolve this in time. And generally, the simplest ones start with just each block of three ones and zeros have a rule that they will determined sly go to either one or a zero.

And you can actually classify all the different possibilities is a small number of possible selling automata of that form. And what was discovered um by various people, including stevie world from is some of these solar automata have the future that you start from almost nothing like zero zero zero zero one zero zero zero zero and you'd let IT rip and IT becomes wildly complex. okay?

So this is very provocative, very interesting. It's also not how physics works at all because as we said, physics conserves information. You can go forward backwards.

The salary automata do not. They're not reversible in any sense. You've built in an arrow of time. You have a starting point and the new evolve.

So what i'm interested in is seeing how in the real world, with the real laws of physics and underlying reversibility but macro scope c reversibility from entropy in the airtime meta, how does that lead to complexity? I think that does an answer able question. I don't think it's about time are really helping us in that one.

So what is in that? What is the landscape of entropy in the universal look like?

Well, entropy y is hard to localize. It's the property of systems, not of parts of systems, right? Um having said that, we can do approximate uh answers to the question and the answer is black holes are huge and entropy, most us for this way, the whole observable universe that we were in had a certain amount of entropy before stars and planets and black hole started to form ten to the eighty eight. I can even tell you the customers, okay, the single black holder center of our galaxy has antrobus ten to the ninety single black holder center of our galaxy has more entropy than the whole universe used to have not too long ago. So most of the entropy in the universe today is in the former black holes.

Okay, that's factually first. A the second invoice, if we take black holes away, what are the different interesting protection ation in entropy across space? What where is where do we earth links fit into that?

The interesting thing to me is that if you start with a system that is isolate different the rest of the universe, and you start IT and low entropy, there's almost a serum that says if you're very, very, very low entropy, the the system looks pretty simple because this low entropy means there's only a small number of ways that you can be arranged the parts to look like that.

So if there is not that many ways the answers going to look simple, but is also almost of the ARM that says, when you written maxim entropy, the system is going to look simple because it's all smear out. If I had like interesting structure, then they would be complicated, right? So entropy in this isolated system only goes up.

That's the second of the moyna ics. But complexity starts low, goes up and then goes down again. Sometimes people mistakenly think that complexity, or life or whatever, is fighting against the second of thermal dynamics, finding against the increase of entropy.

That is precisely the wrong way to think about IT. We are surfers riding the way of increasing entropy. We rely on increasing entropy to survive.

That is part of what makes a special this table maintains its stability mechanically, by which I mean, there's molecules there, have forces on each other, and IT holds up. You and I aren't like that. We maintain our stability dynamically by ingesting food, fuel, right? Food, water and air and so forth, burning IT, increasing its entropy. We are non equilibrium, quasi steady state systems. We are using the fuel the universe gives us in the form of low entrepreneurship to maintain our stability.

I just wonder what the mechanism of surfing looks like. I mean that first. So I mean, one question to ask, do you think it's possible to have a kind of signs of complexity where you have very precise ways or clearly defined ways of measuring complexity?

I think IT is and I think we don't it's possible to have IT. I don't think we had have IT because in part because complexity is not a unavailable thing, there's different ideas to go under the rubrics of complexity. One version is just come algo of complexity, right?

If you have a configuration or a string of numbers or whatever, can you impress IT so that you have a small program that will output that? That's commodo of complexity, but that's the complexity of a string of numbers, okay? It's not like the complexity of a problem, right?

Computational complexity, the traveling salesmen problem or factory large numbers as a whole different kind of question. That is also about complexity. So we don't have a sort of unified view of IT.

Anything is possible to have a complexity of physical system yeah in the same way we do entropy. Yeah you think that's a shock of paper? What we are .

working on various things. My the the glib thing that i'm trying to work on right now with with a student is complex of genesis. How does complexity come to be if all the universe is doing is moving from low entries to high entry? Sexy name, it's a good name yeah I like the name that is right. The paper .

sometimes a name yeah roles by other name what which which in which context um the birth of complexity are you most well.

I think that comes in stage, right? So I think that if you go from the i'm going a physicist so biologists setting evolution will talk about how complexity volts all the time, the complexity, the genome, the complexity of our physiology. But they take for granted that life art existed, you know, and entropy increasing and so forth.

