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'''Eric Weinstein: A Conversation''' was a livestream of Into the Impossible hosted by [[Brian Keating]], dicussing [[Geometric Unity]] with guest [[Eric Weinstein]].
 
'''Eric Weinstein: A Conversation''' was a livestream of Into the Impossible, hosted by [[Brian Keating]] with guest [[Eric Weinstein]], discussing [[Geometric Unity]].


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===Introduction===
===Introduction===


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00:06:23<br>
00:06:23<br>
'''Brian Keating:''' And certainly, I'll have on Michio Kaku next week on the Into the Impossible podcast, and I hope maybe we'll get a cameo from you. But in his book, he writes something very provocative. And he says at the end of his book, he quotes those lines from Stephen Hawking, which is kind of like this infinite regress, which kind of strains credulity, so to speak. But he says, at one point he says, "It's not fair to test String Theory, to ask to test String Theory experimentally, because we don't know its final principles." But the same, I claim, could have been said about quantum mechanics. Do we know the final principles of quantum mechanics? Does that immunize it from experimental test?
'''Brian Keating:''' And certainly, I'll have on Michio Kaku next week on the Into the Impossible podcast, and I hope maybe we'll get a cameo from you. But in his book, he writes something very provocative. And he says at the end of his book, he quotes those lines from Stephen Hawking, which is kind of like this infinite regress, which kind of strains credulity, so to speak. But he says, at one point he says, "It's not fair to test string theory, to ask to test string theory experimentally, because we don't know its final principles." But the same, I claim, could have been said about quantum mechanics. Do we know the final principles of quantum mechanics? Does that immunize it from experimental test?


00:07:10<br>
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00:07:42<br>
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One of the reasons String Theory got such a boost is that the brilliance of the initial volunteers for the first string revolution around 1984 were so good that we were inclined to give them a huge pass, at least at first. And then, we have this differential application where the string theorists become paradoxically the most persnickety about what is a prediction, because they don't want to give up the fact that they aren't really making predictions. So if you, for example, predict internal quantum numbers of the next particles to be found, but you don't come up with an energy threshold, and you don't say what will invalidate your theory, they get angry. Because, in fact, what we've done is we've given them an asymmetric relationship with the scientific method through special pleading.  
One of the reasons string theory got such a boost is that the brilliance of the initial volunteers for the first string revolution around 1984 were so good that we were inclined to give them a huge pass, at least at first. And then, we have this differential application where the string theorists become paradoxically the most persnickety about what is a prediction, because they don't want to give up the fact that they aren't really making predictions. So if you, for example, predict internal quantum numbers of the next particles to be found, but you don't come up with an energy threshold, and you don't say what will invalidate your theory, they get angry. Because, in fact, what we've done is we've given them an asymmetric relationship with the scientific method through special pleading.  


00:08:35<br>
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00:11:29<br>
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So I think that you have a situation by which new ideas are always not properly instantiated, and the community that is constantly trying to make sure that... I think that the idea is that people are foolish enough to play this game with the most aggressive members of the community, because the implication is if you won't come up with a testable prediction that invalidates your theory, you're anti scientific and we have no time for this. And so people, well like, you know, with the \(\text{SU}(5)\) theory, they immediately said okay, well it predicts proton decay. Well, grand unification is a larger idea, and some versions and instantiations do predict proton decay, and some do not. So what are you going to say about that? I think that the problem is that we're not in an adult phase where we've faced up to the fact that we have almost 50 years of stagnation, and what you're seeing with this proliferation of new claimants to have fundamental theories is, in part, that String Theory has finally weakened itself, and the aging of the particular cohort—which is Baby Boomers, who are the String Theory proponents—they've gotten weak enough that effectively other people feel emboldened. And I think Stephen Wolfram said this recently, that in a previous era, he would have expected to have been attacked. But we've been waiting around for so long that perhaps the political economy of unification and wild ideas has changed somewhat.
So I think that you have a situation by which new ideas are always not properly instantiated, and the community that is constantly trying to make sure that... I think that the idea is that people are foolish enough to play this game with the most aggressive members of the community, because the implication is if you won't come up with a testable prediction that invalidates your theory, you're anti scientific and we have no time for this. And so people, well like, you know, with the <math>\text{SU}(5)</math> theory, they immediately said okay, well it predicts proton decay. Well, grand unification is a larger idea, and some versions and instantiations do predict proton decay, and some do not. So what are you going to say about that? I think that the problem is that we're not in an adult phase where we've faced up to the fact that we have almost 50 years of stagnation, and what you're seeing with this proliferation of new claimants to have fundamental theories is, in part, that string theory has finally weakened itself, and the aging of the particular cohort—which is Baby Boomers, who are the string theory proponents—they've gotten weak enough that effectively other people feel emboldened. And I think Stephen Wolfram said this recently, that in a previous era, he would have expected to have been attacked. But we've been waiting around for so long that perhaps the political economy of unification and wild ideas has changed somewhat.


===Approaches to a Theory of Everything===
===Approaches to a Theory of Everything===
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00:27:59<br>
00:27:59<br>
'''Eric Weinstein:''' So effectively, what I'm asking is, can a manifold \(X^4\) produce the baroque structure of the Standard Model? Now—and gravity. And if you think back to the famous mug popular in the CERN gift shop, there really isn't that much going on in the Standard Model if you group terms in particular ways. But there's a lot of weirdness. Why the Lorentz group, why \(\text{SU}(3) \times \text{SU}(2) \times \text{U}(1)\) for the internal symmetries generating the forces, why three families? I thought that something that many younger viewers may not be aware of is that things really changed around 1983, '84. If you think about the original anomaly cancellation of Green and Schwarz in 1984, I believe, you could ask what was physics like right before that moment? And I think it's absolutely shocking, because we don't realize the extent to which the string theorists really redefined what the major problems in physics were. I think most people in the post-string era somehow believe that the major issue is quantum gravity. And I don't really, I just find it astounding, because that's really what the string theorists were selling.  
'''Eric Weinstein:''' So effectively, what I'm asking is, can a manifold <math>X^4</math> produce the baroque structure of the Standard Model? Now—and gravity. And if you think back to the famous mug popular in the CERN gift shop, there really isn't that much going on in the Standard Model if you group terms in particular ways. But there's a lot of weirdness. Why the Lorentz group, why <math>\text{SU}(3) \times \text{SU}(2) \times \text{U}(1)</math> for the internal symmetries generating the forces, why three families? I thought that something that many younger viewers may not be aware of is that things really changed around 1983, '84. If you think about the original anomaly cancellation of Green and Schwarz in 1984, I believe, you could ask what was physics like right before that moment? And I think it's absolutely shocking, because we don't realize the extent to which the string theorists really redefined what the major problems in physics were. I think most people in the post-string era somehow believe that the major issue is quantum gravity. And I don't really, I just find it astounding, because that's really what the string theorists were selling.  


00:29:34<br>
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00:30:32<br>
00:30:32<br>
Okay, so what are his big questions? Why this particular structure for the families? In particular, why flavor chiral with left- and right-handed particles being treated differently by the weak force, rather than say vectorlike ones left and right transformable into being treated the same? Next, why three families? That generalizes Robbie's famous question "Who ordered that?" as if the universe was a Jewish deli, commenting on the muon. How many sets of Higgs bosons are there? We talk about the Higgs boson, but maybe there are multiple sets and there are multiple different scales at which symmetry is broken and mass is imparted through soft mass mechanisms. Lastly, why \(\text{SU}(3) \times \text{SU}(2) \times \text{U}(1)\)? Remember, \(\text{SU}(3)\) is the color force for the strong force, but \(\text{SU}(2)\) here is weak isospin, which has not yet become the W and Z's. And this \(\text{U}(1)\) is weak hypercharge, which has not yet become electromagnetism through symmetry breaking. And in some sense, I just feel sort of sad that we don't think of these as questions because we know not to ask them.  
Okay, so what are his big questions? Why this particular structure for the families? In particular, why flavor chiral with left- and right-handed particles being treated differently by the weak force, rather than say vectorlike ones left and right transformable into being treated the same? Next, why three families? That generalizes Robbie's famous question "Who ordered that?" as if the universe was a Jewish deli, commenting on the muon. How many sets of Higgs bosons are there? We talk about the Higgs boson, but maybe there are multiple sets and there are multiple different scales at which symmetry is broken and mass is imparted through soft mass mechanisms. Lastly, why <math>\text{SU}(3) \times \text{SU}(2) \times \text{U}(1)</math>? Remember, <math>\text{SU}(3)</math> is the color force for the strong force, but <math>\text{SU}(2)</math> here is weak isospin, which has not yet become the W and Z's. And this <math>\text{U}(1)</math> is weak hypercharge, which has not yet become electromagnetism through symmetry breaking. And in some sense, I just feel sort of sad that we don't think of these as questions because we know not to ask them.  


00:31:42<br>
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00:33:38<br>
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'''Eric Weinstein:''' This is very unpleasant to have to say this, but I think that we are talking about a great era with heroes. The top hero among them is undoubtedly Ed Witten. But I do believe that Yang and Simons, I think Yang and Simon's discovery of Ehresmannian bundle theory, which has a precursor—and I'm blanking on the gentleman's name (Robert Hermann), all the self published books from from the '60s. It'll come to me, but there was a man in Boston who probably got there a little bit earlier. And then I would say that you have accidental physicists. Dan Quillen, for example, did a huge amount to talk about connections on determinant bundles and the like, which come out of various quantization procedures, particularly with Berezin integration of fermion sectors. So I think that a lot of things got done to shore up what we do to mature input into a quantum theory. It just, it wasn't physics, per se. It was sort of the mathematics of physics. And I think that that was very frustrating, which is, you know, it's sort of, to physicists it's yeoman's work. They wanted to go to Stockholm, and they ended up winning the first Fields Medal won by a physicist, and I think—it's weird. It's like, what is your time? Your time is whatever it is that can be done. And they thought their time was to quantize gravity. "Well guess again," nature said, "we have something incredibly important." So I feel like I'm trying to rescue their legacy. They want to go down as string theorists for the most part. And they want to say that String Theory was the most successful of any claimant, even though it wasn't very successful. And, my feeling is—
'''Eric Weinstein:''' This is very unpleasant to have to say this, but I think that we are talking about a great era with heroes. The top hero among them is undoubtedly Ed Witten. But I do believe that Yang and Simons, I think Yang and Simon's discovery of Ehresmannian bundle theory, which has a precursor—and I'm blanking on the gentleman's name (Robert Hermann), all the self published books from from the '60s. It'll come to me, but there was a man in Boston who probably got there a little bit earlier. And then I would say that you have accidental physicists. Dan Quillen, for example, did a huge amount to talk about connections on determinant bundles and the like, which come out of various quantization procedures, particularly with Berezin integration of fermion sectors. So I think that a lot of things got done to shore up what we do to mature input into a quantum theory. It just, it wasn't physics, per se. It was sort of the mathematics of physics. And I think that that was very frustrating, which is, you know, it's sort of, to physicists it's yeoman's work. They wanted to go to Stockholm, and they ended up winning the first Fields Medal won by a physicist, and I think—it's weird. It's like, what is your time? Your time is whatever it is that can be done. And they thought their time was to quantize gravity. "Well guess again," nature said, "we have something incredibly important." So I feel like I'm trying to rescue their legacy. They want to go down as string theorists for the most part. And they want to say that string theory was the most successful of any claimant, even though it wasn't very successful. And, my feeling is—


00:35:39<br>
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00:35:44<br>
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'''Eric Weinstein:''' Well, yes, I feel like we can say that it's not very successful, because they gave us the terms in which we should evaluate it. You know, I remember being told "Give us 10 years, we'll have the whole thing cleaned up. Don't worry your pretty little head, we'll be fine," or, "We have a finite number of theories to check." And then lo and behold, there's a continuum, or why is it called String Theory when there are branes involved? And it was because if you asked once upon a time, they'd say, "Well, it's not like mathematicians think about higher-dimensional objects beyond strings." There was an explanation for why there were no branes. And, you know, that—yes, String Theory has failed in its own terms. Now is it salvageable, are there pivots beyond? Yeah, sure. I'm not saying that they didn't stumble on a tremendous amount of structure, maybe that structure ultimately carries the day. But I do think that the idea that they're entitled to this many pivots without having to become self-reflective is preposterous. And I think many people feel that way, and they know that they might pay for such a statement with their career. And since I've prepaid, it falls to people like me and to you, perhaps, to say look, the string theorists weren't able to confront their failure.
'''Eric Weinstein:''' Well, yes, I feel like we can say that it's not very successful, because they gave us the terms in which we should evaluate it. You know, I remember being told "Give us 10 years, we'll have the whole thing cleaned up. Don't worry your pretty little head, we'll be fine," or, "We have a finite number of theories to check." And then lo and behold, there's a continuum, or why is it called string theory when there are branes involved? And it was because if you asked once upon a time, they'd say, "Well, it's not like mathematicians think about higher-dimensional objects beyond strings." There was an explanation for why there were no branes. And, you know, that—yes, string theory has failed in its own terms. Now is it salvageable, are there pivots beyond? Yeah, sure. I'm not saying that they didn't stumble on a tremendous amount of structure, maybe that structure ultimately carries the day. But I do think that the idea that they're entitled to this many pivots without having to become self-reflective is preposterous. And I think many people feel that way, and they know that they might pay for such a statement with their career. And since I've prepaid, it falls to people like me and to you, perhaps, to say look, the string theorists weren't able to confront their failure.


====The Grand Nature of Physics====
====The Grand Nature of Physics====
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00:38:30<br>
00:38:30<br>
'''Brian Keating:''' Every time you gotta pick up your dry cleaning—but when we lose sight of it, I find with my colleagues, and I'll speak, because I doubt many of them are listening. I really don't feel like they're that curious, intellectually. I think it is a job. I think their their job is the dry cleaning. And I can sort of prove that in some ways, because I often hear them say things like well, Eric is a showman, he's a podcaster. He's a host, and he's had training, and he's very smooth, and he can speak well. And I say "Well, do you think he do you think he emerged from the womb like that? And by the way, Mister or Missus Professor, Doctor Professor, you have got a lot of training in quantum field theory and String Theory yourself. That was presumably a challenge for you. You didn't emerge womb-like, you know, from the caverns of the womb, knowing quantum field theory, so you had to work at that." So it's all about prioritization. Why do you think physicists aren't more troubled by the lack of progress, that our mutual friend Sabine has pointed out, in the last 50 years, at least in fundamental physics? My colleagues will rightfully point out tremendous advances in cosmological theory, in condensed matter theory, etc. But why isn't that more troubling? I think the answer is we're not that curious. You have a vision of us that's maybe more more refined than I think we deserve, and that's because you're not a professional physicist.
'''Brian Keating:''' Every time you gotta pick up your dry cleaning—but when we lose sight of it, I find with my colleagues, and I'll speak, because I doubt many of them are listening. I really don't feel like they're that curious, intellectually. I think it is a job. I think their their job is the dry cleaning. And I can sort of prove that in some ways, because I often hear them say things like well, Eric is a showman, he's a podcaster. He's a host, and he's had training, and he's very smooth, and he can speak well. And I say "Well, do you think he do you think he emerged from the womb like that? And by the way, Mister or Missus Professor, Doctor Professor, you have got a lot of training in quantum field theory and string theory yourself. That was presumably a challenge for you. You didn't emerge womb-like, you know, from the caverns of the womb, knowing quantum field theory, so you had to work at that." So it's all about prioritization. Why do you think physicists aren't more troubled by the lack of progress, that our mutual friend Sabine has pointed out, in the last 50 years, at least in fundamental physics? My colleagues will rightfully point out tremendous advances in cosmological theory, in condensed matter theory, etc. But why isn't that more troubling? I think the answer is we're not that curious. You have a vision of us that's maybe more more refined than I think we deserve, and that's because you're not a professional physicist.


