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Andrew Strominger
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“Still did it anyway. I'm a little bit of a contrarian, I guess. And I think that has served me well. People are always sort of disagreeing with me, and they're usually right, but I'm right enough.”
2023-02-15 · Lex Fridman Podcast · #359 – Andrew Strominger: Black Holes, Quantum Gravity, and Theoretical Physics · IDENTIFIED FROM THE TRANSCRIPT · source
“Personally, Ah, I'm lucky. I'm well equipped for that. When I Started out in graduate school, the problem of quantum gravity was Not considered interesting?”
2023-02-15 · Lex Fridman Podcast · #359 – Andrew Strominger: Black Holes, Quantum Gravity, and Theoretical Physics · IDENTIFIED FROM THE TRANSCRIPT · source
“Well, he was one of my great teachers. Of course, he's older than me, and I was reading His textbooks in. In graduate school. You know, I learned a lot about relativity from him. I learned about passion for a problem. I learned about Not caring what other People think. Physics is an interesting culture, even if you make a great discovery like Hawking did. People don't believe everything you say. In fact, people love to disagree. It's a culture that cherishes disagreement. And so he kept ahead with what he believed in. And sometimes he was right and sometimes he was wrong.”
2023-02-15 · Lex Fridman Podcast · #359 – Andrew Strominger: Black Holes, Quantum Gravity, and Theoretical Physics · IDENTIFIED FROM THE TRANSCRIPT · source
“Well, you know, I love the guy. He's so passionate about. Physics, he just. Yeah, his. His oneness The problem, and I mean, it's.”
2023-02-15 · Lex Fridman Podcast · #359 – Andrew Strominger: Black Holes, Quantum Gravity, and Theoretical Physics · IDENTIFIED FROM THE TRANSCRIPT · source
“A critical error that this was the critical error and that understanding this would get us the whole story. And that could well be.”
2023-02-15 · Lex Fridman Podcast · #359 – Andrew Strominger: Black Holes, Quantum Gravity, and Theoretical Physics · IDENTIFIED FROM THE TRANSCRIPT · source
“Well, what we showed is that there's an error in the argument that all black holes are the same because they hadn't kept track of these very subtle things. And whether or not this is the key error in the argument. Remains to be seen, or whether this is a technical point.”
2023-02-15 · Lex Fridman Podcast · #359 – Andrew Strominger: Black Holes, Quantum Gravity, and Theoretical Physics · IDENTIFIED FROM THE TRANSCRIPT · source
“Everywhere They're able to store information, they're able to store an arbitrary large amount of information. So what we pointed out is, so what these things really do, one way of thinking of them is they rush off to the edges of the universe, spreading out all over the space. It's like saying they rush off to the energy edge of the universe. And that includes if the interior of the black hole is not considered part of the universe, that includes the edge of the black hole. So we need to set up our description of physics so that all the things that are conserved Are still conserved in the way that we're describing them, and that will not be true if we ignore these things. We have to keep careful track of these things. People had been sloppy about that, and we learned how to be very precise and careful about it”
2023-02-15 · Lex Fridman Podcast · #359 – Andrew Strominger: Black Holes, Quantum Gravity, and Theoretical Physics · IDENTIFIED FROM THE TRANSCRIPT · source
“But if you do this, you'll get into trouble. And one of the ways that you'll get into trouble is that even though it has zero energy, it doesn't have zero angular momentum. It's a photon, it always has angular momentum one. If it's a graviton, it's angular momentum two. So you can't say that the state of the system with the zero energy photon should be identified with the one. Without the zero energy photon that we can just ignore them because then you will conclude that angular momentum is not conserved. And the Vangular momentum is not conserved, things won't be consistent. And of course, you can have a lot of these things, and typically you do get a lot of them. And when you can actually do a calculation that shows that every time you scatter Particles, you create an infinite number of them.”