I want to go back to the beginning and say the early universe was simple and low interpret and entrepreneurship es with time and the universe that differentiates and becomes more complex. But that that statement, which is in dispute ably true, has different meanings, because complexity has different meaning. So what of the most basic primal version of complexity is, is what you might think of as configuration tional complexity.

That's what commotion ve gives that how much information do you need to specify the configuration ation of the system? Then there's a whole other step where subsystems of the universe start burning fuel, right? So in many ways a planet and a star are not that different in configuration complexity.

The both fears with density high, the middle and getting less as you go out. But there's something fundamentally different because the star only survives as long as IT as fuel, right? I mean, then he turns to new around df, a right door for whatever.

But as a star, as a main sequence star, IT is an out of equal liberum system. But it's more, less static, right? Like if I spill the coffee mug and IT falls in the process of falling is out of equilibrium.

But it's also changing all the time. A specific kind of system is where is looks for a microscopically stationary like a star. But underneath the hood is burning fuels to be the band in order to maintain that's stability.

So as stars formed that, that's a different kind of complexity that comes to be then there's another kind of complexity that comes to be, roughly speaking, at the origin of life because that's where you have information really being gathered and utilized by subsystems of the universe. And then arguably, there's any number of stages passed that. I mean, one of the most obvious ones to me is we talk about simulation theory, but you and I run the simulations in our heads to just not that good, but we imagine different hypothetical futures, right?

Bacteria don't do that. So that's the kind of information processing that is a form of complexity. And so I would like to understand all these stages and how they fit together.

The imagination.

Yeah, mental time travel.

Yeah, the things going on in my head, but i'm imagining morals. There are super compressive representations of those worlds, but I get to the essence of them. And may be as possible with non human computing type devices to do those guys of simulation than more, more compressed wise.

There's an argument to be made that literally what separates human beings from other species on earth is our ability to imagine counter factory local features yeah I mean, that's one of the big features.

I don't know everyone has their own favorite able feature.

but that's why I was an argument to be made. I did a podcast episode IT with adami to develop slowly.

I did different podcast started to keep mentioning podcast episode did but malcomb c iver who is an engineer in northwestern as a theory about um one of the major stages in evolution is when fish first climbed on the land and of coming of course, that is a major stage of evolution, but in particularly there's a cognitive shift because when you're a fish swimming under the water, the attenuation length of light in water is not that long. You can see kilometers away, you can see meters away and you're moving at meters per second. So all of the evolutionary optimization is make all of your decisions on a time scale less than a second.

When you see something new yet to make a ratified decision, what to do about IT? As soon as you clip on the land, you can essentially see forever, right? You can see stars and sky.

Um so now a whole new mode of reasoning opens up where you see something far away. And rather than saying, look up people, I see this, I react. You can say, okay, I see that thing.

What if I did this? What if I did that? What if I did something different? And and that's the birth of imagination.

Eventually you've been critical on pacis.

M, yes, you notice that, right?

Can you make the case for panza against IT? So psychism the idea that conscious, as for me, it's all matter, maybe it's so the fundamental force, or of physics, of the way of the fabric of the universe.

pain psychos thought everywhere.

conscious ness everywhere, right? To a point of entertainment. The idea of fruit, which sort of a fan is, is wonderful to watch. And you've had great episodes with with pen psychist that's in your podcast where you go at IT.

I had David jammers who know one of worlds, great philosopher, and he is he is pen psychosis. Curious yeah he's he doesn't commit to anything but he's certainly willing entertain IT Philip goff, who i've had, he is a great guy, but he is devoted. Depends on, in fact, he is almost single handily responsible for the upsurge.

Ent of interest in panza m in the popular imagination. And the argument for IT is supposed to be that there is something fundamentally uncapturable about conscious awareness by physical behaviour of atoms and molecules. So the pain psychosis will say, look, you can tell me maybe someday, through advances of neuroscience, and what have you, exactly what happens in your brain, and how that translates into thought and speech and action.

What you can tell me is what IT is like to be me. You can tell me what I am experiencing when I see something that is red, or I taste something that is sweet. You can tell me what neurons fire, but you can tell me what i'm experiencing.

The first person in a subjective experience is simply not capture able by physics. And therefore this an old argument, of course, but then therefore supposed to be, I need something that is not contained within physics to account for that. And i'm gna call IT mind.