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00:43:38<br>
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'''Eric Weinstein:''' You have \(X^n\) for a manifold of n-dimensions. Make it orientable with a particular orientation, make it have a unique spin structure, whatever you need to do to set it up as a decent manifold. Replace that manifold, momentarily, by the bundle of all metric tensors pointwise on the same space. And that way, spacetime would be a particular section of that bundle. Let me see if I can find a...
'''Eric Weinstein:''' You have <math>X^n</math> for a manifold of n-dimensions. Make it orientable with a particular orientation, make it have a unique spin structure, whatever you need to do to set it up as a decent manifold. Replace that manifold, momentarily, by the bundle of all metric tensors pointwise on the same space. And that way, spacetime would be a particular section of that bundle. Let me see if I can find a...


00:44:19<br>
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00:44:43<br>
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Okay. So right here, I've got a 4-dimensional manifold. Imagine that I'm interested in looking at the bundle of all pointwise metrics, which is going to be—if the base space is 4-dimensional, make \(4 = n\)—it will be of dimension \(n^{\frac{n^2 + 3n}{2}}\). So \(4^2\) is 16, plus \(3n\), \(3 \times 4 = 12\). So \(16 + 12 = 28\), divided by 2 is 14. If you have a \((1,3)\) metric downstairs, I believe that you are naturally courting a \((7, 7)\) or \((9, 5)\) metric upstairs. And that is the first step in GU, which is that you replace a single space with one particular metric by a pair of spaces, a total space and a base space of a fiber bundle—this is in the strong form of GU—and physics mostly happens upstairs on the bundle of all metrics, not downstairs on the particular space that got you started.  
Okay. So right here, I've got a 4-dimensional manifold. Imagine that I'm interested in looking at the bundle of all pointwise metrics, which is going to be—if the base space is 4-dimensional, make <math>4 = n</math>—it will be of dimension <math>n^{\frac{n^2 + 3n}{2}}</math>. So <math>4^2</math> is 16, plus <math>3n</math>, <math>3 \times 4 = 12</math>. So <math>16 + 12 = 28</math>, divided by 2 is 14. If you have a <math>(1,3)</math> metric downstairs, I believe that you are naturally courting a <math>(7, 7)</math> or <math>(9, 5)</math> metric upstairs. And that is the first step in GU, which is that you replace a single space with one particular metric by a pair of spaces, a total space and a base space of a fiber bundle—this is in the strong form of GU—and physics mostly happens upstairs on the bundle of all metrics, not downstairs on the particular space that got you started.  


00:46:02<br>
00:46:02<br>
Here, \(U^4\) is an open set in \(X^4\). Okay, so effectively, what are we saying? We're saying that physics is going to dance on not only the space of four coordinates, typically \(x\), \(y\), \(z\), and \(t\), or thinking in a coordinate-independent fashion, simply four parameters, it's also going to dance on the space of rulers and protractors at every given point. And so that structure is the beginning of GU, and then you can recover Einstein, spacetime, by simply saying that if I have a section of that bundle, that's a spacetime metric.
Here, <math>U^4</math> is an open set in <math>X^4</math>. Okay, so effectively, what are we saying? We're saying that physics is going to dance on not only the space of four coordinates, typically <math>x</math>, <math>y</math>, <math>z</math>, and <math>t</math>, or thinking in a coordinate-independent fashion, simply four parameters, it's also going to dance on the space of rulers and protractors at every given point. And so that structure is the beginning of GU, and then you can recover Einstein, spacetime, by simply saying that if I have a section of that bundle, that's a spacetime metric.


00:46:55<br>
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00:47:03<br>
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'''Eric Weinstein:''' Well, I gave three forms of GU. One form is the trivial form, in which you have the second space \(Y\) the same as the first space \(X\). That means that you can easily recover everything Einstein did as a form of Geometric Unity by trivially making the observerse irrelevant. You're just repeating the same space twice, and you've got one map between them called the identity, and now you're back in your old world. So without loss of generality, you cover that. Another one is a completely general world, which I think—What did we call it here... Well, I called the middle one the Einsteinian one, where you actually make the second space \(Y\) the space of metrics. And that's the one that I think is the most interesting, but I don't want to box myself in, because I don't want to play these games of Simon's "You said this," or "You said that." You know, I can play the lawyerly game as well as anyone if that's what we are really trying to do. I thought we were trying to do physics.  
'''Eric Weinstein:''' Well, I gave three forms of GU. One form is the trivial form, in which you have the second space <math>Y</math> the same as the first space <math>X</math>. That means that you can easily recover everything Einstein did as a form of Geometric Unity by trivially making the observerse irrelevant. You're just repeating the same space twice, and you've got one map between them called the identity, and now you're back in your old world. So without loss of generality, you cover that. Another one is a completely general world, which I think—What did we call it here... Well, I called the middle one the Einsteinian one, where you actually make the second space <math>Y</math> the space of metrics. And that's the one that I think is the most interesting, but I don't want to box myself in, because I don't want to play these games of Simon's "You said this," or "You said that." You know, I can play the lawyerly game as well as anyone if that's what we are really trying to do. I thought we were trying to do physics.  


00:48:19<br>
00:48:19<br>
The thing that I'm trying to get at here is that I believe you and I are somehow having a pullback of a 14-dimensional conversation right now. My guess is that there is a space, with a \((7, 7)\) metric, probably more likely than a \((9, 5)\) metric, on 14 dimensions, where not only are the waves that are relevant going over the original coordinates \(x_1\) through \(x_4\), they're also going through four ruler coordinates on the tangent bundle of the original \(x\) coordinates. So there are 4 rulers to measure the 4 directions, and then there are also going to be 6 protractors. Because if you name the directions John, Paul, George, and Ringo, you'd have John with Paul, John with George, John with Ringo, Paul with George, Paul with Ringo, George with Ringo. Right? And so, those 6 protractors are actually degrees of freedom for the fields, and the fields live on that space.  
The thing that I'm trying to get at here is that I believe you and I are somehow having a pullback of a 14-dimensional conversation right now. My guess is that there is a space, with a <math>(7, 7)</math> metric, probably more likely than a <math>(9, 5)</math> metric, on 14 dimensions, where not only are the waves that are relevant going over the original coordinates <math>x_1</math> through <math>x_4</math>, they're also going through four ruler coordinates on the tangent bundle of the original <math>x</math> coordinates. So there are 4 rulers to measure the 4 directions, and then there are also going to be 6 protractors. Because if you name the directions John, Paul, George, and Ringo, you'd have John with Paul, John with George, John with Ringo, Paul with George, Paul with Ringo, George with Ringo. Right? And so, those 6 protractors are actually degrees of freedom for the fields, and the fields live on that space.  


00:49:30<br>
00:49:30<br>
Then the question is why do we perceive 4 dimensions and complicated fields? And the answer is pullbacks. When you have a metric, you have a map from the base space into the total space, so Einstein—we don't think of it this way—is embedding a lifeless space which is without form, \(X^4\), into a 14-dimensional space before Geometric Unity ever even got on the scene, and giving him the ability to pull back information, which he may say is only happening on that tiny little slice, that little filament that is the 4-dimensional manifold swimming in a 14-dimensional world with a 10-dimensional normal bundle. But why not imagine that actually the fields are actually spread out over all 14 dimensions, and then all you're seeing is pullback information downstairs. Now the metric is doing something new that it wasn't doing before. It's pulling back data that is natural to \(Y^{14}\) as if it was natural on X, but I call this invasive fields versus native fields, just because some species are invasive, and some species are endemic, or native. The interesting thing about the bundle of all spinors, sorry, the bundle of all metrics, is that it almost has a metric on it. I don't know if I've ever heard anyone mention this.
Then the question is why do we perceive 4 dimensions and complicated fields? And the answer is pullbacks. When you have a metric, you have a map from the base space into the total space, so Einstein—we don't think of it this way—is embedding a lifeless space which is without form, <math>X^4</math>, into a 14-dimensional space before Geometric Unity ever even got on the scene, and giving him the ability to pull back information, which he may say is only happening on that tiny little slice, that little filament that is the 4-dimensional manifold swimming in a 14-dimensional world with a 10-dimensional normal bundle. But why not imagine that actually the fields are actually spread out over all 14 dimensions, and then all you're seeing is pullback information downstairs. Now the metric is doing something new that it wasn't doing before. It's pulling back data that is natural to <math>Y^{14}</math> as if it was natural on X, but I call this invasive fields versus native fields, just because some species are invasive, and some species are endemic, or native. The interesting thing about the bundle of all spinors, sorry, the bundle of all metrics, is that it almost has a metric on it. I don't know if I've ever heard anyone mention this.


00:51:02<br>
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00:51:09<br>
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'''Eric Weinstein:''' So in other words, assume that you haven't chosen a metric on \(X^4\). What you have then is you have a 10-dimensional subspace along the fibers, which we can call the vertical space. And that 10-dimensional space at every point upstairs, every point is, in fact, a metric downstairs, being by construction. So that means it imparts a metric on 10-dimensional vectors along the fibers. Now those are symmetric 2-tensors, effectively, because it's a space of metrics. You have this really interesting space here, call that \(V\). Well that \(V\) has a Frobenius metric based on the particular metric at which you are looking at the tangent space, which has got a 10-dimensional subspace picked out. If you map that 10-dimensional subspace into the 14-dimensional tangent space of the manifold \(Y^{14}\), you can take a quotient and call that \(H\). And that \(H\) will also have a metric because it's isomorphic to the dual of the pullback of the cotangent bundle downstairs. And the cotangent bundle has a metric because at that point that you picked in \(Y^{14}\) is itself a metric downstairs.  
'''Eric Weinstein:''' So in other words, assume that you haven't chosen a metric on <math>X^4</math>. What you have then is you have a 10-dimensional subspace along the fibers, which we can call the vertical space. And that 10-dimensional space at every point upstairs, every point is, in fact, a metric downstairs, being by construction. So that means it imparts a metric on 10-dimensional vectors along the fibers. Now those are symmetric 2-tensors, effectively, because it's a space of metrics. You have this really interesting space here, call that <math>V</math>. Well that <math>V</math> has a Frobenius metric based on the particular metric at which you are looking at the tangent space, which has got a 10-dimensional subspace picked out. If you map that 10-dimensional subspace into the 14-dimensional tangent space of the manifold <math>Y^{14}</math>, you can take a quotient and call that <math>H</math>. And that <math>H</math> will also have a metric because it's isomorphic to the dual of the pullback of the cotangent bundle downstairs. And the cotangent bundle has a metric because at that point that you picked in <math>Y^{14}</math> is itself a metric downstairs.  


00:52:40<br>
00:52:40<br>
So now you've got a metric on \(V\), you've got a metric on \(H^*\), and you just don't know how \(H^*\) becomes the complement to \(V\) and \(T\). That's the only piece of data you're missing for a metric. So you've got a 4-metric, you've got a 10-metric, the 10-metric is sitting inside of the tangent. The 4-metric is naturally sitting inside of the cotangent bundle. They're weirdly complementary, you've got a metric on the nose but for one piece of data, which we call a connection. So up to a connection, the manifold \(Y^{14}\) has a metric on it without ever having chosen a metric because it's made out of metric data.
So now you've got a metric on <math>V</math>, you've got a metric on <math>H^*</math>, and you just don't know how <math>H^*</math> becomes the complement to <math>V</math> and <math>T</math>. That's the only piece of data you're missing for a metric. So you've got a 4-metric, you've got a 10-metric, the 10-metric is sitting inside of the tangent. The 4-metric is naturally sitting inside of the cotangent bundle. They're weirdly complementary, you've got a metric on the nose but for one piece of data, which we call a connection. So up to a connection, the manifold <math>Y^{14}</math> has a metric on it without ever having chosen a metric because it's made out of metric data.


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00:53:43<br>
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'''Eric Weinstein:''' Well, that's true for any—no, it's true for the spin representation. It's not true generically, for any representation. But it allows you to build the spinors on what should be the total space, because now you've got a 4-dimensional... So, I think it's here at 3.12. If the spinors of a sum are the tensor products of the spinors on the summands, and I create a new bundle, which is the 10-dimensional vertical bundle inside the tangent bundle direct sum the 4-dimensional bundle inside the cotangent bundle, then the spinors on that thing—which is isomorphic and in fact semi-canonically isomorphic to both the tangent bundle and the cotangent bundle, being chimeric, it's isomorphic, but it's not fully canonically. It's only semi-canonically. So spinors on that will be identifiable with the spinors on \(Y\) as soon as you have a connection that completes this and makes it fully canonically isomorphic.  
'''Eric Weinstein:''' Well, that's true for any—no, it's true for the spin representation. It's not true generically, for any representation. But it allows you to build the spinors on what should be the total space, because now you've got a 4-dimensional... So, I think it's here at 3.12. If the spinors of a sum are the tensor products of the spinors on the summands, and I create a new bundle, which is the 10-dimensional vertical bundle inside the tangent bundle direct sum the 4-dimensional bundle inside the cotangent bundle, then the spinors on that thing—which is isomorphic and in fact semi-canonically isomorphic to both the tangent bundle and the cotangent bundle, being chimeric, it's isomorphic, but it's not fully canonically. It's only semi-canonically. So spinors on that will be identifiable with the spinors on <math>Y</math> as soon as you have a connection that completes this and makes it fully canonically isomorphic.  


00:54:49<br>
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00:59:04<br>
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'''Brian Keating:''' Yeah. I mean, you might also say oh, there's 26 dimensions in heterotic String Theory. That can't be right. No, it's only 10, or 11, or 5-brane, m-brane theory. I want to ask another question, which is frequently used in criticisms, both anonymous and nonymous, which is that this doesn't—
'''Brian Keating:''' Yeah. I mean, you might also say oh, there's 26 dimensions in heterotic string theory. That can't be right. No, it's only 10, or 11, or 5-brane, m-brane theory. I want to ask another question, which is frequently used in criticisms, both anonymous and nonymous, which is that this doesn't—


00:59:23<br>
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01:00:35<br>
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'''Brian Keating:''' I can do better as well. But I do want to say that this is maybe a general comment, not for pseudonymous and anonymous people, bananymous. But this is a general complaint that I've heard: it has to reproduce quantum theory. And I think, forget about that with regard to GU, it could be said about other theories, loop quantum gravity, etc. First of all, I think GU does produce what we would say is a relativistic quantum field theory in the Dirac equation, which is manifestly resplendent and produced and predicted. So I don't want to hear from you just yet, Eric, I do want to get your response. But this notion that a theory of everything has to subsume anything—I said this to our mutual friend, Stephon Alexander, professor at Brown University and esteemed cosmologist, and close friend to both Eric and myself, I said, "Look, I don't think it's valid to say that any theory of everything, String Theory or whatever, has to predict every manifestation of physics," and this is where I take issue, and I make truck with Professor Kaku, who says things like, "The one-inch-long God equation will predict everything." I don't think that's possible, (A) I don't think it's useful to think about the goal of physics is to predict every phenomenon in physics.
'''Brian Keating:''' I can do better as well. But I do want to say that this is maybe a general comment, not for pseudonymous and anonymous people, bananymous. But this is a general complaint that I've heard: it has to reproduce quantum theory. And I think, forget about that with regard to GU, it could be said about other theories, loop quantum gravity, etc. First of all, I think GU does produce what we would say is a relativistic quantum field theory in the Dirac equation, which is manifestly resplendent and produced and predicted. So I don't want to hear from you just yet, Eric, I do want to get your response. But this notion that a theory of everything has to subsume anything—I said this to our mutual friend, Stephon Alexander, professor at Brown University and esteemed cosmologist, and close friend to both Eric and myself, I said, "Look, I don't think it's valid to say that any theory of everything, string theory or whatever, has to predict every manifestation of physics," and this is where I take issue, and I make truck with Professor Kaku, who says things like, "The one-inch-long God equation will predict everything." I don't think that's possible, (A) I don't think it's useful to think about the goal of physics is to predict every phenomenon in physics.