2023-02-15 · Lex Fridman Podcast · #359 – Andrew Strominger: Black Holes, Quantum Gravity, and Theoretical Physics · IDENTIFIED FROM THE TRANSCRIPT · source
“Yeah, so the soft gravitons and photons have been Known about since the 60s, but exactly what we're supposed to do with them or how we're supposed to think about them, I think has been Well, understood only recently. And in quantum mechanics, the energy of a particle is proportional to Planck's. So, when the energy goes to zero, the wavelength gets to infinity. Now, if something has zero energy and it's spread all over the universe, in what sense is it actually there? That's been the confusing thing to make a precise statement about when something is and isn't there. Now, the simplest way of seeing So people might have taken the point of view that if it has zero energy and is spread all over the universe, it's not there, we can ignore it.”
2023-02-15 · Lex Fridman Podcast · #359 – Andrew Strominger: Black Holes, Quantum Gravity, and Theoretical Physics · IDENTIFIED FROM THE TRANSCRIPT · source
“That's the soft hair. Right. So, and soft is a word that is used in physics for things which have very low energy. And these things actually carry no energy. There are things in the universe which carry no energy.”
2023-02-15 · Lex Fridman Podcast · #359 – Andrew Strominger: Black Holes, Quantum Gravity, and Theoretical Physics · IDENTIFIED FROM THE TRANSCRIPT · source
“So what Hawking and I showed, and also Malcolm Perry, is that one has to be very careful about what happens at the boundary of the black hole. And this gets back to something I mentioned earlier about when two things which are related by a coordinate transformation are and are not equivalent. And, um, And what we showed is that they're very subtle imprints when you throw something into a black hole. They're very subtle imprints left on the horizon of the black hole, which you can read off at least partially what went in. And so this invalidates Stevens' original argument that the information is destroyed.”
2023-02-15 · Lex Fridman Podcast · #359 – Andrew Strominger: Black Holes, Quantum Gravity, and Theoretical Physics · IDENTIFIED FROM THE TRANSCRIPT · source
“And if you throw something into a black hole, it gets sucked in. And if you throw in a red book or a blue book, Black hole gets a little bigger, but there's no way within Einstein's theory of telling how they're different. And that was one of the assumptions that Hawking made in his 1974-75 papers in which he concluded that black holes destroy information. You can throw encyclopedias, thesis defenses, the Library of Congress.”
2023-02-15 · Lex Fridman Podcast · #359 – Andrew Strominger: Black Holes, Quantum Gravity, and Theoretical Physics · IDENTIFIED FROM THE TRANSCRIPT · source
“Okay, so first of all, The hair on black holes is a word that was coined by the greatest phrase master in the history of physics John Wheeler invented the word black hole. And he also said that he made the statement that black holes have no hair. That is, every black hole in the universe Is described just by its mass and spin. They can also rotate, as was later shown by Kerr. And, um, And this is very much unlike a star, right? Every star of the same mass is different in a multitude of different ways, different chemical compositions, different motions of the individual molecules. Every star in the universe, even of the same mass, is different in many, many different ways. Black holes are all the same. And that means when you throw some in Einstein's description of them. Which we think must be corrected”
2023-02-15 · Lex Fridman Podcast · #359 – Andrew Strominger: Black Holes, Quantum Gravity, and Theoretical Physics · IDENTIFIED FROM THE TRANSCRIPT · source
“Years. I haven't really been working so much on string theory proper. I've been sort of taking the lessons that we learned in string theory and trying to apply them to the real world using only, assuming only what we know for sure about the real world.”
2023-02-15 · Lex Fridman Podcast · #359 – Andrew Strominger: Black Holes, Quantum Gravity, and Theoretical Physics · IDENTIFIED FROM THE TRANSCRIPT · source
“That is the great thing about being a theoretical physicist is Anybody can very quickly stump you with they going to the next level of wise. So I can just keep asking. Yeah, you could just keep asking, and it won't take you very long So, the trick in being a theoretical physics is finding the questions that You can answer. So, the questions that we think we might be able to answer now, and we've partially answered, is that there is a holographic explanation for certain kinds of things and theory. We've answered that. Now we'd like to take what we've learned, and that's what I've mostly been doing for the last 15 days.”
2023-02-15 · Lex Fridman Podcast · #359 – Andrew Strominger: Black Holes, Quantum Gravity, and Theoretical Physics · IDENTIFIED FROM THE TRANSCRIPT · source
“How a black hole Could store information on a holographic plate. I think we do understand in great mathematical detail and also intuitively, and it's very much like an ordinary Or you'll have a holographic plate and you, it contains all the information, you shine a light through it, and you get an image which looks three-dimensional.”