We don't know what IT is yet. We're going to call IT mind. IT has to be separate from physics. And then there's two ways to go. If if if you buy that much, you can either say OK, we'll be a dual list.

I'm going to believe that there's matter and mind and they are separate from each other and they are interacting somehow or that's a little bit complicated and sketchy as far as physics is going to go. So i'm going to believe in mind. I'm going to put a prior to matter.

I'm going to believe that mind comes first, and the consciousness is the fundamental aspect of reality. Everything else, including matter and physics, comes from IT. That would be at least as simple as physics comes first. Right now, the physical list such as myself, i'll say I don't have any problem explaining what is like to be you or what you experience when you see red. It's a certain way of talking about the Adams in the neurons seta that make up you, just like the hardness or the Brownness of this table. These are words that we attach to certain underline configurations of ordinary physical matter, likewise sadness and redness, or whatever our words we attach, do you to describe what you're doing? And when he comes to consciousness in general, i'm very quick to say I do not claim to have any special insight on how consciousness works, other than I see no reason to change laws of physics to account for IT.

If you don't have to change a lot of physics, what do you think that emerges from his consciousness and illusion? That's almost like a short hand that we humans used to describe a certain kind of feeling. We have one interacting with the world there. Is there some big leap that happens at some stage? I almost never .

use the world delusion. Illusion means that there's something that you think you're perceiving that is actually not there. Like in oasis in the desert is an illusion.

IT has no causal efficacy. If you woke up to where the way supposed to be is that you are wrong about him being there. That's different than something being emergent. We're non fundamental, but also real like this table is real even though I know it's made of atoms that doesn't remove the realness from the table. I think the consciousness and free will and things like that are just as real in tables and chairs .

always is in the desert, does have caul efficacy. And that your third l to draw incorrect .

conclusions about the world.

sure. But imagining a thing can sometimes bring IT to reality, as we've seen, and that has a kind of a causal efficency. sure.

But your understanding of the world in a way that gives you power over IT and influence over IT is decreased rather than increased by believing in that oasis that is not true about conscious ness. For this table.

you don't think you can increase the chance of a thing existing by imagining IT existing .

unless you build IT or make IT. No.

that's what I mean, like imagining humans can fly if you the .

right brother, humans are flying right? In terms of counterfactual in the future, absolutely imagination is crucially important, but that's not an illusion.

That's just up. okay? So the possibility, the future verses what reality is. I mean, the future is a concept, so you can well, time. Time time is just the concept that you can play with that but yes reality um so to you so for example, love ask is so down as often and thing says the entirety of the conversation has been having about spacetime is an illusion, is a possible free to still make the case for that he make the case for and against reality as I think uh, he writes that the laws of physics as we know them was based time is a kind of interface. So much deeper thing that we don't at all understand, and they were fooling ourselves by constructing this world.

Well, I think this is like part of that idea that is perfectly respectable, and part of IT that is perfectly nonsensical. And i'm not even going to try to steal men the nonsensical part. The real part to me is is what is called structural realism.

So we don't know what the world is at a deep fundamental level, right? Let's put ourselves in the in the minds of people living two hundred years ago like they they know about quality mechanics. They didn't know about relativity.

That doesn't mean they were wrong about the universe that they understood. They had newton s laws, right? They could predict what time the sun was gonna rise perfectly well in the progress of science.

The words that would be used to give the most fundamental description of how you were predicting the sun would rise changed because, you know, you have curved space, time and things like that, right? And you didn't have any those words two hundred years ago. But the prediction is the same.

why? Because that prediction, independent of what we thought the fundamental ontology was, the prediction pointed to something true about our understanding of reality. To call an illusion is just wrong. I think we might not know what the best, most comprehensive way of stating IT is, but it's still true.

Is IT true in the way, for example, belief in god is true, because for a most human history, people have believed in a guard or multiple guards, and that seemed very true to them as an explanation for the way the world is. Some of the deeper questions about life itself at the human condition and why certain things happen. That was a good explainer. Um so you that's not .

an illusion. No.