01:01:54<br>
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01:04:20<br>
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'''Brian Keating:''' Now, when I look at the corresponding, shall we say, implications against String Theory, I would say things like the swamp land, the multiverse problem, these may be issues that cause stillbirth in many people's minds. I've talked to you about Paul Steinhardt, the Einstein Professor of Natural Science at Princeton—he regards the String Theory as essentially bad for society, not just for physics, not just for science, but bad for society because of the extravagance in a truest sense of the word, in a bad sense of the word, of the multiverse and string landscape. Now I know you're shaking your head—go ahead.
'''Brian Keating:''' Now, when I look at the corresponding, shall we say, implications against string theory, I would say things like the swamp land, the multiverse problem, these may be issues that cause stillbirth in many people's minds. I've talked to you about Paul Steinhardt, the Einstein Professor of Natural Science at Princeton—he regards the string theory as essentially bad for society, not just for physics, not just for science, but bad for society because of the extravagance in a truest sense of the word, in a bad sense of the word, of the multiverse and string landscape. Now I know you're shaking your head—go ahead.


01:04:58<br>
01:04:58<br>
'''Eric Weinstein:''' No no no. Let me be very clear about it. We're wimping out from what needs to be said, and it's really important the community gets it right. I don't think String Theory is a problem. String Theory can't harm anyone, String Theory doesn't—it's the string theorists when they're in their triumphalist mode, that it's an insufferable state of being. But even then, you know, I'm sure Feynman was insufferable, and I think Murray Gell-Mann was insufferable, and Pauli was pretty insufferable. We've had insufferable members of our community for a very long time, and we should not be getting rid of insufferable people. The problem is, what happens when people become insufferable and they don't constantly check in with the unforgiving nature of the universe. I mean, Pauli predicted the neutrino in an insufferable fashion.
'''Eric Weinstein:''' No no no. Let me be very clear about it. We're wimping out from what needs to be said, and it's really important the community gets it right. I don't think string theory is a problem. string theory can't harm anyone, string theory doesn't—it's the string theorists when they're in their triumphalist mode, that it's an insufferable state of being. But even then, you know, I'm sure Feynman was insufferable, and I think Murray Gell-Mann was insufferable, and Pauli was pretty insufferable. We've had insufferable members of our community for a very long time, and we should not be getting rid of insufferable people. The problem is, what happens when people become insufferable and they don't constantly check in with the unforgiving nature of the universe. I mean, Pauli predicted the neutrino in an insufferable fashion.


01:05:58<br>
01:05:58<br>
'''Brian Keating:''' And apologized. He apologized profusely, "I've done something which should never be done." Now, I asked you though, should String Theory—let's just be neutral to GU for a second. Should String Theory, from String Theory, emerge the Aharonov–Bohm effect? I mean, a true theory of everything, it would, right?
'''Brian Keating:''' And apologized. He apologized profusely, "I've done something which should never be done." Now, I asked you though, should string theory—let's just be neutral to GU for a second. Should string theory, from string theory, emerge the Aharonov–Bohm effect? I mean, a true theory of everything, it would, right?


01:06:19<br>
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01:07:00<br>
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Look, I want to defend both the string theorists and String Theory. These are incredibly smart people who found some real structure, and who never knew when to quit when it came to trumpeting just how much better String Theory is than everything else. Even there, they had a point. They were smarter and deeper, in general, than everyone else. They just weren't as good as they claimed to be, and they weren't as successful as they claimed to be, and what they did succeed that they didn't want to take credit for, because it was really mathematics done in physics departments rather than physics.  
Look, I want to defend both the string theorists and string theory. These are incredibly smart people who found some real structure, and who never knew when to quit when it came to trumpeting just how much better string theory is than everything else. Even there, they had a point. They were smarter and deeper, in general, than everyone else. They just weren't as good as they claimed to be, and they weren't as successful as they claimed to be, and what they did succeed that they didn't want to take credit for, because it was really mathematics done in physics departments rather than physics.  


01:07:34<br>
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01:12:06<br>
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'''Eric Weinstein:''' So we've got a metric. The metric has a connection, the connection produces curvature that's Riemannian. We find that by identities, it's got three components. It tries to go towards metrics and the Weyl curvature is snapped off. Afterwards, the scalar curvature is lowered somewhat, or adjusted, by scalar curvature over 2 times \(g_{\mu \nu}\). And so symbolically, what we've done is we've said Einstein threw away the Weyl curvature, readjusted the Ricci scalar curvature, and fed metric information through to the Levi-Civita connection, through to the Riemann curvature tensor, and then played these projection games to feed it back to the space of metrics. And that particular combination is perpendicular to the action of the diffeomorphism group on the space of all metrics, leading to a divergence free condition via our friend the Bianchi identity.  
'''Eric Weinstein:''' So we've got a metric. The metric has a connection, the connection produces curvature that's Riemannian. We find that by identities, it's got three components. It tries to go towards metrics and the Weyl curvature is snapped off. Afterwards, the scalar curvature is lowered somewhat, or adjusted, by scalar curvature over 2 times <math>g_{\mu \nu}</math>. And so symbolically, what we've done is we've said Einstein threw away the Weyl curvature, readjusted the Ricci scalar curvature, and fed metric information through to the Levi-Civita connection, through to the Riemann curvature tensor, and then played these projection games to feed it back to the space of metrics. And that particular combination is perpendicular to the action of the diffeomorphism group on the space of all metrics, leading to a divergence free condition via our friend the Bianchi identity.  


01:13:03<br>
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01:13:57<br>
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The problem here is the gauge transformations act on the Lie algebra component and don't touch the form component. But Einsteinian projection, or contraction, or summing over \(g_{\mu \nu}\) indices, is democratic: it deals simultaneously with the form piece and the Lie algebra piece. So if you treat only the Lie algebra piece under a gauge transformation and you don't touch the form piece, then contraction followed by gauge transformation will never be the same thing as gauge transformation followed by contraction. And so that's the puzzle, which is if Geometric Unity is really about the idea of trying to say maybe it's not so much quantizing gravity, maybe it's a fight between the different geometry of Riemann and Ehresmann, because gauge transformations are Ehresmannian geometry but contractions are Riemannian geometry.  
The problem here is the gauge transformations act on the Lie algebra component and don't touch the form component. But Einsteinian projection, or contraction, or summing over <math>g_{\mu \nu}</math> indices, is democratic: it deals simultaneously with the form piece and the Lie algebra piece. So if you treat only the Lie algebra piece under a gauge transformation and you don't touch the form piece, then contraction followed by gauge transformation will never be the same thing as gauge transformation followed by contraction. And so that's the puzzle, which is if Geometric Unity is really about the idea of trying to say maybe it's not so much quantizing gravity, maybe it's a fight between the different geometry of Riemann and Ehresmann, because gauge transformations are Ehresmannian geometry but contractions are Riemannian geometry.  


01:14:57<br>
01:14:57<br>
So here's a GU approach, how do you get geometric harmony between General Relativity and gauge theory when you have the ship in a bottle problem? This is almost a tight analogy. You've got the curvature tensor, you apply a gauge transformation to two of the masts and you pass them through into ad-valued \((d-1)\)-forms, and then you do an inverse gauge transformation, which is exactly how you do the ship in the bottle trick—by the way, Brian gave me a wonderful ship in a bottle, thank you very much—raising the mast inside. And then you can potentially, if need be, adjust one of the two masts again in order to get agreement.  
So here's a GU approach, how do you get geometric harmony between General Relativity and gauge theory when you have the ship in a bottle problem? This is almost a tight analogy. You've got the curvature tensor, you apply a gauge transformation to two of the masts and you pass them through into ad-valued <math>(d-1)</math>-forms, and then you do an inverse gauge transformation, which is exactly how you do the ship in the bottle trick—by the way, Brian gave me a wonderful ship in a bottle, thank you very much—raising the mast inside. And then you can potentially, if need be, adjust one of the two masts again in order to get agreement.  


01:15:40<br>
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01:28:33<br>
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'''Eric Weinstein:''' Alright. Imagine that that torus that you see in the lower left corner of the screen is a 2-dimensional model, toy model, of spacetime. So going around through the center is like Groundhog Day, you come back to the same place and it's a repeating time cycle, and space is simply a circle. Now in such a world, we would normally think of quantum field theory or gravity as taking place on that object. You'd have fields, you'd have effectively functions called sections on that object, and what you're seeing here is something that's very hard to picture because it's 5-dimensional, but one trick here is because the torus has a property called parallelizability... The object on the right is a depiction of a metric. Each point that isn't on one of those two sheets is a potential metric at any given point on the torus. So in other words, if a metric is a symmetric non-degenerate 2-tensor, if you think of it as a matrix, it would be of the form \(\begin{bmatrix} x & z \\ z & y \\ \end{bmatrix}\). Non-degenerate means that \(xy - z^2 \ne 0\). So that's what's cutting out that variety, if you will, the zeros of the of the determinant would be points, given that there are 3 degrees of freedom in the metric.
'''Eric Weinstein:''' Alright. Imagine that that torus that you see in the lower left corner of the screen is a 2-dimensional model, toy model, of spacetime. So going around through the center is like Groundhog Day, you come back to the same place and it's a repeating time cycle, and space is simply a circle. Now in such a world, we would normally think of quantum field theory or gravity as taking place on that object. You'd have fields, you'd have effectively functions called sections on that object, and what you're seeing here is something that's very hard to picture because it's 5-dimensional, but one trick here is because the torus has a property called parallelizability... The object on the right is a depiction of a metric. Each point that isn't on one of those two sheets is a potential metric at any given point on the torus. So in other words, if a metric is a symmetric non-degenerate 2-tensor, if you think of it as a matrix, it would be of the form <math>\begin{bmatrix} x & z \\ z & y \\ \end{bmatrix}</math>. Non-degenerate means that <math>xy - z^2 \ne 0</math>. So that's what's cutting out that variety, if you will, the zeros of the of the determinant would be points, given that there are 3 degrees of freedom in the metric.


01:30:21<br>
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01:31:36<br>
01:31:36<br>
So every point in that region is in play, and if you mapped—imagine that the stuff in that weird hourglassy region on the far right was like very warm and on the far left was very cold. Then if you map the torus in to the far left region, it would show up as being cold. If you mapped it into the far right region, you'd see it as being very hot. So every way of mapping the torus in pulls back different information from that hourglassy region. That is in large measure, in part, one of the things that may be going on with the illusion of many worlds, is that what you're seeing is that the metric may be capable of pulling back data that is dancing on the space of all metrics as well as the space of all points on the original manifold \(X\). So in this case, you've got 2 degrees of freedom on the torus, you've got 3 degrees of freedom around the hourglass, and \(2 + 3 = 5\).  
So every point in that region is in play, and if you mapped—imagine that the stuff in that weird hourglassy region on the far right was like very warm and on the far left was very cold. Then if you map the torus in to the far left region, it would show up as being cold. If you mapped it into the far right region, you'd see it as being very hot. So every way of mapping the torus in pulls back different information from that hourglassy region. That is in large measure, in part, one of the things that may be going on with the illusion of many worlds, is that what you're seeing is that the metric may be capable of pulling back data that is dancing on the space of all metrics as well as the space of all points on the original manifold <math>X</math>. So in this case, you've got 2 degrees of freedom on the torus, you've got 3 degrees of freedom around the hourglass, and <math>2 + 3 = 5</math>.  


01:32:38<br>
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01:33:15<br>
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So the big take home from the restrictive version of GU that we're exploring here is that if you allow fields to dance on the space of metric apparatus—measurement apparatus—then the paradoxes of measurement start to make a lot more sense. You could also, potentially, try to keep the metric classical, because we have two spaces. We have a space downstairs \(X\), which is just the torus, and we have a space upstairs, which is the torus, in this case, cross the hourglass region, as long as it doesn't touch the two sheets. So you've got a 5-dimensional manifold hovering over a 2-dimensional manifold, and fields on the 5-dimensional manifold will be perceived on the 2-dimensional manifold when you pull them back via a particular Einsteinian spacetime as fields on the tangent bundle of what you will call spacetime, together with fields on the normal bundle inside of the 5 dimensions.  
So the big take home from the restrictive version of GU that we're exploring here is that if you allow fields to dance on the space of metric apparatus—measurement apparatus—then the paradoxes of measurement start to make a lot more sense. You could also, potentially, try to keep the metric classical, because we have two spaces. We have a space downstairs <math>X</math>, which is just the torus, and we have a space upstairs, which is the torus, in this case, cross the hourglass region, as long as it doesn't touch the two sheets. So you've got a 5-dimensional manifold hovering over a 2-dimensional manifold, and fields on the 5-dimensional manifold will be perceived on the 2-dimensional manifold when you pull them back via a particular Einsteinian spacetime as fields on the tangent bundle of what you will call spacetime, together with fields on the normal bundle inside of the 5 dimensions.  


01:34:18<br>
01:34:18<br>
The normal bundle of a 2-dimensional manifold in a 5-dimensional space is 3-dimensional, so you're gonna see fields that look like spinors on 2 dimensions tensor spinors on 3 dimensions. If you were in 4 dimensions, make that torus in your mind represent a 4-dimensional spacetime, then that Diablo region would be a 10-dimensional region of metrics, because 4x4 matrices that are symmetric have \(\frac{4^2 + 4}{2}\) [Inaudible] for different degrees of freedom. In other words, you get a 10-dimensional normal bundle.  
The normal bundle of a 2-dimensional manifold in a 5-dimensional space is 3-dimensional, so you're gonna see fields that look like spinors on 2 dimensions tensor spinors on 3 dimensions. If you were in 4 dimensions, make that torus in your mind represent a 4-dimensional spacetime, then that Diablo region would be a 10-dimensional region of metrics, because 4x4 matrices that are symmetric have <math>\frac{4^2 + 4}{2}</math> [Inaudible] for different degrees of freedom. In other words, you get a 10-dimensional normal bundle.  