2023-02-15 · Lex Fridman Podcast · #359 – Andrew Strominger: Black Holes, Quantum Gravity, and Theoretical Physics · IDENTIFIED FROM THE TRANSCRIPT · source
“That's where Hawking radiation comes in. And that problem of how the information gets in and out, you can't, you couldn't have explained how information gets in and out of an iPhone without first explaining how it's stored in the first place.”
2023-02-15 · Lex Fridman Podcast · #359 – Andrew Strominger: Black Holes, Quantum Gravity, and Theoretical Physics · IDENTIFIED FROM THE TRANSCRIPT · source
“Well, there's really two hawking problems. They're very closely related. One is how does the black coal store the information? And that is the one that we solved in some cases. So it's sort of like your smartphone. How does it store its 64 gigabytes? Well, you rip the cover off and you count the chips and there's 64 of them each with a gigabyte. And you know there's 64 gigabytes. But that does not solve the problem of how you get information in and out of your smartphone. To understand a lot more about Wi Fi and the internet and the cellular.”
2023-02-15 · Lex Fridman Podcast · #359 – Andrew Strominger: Black Holes, Quantum Gravity, and Theoretical Physics · IDENTIFIED FROM THE TRANSCRIPT · source
“The three dimensional image and the holographic plate. The whole gram is what Einstein discovered, and the holographic plate is what we discovered. And this idea that you could describe things very, very concretely in string theory in these two different languages, of course, took off and was applied to many different Many different contexts within string theory.”
2023-02-15 · Lex Fridman Podcast · #359 – Andrew Strominger: Black Holes, Quantum Gravity, and Theoretical Physics · IDENTIFIED FROM THE TRANSCRIPT · source
“And it's trivial to see that they're the same, but there are many statements that can be made in mathematics and mathematical physics that are equivalent but might take years to understand that they're equivalent and might take the invention or discovery of whole new fields of mathematics to prove their equivalent. And this was one of those. We found an alternate description. Of certain black holes in string theory, which we could prove was equivalent. And it was a description of the black hole as a hologram. Can be thought of a holographic plate. that could be thought of as sitting on the surface of the black hole and the interior of the black hole itself sort of arises as a projection or the near horizon region of the black hole arises as a projection of that holographic plate. So the two descriptions were the hologram.”
2023-02-15 · Lex Fridman Podcast · #359 – Andrew Strominger: Black Holes, Quantum Gravity, and Theoretical Physics · IDENTIFIED FROM THE TRANSCRIPT · source
“The inconsistency, right? Something else could have happened. It would have been a major. A major change in the way we think about string theory. And it was a good thing that one supposition that the world is made of strings solves two problems, not one. It solves the infinity problem and it solves the Hawking's problem. And also the way that it did it. Was very beautiful. It gave an alternate description. Alternate description thing of things are Very common. I mean, we could take a simple example, this bottle of water here is 90% full. I could say it's 90% full. I could also say it's 10% empty. Those are obviously the same statement.”
2023-02-15 · Lex Fridman Podcast · #359 – Andrew Strominger: Black Holes, Quantum Gravity, and Theoretical Physics · IDENTIFIED FROM THE TRANSCRIPT · source
“And sometime in the early 90s, We began to understand the mathematics of string theory better and better, and it came to the point where it was clear that this was something we might be able to compute. It was a kind of moment of truth for string theory because if it hadn't given the answer. That Beckenstein and Hawking said it had to give for consistency. String theory itself would have been inconsistent and we wouldn't be doing this interview.”
2023-02-15 · Lex Fridman Podcast · #359 – Andrew Strominger: Black Holes, Quantum Gravity, and Theoretical Physics · IDENTIFIED FROM THE TRANSCRIPT · source
“Well, that is one of the little off the track here, but that certainly is one of the nice things about being a physicist is you spend a lot of time thinking about insides of black holes and billions of years in the future. And it sort of... Gets you away from the day to day. Into another fantastic realm. But I was answering your question about. There could be information in a black hole So Einstein only gave us an approximate description, and we now have a theory that corrects it string theory. And now sort of was the moment of truth. Well, when we first discovered string theory, we knew from the get-go that string theory would correct what Einstein said, just like Einstein corrected what Newton said. But we didn't understand it well enough. Actually, compute the correction, to compute how many gigabytes there were.”