I think I was .

completely illusion. I think it's a very, very reasonable illusion to be under. There are illusions. There are substantive claims about the world that go beyond predictions that we can make and verify uh which later found to be wrong and the existence of god was one of them um if those people at that time had abandon their belief in gun and replaced with the mechanistic universe, they would have done just as well, had understanding things right uh again, because there are so many things they didn't understand. IT was very reasonable for them to have that belief that wasn't that they were dummies or anything like that. But that is, as we understand the universe Better and Better, some things stick with us, some things get replaced.

So like you said, you are a your believer of the mechanistic universe. Ah here naturalist, as you've described, a poetic naturalist. That's right. What's the word poetic? What is naturalism and what .

is poetic naturalism? Naturalism is just the idea that all that exists, the natural world, there's no supernatural world. You can have arguments, bet what that means, but I would claim that the argument should be about what the word supernatural means, not the word natural.

The natural world is the world that we learned about by doing science. The politic part means that you shouldn't be, too, I want to say, fundamentalist about what the natural world is. As we went from neutronic space time to einsteinian space time, something is maintained there.

There is a different story that we can tell about the world. And that story in the new tony regime, if you want to fly a rocket to the moon, you don't use generativity used tony mechanics. That story worked perfectly well. The poetic aspect of the story is that there are many ways of talking about the natural world. And as long as those ways left on to something real and cauSally efficacies about the functioning of the world, then we attribute some reality.

in truth, to them. So the poetic really looks at the at the, let's say, the pot had questions at the edge of science is more open to them.

Is doing double duty a little bit. So that's why it's confusing the the more obviously pectore duty is doing is the tables are real. Even though you know that is really a quantum field theory way function, right tables are still real.

There are a different way of talking about the underlying deeper reality habit. The other duty is doing is that we move beyond the purely descriptive vocabulary for discussing universe onto Normative and prescriptive and judgmental ways of talking about the universe. This painting is beautiful.

That one is ugly. This action is morally right. That one is morally wrong.

These are also ways of talking about the universe. They are not fixed by the phenomenon. They are not determined by our observations.

They cannot be ruled out by a crucial experiment, but they're still valid. They might not be universal, they might be subjective, but they're not arbitrary. And they do have a role in describing .

how the world works. So you don't think is possible to construct experiments that explore the arms of morality and even meaning. So those are just those. Those are subjective.

Yeah, they're human. They're personal.

But do you think that just because we don't have a the tools of science have not expanded enough to incorporate the human experience?

No, I don't think that's what that is. I think that what we mean by aesthetics or morality are we're attaching categories, properties, two things that happen in the physical world. And there is always going to be some subjectivity to our attachment and how we do that. And that's OK. The faster we recognize that and deal with that, the Better off will be.

But if we deeply and fully understand the function of the human mind won't be able to incorporate that.

No, that will absolutely be helpful in explaining why certain people have certain moral belief. IT won't justify those beliefs as right or wrong.

Do you think this possible to have a general relativity? But that includes the observer effect, where the human mind is the observer sort like how we move um in staying with gravity, more space time. How does the human mind more reality and have a very thoro theory of how that morphing actually happens?

That's a very polluted question.

Like what is possible?

The answer is yes. I think that there's no. I think that we are part of the physical world and the natural world. Physical ism would have been just as good to word to use as naturalism, maybe even a more accurate word, but a little bit more off putting. So I do, I do want to snap your more attractive label than physical ism.

Are there limits to science?

short? We just talked about one right. Science can tell you right from wrong. You need signs to implement your ideas about writing wrong. If you are functioning on the basis of an incorrect view of how the world works, you might very well think you're doing right, but actually be doing wrong. But all the science in the world won't tell you which action is right, in which action is wrong.

You know, dictators, people in power sometimes use science as an an authority to a convince what's write wrong study. Not see science is fascinating.

but there's an instrumentally view here. You have to first decide what your goals are, and then science can help you achieve those goals. If your goals are horrible, science has no problem helping you achieve them. Science is happy to help out.

Let me ask about the method behind the madness on several aspects of your life, so you mentioned that you approach to a writing for research and writing popular books. How do you find the time of the day like is the day in the life .

of Shawn cks?

So you don't have a thing where in the morning you're like you, you try to fight for two hours somewhere.

I don't i'm really terrible at that, my strategy for finding time just to ignore interruptions in emails. But it's a different time every day. Some days that never happened.

some weeks and never happen because you're extremely prolific. So like you're able to have days when you don't, right? Oh, and still right the next day.