01:34:57<br>
01:34:57<br>
Now you'll notice that if you have ordinary spinors on 14-dimensional space and you pull them back via a metric, which is a mapping of 4 into 14, it looks like spinors on the 4-dimensional space tensor spinors on the 10-dimensional normal bundle. If the normal bundle inherits the Frobenius metric from \(X(1,3)\), and you glue in the trace piece in the right way—well, if you glue it in the wrong way, you'd get a \((7,3)\) metric on the normal bundle. But if you glue it in the right way, you'd get a \((6,4)\) metric on the normal bundle.  
Now you'll notice that if you have ordinary spinors on 14-dimensional space and you pull them back via a metric, which is a mapping of 4 into 14, it looks like spinors on the 4-dimensional space tensor spinors on the 10-dimensional normal bundle. If the normal bundle inherits the Frobenius metric from <math>X(1,3)</math>, and you glue in the trace piece in the right way—well, if you glue it in the wrong way, you'd get a <math>(7,3)</math> metric on the normal bundle. But if you glue it in the right way, you'd get a <math>(6,4)</math> metric on the normal bundle.  


01:35:35<br>
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\(\text{Spin}(6,4)\) is a sort of nasty non-compact group, so you might want to break to its maximal compact subgroup like Witten and Bar-Natan discuss. And the interesting thing about \(\text{Spin}(6,4)\) is that it has different names. By low-dimensional isomorphisms, \(\text{Spin}(6)\) is the same thing as \(\text{SU}(4)\). \(\text{Spin}(4)\) is the same thing as \(\text{SU}(2) \times \text{SU}(2)\). And \(\text{SU}(4) \times \text{SU}(2) \times \text{SU}(2)\) is the Pati–Salam theory. So you can argue that ordinary spinors on the induced metric in 14 dimensions, glued in the right way, pull back as Pati–Salam. And I don't know if anyone's ever discussed the connection between Einstein and Pati and Salam.  
<math>\text{Spin}(6,4)</math> is a sort of nasty non-compact group, so you might want to break to its maximal compact subgroup like Witten and Bar-Natan discuss. And the interesting thing about <math>\text{Spin}(6,4)</math> is that it has different names. By low-dimensional isomorphisms, <math>\text{Spin}(6)</math> is the same thing as <math>\text{SU}(4)</math>. <math>\text{Spin}(4)</math> is the same thing as <math>\text{SU}(2) \times \text{SU}(2)</math>. And <math>\text{SU}(4) \times \text{SU}(2) \times \text{SU}(2)</math> is the Pati–Salam theory. So you can argue that ordinary spinors on the induced metric in 14 dimensions, glued in the right way, pull back as Pati–Salam. And I don't know if anyone's ever discussed the connection between Einstein and Pati and Salam.  


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01:36:51<br>
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'''Eric Weinstein:''' And whether you're talking about \(\text{Spin}(10)\) models, \(\text{SU}(5)\) models, or \(\text{SU}(4) \times \text{SU}(2) \times \text{SU}(2)\), which is \(\text{Spin}(6) \times \text{Spin}(4)\), isn't that exactly what we see in the Standard Model? So Frank Wilczek—let me just see if I can find this beautiful quote from him, because he definitely brought this up. And what I recently did when I had him on my podcast, which we haven't released—so, if we go over to my screen share...
'''Eric Weinstein:''' And whether you're talking about <math>\text{Spin}(10)</math> models, <math>\text{SU}(5)</math> models, or <math>\text{SU}(4) \times \text{SU}(2) \times \text{SU}(2)</math>, which is <math>\text{Spin}(6) \times \text{Spin}(4)</math>, isn't that exactly what we see in the Standard Model? So Frank Wilczek—let me just see if I can find this beautiful quote from him, because he definitely brought this up. And what I recently did when I had him on my podcast, which we haven't released—so, if we go over to my screen share...


01:37:30<br>
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01:37:42<br>
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'''Eric Weinstein:''' Let me read it. "A particularly intriguing feature of \(\text{SO}(10)\)," which is really \(\text{Spin}(10)\)spin 10, or it could be \(\text{Spin}(6,4)\), "is its spinor representation, used to house the quarks and leptons, in which the states have a simple representation in terms of basis states labeled by a set of "+" and "-" signs. Perhaps this suggests composite structure." Now here's the sentence that just floored me. "Alternatively, one could wonder whether the occurrence of spinors both in internal space and in space-time is more than a coincidence." And then he pulls back immediately, "These are just intriguing facts; they are not presently incorporated in any compelling theoretical framework as far as I know." Geometric Unity is that compelling framework.
'''Eric Weinstein:''' Let me read it. "A particularly intriguing feature of <math>\text{SO}(10)</math>," which is really <math>\text{Spin}(10)</math>spin 10, or it could be <math>\text{Spin}(6,4)</math>, "is its spinor representation, used to house the quarks and leptons, in which the states have a simple representation in terms of basis states labeled by a set of "+" and "-" signs. Perhaps this suggests composite structure." Now here's the sentence that just floored me. "Alternatively, one could wonder whether the occurrence of spinors both in internal space and in space-time is more than a coincidence." And then he pulls back immediately, "These are just intriguing facts; they are not presently incorporated in any compelling theoretical framework as far as I know." Geometric Unity is that compelling framework.


01:38:26<br>
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01:45:45<br>
01:45:45<br>
'''Eric Weinstein:''' I think so, L'Shana Haba'ah in the electron layer.
'''Eric Weinstein:''' I think so, ''L'Shana Haba'ah'' in the electron layer.


01:45:49<br>
01:45:49<br>
'''Brian Keating:''' Okay, inshallah. Goodnight everybody. Please do subscribe and like this podcast, we have Michio Kaku coming up. John Mather, winner of the 2006 Nobel Prize—[Video cuts]—Magnificent ideas to the space, to make it safe for new ideas and for creativity, because we do have this one universe, this one life, and it is eminently precious. So for now, thanking you all, enjoy the rest of your evening, and thanking you Eric, here's a musical outro from our friend Miguel Tully, proprietor of the Yeti Tears podcast, Spotify, and YouTube channel. Good night, everybody.
'''Brian Keating:''' Okay, ''inshallah''. Goodnight everybody. Please do subscribe and like this podcast, we have Michio Kaku coming up. John Mather, winner of the 2006 Nobel Prize—[Video cuts]—Magnificent ideas to the space, to make it safe for new ideas and for creativity, because we do have this one universe, this one life, and it is eminently precious. So for now, thanking you all, enjoy the rest of your evening, and thanking you Eric, here's a musical outro from our friend Miguel Tully, proprietor of the Yeti Tears podcast, Spotify, and YouTube channel. Good night, everybody.





Latest revision as of 17:10, 19 February 2023

Eric Weinstein: A Conversation
KeatingWeinsteinConversation Cover Image.jpg
Information
Host(s) Brian Keating
Guest(s) Eric Weinstein
Length 01:46:34
Release Date 1 April 2021
Links
YouTube Watch
Portal Blog Read
All Appearances

Eric Weinstein: A Conversation was a livestream of Into the Impossible hosted by Brian Keating, dicussing Geometric Unity with guest Eric Weinstein.

Description[edit]

#GeometricUnity​ #EricWeinstein​ #ThePortal​ Eric Weinstein, host of the Portal Podcast, reveals Geometric Unity, his provocative new Theory of Everything. First discussed in 2013, later explored on the Joe Rogan Experience and Lex Fridman’s podcast, I am delighted Eric revealed the published version FIRST on The INTO THE IMPOSSIBLE Podcast.

See this Collection of Videos in Support of Geometric Unity https://pullthatupjamie.com
Watch Weinstein’s “April Fool’s” 2020 episode of The Portal, where he explains his theory of Geometric Unity: https://youtu.be/Z7rd04KzLcg​

Watch Weinstein’s latest interview on The Joe Rogan Experience.

https://youtu.be/wf0_nMaQ6tA

Transcript[edit]

The Portal Group's Transcript Completion Project generates and edits transcripts for content related to Eric Weinstein and The Portal Podcast. Completed transcripts are available to read on The Portal Blog and The Portal Wiki. If you would like to contribute, you can make direct edits to the wiki, or you can contact Aardvark or Brooke on The Portal Group Discord Server.

This transcript was generated with Otter.ai by Aardvark#5610 from this content's YouTube version. It was edited by Aardvark#5610. Further corrections and contributions were provided by pyrope#5830.

Introduction[edit]

00:00:15
Brian Keating: [Inaudible] And we are pleased to bring you a longtime friend of the campus, a friend of this cosmologist, a friend of physics, and that is none other than Dr. Eric Weinstein, who today is joining us from an undisclosed location, but maybe we'll get into that. We have already 114 people watching with many thumbs up. One thumbs down from my mother, Mom, how could you do that? That's wrong, Mom. Don't do that. It's just to me she said, not to you. Eric, how are you doing today?

00:00:51
Eric Weinstein: I'm well Brian, good to be with you.

00:00:52
Brian Keating: It's great to be with you. It's been four months exactly, or three months exactly, since we last conversed via this medium when we had on our mutual friends Max Tegmark and Garrett Lisi. And that was of course very enjoyable for me, to go over this, go over some of the long standing questions I've been having in this exploration of the multiverse of brilliant minds that grace me with their presence on the Into the Impossible podcast.

00:01:22
I have been not a stranger to the work that you've been working on. Some say it is the work of a lifetime. Some say it is revolutionary, and could have tremendous implications. Some have questions about it, because of its far reaching implications. And we're talking about universal theories of everything, perhaps a new one created by today's guest, Eric Weinstein. And that goes by the moniker Geometric Unity (GU), and I've been fascinated with this ever since I heard about it probably ten years ago, almost ten years ago now. And today, I thought it would be fun to get Eric on the show, as he has promised to at least be interested in coming on to discuss recent developments that the listenership of this fine podcast would be interested to know. And as you know Eric, we go deep.

Should a Theory of Physics Say Anything about God?[edit]

00:02:15
So first of all, I want to say thank you, and I want to ask you what is new in the theories of everything space? In particular, we're hearing a lot of talk nowadays from people like Michio Kaku, who will be a guest on my podcast next week, about "the God equation". And my first question to you, which is always of interest to me personally, is why does a theory of physics have anything to say about God, or any relevance to God whatsoever? Before we get into the nitty gritty details.

00:02:48
Eric Weinstein: Well, there are two things that I think that are up, which are—one is man's rigorous attempt to understand his circumstance necessarily intersects you with God, which is a traditional explanation for why is everything here, and the other is that God sells. Part of the problem is that if you name something "the really important particle that we just discovered", that's not going to sell as many books as "the God particle". And so we want to know God's thoughts, we want God particles, and then we back away from them. We claim, "No no no, I didn't mean God particle, I meant god damn particle." This is a game that we play with the public, where we try to amp the public up and get them hot and bothered, and once they're sufficiently in a lather, we try to educate them about the real nature of the universe. So think about it from a computer perspective as syntactic sugar. We're pouring God all over something hoping that people will swallow it.

00:03:49
Brian Keating: And of course, I'm holding up on the screen right now—on my screen I'm sharing a highlighted section from that great work of literature known as A Brief History of Time. This was one of the books that got me interested in cosmology and astronomy by the late great Stephen Hawking, who passed away exactly three years ago on Einstein's birthday, on Pi Day, at least here in the United States the 14th of March. By the way, do you know what other famous figure he shares his demise date with Eric?

00:04:21
Eric Weinstein: I don't.

00:04:22
Brian Keating: A Jewish intellectual by the name of Karl Marx. So Karl had an impact on universal capitalism, and Einstein, of course, was born that day, and Hawking died that day. And in the final paragraph of the book, he says if we can discover, if we can all have part in a final theory, "Then we shall all, philosophers, scientists, and just ordinary people, be able to take part in the discussion of the question of why is it that we and the universe exist. If we find the answer to that, it would be the ultimate triumph of human reason—for then we would know the mind of God." And, as you said, these things sell. It was rumored that he said every equation cuts your audience/readership in half, every mention of God doubles it. So at some level, there's conservation here, but I was always taught—

00:05:15
Eric Weinstein: [Inaudible]

00:05:18
Brian Keating: Sorry?

00:05:18
Eric Weinstein: Go ahead.

00:05:19
Brian Keating: I was always taught physics is not for "Why" questions, and yet there it is. He's bringing up "Why" questions. What do you make of that? Can physics provide the "Why"?

00:05:30
Eric Weinstein: I feel like, when you are talking in these terms, you are reasonably confident that the person is not trying to read the mind of God, because one wouldn't trifle with God in such a way. I believe that in some sense, if you're really worried that the telephone is connected, you'd probably speak about this differently. You might be humorous, you might—I don't know. There's something about the fact that we talk in this way, and it feels to me like when Moses is seeing a bush that is not consumed by flame but appears to be in flame, he knows pretty well that you should be a little careful. And I just, I don't understand the impulse to constantly God-ify everything.

Experiment and the Scientific Method[edit]

00:06:23
Brian Keating: And certainly, I'll have on Michio Kaku next week on the Into the Impossible podcast, and I hope maybe we'll get a cameo from you. But in his book, he writes something very provocative. And he says at the end of his book, he quotes those lines from Stephen Hawking, which is kind of like this infinite regress, which kind of strains credulity, so to speak. But he says, at one point he says, "It's not fair to test string theory, to ask to test string theory experimentally, because we don't know its final principles." But the same, I claim, could have been said about quantum mechanics. Do we know the final principles of quantum mechanics? Does that immunize it from experimental test?

00:07:10
Eric Weinstein: Again, these are the same questions over and over again. There's something very wrong about the simplistic nature of the scientific method, and the relationship between experiment and theory, and instance and idea. We're effectively playing through the exact same set of problems: where we hold up one theory to some sort of experimental threshold, we give a pass to another theory. We're all the time pretending that we're not actually doing what we're really doing, which is observing who believes in what theory.

00:07:42
One of the reasons string theory got such a boost is that the brilliance of the initial volunteers for the first string revolution around 1984 were so good that we were inclined to give them a huge pass, at least at first. And then, we have this differential application where the string theorists become paradoxically the most persnickety about what is a prediction, because they don't want to give up the fact that they aren't really making predictions. So if you, for example, predict internal quantum numbers of the next particles to be found, but you don't come up with an energy threshold, and you don't say what will invalidate your theory, they get angry. Because, in fact, what we've done is we've given them an asymmetric relationship with the scientific method through special pleading.

00:08:35
So we have a really unfortunate situation, which is that we have highly simplistic Popperians, highly simplistic devotees of the scientific method—and I really think that people need to go back to Dirac's 1963 Scientific American article to understand that the real issue is very weird, and we haven't really talked about it. There were three big names in the 20th century in my mind, who contributed something like physical law. And leaving Dr. Mills out of it for the moment, I would say that Einstein, Dirac, and Yang tower, not necessarily that they're the best physicists, although I think I could make a pretty good claim in all three cases, but that physical law is different than the consequences of physical law. And the people who seem to do well with physical law employ mechanisms that would drive Sabine Hossenfelder to distraction. They talk a lot about beauty, and elegance, and simplicity. And what Dirac said was don't force people who come up with new physical laws to play the game of agreement with experiment, because the instance of an idea can easily be off and not agree with experiment.