2023-02-15 · Lex Fridman Podcast · #359 – Andrew Strominger: Black Holes, Quantum Gravity, and Theoretical Physics · IDENTIFIED FROM THE TRANSCRIPT · source
“Well, the speed of lights is a funny one because you could always choose units. Which the speed of light is one. You know, we measure it in kilometers per second, and it's 186,000 or miles per second. It's 186,000 miles per second. But if we use different units, Then we could make it one. But you can make dimensionless ratios. So you could say why is the time scale set by the expansion of the universe so large compared to the timescale of a human life or so large compared to the timescale for a neutron to decay?”
2023-02-15 · Lex Fridman Podcast · #359 – Andrew Strominger: Black Holes, Quantum Gravity, and Theoretical Physics · IDENTIFIED FROM THE TRANSCRIPT · source
“We don't know what the heck is. It's really, really hard measurement, but they really know what they're doing. And we have no friggin idea why it's there. Another big mystery. Another reason it's fun to be a physicist. And if it is there, why should it be so small? Why should there be so little? Why should it have hid itself from us? Why shouldn't there enough be enough of it to substantially curve the space between us and the moon? Why did there have to be such a Small amount that only the crazy best astronomers in the world could find it.”
2023-02-15 · Lex Fridman Podcast · #359 – Andrew Strominger: Black Holes, Quantum Gravity, and Theoretical Physics · IDENTIFIED FROM THE TRANSCRIPT · source
“Dark energy is synonymous with positive cosmological constants. We think it's there. Because astronomers have told us it's there They know what they're doing.”
2023-02-15 · Lex Fridman Podcast · #359 – Andrew Strominger: Black Holes, Quantum Gravity, and Theoretical Physics · IDENTIFIED FROM THE TRANSCRIPT · source
“Precise enough measurements to determine this, and they believe that the answer is yes, the universe is now expanding. Eventually all the matter in it will be Expand it away, but it will continue to expand Because, well, they would call it the dark energy. Einstein would call it a cosmological constant. In any case, in the far future, matter will be expanded away and we'll be left with empty decitter space.”
2023-02-15 · Lex Fridman Podcast · #359 – Andrew Strominger: Black Holes, Quantum Gravity, and Theoretical Physics · IDENTIFIED FROM THE TRANSCRIPT · source
“The three simplest space-times are flat spacetime, which we call Minkowski spacetime, and negatively curved spacetime, antiditter space, and positively curved spacetime, desidter space. And so astronomers think that On large scales, even though for thousands of years we hadn't noticed it, beginning with Hubble. We started to notice that space time was curved. Space is expanding in time. It means that space-time is curved. And the nature of this curvature is affected by the matter in it because matter itself causes the curvature of spacetime. But as it expands, the matter gets more and more diluted, and one might ask when it's all diluted away is spacetime still curved? Astronomers believe they've done”
2023-02-15 · Lex Fridman Podcast · #359 – Andrew Strominger: Black Holes, Quantum Gravity, and Theoretical Physics · IDENTIFIED FROM THE TRANSCRIPT · source
“You have to step a couple, but even a If you have flat space and it's expanding in time. We could imagine we're sitting here in this room, good approximation, it's flat, but imagine we suddenly start getting further and further apart. Then space is flat. It's expanding, which means that space time is curved.”
2023-02-15 · Lex Fridman Podcast · #359 – Andrew Strominger: Black Holes, Quantum Gravity, and Theoretical Physics · IDENTIFIED FROM THE TRANSCRIPT · source
“Well, like the surface of this table. Is flat. Let me just give an intuitive explanation. Surface of the table is flat, but the surface of a basketball is curved. So the universe itself. Could be flat, like the surface of a table, or it could be curved like a basketball, which actually has a positive curvature. And then there's another kind of curvature called a negative curvature. Curvature can be even weirder because That kind of curvature I've just described is the curvature of space, but Einstein taught us that we really live in a spacetime continuum so we can have curvature in a way that mixes up space and time. And that's kind of hard to visualize”
2023-02-15 · Lex Fridman Podcast · #359 – Andrew Strominger: Black Holes, Quantum Gravity, and Theoretical Physics · IDENTIFIED FROM THE TRANSCRIPT · source
“Okay, so for thousands of years, you know, until the last half of the 20th, well, sorry, until the 20th century, we thought space-time was flat.”