Oh, wow. That's a rare thing, right? A lot of prolific writers will will carve out two hours because otherwise I just disappears .

right now I get that. Yeah, I I do. And yeah, I just like I everyone is you know has their boy balls or whatever. So i'm not able to do that. Therefore, I have to just figure that out on the fly IT was the .

actual process look like your rating? Uh, popular stuff. You get behind the computer.

Yeah, get behind the computer and my way of doing IT. So my wife, Jennifer, is a science writer, but it's interesting because our techniques are entirely different. You know, he will think about something, but then he will free write.

So just consider the computer and right, like I think this, I think, and then that will be vastly compressed, edited in the rewritten or whatever, into the, the final thing happens. I will just like that there, silently thinking for a very long time. And then I will write what is almost the final draft. So a lot of IT happens if my pic of scribes for an outline or something like that, but a lot of IT is in my brain before it's on the page.

So that's the case. The the biggest ideas in the first the quanta book in the space time motion book.

yeah quanta in fields, which is actually mostly about quantum field theory in particle physics um that's coming out in may and that is um i'm letting people in on things that no other book let them in on. So I hope it's worth that is a chAllenge because you love equations.

I mean, you did the same thing was best time you he does something quite interesting, which is like you made the equation and central piece of a book.

right? There's lot of equations book to is is um goes further in those directions then book one did. So it's more cool stuff.

It's also more mind bending. It's more the chAllenge. Book three that i'm writing right now, uh, is called complexity emergence. Oh wow, and that will be the final part .

of the trilogy. Oh, that's fascinating. So there's a lot of probably ideas there, there. I mean.

that's a real cutting edge. But you know, i'm not trying to be cutting IT. In other words, i'm not trying to speculate in these books.

Obviously, other books i've been very free about speculating, but the point of these books is to say things that five hundred years now will still be true. And so there are some things we know about, complexity, emergence, and I want to focus on those. And I I will mention, i'm happy to say this is something that needs to be speculated. About, but I won't pretend to be telling you what one is.

what I want. You somehow found the body between the rigor mathematics and still accessible. interesting.

I try, I mean, look, this, these three books, the biggest ideas books, are absolutely experiment. They're gonna appeal to a smaller audience than other books will um but that audience should love that like my sixteen year old self would have been you to.

I tell you, just looking back in his street, those books, the trailer to be truly .

special in that way. Work for lord the rings so I figured, why not mean you talk?

Yeah, different styles, different topics.

same ultimate reality.

Like we mention minds, cape pocket, I love IT. You interview a huge variety of experts for more kinds of fields. So just several questions I want to ask. How do you prepare like how do you prepare to have a good conversation? How do you prepare in a way that satisfied, makes your own curious mind happy?

All that kind of stuff? yeah. Now these are a great questions. And i've sort of struggled and changed my techniques over the years over five year old, but I might be approaching six years old now.

Um I started out over preparing when I first started like I had a journey that I was going to go down. Many of the people I talk to our academics or you know think there's who write books so they have a story to tell. I could just say, okay, give me your lecture. And then an hour later, stop.

right? So the mistake is to sort of anticipate what the lecture would be and to ask the leading questions that would pull IT out of them. What I do now is much more here, the points here, like the big questions that I am interested in, as I have a much sketch here, outline to start and then try to make IT more of a real conversation. Um i'm helped by the fact that IT is not my daydream so I I strictly limit myself to one day of my life per podcast episode on average and some day's take more and that includes not just doing the research but inviting the guest recording IT, editing and publishing IT. So I need to be very.

very efficient to that. You enforce constraint for yourself in which creativity can emerge that's right.

And yeah, look, sometimes if i'm interviewing a theoretical physicist, I can just go in and where interviewing an economist or history and i've do a lot of .

work to find yourself, uh, getting lost in rabbit holes that serve no purpose except satisfying your own curiosity and then potentially expanding the range of things you know that can help your actual work research writing .

yes um on both counts you know I do is some people have so many things to talk about that you don't know where to start or finished, right? Others have a message. And one thing I discovered over the course of these years is the correlation with age.