00:09:55
And then you have a problem whereby you're pushing people initially. The instant you open your mouth, "Say what it is that would invalidate your theory so we'll know that you're wrong if you're wrong." And I don't know who this is intended to fool. It's completely irresponsible. And what it is, is an attempt to constantly take anyone who would come forward with an idea and put them instantaneously on the defensive. I think that the right thing to do is to sit people down and say you're supposed to be adults. If we look at our history, everybody who has proposed new physical law and gotten it right had errors. Einstein didn't get the divergence free part. He was vague before that with Grossman. Famously, Dirac's theory of quantum electrodynamics took almost 20 years before the renormalization revolution supplied the ability to compute with it. We had a confusion between the bare and the dressed mass. And famously, the degeneracy between the electron and the proton: we had two particles that Dirac claimed to be anti-particles, because he was too timid to suggest a positron and an antiproton, which Heisenberg [inaudible] has the mass asymmetry. Yang's theory, if left massless, wouldn't come up with the right rates for beta decay if you didn't impart mass to the W and Z, to the intermediate vector bosons.

00:11:29
So I think that you have a situation by which new ideas are always not properly instantiated, and the community that is constantly trying to make sure that... I think that the idea is that people are foolish enough to play this game with the most aggressive members of the community, because the implication is if you won't come up with a testable prediction that invalidates your theory, you're anti scientific and we have no time for this. And so people, well like, you know, with the [math]\displaystyle{ \text{SU}(5) }[/math] theory, they immediately said okay, well it predicts proton decay. Well, grand unification is a larger idea, and some versions and instantiations do predict proton decay, and some do not. So what are you going to say about that? I think that the problem is that we're not in an adult phase where we've faced up to the fact that we have almost 50 years of stagnation, and what you're seeing with this proliferation of new claimants to have fundamental theories is, in part, that string theory has finally weakened itself, and the aging of the particular cohort—which is Baby Boomers, who are the string theory proponents—they've gotten weak enough that effectively other people feel emboldened. And I think Stephen Wolfram said this recently, that in a previous era, he would have expected to have been attacked. But we've been waiting around for so long that perhaps the political economy of unification and wild ideas has changed somewhat.

Approaches to a Theory of Everything[edit]

00:13:07
Brian Keating: And before we get off the subject of the "Why" questions, I do like a framework that I've heard you, and almost no one besides you, portray laws of fundamental physics, and that's using the good old fashioned mechanism we were all taught in high school journalism: the "Five W" approach. And I wonder if we could start there, with why that is a good deconstructivist approach to ascertaining the realm of validity of a physical law, of a purported new theory, a theory of everything—which I dislike that moniker as you know. But nevertheless, can you talk about that framework and how, for our up and coming but bright listeners, of which there are many currently watching right now, how you approach that using the "Five W's", why that's so important, and then maybe that will segue into a description of the actual physical instantiation of that framework.

00:14:07
Eric Weinstein: I will point out that how has the "W" on the end. Yeah, I think that... I usually do it as "Where" and "When", "Who" and "What", "How" and "Why". And let's just say, first of all, what we generally speaking mean by a theory. What we're usually talking about is a way in which waves can propagate and interact in various media. All right? The theories of the world are theories of waves and interaction. Waves imply a medium. So the "Where and When" is sort of a particular kind of a substrate, usually, which Einstein imbued with the name spacetime, "Where" being space, "When" being time. The "Who" and the "What" I take to be fractional spin and integral spin particles; every particle that we know of that's fundamental is one or the other. So, let's say that the "What" is the fermionic, fractional spin particles, and the "Who" is the integral spin, generally speaking force particles, non-gravitational—but then we also have to throw in the Higgs and the metric for spin-0 and spin-2. And then there's the "How" and the "Why", the "How" would be the equations of motion, and the "Why" would be the Lagrangian that generates the equations of motion.

00:16:03
And so, in some sense, it's not surprising then that the theory has to conform to the basic idea of when you're trying to tell somebody something, these are the questions that we want to ask, and it's a surprisingly tight mapping. And I just find that people can better remember that, because very often what we've done is we've taught people to focus on the wrong things when we talk about fundamental physics. They're overly focused on entanglement. They're very focused on quantum measurement. They have no idea about bundles, they don't have ideas about symmetry groups or why symmetry groups are important. And so, for some reason, when people learn about theories of everything, they're very animated, but they're very animated as to on the grounds of what has sold books recently.

Limits and Methods for Constructing the Universe[edit]

00:16:54
Brian Keating: That's right. And we have no shortage of multiverses, double-slit experiments, spooky action at a distance, and other invocations of this gentleman [Albert Einstein]. I point out that Einstein is Weinstein with[out] a W. Okay, you have a fascination with W's, obviously. So, I want to go starting with Einstein, to something that I know is very influential to you. And it's sort of a provocative question that has inspired you, apparently. And that was a question, a stylized question, posed to Ernst Strauss by Albert Einstein, regarding the amount of freedom present in our field theoretic universe. What is that question?

00:17:43
Eric Weinstein: Well, the question is how much freedom is there in what we take to be the Standard Model—and I'm sorry, I'm using a term of art accidentally. How much freedom is there to construct the universe? And is this one of many that could have been constructed, or is it effectively unique? And are we talking about the God concept, if you will, as a design constraint, where things are the way they are because they could not be otherwise? And I think that it's a very interesting question, because in some sense, I don't know that he meant it this way, but I took it to be a research program.

00:18:35
Brian Keating: And in terms of it providing this direction for you, is the question itself the research direction? Or is the overarching theme, of sort of freedom, flexibility within physical laws, the programmatic kind of marching orders that you took unto yourself?

00:18:55
Eric Weinstein: It's an interesting question. I mean, I think that what I don't understand is that people talk about theories of everything casually, as if a theory of everything is sort of—it may not be a very artful term. It's sort of theories of all the rules, not what can be played with once one knows all the rules. I guess what I take it to mean is that we have a problem of even conceiving of what a non-effective theory would be. Well, what is an ultimate theory? I mean, I think that in large measure I see two kind of canonical versions. One of them I would sort of associate with Garrett Lisi's E8 idea, although I don't believe that that works. You start with something incredibly rich that exists by necessity, like a large exceptional Lie group, or maybe a large finite group, or something that is somehow distinguished. And then you attempt to milk it for peculiarities that can be identified with our world, and that's how you get the richness of our world. Whether or not you believe in Garrett's theory, I do think it's emblematic of an approach.

00:20:08
Another approach is closer to embryology, where you start with something that is deceptively simple, like a single fertilized egg. Then you ask, does that attempt, in some sense, to bootstrap itself into the totality of existence? And that's much closer to what I ended up doing. I mean, I considered Garrett's E8 thing before I ever met Garrett, because E8 is spinorial, it's chiral, it has lots of stylized things that seem to fit our world, but I couldn't figure out how to really make it into a theory, and then I went the other direction. I think it's pointless to ask why is there something rather than nothing, unless I'm mistaken. I think that the point of a fundamental theory is to get the scientists to accept the initial input is so uninteresting to go beyond that they put down their pens, and the theologians and philosophers take over.

00:21:08
If you imagine that the initial input to the universe is just 4 dimensions, for example, I don't think that many scientists would be motivated to say "Why are there 4 dimensions?" at a scientific level, because that sort of begs the—it's not enough of a clue for anything to proceed scientifically. I mean, maybe all versions have multiple dimensions, maybe there's 17 dimensions too. So I think that in large measure, the gambit that I'm trying to follow, as misguided as it sounds, is, "Is four dimensions on its own, in the form of a manifold with a few extra mild conditions," like a single unique spin structure, something like that... Orientable. "Is a nice 4-dimensional manifold sufficient to start the universe from effectively no other major assumptions?" And that's how crazy this is.

00:22:17
Brian Keating: So when you say "this", we're talking about Geometric Unity. A reminder, we're talking to Eric Weinstein, Dr. Eric Weinstein, proprietor of The Portal Podcast. And you can find his YouTube channel at nobani88, which is a cryptic reference to the year I had my first kiss. I don't know why it's called that, but it should be The Portal, we'll get that fixed. Eric, if in the meantime, could you tilt your webcam down just a tiny bit, so your head is not at the bottom of the of the frame? That would make it—Yes, very good. Very nice.

What is Fundamental?[edit]

00:22:47
So, what is fundamental? I've had these conversations just recently on my podcast with Dr. Stephen Meyer, who you know is a proponent of the intelligent design hypothesis, I'm not going to get into that. I am a critic of that, and then we are yet good friends. But he makes the case that in things like the Guth Vilenkin conjecture, or in the Lawrence Krauss universe from nothing, we always start with the laws of nature and instantiation thereof. So too with debates I've had with Sean Carroll, a friend of mine, and a greatly respected mentor in the field. That God could have chosen to start the universe with an empty Hilbert space is his conjecture, and therefore, there's a simpler universe than the one we inhabit. We're not going to talk about Sean necessarily, we're not going to talk about Stephen Meyer. But I want to talk about what is the fundamental element, the yealm, the thing from which emerges spacetime? Or is the spacetime, or observerse if we can go there now, is that truly fundamental, or is it emergent? What comes first, the observerse or the observer?

00:23:59
Eric Weinstein: Well first of all, I mean, let me just say a few words. What we're talking about is crazy. And I think it's really important to just own up to the fact that for people who want sober physics, this is probably not the channel for you today. Now... No, I mean, I take this stuff very seriously because I don't like the bullshitty aspect. And we're using April 1st as a contrivance, because I think that many people are induced to self-inhibit, because particular members of the community are incredibly aggressive in making it extremely expensive to explore ideas. And I'd like to think that living outside the community, I could start a tradition to make it at least inexpensive one day a year to throw the middle finger to those people who like to play Simon Says games, or reputational destruction games. Now—

00:25:01
Brian Keating: A purge. A purge for physics.

00:25:05
Eric Weinstein: Well, there should be many more such days, and I'd love to get there. But let's at least start with one a year. So, this is my second year round trying to hit this. Look, I believe, that at some level, that the initial ingredient may just be a 4-dimensional manifold. And then things emerge from that. A 4-dimensional manifold with a little bit of extra structure—but that's why this is crazy.

00:25:37
Brian Keating: So it starts from very modest inputs, and from such modest inputs comes a rather extravagant universe. Let's talk about the inputs. I don't know how closely you want to follow, if you want to share screens or anything like that, we're free to do that. What are the inputs? There are the players, the matter players, there are the gauge bosons, there are new predictions, there are new concepts that Geometric Unity has provided. And so the question, I guess first of all, is how close do we want to follow this prescription of what has been portrayed in the past? And/or do we want to talk about what is new in the preceding year since the last episode of April Fool's purge podcasting began with The Portal special episode?

00:26:34
Eric Weinstein: Well, it's very interesting to consider that we've had a year where there's been a fair amount of interest in it. And, let's be honest, very little of the interest has been particularly detailed. I would have thought that maybe what I said was ununderstandable. And then, oddly, a paper purporting to critique the theory managed to demonstrate that they had understood fairly well what I had said, and that it was understandable. Unfortunately, there was one named author and a [sic] imaginary friend, and I don't respond well to people posing behind pseudonyms. But part of that was constructive. And, you know—I'm attempting to share a bit of screen now.

00:27:45
Brian Keating: Okay. Here, I'll add that. Okay. So now it's full, you've got the full screen on the paper.

Forgotten Problems in Physics[edit]

00:27:59
Eric Weinstein: So effectively, what I'm asking is, can a manifold [math]\displaystyle{ X^4 }[/math] produce the baroque structure of the Standard Model? Now—and gravity. And if you think back to the famous mug popular in the CERN gift shop, there really isn't that much going on in the Standard Model if you group terms in particular ways. But there's a lot of weirdness. Why the Lorentz group, why [math]\displaystyle{ \text{SU}(3) \times \text{SU}(2) \times \text{U}(1) }[/math] for the internal symmetries generating the forces, why three families? I thought that something that many younger viewers may not be aware of is that things really changed around 1983, '84. If you think about the original anomaly cancellation of Green and Schwarz in 1984, I believe, you could ask what was physics like right before that moment? And I think it's absolutely shocking, because we don't realize the extent to which the string theorists really redefined what the major problems in physics were. I think most people in the post-string era somehow believe that the major issue is quantum gravity. And I don't really, I just find it astounding, because that's really what the string theorists were selling.

00:29:34
So this is from Murray Gell-Mann's address to the second Shelter Island conference, where they're trying to recapture the magic from Ram's Head Inn after World War II, when the young physicists were invited to—feeling that they had done well on the engineering project that was the Manhattan Project, they were buoyed in their confidence. And years later in 1983, Murray Gell-Mann says well, what are the big problems? "As usual, solving the problems of one era has shown up the critical questions for the next. The first ones that come to mind looking at the standard theory of today are," and then, I think this is absolutely shocking and indicates the extent to which the current generation has really given up on doing what we would typically have called physics, relegating the things that are relevant to the physical universe that we see usually to the realm of particle phenomenology.

00:30:32
Okay, so what are his big questions? Why this particular structure for the families? In particular, why flavor chiral with left- and right-handed particles being treated differently by the weak force, rather than say vectorlike ones left and right transformable into being treated the same? Next, why three families? That generalizes Robbie's famous question "Who ordered that?" as if the universe was a Jewish deli, commenting on the muon. How many sets of Higgs bosons are there? We talk about the Higgs boson, but maybe there are multiple sets and there are multiple different scales at which symmetry is broken and mass is imparted through soft mass mechanisms. Lastly, why [math]\displaystyle{ \text{SU}(3) \times \text{SU}(2) \times \text{U}(1) }[/math]? Remember, [math]\displaystyle{ \text{SU}(3) }[/math] is the color force for the strong force, but [math]\displaystyle{ \text{SU}(2) }[/math] here is weak isospin, which has not yet become the W and Z's. And this [math]\displaystyle{ \text{U}(1) }[/math] is weak hypercharge, which has not yet become electromagnetism through symmetry breaking. And in some sense, I just feel sort of sad that we don't think of these as questions because we know not to ask them.

00:31:42
And somehow we got convinced that we were being called to quantize gravity, not necessarily—if gravity is geometric, you could just as easily have said should we be geometrizing the quantum? And if we geometrize the quantum, you would notice that this era would have been triumphant, because that's really what happened. We didn't do a lot of physics, but we really did put the framework of physics—that is quantum field theory, quantum measurement, classical field theory—all in very geometric frameworks. In fact, I would say that there were three really big revolutions, although we don't talk in these terms. One was the discovery by Simons and Yang of the Wu–Yang dictionary, I'm blanking on Wu's name, which Is Singer was also instrumental in taking to Oxford. Then there's the geometric quantization revolution, where the quantum was understood to be intrinsically geometric because the Heisenberg uncertainty relations should emerge from the curvature tensor of a prequantum line bundle, but the sections being the states of a vector space once polarization is taken into account. And then lastly, the geometric quantum field theory revolution, in which we came to understand the quantum field theory really isn't about the physical world, that it gets applied in one particular set of inputs to the physical world, but it's actually a mature mathematical enhancement of bordism theory from topology, strangely. So, those three major revolutions all went exactly counter to quantized gravity. They said, "Let's geometrize the quantum instead," and so they did.

00:33:26
Brian Keating: And did—how successful should we regard this? The resulting byproduct or lack thereof progress, lack thereof in the intervening...?