2023-02-15 · Lex Fridman Podcast · #359 – Andrew Strominger: Black Holes, Quantum Gravity, and Theoretical Physics · IDENTIFIED FROM THE TRANSCRIPT · source
“Any area space. However, we've made sense of the holographic principle for black holes. We've made sense of the holographic principle. Called anti decitter space Could be thought of as a giant, as a black hole turned into a whole universe. And we don't really understand how to Talk about the holographic principle for. Either flat space, which we appear to live in, or asymptotically desider space, which distronomers tell us we actually live in as the universe continues to expand. So it's one of the huge problems in physics is to Apply or even formulate the holographic principle for more realistic, well, black holes are realistic, we see them. But yeah, in more general contexts.”
2023-02-15 · Lex Fridman Podcast · #359 – Andrew Strominger: Black Holes, Quantum Gravity, and Theoretical Physics · IDENTIFIED FROM THE TRANSCRIPT · source
“Well, I was just before I came here writing an introduction to a paper, and the first sentence was, As yet imprecisely defined holographic principle. Blah blah blah bl So nobody knows exactly what it is, but roughly speaking, it says just what we were alluding to, that really all the information that is in some volume of spacetime can be stored on the boundary of that region.”
2023-02-15 · Lex Fridman Podcast · #359 – Andrew Strominger: Black Holes, Quantum Gravity, and Theoretical Physics · IDENTIFIED FROM THE TRANSCRIPT · source
“Long hair. So Einstein's Black Cole is a short source black hole. They can't store information. Stuff goes in there and it just keeps flying and it goes in singularity and it's gone. However, and since there is not exact, it has corrections. String theory tells you what those corrections are. And so you should be able to find some way of some alternate way of describing the black hole that enables you To understand where the gigabytes are stored. So what Hawking and Beckenstein really did was they showed that physics is inconsistent unless a black hole can store a number of gigabytes proportional to its area divided by four times. Newton's constant times Planck's constant.”
2023-02-15 · Lex Fridman Podcast · #359 – Andrew Strominger: Black Holes, Quantum Gravity, and Theoretical Physics · IDENTIFIED FROM THE TRANSCRIPT · source
“Oh, okay. I'm going to ask you a question. I shouldn't try to memorize them and answer each one in order just to answer them.”
2023-02-15 · Lex Fridman Podcast · #359 – Andrew Strominger: Black Holes, Quantum Gravity, and Theoretical Physics · IDENTIFIED FROM THE TRANSCRIPT · source
“There isn't a sense in which a black hole can store some large number of gigabytes that quantum mechanics and gravity can't be consistent.”