Like there are brilliant and people and and I try very hard on the d cast to sort to get all sorts of people right different ages and things like that um and bless their hearts the most brilliant Young people are not as practiced at wondering past their literal research right they are less mastery over the field as a whole much less how to talk about IT where is certain older people, just like have their panting answers and that's kind of boring, right? So you want, you want somewhere in between. You know, the ideal person who is is has a brought in of a scope that they can wander outside their specific papers. Theyve written ten, but they are not overly practiced. So there is giving .

you there can answer I feel like there is like a connection to the metaphor .

of entrepreneur complexity as you .

said there ah you also do incredibly amazing ed that people should sign up to a page on and because you can get to ask questions so 小口 well， for several hours you just answer in fascinating ways a some really interesting questions. Is there something you could say about what the process of finding the answers to those that's .

a great one again, is evolved over time? Um yes, so he asked me anything. Um episodes were first when I started doing them, there were only four patriots b scribers.

Both listen to and to ask the questions. But then I actually asked my patrie on subscribers, would you like me to release them publicly? And they overwhelmingly voted yes.

So I do that. So the patron supporters asked the questions. Everyone can listen. And also at some point, I really used to try to answer every question, but now there's just too many. So I I have to pick and that's fraught with peril.

And my personal standard for picking questions to answer is what are the ones I think I have interesting answers to give for, right? So that both means if it's kind of the same mold question about special relativity that have gotten one hundred times before, i'm not going to answer IT because you can just google that to the easier um there are some you know very clear attempts to ask an interesting question uh the onest ly just I don't have an answer to you like I read this science fiction novel. What do you think about IT like I haven't read IT so I can help you there.

Um what's your favor color you know I can tell you what IT is but not that interesting and um so this I try to make IT a mix um I tried to like is not all these questions, not all physical y questions. I will talk about food or movies or politics or religion of as well. People know I keep suggesting the people ask me for relationship advice.

but they never do. Yeah heard they have first one .

i'm willing to do IT but a little reluctant ant because I don't actually like giving advice um but I do but i'm happy to talk about those topics I want to you know I want to give several hours of of of talking and I want to try to say things they haven't said before and keep IT interesting keep IT ruling. You don't like this question for next one.

Harder questions. You got ten. Remember what? What kinds of questions are difficult for you?

Rarely, but occasionally people ask me a super insightful philosophe question. Like, I hadn't thought of the things in exactly that way and I tried to be no, I try to recognize that um a lot of times is the is the opposite where it's like, okay, you're clearly confused and i'm going to try to explain why, how the question .

you should have about I but the hard questions I don't know like I don't actually .

um answer personal questions very much like the most personal I will get our questions like what do you think about more right that much I can talk about how are your cats doing happy? You talk about the cats in infinite detail. But you know very personal questions .

I don't get into, but you even touch like politics .

and stuff like, yes, no very top of politics. You know I try to be clear on you what is professional expertise? What is just me babbling? What is my level of creating in different things where you're allowed to disagree, whether if you disagree you're just wrong um and people can disagree with that also. But I do think you know I am am happy to go out on a limb a little bit. I'm happy to say, look, I don't know but here's my gas, right I just a whole solo podcast which was that and you know, it's interesting like some people I got this was great and there's a whole bunch of people like, why are you talking about this thing that you are not the world's expert in? So know.

I love the actual dance between humility and having a strong opinion and stuff, which is a great is a fascine dance to pull off. And I guess the way to do that is to just expand into all kinds of topics and play with ideas and then change your mind and all that kind of stuff yeah.

it's it's interesting because when people react against you by saying you are being arrogant about this ninety nine point nine nine nine percent of the time, all they mean is I disagree and that's all they really mean right here. You like at a very basic level, like people will accuse aist of being american. And i'm like, you think god exists and loves you, would you tell telling me that america? I think all all of this is to say just advice.

When you disagree with somebody, try to specify the subsidy disagreement, trying not to psychologize them, right, trying to say, oh, you're saying this because of this. Maybe it's true, maybe you're right. But if you had an actual response to what they were saying, that will be much more interesting .

yeah I think I wonder why is difficult for people to say or to imply I respect you, I like you, but I disagree on this and here's why I disagree. Like I wonder why they they go to this place of like what your name or your A A 一个 tesco， or your a confused or your name or you're are all the kinds of words as supposed to like. I respect a fellow human, be expLoring the world of mysteries all around us. And I disagree.