00:33:38
Eric Weinstein: This is very unpleasant to have to say this, but I think that we are talking about a great era with heroes. The top hero among them is undoubtedly Ed Witten. But I do believe that Yang and Simons, I think Yang and Simon's discovery of Ehresmannian bundle theory, which has a precursor—and I'm blanking on the gentleman's name (Robert Hermann), all the self published books from from the '60s. It'll come to me, but there was a man in Boston who probably got there a little bit earlier. And then I would say that you have accidental physicists. Dan Quillen, for example, did a huge amount to talk about connections on determinant bundles and the like, which come out of various quantization procedures, particularly with Berezin integration of fermion sectors. So I think that a lot of things got done to shore up what we do to mature input into a quantum theory. It just, it wasn't physics, per se. It was sort of the mathematics of physics. And I think that that was very frustrating, which is, you know, it's sort of, to physicists it's yeoman's work. They wanted to go to Stockholm, and they ended up winning the first Fields Medal won by a physicist, and I think—it's weird. It's like, what is your time? Your time is whatever it is that can be done. And they thought their time was to quantize gravity. "Well guess again," nature said, "we have something incredibly important." So I feel like I'm trying to rescue their legacy. They want to go down as string theorists for the most part. And they want to say that string theory was the most successful of any claimant, even though it wasn't very successful. And, my feeling is—

00:35:39
Brian Keating: Now, can you say it's not—Go ahead.

00:35:44
Eric Weinstein: Well, yes, I feel like we can say that it's not very successful, because they gave us the terms in which we should evaluate it. You know, I remember being told "Give us 10 years, we'll have the whole thing cleaned up. Don't worry your pretty little head, we'll be fine," or, "We have a finite number of theories to check." And then lo and behold, there's a continuum, or why is it called string theory when there are branes involved? And it was because if you asked once upon a time, they'd say, "Well, it's not like mathematicians think about higher-dimensional objects beyond strings." There was an explanation for why there were no branes. And, you know, that—yes, string theory has failed in its own terms. Now is it salvageable, are there pivots beyond? Yeah, sure. I'm not saying that they didn't stumble on a tremendous amount of structure, maybe that structure ultimately carries the day. But I do think that the idea that they're entitled to this many pivots without having to become self-reflective is preposterous. And I think many people feel that way, and they know that they might pay for such a statement with their career. And since I've prepaid, it falls to people like me and to you, perhaps, to say look, the string theorists weren't able to confront their failure.

The Grand Nature of Physics[edit]

00:37:11
Brian Keating: When we talk about these things in rather, some say, grandiose terms, I think sometimes we do lose sight.

00:37:19
Eric Weinstein: [Inaudible] I really don't want to use the word grandiose. Like, are we going to talk about grandiose unified theory? Let's be honest about it. Physics is the most honest way to ask the most grand questions in the universe.

00:37:36
Brian Keating: Absolutely.

00:37:36
Eric Weinstein: If physics is grandiose, then we've got real problems. Then grand doesn't exist. And if grand doesn't exist, then grandiose doesn't exist. So, my feeling is no. This is the actual grand quest, and we're not going to back off it and be pussies about it. This is not grandiose, this is the real deal.

00:37:54
Brian Keating: I was thinking, speaking of myself, being a self-aggrandizement of seeking these ultimate questions, but we do, and I was gonna give physics a good deal of credit, because we do ask these ultimate questions. And yet, of course, day to day basis, I remember wanting to help you out as little [a] role I could play in the exposition of this magnificent opus that you're working on, and saying, "Eric, this is great, but I got a bunch of kids that I gotta go pick up." And you said "Well, maybe that's why we'll never get off the planet, because guys and girls"—

00:38:28
Eric Weinstein: Everybody has to pick up their dry cleaning.

00:38:30
Brian Keating: Every time you gotta pick up your dry cleaning—but when we lose sight of it, I find with my colleagues, and I'll speak, because I doubt many of them are listening. I really don't feel like they're that curious, intellectually. I think it is a job. I think their their job is the dry cleaning. And I can sort of prove that in some ways, because I often hear them say things like well, Eric is a showman, he's a podcaster. He's a host, and he's had training, and he's very smooth, and he can speak well. And I say "Well, do you think he do you think he emerged from the womb like that? And by the way, Mister or Missus Professor, Doctor Professor, you have got a lot of training in quantum field theory and string theory yourself. That was presumably a challenge for you. You didn't emerge womb-like, you know, from the caverns of the womb, knowing quantum field theory, so you had to work at that." So it's all about prioritization. Why do you think physicists aren't more troubled by the lack of progress, that our mutual friend Sabine has pointed out, in the last 50 years, at least in fundamental physics? My colleagues will rightfully point out tremendous advances in cosmological theory, in condensed matter theory, etc. But why isn't that more troubling? I think the answer is we're not that curious. You have a vision of us that's maybe more more refined than I think we deserve, and that's because you're not a professional physicist.

00:39:54
Eric Weinstein: Look, I feel very similar about my feelings about physics as an outsider to the way I view the UK. When I go to the UK, very often they they seem to be defeated, because they lost their empire which they should never have had in the first place. But my feeling is if you really look at the UK, it's an amazing place, and any outsider should be able to see that. I guess what I think about here is that any outsider who really takes physics seriously should be able to see that this is our premier community, intellectually. It is the most accomplished of intellectual communities. And it's also very badly behaved, and it's fallen on hard times.

00:40:39
It's like seeing a grand family that's forgotten itself, because it has to constantly submit to the arXiv. We now have the snarXiv, as you know. The snarXiv is filled with papers that are indistinguishable as a Turing test from arXiv papers. I think I looked for like, I don't know, the Gell-Mann–Nishijima formula on hep-th, and I realized that people really weren't doing physics. You know, there's certain things that you would have to do if you were going to do physics. I don't mean to say that no physics is going on, but my God, it's really people that just don't believe anymore. I think that when you're talking about almost 50 years of a particular kind of failure in fundamental physics, where theories and predictions effectively become accepted as being the likely explanations for the universe. We're getting to the point where everybody who's contributed to the Standard Model after this year will be over 70.

Understanding Geometric Unity[edit]

00:41:44
Brian Keating: What do you say to the younger people who say they can't understand it, they can't comprehend Geometric Unity. Our friend Sabine, she can't understand it. Is it too complex for her?

00:41:57
Eric Weinstein: No, there's a bunch of different games. One game is the "I can't understand all this fancy pants stuff." Another game is "Be hyper specific so we can invalidate you." There's another game, which is, "Well, we know that you don't know quantum field theory really well, so what energy level do these things kick in at?" And I find all of this incredibly dispiriting and exhausting, because it's also transparent. We can say what Geometric Unity actually is. We can draw a picture and people can get it. And in fact, I was talking to my good buddy Joe Rogan earlier today, and a particular group of people that listen to my podcast put up a site for Joe called pullthatupjamie.com. If you want to navigate to pullthatupjamie.com—in part, this is below Sabine's level. But I'm happy to, you know, if you got her on the horn, she could understand what's being said.

00:43:09
Brian Keating: Yeah, I have no doubt about that. The question is, when we talk in the language of bundles, of fibers, etc, at what level do people kind of lose the physics for the geometry, for the pure mathematical? And I think—

00:43:26
Eric Weinstein: Let's walk the first step, and then let's watch people who are technically capable claim that they can't follow what's going on, because I don't think it's true.

00:43:35
Brian Keating: So...

00:43:38
Eric Weinstein: You have [math]\displaystyle{ X^n }[/math] for a manifold of n-dimensions. Make it orientable with a particular orientation, make it have a unique spin structure, whatever you need to do to set it up as a decent manifold. Replace that manifold, momentarily, by the bundle of all metric tensors pointwise on the same space. And that way, spacetime would be a particular section of that bundle. Let me see if I can find a...

00:44:19
So the first thing is that the observerse replaces spacetime. And, again, you're not trying to kill off Einstein, you're trying to recover Einstein from a different structure. So I'm looking...

00:44:43
Okay. So right here, I've got a 4-dimensional manifold. Imagine that I'm interested in looking at the bundle of all pointwise metrics, which is going to be—if the base space is 4-dimensional, make [math]\displaystyle{ 4 = n }[/math]—it will be of dimension [math]\displaystyle{ n^{\frac{n^2 + 3n}{2}} }[/math]. So [math]\displaystyle{ 4^2 }[/math] is 16, plus [math]\displaystyle{ 3n }[/math], [math]\displaystyle{ 3 \times 4 = 12 }[/math]. So [math]\displaystyle{ 16 + 12 = 28 }[/math], divided by 2 is 14. If you have a [math]\displaystyle{ (1,3) }[/math] metric downstairs, I believe that you are naturally courting a [math]\displaystyle{ (7, 7) }[/math] or [math]\displaystyle{ (9, 5) }[/math] metric upstairs. And that is the first step in GU, which is that you replace a single space with one particular metric by a pair of spaces, a total space and a base space of a fiber bundle—this is in the strong form of GU—and physics mostly happens upstairs on the bundle of all metrics, not downstairs on the particular space that got you started.

00:46:02
Here, [math]\displaystyle{ U^4 }[/math] is an open set in [math]\displaystyle{ X^4 }[/math]. Okay, so effectively, what are we saying? We're saying that physics is going to dance on not only the space of four coordinates, typically [math]\displaystyle{ x }[/math], [math]\displaystyle{ y }[/math], [math]\displaystyle{ z }[/math], and [math]\displaystyle{ t }[/math], or thinking in a coordinate-independent fashion, simply four parameters, it's also going to dance on the space of rulers and protractors at every given point. And so that structure is the beginning of GU, and then you can recover Einstein, spacetime, by simply saying that if I have a section of that bundle, that's a spacetime metric.

00:46:55
Brian Keating: So when you say in the simplest form, or in the reduced form of GU, what do you mean?

00:47:03
Eric Weinstein: Well, I gave three forms of GU. One form is the trivial form, in which you have the second space [math]\displaystyle{ Y }[/math] the same as the first space [math]\displaystyle{ X }[/math]. That means that you can easily recover everything Einstein did as a form of Geometric Unity by trivially making the observerse irrelevant. You're just repeating the same space twice, and you've got one map between them called the identity, and now you're back in your old world. So without loss of generality, you cover that. Another one is a completely general world, which I think—What did we call it here... Well, I called the middle one the Einsteinian one, where you actually make the second space [math]\displaystyle{ Y }[/math] the space of metrics. And that's the one that I think is the most interesting, but I don't want to box myself in, because I don't want to play these games of Simon's "You said this," or "You said that." You know, I can play the lawyerly game as well as anyone if that's what we are really trying to do. I thought we were trying to do physics.

00:48:19
The thing that I'm trying to get at here is that I believe you and I are somehow having a pullback of a 14-dimensional conversation right now. My guess is that there is a space, with a [math]\displaystyle{ (7, 7) }[/math] metric, probably more likely than a [math]\displaystyle{ (9, 5) }[/math] metric, on 14 dimensions, where not only are the waves that are relevant going over the original coordinates [math]\displaystyle{ x_1 }[/math] through [math]\displaystyle{ x_4 }[/math], they're also going through four ruler coordinates on the tangent bundle of the original [math]\displaystyle{ x }[/math] coordinates. So there are 4 rulers to measure the 4 directions, and then there are also going to be 6 protractors. Because if you name the directions John, Paul, George, and Ringo, you'd have John with Paul, John with George, John with Ringo, Paul with George, Paul with Ringo, George with Ringo. Right? And so, those 6 protractors are actually degrees of freedom for the fields, and the fields live on that space.

00:49:30
Then the question is why do we perceive 4 dimensions and complicated fields? And the answer is pullbacks. When you have a metric, you have a map from the base space into the total space, so Einstein—we don't think of it this way—is embedding a lifeless space which is without form, [math]\displaystyle{ X^4 }[/math], into a 14-dimensional space before Geometric Unity ever even got on the scene, and giving him the ability to pull back information, which he may say is only happening on that tiny little slice, that little filament that is the 4-dimensional manifold swimming in a 14-dimensional world with a 10-dimensional normal bundle. But why not imagine that actually the fields are actually spread out over all 14 dimensions, and then all you're seeing is pullback information downstairs. Now the metric is doing something new that it wasn't doing before. It's pulling back data that is natural to [math]\displaystyle{ Y^{14} }[/math] as if it was natural on X, but I call this invasive fields versus native fields, just because some species are invasive, and some species are endemic, or native. The interesting thing about the bundle of all spinors, sorry, the bundle of all metrics, is that it almost has a metric on it. I don't know if I've ever heard anyone mention this.

00:51:02
Brian Keating: The space—repeat that. The space of all metrics almost has a metric on it?

00:51:08
Eric Weinstein: Yeah, nearly.

00:51:09
Brian Keating: Explain?

00:51:09
Eric Weinstein: So in other words, assume that you haven't chosen a metric on [math]\displaystyle{ X^4 }[/math]. What you have then is you have a 10-dimensional subspace along the fibers, which we can call the vertical space. And that 10-dimensional space at every point upstairs, every point is, in fact, a metric downstairs, being by construction. So that means it imparts a metric on 10-dimensional vectors along the fibers. Now those are symmetric 2-tensors, effectively, because it's a space of metrics. You have this really interesting space here, call that [math]\displaystyle{ V }[/math]. Well that [math]\displaystyle{ V }[/math] has a Frobenius metric based on the particular metric at which you are looking at the tangent space, which has got a 10-dimensional subspace picked out. If you map that 10-dimensional subspace into the 14-dimensional tangent space of the manifold [math]\displaystyle{ Y^{14} }[/math], you can take a quotient and call that [math]\displaystyle{ H }[/math]. And that [math]\displaystyle{ H }[/math] will also have a metric because it's isomorphic to the dual of the pullback of the cotangent bundle downstairs. And the cotangent bundle has a metric because at that point that you picked in [math]\displaystyle{ Y^{14} }[/math] is itself a metric downstairs.

00:52:40
So now you've got a metric on [math]\displaystyle{ V }[/math], you've got a metric on [math]\displaystyle{ H^* }[/math], and you just don't know how [math]\displaystyle{ H^* }[/math] becomes the complement to [math]\displaystyle{ V }[/math] and [math]\displaystyle{ T }[/math]. That's the only piece of data you're missing for a metric. So you've got a 4-metric, you've got a 10-metric, the 10-metric is sitting inside of the tangent. The 4-metric is naturally sitting inside of the cotangent bundle. They're weirdly complementary, you've got a metric on the nose but for one piece of data, which we call a connection. So up to a connection, the manifold [math]\displaystyle{ Y^{14} }[/math] has a metric on it without ever having chosen a metric because it's made out of metric data.

00:53:21
Now spinors have a really interesting property, which I would call an exponential property. That is, the spinor of a direct sum is the tensor product of the spinors on the summands.

00:53:36
Brian Keating: That's not true for any spin, or is that true for any spin, or just half integer, or...?

00:53:43
Eric Weinstein: Well, that's true for any—no, it's true for the spin representation. It's not true generically, for any representation. But it allows you to build the spinors on what should be the total space, because now you've got a 4-dimensional... So, I think it's here at 3.12. If the spinors of a sum are the tensor products of the spinors on the summands, and I create a new bundle, which is the 10-dimensional vertical bundle inside the tangent bundle direct sum the 4-dimensional bundle inside the cotangent bundle, then the spinors on that thing—which is isomorphic and in fact semi-canonically isomorphic to both the tangent bundle and the cotangent bundle, being chimeric, it's isomorphic, but it's not fully canonically. It's only semi-canonically. So spinors on that will be identifiable with the spinors on [math]\displaystyle{ Y }[/math] as soon as you have a connection that completes this and makes it fully canonically isomorphic.