2023-02-15 · Lex Fridman Podcast · #359 – Andrew Strominger: Black Holes, Quantum Gravity, and Theoretical Physics · IDENTIFIED FROM THE TRANSCRIPT · source
“Before my work with Quran, we couldn't do any better than Einstein and Churchill had done. Now, one of the puzzles If you look at the Hawking's headstone and also Boltzmann's headstone and you put them together, you get a formula. For their really central equations in 20th century physics. There are many equations that made it to headstones. And they're really central equations. And you put them together and you get a formula for the number of gigabytes in a black hole Now in Schwartzhild's description. Black hole is literally a hole in space, and there's no place to store the gigabytes. And it's not too hard to, and this really was Wheeler and Beckenstein and Wheeler, Beckenstein and Hawking. To come to the conclusion that”
2023-02-15 · Lex Fridman Podcast · #359 – Andrew Strominger: Black Holes, Quantum Gravity, and Theoretical Physics · IDENTIFIED FROM THE TRANSCRIPT · source
“Mathematically It was all correct, but But mathematically clumsy, but it often happens That in all kinds of branches of physics that People start working on it really hard and they sort of dream about it and live it and breathe it and they begin to see inner relationships and they see a beauty that Is really there. They're not deceived. They're really seeing something that exists. But if you just kind of look at it, you can't grasp it all in the beginning. So Understanding of string theory in In 1985, it was almost all about Weekly coupled waves of strings colliding and so on. We didn't know how to describe a big thing like a black hole in string theory. Of course, we could show that strings in theory in some limit reproduced Einstein's theory of general relativity. And corrected it, but we couldn't do any better with black holes than”
2023-02-15 · Lex Fridman Podcast · #359 – Andrew Strominger: Black Holes, Quantum Gravity, and Theoretical Physics · IDENTIFIED FROM THE TRANSCRIPT · source
“Yeah. So that is a very interesting story. I was Interested in black holes before I was interested in string theory. I was sort of a reluctance string theorist in the beginning. I thought I had to learn it because people were talking about it. But once I studied it, I grew to love it. First, I did it in a sort of dutiful way. These people say they've claimed quantum gravity. I ought to read their papers at least. And then the more I read them, the more interested I got and I begin to see, you know, they. They phrased it in a very clumsy way, the description of string theory was very clumsy.”
2023-02-15 · Lex Fridman Podcast · #359 – Andrew Strominger: Black Holes, Quantum Gravity, and Theoretical Physics · IDENTIFIED FROM THE TRANSCRIPT · source
“Now it really means something. And I would bet the farm on the... On the guess that 100 years from now, string theory will be viewed as a stepping stone towards a greater understanding of nature. And it would, I mean, another thing that I didn't mention about string theory is, of course, we know. Solved the infinities problem, and then we later learned that it also solved Hawking's puzzle about What's inside of a black hole? You put in one assumption, you get five things out. Somehow you're doing something right. Probably not everything, but there's some good signposts. And there have been a lot of good signposts like that.”
2023-02-15 · Lex Fridman Podcast · #359 – Andrew Strominger: Black Holes, Quantum Gravity, and Theoretical Physics · IDENTIFIED FROM THE TRANSCRIPT · source
“And it's also true of Einstein's theory of general relativity. He had the wrong version of it in 1914, and he was missing some pieces. And you wouldn't say that his early version was right or wrong. He'd understood the equivalence principle. He'd understood spacetime curvature. He just didn't have everything. I mean, technically you would have to say it was wrong. And technically you would have to say Yang and Mills were wrong. And I guess in that sense. I would believe just. Odds are We always keep finding new wrinkles. Odds are we're going to find new wrinkles in string theory, and technically what we call string theory now isn't quite right.”
2023-02-15 · Lex Fridman Podcast · #359 – Andrew Strominger: Black Holes, Quantum Gravity, and Theoretical Physics · IDENTIFIED FROM THE TRANSCRIPT · source
“I think it's a Logical error to think that string theory is either right or wrong or dead or alive. What it is is a stepping stone. And an analogy I like to draw is Yang Mill's theory. Which I mentioned a few minutes ago in the context of standard model. Yang Mill's theory was discovered by Yang and Mills in the fifties. And they thought that the symmetry of Yang and Mills theory. Described the relationship between the proton and the neutron. That's why they invented it. That turned out to be completely wrong. It does, however, describe everything else in the standard model. And it had a kind of inevitability. They had some of the right pieces, but not the other ones. They didn't have it quite in the right context. And it had an inevitability to it and it eventually sort of found its place.”
2023-02-15 · Lex Fridman Podcast · #359 – Andrew Strominger: Black Holes, Quantum Gravity, and Theoretical Physics · IDENTIFIED FROM THE TRANSCRIPT · source
“No, it's a very interesting feature of the real world that it isn't parody invariant. In string theory, it was thought could not tolerate that And then it was learned in the mid-80s that not only could it tolerate that, but if you did things in the right way, you could construct a world out. Involving strings that reconciled quantum mechanics and general relativity, which looked more or less like the world that We live in. And now that isn't to say that string theory predicted our world. It just meant that it was consistent, that the hypothesis that string theory describes our world can't be ruled out from the get-go. And it is also the only proposal for a complete theory that would describe our world, still Nobody will believe it. Until there's some kind of direct experiment. And I don't even believe it myself.”