I will complicate the question even more because there's some people I don't respect or like. And I once got a blog post. I think he was called the grid of disputation and I I had a two by two grid.

And it's, are you someone I agree with or disagree with? Are you someone who I respect or or don't right? And all four quadrant are very populated. And and that what that means is there are people who i'd like, uh, and I disagree with, and there are people who agree with me and I have no respect for at all. The embarrassing allies is quarter and that was everyone's favor.

So and I just .

think being honest, right, like trying to be ask about where are, but if you actually want to move the conversation forward, forget about what do you like or don't like somebody explain the disagreement, explain the agreement. But but you're absolutely right. I completely agree. Like as a society we are not very good to disagreeing.

We instantly go to the insults yeah I mean, even on the deeper level, I think at some deep level, I respect and love the humanity dinner at the person yeah, you said that general relativity, the most beautiful theory over so far. We did find beautiful about IT.

Let's put IT this way. When I teach courses, there's no more satisfying subject to teach the general relativity. And the reason why is because IT starts from very clear, precisely articulated assumptions.

And IT goes so far, right? And you know, when I give my talk, you can find online, I probably not going to give IT again. The book.

One of the biggest ideas talk, right, was building up from, you don't know any matter, physics an hour later, you know, once times equation for generativity. And the punch line is the equation is much smarter than Albertine's time. Because everyone did not know about the big bang, he didn't know about gravitational waves, he didn't know about black holes, but his equation did. And that's, I mean, that's a maculate aspect of science more generally. But general relativists were manifest itself in the most absolutely obvious way.

a human question, what do you think of the fact that einstein didn't get the mobile prize for general .

relativity trade? He should have gotten maybe four mobile Prices. Honestly, that was certainly should. I've got the photos.

Electric effect was one hundred percent worth in nobel prize because, and people don't quite get this. Who cares about the photoelectric effect? That's like this bring minor effect. The point is his explanation for the photo. Electric effect invented something called the photo that's worth the nobel prize.

Max plunk gets credit for this in one thousand nine hundred, explaining black body radiation by saying that when a little electron is giggling in a object at some temperature gives off radiation in discrete chunks rather than continuously. He didn't quite say that's because radiation is discrete chunks, right? Is like having a coffee maker that makes one cup of coffee at a time.

IT doesn't mean the liquid comes in one cup. Quanta, right? Just are dispensing IT like that.

IT was einstein in one thousand and five who said light is quanta, and that was a radical thing. So that clearly that that was not a mistake, but also special. Relativity clearly deserve the nobel prize. And general, he clearly deserve the nobel prize. Not only were they brilliant, but they were experimentally verified.

Like everything you want to separate, you think.

yes, absolutely. Oh, humans.

whatever the explanation there I went.

have never won the nobel prize for finding the universe was expanding yeah but and .

even the fact that we give Prices is almost kind of silly, and we limit the number of people that get the prize and all that.

I think that noble Price is enormous problems, and I think it's probably a net good for the world because IT brings attention to good science, I think is probably negative for science if because that makes people want to win the noble prize.

Yeah, there's a lot of fascinating human stories underneath at all. Sciences its own thing, but it's also a collection of humans and it's a beautiful collection. This tension in this competition there's jealous y um but there is also great collaborations in all that can stuff uh the conomo who recently passed as as one of the great a stories of collaboration and um in science so all of IT, all of IT that's what humans do and so on.

Thank you for being the person that makes us celebrate science and fall in love with all of these beautiful ideas and science for writing amazing books, for being legit and still pushing forward the research sign side of IT and for allowing me and these part had questions and also for educating everybody through your own podcast. It's, uh, everybody should stop everything and subscribed and listen to everything. Episode de minds gap sode, thank you.

I've been a huge fan forever. really. Honey y would speak with me in the early days when was still starting this pocket. I mean, the world I appreciate.

Thanks very much having me on. Now that you are a big deal still having me on.

Thank you. Thanks for listening to this conversation with sean carroll. To support this podcast, please check out our sponsors in the description. And now I believe you is the words from Richard fineman study hard will interest you the most in the most undisciplined, irreverent and original manner possible. Thank you for listening, and hope to see you next time.