00:54:49
So the take home message, there is a spin bundle up on the bundle of all metrics, which is nearly the spinors on the tangent bundle, that exists without making a metric choice. And if you're really serious about quantum gravity, you should be very freaked out about the idea that once you quantize the metric, you've got a whole lot of pain, because the electron and the hadron bundles, and all the spin-1/2 matter, the medium in which these particles are disturbances, are excitations, doesn't really exist in the absence of a metric choice. If you allow the metric to become quantum and allow it to blink out, the spin-1, spin-0, and spin-2 particles may be indeterminate between observations. But the bundle itself, the medium, is indeterminate between observations of the metric for fermions. So now you're in a really different conceptual world. Everybody should want to free fermion bundles from dependence on the metric if they're serious about letting the metric blink out in some supposed quantum gravity regime.

Implications, Expectations, and Communication[edit]

00:56:05
Brian Keating: Let me ask you about that for a second. So it seems like this is a huge, you know, "Huge if true," I always like to say.

00:56:13
Eric Weinstein: Well we say that, but I don't know whether I just missed one hell of a meeting. I just don't understand why everybody isn't worried about—

00:56:20
Brian Keating: So this is huge, right? This is, what you're saying is that you can get spinors—

00:56:24
Eric Weinstein: If I haven't made a boneheaded mistake.

00:56:27
Brian Keating: Well, this is where I'm going to. I don't think you have, but I'm just a simple experimental cosmologist, okay?

00:56:33
Eric Weinstein: I'm just a podcast host.

00:56:33
Brian Keating: I traffic in [the] nuts and bolts of cosmological experiments, telescopes, as you know, detectors and fields. I am out of my depth in many cases, but this struck me like a freaking thunderbolt that you were deriving—essentially, spinors can be defined without choosing a metric. That is new. I don't think that any critic, any anonymous, pseudonymous, or anonanononymous person can really criticize that. I mean, that's just a fact. So why wouldn't physici—if it's not true, it would be, you know, almost surprising, but if it is true, why haven't physicists noticed this before and why aren't they making a bigger deal out of it? Partially, it might be your fault, because you haven't published this.

00:57:18
Eric Weinstein: Blame the victim.

00:57:21
Brian Keating: Who else?

00:57:22
Eric Weinstein: So what I usually hear about this is, people say "Oh, you don't understand, Jean-Pierre Bourguignon told us how to move spinors under variation of the metric." But he's varying the metric continuously, there's always a metric present. What if there's no metric for a little while?

00:57:46
Brian Keating: Which could be the universe before before God intervened.

00:57:50
Eric Weinstein: Are you going to do a Feynman integral over all variations of the metric? I mean, I don't know what kind of pain you're signing up for, but I'd certainly rather free—look, here's the basic statement. If we're serious about quantum gravity, we should be very serious about trying to get fermions that don't require their bundles to be dependent on the existence of a metric at all times. And I'm sure that either there's a brilliant explanation that I don't understand, and I'm eager to hear it, or it's a key sign that the community really dropped the ball. Remember, for example, that the Bohm–Aharonov effect—I'm sure that when, when Aharonov–Bohm said "Hey, shouldn't there be an effect of this zero field strength?" they probably thought 'Have I lost my mind?' I'm sure that Yang and Lee, when they proposed that maybe the weak force was left-right asymmetric, probably thought, 'Are we were going to be laughed at, did we just not understand what everybody else understood?' Physics gets things really spectacularly wrong occasionally, and I'm curious to know if this is one of those moments.

00:59:04
Brian Keating: Yeah. I mean, you might also say oh, there's 26 dimensions in heterotic string theory. That can't be right. No, it's only 10, or 11, or 5-brane, m-brane theory. I want to ask another question, which is frequently used in criticisms, both anonymous and nonymous, which is that this doesn't—

00:59:23
Eric Weinstein: I, can I actually, can I just say something? I really don't want to talk about anonymous trolls with PhDs criticizing the theory. And I also don't want to talk about non-constructive hit jobs on new theories. Last time I checked, physics was in a crisis that some people were admitting to and other people were sweeping under the rug.

00:59:43
Brian Keating: Okay, well—

00:59:44
Eric Weinstein: If you have a crisis—wait wait wait—if you have a crisis, for God's sakes [sic], open it up. We don't need one more talk from the same crowd of people who have been keynoting every conference of note for the last 30 years who haven't got the new ideas. Let's at least hear crazier, weirder, wilder people. And if you guys don't have the guts and courage to do it from inside the community, hear it from a podcast host.

01:00:10
Brian Keating: Okay, well, this is my podcast, and I do want to respond to these criticisms, because for me, I don't find them legitimate. And you can choose to be silent as is your want. No, it's rare to—

01:00:23
Eric Weinstein: No, I wish to punish dysfunctional cowards who attempt to snipe, pretending to be helpful. You can do better at it.

01:00:35
Brian Keating: I can do better as well. But I do want to say that this is maybe a general comment, not for pseudonymous and anonymous people, bananymous. But this is a general complaint that I've heard: it has to reproduce quantum theory. And I think, forget about that with regard to GU, it could be said about other theories, loop quantum gravity, etc. First of all, I think GU does produce what we would say is a relativistic quantum field theory in the Dirac equation, which is manifestly resplendent and produced and predicted. So I don't want to hear from you just yet, Eric, I do want to get your response. But this notion that a theory of everything has to subsume anything—I said this to our mutual friend, Stephon Alexander, professor at Brown University and esteemed cosmologist, and close friend to both Eric and myself, I said, "Look, I don't think it's valid to say that any theory of everything, string theory or whatever, has to predict every manifestation of physics," and this is where I take issue, and I make truck with Professor Kaku, who says things like, "The one-inch-long God equation will predict everything." I don't think that's possible, (A) I don't think it's useful to think about the goal of physics is to predict every phenomenon in physics.

01:01:54
Eric Weinstein: Because it's an incautious statement. Really what you're trying to say is that there's stuff that you should be able to read off in the basic setup of theory directly, and there's stuff that you should work your ass off in order to get from the theory. Now, you know, we don't see quarks running around free the way you might imagine, naively, you would if you were looking at the hadronic part of the Standard Model Lagrangian, and so you have to work pretty hard, I would imagine, in order to find these bound states that we call protons and neutrons, and try to understand infrared slavery, etc, etc. Now, that's part of the hazard of saying I can predict everything. No, even computationally, you don't think so. Really, it's just a question of, we should be able to recover everything that we've already done. And actually, I think that that's pretty fair.

01:02:48
Brian Keating: So even—

01:02:49
Eric Weinstein: I think there's a dumb way of doing it, where you try to say, "Show me this, or then you don't have anything." And I have to say, I encounter a tremendous amount of that from people who are old enough to drink, and it gives me pause as to who's raising the young. That's not the issue. The issue is, they're right, they should be saying "Look, here's what we know how to do, and you should be looking to recover what we already know how to do from what you're saying," and I think that's actually fair. There's a question of should you be able to do everything on day one? Should you be able to do it when you've been cut off for 27 years working completely on your own under totally weird circumstances, where every month you feel you get farther and farther away from the literature, and your brain hasn't spoken this language in a million years? Those are questions that I feel like—that's really sad, because people don't understand what the cost of isolation is. I do think, however, that working in a context with competent people who aren't constantly trying to rename everything after themselves, there's no question that that's a reasonable and fair thing, if we had a collegial world based on a desire to advance our understanding. And I'm happy if I fail at that with a collection of constructive colleagues to say that that's a black mark against the theory, that's fine.

01:04:20
Brian Keating: Now, when I look at the corresponding, shall we say, implications against string theory, I would say things like the swamp land, the multiverse problem, these may be issues that cause stillbirth in many people's minds. I've talked to you about Paul Steinhardt, the Einstein Professor of Natural Science at Princeton—he regards the string theory as essentially bad for society, not just for physics, not just for science, but bad for society because of the extravagance in a truest sense of the word, in a bad sense of the word, of the multiverse and string landscape. Now I know you're shaking your head—go ahead.

01:04:58
Eric Weinstein: No no no. Let me be very clear about it. We're wimping out from what needs to be said, and it's really important the community gets it right. I don't think string theory is a problem. string theory can't harm anyone, string theory doesn't—it's the string theorists when they're in their triumphalist mode, that it's an insufferable state of being. But even then, you know, I'm sure Feynman was insufferable, and I think Murray Gell-Mann was insufferable, and Pauli was pretty insufferable. We've had insufferable members of our community for a very long time, and we should not be getting rid of insufferable people. The problem is, what happens when people become insufferable and they don't constantly check in with the unforgiving nature of the universe. I mean, Pauli predicted the neutrino in an insufferable fashion.

01:05:58
Brian Keating: And apologized. He apologized profusely, "I've done something which should never be done." Now, I asked you though, should string theory—let's just be neutral to GU for a second. Should string theory, from string theory, emerge the Aharonov–Bohm effect? I mean, a true theory of everything, it would, right?

01:06:19
Eric Weinstein: Look, and if it took a while to recover certain features of the world that you had in an effective theory—I mean, look, let's put it this way. If you look at Marshallian demand in economic theory, should you be able to predict that from the Lagrangian of the universe? No, it's in a different strata of the world. You should be able to predict things that are within the adjacent strata of the theory, and then you might have to appeal to some higher effective theory.

01:07:00
Look, I want to defend both the string theorists and string theory. These are incredibly smart people who found some real structure, and who never knew when to quit when it came to trumpeting just how much better string theory is than everything else. Even there, they had a point. They were smarter and deeper, in general, than everyone else. They just weren't as good as they claimed to be, and they weren't as successful as they claimed to be, and what they did succeed that they didn't want to take credit for, because it was really mathematics done in physics departments rather than physics.

01:07:34
So we have a problem that sociologically, nobody wants to say that the Institute for Advanced Study has the smartest guys around and a lot of what they do isn't physics, in standard terms, it's the mathematics of physics. These are uncomfortable truths, just the same way that it's uncomfortable that we're taking seriously somebody who's been out of the field for 27 years. But these are end times, we're having end time conversations. I think that it's—we don't need to be mean about it. I think it just needs to be more honest.

Concept Animations[edit]

01:08:08
Brian Keating: Okay. With that, I give some applause here. Let's see if we can hear that. [Applause sound effect] Got some applause, Eric. A smattering. That just was a smattering. I want to take a pause for the cause, and to have a pause to recognize our guest today is the esteemed Dr. Eric Weinstein, who is a seeker after truth, a seeker after my own heart in the authentic tradition of the old one—his namesake, Albert Wein... Now they say this is not a serious podcast until you break out the puppets. Now I know Rogan has a supply of bows and M16's, and all sorts of other things. I don't have any of those accoutrements, I only have my sock puppets and my gelt Nobel Prize. But, I do want to say that this is a special conversation with Eric, because it really fulfills a promise that was made basically a year ago, and then again about six months ago on this podcast, which is to release a stunning amount of new technical details, and you've really surpassed that.

01:09:12
Our mutual friend James Altucher, podcaster extraordinaire, he says that you should never under promise and over deliver, you should never under promise and under deliver. You should over promise and over deliver. Meaning that if you say you're going to get it done in three months and get a million customers, you should get it done in one month and get ten million customers, or as one Peter Thiel said once, what do you think will require ten years but could be done in six months. So, what you've done is released a tremendous amount of technical information that will be fully released at some point to the public. But also, I want to take our audience through some of these delightful animations. I put the link in the chat for now, but I'm going to share my screen right now. Hopefully you can see it as well, Eric. These are now movies I want you to animate—I'll put you in the lower corner. Let's see if I can do that, I'll do that in a second. Let's see, I'll add Eric. Nope, I'll swap these. There we go. I'm going to swap Eric, if you're willing to swap. There we go. I want to walk us through—which which one of these many videos should we should we take a look at? I was fascinated by the Shiab, but that's just my—

01:10:27
Eric Weinstein: Let's do the first three.

01:10:29
Brian Keating: Okay, so the first one is called an Ein—

01:10:31
Eric Weinstein: Go to Einstein's Great Insight. We're going to do this for people who are somewhat physics-minded, but who like to complain that none of this is understandable. By the way, there are some names associated with these videos. Brooke Dallas has been shepherding the project. Brandon Stone has been incredibly helpful technically. Boqu, a mysterious German man who animates many of these things. There's a list of people who've contributed. Tim, the mirthless swagman, from Australia, a math student down there. So, what they've done is they've tried to interpret what it is that I'm saying, because I tend, because of learning issues, to not think symbolically—stop, Brian.

01:11:14
Brian Keating: Yeah.

01:11:14
Eric Weinstein: Let's blow that up. Full screen

01:11:17
Brian Keating: It is full screen here, yeah.

Ship in a Bottle Animations[edit]

01:11:19
Eric Weinstein: Okay. That ship that you're seeing is called curvature. It has three masts because it has three irreducible components, usually. One mast is called Weyl curvature, one mast is called traceless Ricci curvature, and one mass is called Ricci scalar. The first greatest insight of the 20th century was the way in which we could feed back the curvature of the Levi-Civita connection into being a co-vector field on the space of all metrics. This is depicted as a boat going into a bottle that has a rather wide opening. So let's run the animation.

01:12:05
Brian Keating: Okay.

01:12:06
Eric Weinstein: So we've got a metric. The metric has a connection, the connection produces curvature that's Riemannian. We find that by identities, it's got three components. It tries to go towards metrics and the Weyl curvature is snapped off. Afterwards, the scalar curvature is lowered somewhat, or adjusted, by scalar curvature over 2 times [math]\displaystyle{ g_{\mu \nu} }[/math]. And so symbolically, what we've done is we've said Einstein threw away the Weyl curvature, readjusted the Ricci scalar curvature, and fed metric information through to the Levi-Civita connection, through to the Riemann curvature tensor, and then played these projection games to feed it back to the space of metrics. And that particular combination is perpendicular to the action of the diffeomorphism group on the space of all metrics, leading to a divergence free condition via our friend the Bianchi identity.

01:13:03
Now, why can't we do that and feed this information back to the space of connections rather than the space of metrics because we would love to link spacetime games with gauge potential games. So, let's see whether General Relativity and gauge theory have an incompatibility problem as we try to play the same game. We start off with the Riemann curvature tensor, but now the neck is narrower. What's really going on is that this is kind of evocative of trying to feed it into the space of connections, but the gauge group acts differently on two different factors: namely, if connections are ad-valued 1-forms and curvature is an ad- or Lie-algebra-valued 2-form.

01:13:57
The problem here is the gauge transformations act on the Lie algebra component and don't touch the form component. But Einsteinian projection, or contraction, or summing over [math]\displaystyle{ g_{\mu \nu} }[/math] indices, is democratic: it deals simultaneously with the form piece and the Lie algebra piece. So if you treat only the Lie algebra piece under a gauge transformation and you don't touch the form piece, then contraction followed by gauge transformation will never be the same thing as gauge transformation followed by contraction. And so that's the puzzle, which is if Geometric Unity is really about the idea of trying to say maybe it's not so much quantizing gravity, maybe it's a fight between the different geometry of Riemann and Ehresmann, because gauge transformations are Ehresmannian geometry but contractions are Riemannian geometry.