2023-02-15 · Lex Fridman Podcast · #359 – Andrew Strominger: Black Holes, Quantum Gravity, and Theoretical Physics · IDENTIFIED FROM THE TRANSCRIPT · source
“And you look in the mirror across the bar. The universe that you see in the mirror is not identical. You would be able to tell if you show your... Lady in the bar a photograph that shows both the mirror and you. If she's smart enough, she'll be able to tell which one is the real world and which one is you. Now she would have to do some very precise measurements And if the photograph was too grainy, it might not be possible. But in principle, it's possible.”
2023-02-15 · Lex Fridman Podcast · #359 – Andrew Strominger: Black Holes, Quantum Gravity, and Theoretical Physics · IDENTIFIED FROM THE TRANSCRIPT · source
“Now, at the same time, it was believed then that string theory was an interesting sort of toy model for putting quantum mechanics in general relativity together on paper. But that it couldn't describe some of the very idiosyncratic phenomena that pertain to our own universe. In particular, the form of so-called parity violation.”
2023-02-15 · Lex Fridman Podcast · #359 – Andrew Strominger: Black Holes, Quantum Gravity, and Theoretical Physics · IDENTIFIED FROM THE TRANSCRIPT · source
“Never described it this way before, but it's actually scientifically accurate. But if you throw strings at each other, it's a little more friendly. One thing I can't explain is how wonderfully precise will the mathematics is that goes into describing string theory. We don't just wave our hands and throw strings around. There's some very compelling mathematical equations that describe it. What was realized in the early 70s is that if you replace particles by strings, these infinities go away and you get a consistent Theory of gravity without the infinities That may sound a little trivial, but at that point it already been. 15 years that people had been searching around for any kind of theory that could do this. And it was actually found kind of By accident. And there are a lot of accidental discoveries in this subject.”
2023-02-15 · Lex Fridman Podcast · #359 – Andrew Strominger: Black Holes, Quantum Gravity, and Theoretical Physics · IDENTIFIED FROM THE TRANSCRIPT · source
“Well, you know, if you hit a particle, If there were a particle on this table, a big one, and you hit it, you might bruise yourself. But if there was a string on the table, you would probably just push it around. And the source of the infinities in quantum field theories that would particles hit each other, it's a little bit of a... A jarring effect.”
2023-02-15 · Lex Fridman Podcast · #359 – Andrew Strominger: Black Holes, Quantum Gravity, and Theoretical Physics · IDENTIFIED FROM THE TRANSCRIPT · source
“Well, the basic idea which emerged in the early 70s was that if you You take the notion of a particle and you literally. Replace it by a little loop of string. Strings are sort of softer than particles”
2023-02-15 · Lex Fridman Podcast · #359 – Andrew Strominger: Black Holes, Quantum Gravity, and Theoretical Physics · IDENTIFIED FROM THE TRANSCRIPT · source
“Sort of the one fully consistent model that we have that reconciles, that sort of tames gravity and reconciles it with quantum mechanics. Is string theory and its cousins. And we don't know what or if in any sense string theory describes the world, the physical world, but we do know that it Is a consistent reconciliation of quantum mechanics in general relativity. And moreover, one which Which is able to incorporate particles and forces like the ones we see around us. So it hasn't been ruled out as an actual sort of unified theory of nature. But there also isn't a In my view, some people would disagree with me. But there isn't a reasonable possibility that we would be able to do an experiment in the foreseeable future, which would be sort of a yes or no to string theory.”
2023-02-15 · Lex Fridman Podcast · #359 – Andrew Strominger: Black Holes, Quantum Gravity, and Theoretical Physics · IDENTIFIED FROM THE TRANSCRIPT · source
“Good luck, thank you They all fall under that rubric. Gravity will not put that suit on. So the force of gravity cannot be tamed by the same renormalizable quantum field theory to which all the other forces so eagerly submitted.”
2023-02-15 · Lex Fridman Podcast · #359 – Andrew Strominger: Black Holes, Quantum Gravity, and Theoretical Physics · IDENTIFIED FROM THE TRANSCRIPT · source