01:14:57
So here's a GU approach, how do you get geometric harmony between General Relativity and gauge theory when you have the ship in a bottle problem? This is almost a tight analogy. You've got the curvature tensor, you apply a gauge transformation to two of the masts and you pass them through into ad-valued [math]\displaystyle{ (d-1) }[/math]-forms, and then you do an inverse gauge transformation, which is exactly how you do the ship in the bottle trick—by the way, Brian gave me a wonderful ship in a bottle, thank you very much—raising the mast inside. And then you can potentially, if need be, adjust one of the two masts again in order to get agreement.

01:15:40
So in part, the idea is how do you get harmony? What you need to do is to promote the gauge transformations initially to field content in order to make sure that you're carrying around enough information, effectively, to ensure that contraction is compatible with gauge transformation. Now, that is a very tight idea of how these operators function inside of the theory.

Gauge Theories as Calculus Done Right Animations[edit]

01:16:18
[Keating pulls up "Penrose-like steps" video]

01:16:19
Well this is just—for some reason, whenever we talk about gauge theories, we don't give people very concrete examples. Many of you who are not professionals will not know what a gauge theory is. May I make a recommendation, Brian?

01:16:31
Brian Keating: Yeah, of course.

01:16:33
Eric Weinstein: Let's go to another animation, which is something like Gauge Theories as Calculus Done Right, and blow that up as big as it can be before starting the animation. Okay, start the animation. Let's imagine that we have a salary that is constant in dollar terms over time, [and] that somebody is facing inflationary pressures on their basket of goods. Now the question is—pause please. What we now have is a $10 an hour salary, and if we claim that it's constant, constant means derivative equals zero. But, we know that it's not constant purchasing power. So we have two notions of constancy, how are they related? Let's go back to that please.

01:17:32
We do a gauge transformation. And what you see—pause please. You now see that these little hash lines are the reference levels that we call a connection, and we decide that rise over run should not be measured from a naive horizontal, but should be measured instead from a custom reference level represented by the hash marks. Now, if you let it go a little bit, and then stop it, stop. Now you see that derivative equals zero, if we measure rise over run above the hash marks, is a salary that keeps pace with inflation. And the current $10 an hour is actually a negative derivative because the rise over run is measured beneath those hash lines. That situation is actually an application of gauge theory to a very simple problem in economics, completely depicted by stretching the fibers in the x-y plane. And if you look online right now and say "What's a gauge theory?" you'll be bamboozled by a bunch of stuff that nobody can understand unless they're actually insiders.

01:18:49
So I think it's very interesting that again, just as it was elementary to ask the question, "What happens to the fermion medium while we're blinking out the supposedly quantum metric?" why is it that we don't actually explain to anyone what a gauge transformation and visualize it? I'm very proud of our team for taking this very simple example and showing what a gauge field is—it's those little hash lines, effectively. Those things in higher dimensions would be the electromagnetic potential, which becomes the photon under quantization. And if you're thinking about QED (quantum electrodynamics), effectively, the electron is a function and the photon is a derivative, because what you're specifying is the levels above which you're going to measure rise over run. Now you can go back to the original floating plane.

01:19:41
Brian Keating: Floating plane...

01:19:42
Eric Weinstein: What you were doing before.

Digression on Academic Misbehavior[edit]

01:19:43
Brian Keating: I just want to take a second here. This is Brian Keating now speaking. So, if you look up Juan Maldacena, you will find only one podcast that he's ever been on, and that is the Into the Impossible podcast. If you look up gauge theory and an intuitive way to understand gauge theory, something like that, you'll come up with this really brilliant economic analogy that sounds like Eric has copied from from Juan Maldacena. And in fact, this came up recently, where people were talking about inflation-stabilized items and Bitcoin and so forth, and then—it was very frustrating to me, and I imagine much more so for Eric, although he doesn't have to comment, he's too much of a gentleman. This is Eric's work. This gauge theory applied to economic transactions.

01:20:33
Eric Weinstein: Eric and Pia.

01:20:34
Brian Keating: Eric and Pia Malaney. Yep, Pia Malaney, of course, the beautiful talented wife of Eric Weinstein. Eric is known as the husband of Pia Malaney, mostly. This work is brilliant and is deserving of attention in its own right, independent of the brilliance of it as an analogy to explain a very complicated subject such as gauge theory, or a very simple subject like calculus, as Eric is now explaining to us. I wanted to say that, you don't have to respond if you don't want to Eric, I find it very frustrating when I see "Oh, Eric, you've got to learn what Maldacena said," I'm like F you. That's very frustrating to me.

01:21:17
Eric Weinstein: That's what was hurtful, because Juan knew that he had gotten this—knew about Pia Malaney, he needed to reference her. He did reference her, but in a very slight, minimal way in a [Inaudible] version.

01:21:33
Brian Keating: It's a footnote. It's a footnote. He knows better than that.

01:21:37
Eric Weinstein: The problem that I'm having with it is that the professional community does not understand that it has impulses that it hasn't faced, which is that it tends to brutalize those that it doesn't need to cite, that it doesn't see. It just doesn't see people. And so to have—look, I'm a huge Juan Maldacena fan as are we all, but I'm not going to sit around and have people say "What you really need to do is to listen to Juan Maldacena, whose brilliance knows no bounds. He did something really profound about markets and gauge theory," because quite frankly, Pia Malaney deserved to have an entire career built around it. I think it could easily be the most deep insight in mathematical economics in the last 25 to 50 years. Please show me another, given that the Marginal Revolution, originally, was the penetration of differential calculus into economics. Her thesis, which is largely joint work, but was not even allowed to be what it was supposed to be, rebased the field of economics on gauge theory as the correct form of calculus. I'll tell you what, I don't really want to bitch about Juan Maldacena, but what I would really love to do is to have Juan Maldacena, who showed so much excitement when I confronted him about this—he says, "Oh, you know who that is?" because he had no idea who Malaney was. It would be really great if Juan Maldacena did this work, and I won't say another word this podcast about it.

01:23:16
Brian Keating: Okay. And I will say only one word because it's my podcast, and I can do whatever the hell I want. I had on Cumrun Vafa, as you know, who wrote a book called Puzzles to Unwrap the Universe, in which he cites Juan Maldacena. I called him on that. I said this is actually original work by Pia Malaney, Eric Weinstein, and it almost doesn't matter. And I find that very frustrating, because the very same people—and you don't have to respond. Please don't respond. Again, I'm a blowhard on my own podcast. It's one of our prerogatives. We get so little of these things and treats in life. But I find it very disingenuous of the community. I love Cumrun too, but to say that "This isn't serious Eric, you have to cite this paper, you have to put out a paper about GU, you've only done things on Joe Rogan," I find that disingenuous. You don't have to respond. Let's go on.

01:24:09
Eric Weinstein: What I will say is this. When you have gatekeepers in the form of advisors, if you have job market meetings, where people wield incredible power and they hold other people's careers in the palm of their hand—if you use these places to crush people, you have no right to comment after the fact as to why are these people behaving bizarrely and strangely. Because in essence, whether you submit things to journals and have a perfectly reasonable relationship with peer review, or whether you find that peer review is basically a tool to exclude you, and your insights, and your claims from the world, depends in large measure on who you are, where you're coming from. It's human dependent, it's not independent of who submits and how protected they are.

01:24:58
The thing that I want to get across is that the community is producing trauma in people and then claiming that it's paranoia. You have to recognize that trauma and paranoia look exactly the same when you can't see what the source of it is. If you want to understand what happened to this theory, read The Physics of Wall Street by James Weatherall, chapter 10 and the epilogue. It's rather clear about the fact that four gentlemen and one lady tried to steal a trillion dollars over 10 years by pretending to fix the CPI because social security and tax brackets were indexed. They came up with 1.1% adjustment that would be needed, and then they broke into two teams to find exactly out the 1.1% that they wanted. This was admitted to by Robert Gordon. And, the most brilliant thesis that probably came through Harvard in terms of mathematical economics was destroyed so that Daniel Patrick Moynihan and Bob Packwood could have a back end run around the third rail of politics, which is slashing benefits and raising taxes, using economists to destroy, funnily enough, a bright promising woman of color from the developing world in an essentially all male field. These people should pay with their reputation.

Concept Animations 2[edit]

01:26:31
Brian Keating: Okay, I want to lighten things up again. Let's talk about Jeffrey Epstein. No, I'm just kidding. I made you laugh, come on. That's a big accomplishment.

01:26:41
Eric Weinstein: That was good. I like it.

01:26:42
Brian Keating: Alright, let's look at one last video here. Let me call up a—let's go to the videotape as they say. Go here, I'm gonna go to Safari, Rastafari... Nope, it's not coming up. Oh, maybe that's because it already thinks that we've done it, let's see here. All right, zoom out. I'm gonna...

01:27:07
Eric Weinstein: Do you want to do an observerse one, down at the bottom?

01:27:12
Brian Keating: Yeah, I'm trying to get up the—tell me when to stop here. Well you can't see it, right?

01:27:20
Eric Weinstein: I can't see anything.

01:27:21
Brian Keating: Let me let me get my screen back here. Let me kill that. Let me kill... what else is going on here? Screen share, show Safari. Show primary display, secondary display, there we go. Can you see that?

01:27:40
Eric Weinstein: Yeah.

01:27:41
Brian Keating: Okay. So at the bottom, I see 5D Observerse, Spinor Dance... Which one would you like? Observerse 5D?

01:27:53
Eric Weinstein: Let's do 5D. Yeah, I think I'll explain what they're trying to depict. It's not exactly how I would have done it, but keep in mind that these are artists who've been trying to learn what this is by bypassing typical—okay, so pause it.

01:28:15
Brian Keating: Yeah.

01:28:16
Eric Weinstein: Can we get rid of that bottom bar?

01:28:18
Brian Keating: Yeah, it's, they need to disable it on their side, but I can kill it off here. There we go.

01:28:23
Eric Weinstein: Okay. And can you blow that up? Or is that as blown up as it can go?

01:28:29
Brian Keating: Let's see here. I think it's fairly blown up.

5D Observerse Animation and Pati–Salam Connection[edit]

01:28:33
Eric Weinstein: Alright. Imagine that that torus that you see in the lower left corner of the screen is a 2-dimensional model, toy model, of spacetime. So going around through the center is like Groundhog Day, you come back to the same place and it's a repeating time cycle, and space is simply a circle. Now in such a world, we would normally think of quantum field theory or gravity as taking place on that object. You'd have fields, you'd have effectively functions called sections on that object, and what you're seeing here is something that's very hard to picture because it's 5-dimensional, but one trick here is because the torus has a property called parallelizability... The object on the right is a depiction of a metric. Each point that isn't on one of those two sheets is a potential metric at any given point on the torus. So in other words, if a metric is a symmetric non-degenerate 2-tensor, if you think of it as a matrix, it would be of the form [math]\displaystyle{ \begin{bmatrix} x & z \\ z & y \\ \end{bmatrix} }[/math]. Non-degenerate means that [math]\displaystyle{ xy - z^2 \ne 0 }[/math]. So that's what's cutting out that variety, if you will, the zeros of the of the determinant would be points, given that there are 3 degrees of freedom in the metric.

01:30:21
So instead of actually having a metric spacetime, GU would say replace the torus by the entire space in that sort of hourglassy region. So the top region would be like space-space metrics, the bottom below that sort of weird, diaphanous scarf is time-time metrics, and the weird middle region, which is sort of around that singularity, would be space-time metrics. Every way you can stick that donut into that middle region without touching one of those two sheets is a valid spacetime metric. And what GU would do is to say don't only dance on the points of the 2-dimensional torus—again, the surface is 2-dimensional, even though it seems to be 3-dimensional to naive investigation—you should actually have fields that are dancing on all of the points of the torus and, simultaneously, all of the points in that middle region of what we call the Diablo diagram, no to the right. To the right. Yep.

01:31:36
So every point in that region is in play, and if you mapped—imagine that the stuff in that weird hourglassy region on the far right was like very warm and on the far left was very cold. Then if you map the torus in to the far left region, it would show up as being cold. If you mapped it into the far right region, you'd see it as being very hot. So every way of mapping the torus in pulls back different information from that hourglassy region. That is in large measure, in part, one of the things that may be going on with the illusion of many worlds, is that what you're seeing is that the metric may be capable of pulling back data that is dancing on the space of all metrics as well as the space of all points on the original manifold [math]\displaystyle{ X }[/math]. So in this case, you've got 2 degrees of freedom on the torus, you've got 3 degrees of freedom around the hourglass, and [math]\displaystyle{ 2 + 3 = 5 }[/math].

01:32:38
Now notice that thing up in the top left, which is a ruler-protractor combination that I just gave a copy [of] to Joe Rogan. Those two sliders are recalibrations of what it means to be one unit. And that protractor is a recalibration of what you're going to define to be 90 degrees. So every way of keeping that bottom arm in a single horizontal position, moving the top arm, and moving the two sliders, that's 3 degrees of freedom in the space of metrics. So that's a different depiction of the space of metrics.

01:33:15
So the big take home from the restrictive version of GU that we're exploring here is that if you allow fields to dance on the space of metric apparatus—measurement apparatus—then the paradoxes of measurement start to make a lot more sense. You could also, potentially, try to keep the metric classical, because we have two spaces. We have a space downstairs [math]\displaystyle{ X }[/math], which is just the torus, and we have a space upstairs, which is the torus, in this case, cross the hourglass region, as long as it doesn't touch the two sheets. So you've got a 5-dimensional manifold hovering over a 2-dimensional manifold, and fields on the 5-dimensional manifold will be perceived on the 2-dimensional manifold when you pull them back via a particular Einsteinian spacetime as fields on the tangent bundle of what you will call spacetime, together with fields on the normal bundle inside of the 5 dimensions.

01:34:18
The normal bundle of a 2-dimensional manifold in a 5-dimensional space is 3-dimensional, so you're gonna see fields that look like spinors on 2 dimensions tensor spinors on 3 dimensions. If you were in 4 dimensions, make that torus in your mind represent a 4-dimensional spacetime, then that Diablo region would be a 10-dimensional region of metrics, because 4x4 matrices that are symmetric have [math]\displaystyle{ \frac{4^2 + 4}{2} }[/math] [Inaudible] for different degrees of freedom. In other words, you get a 10-dimensional normal bundle.

01:34:57
Now you'll notice that if you have ordinary spinors on 14-dimensional space and you pull them back via a metric, which is a mapping of 4 into 14, it looks like spinors on the 4-dimensional space tensor spinors on the 10-dimensional normal bundle. If the normal bundle inherits the Frobenius metric from [math]\displaystyle{ X(1,3) }[/math], and you glue in the trace piece in the right way—well, if you glue it in the wrong way, you'd get a [math]\displaystyle{ (7,3) }[/math] metric on the normal bundle. But if you glue it in the right way, you'd get a [math]\displaystyle{ (6,4) }[/math] metric on the normal bundle.

01:35:35
[math]\displaystyle{ \text{Spin}(6,4) }[/math] is a sort of nasty non-compact group, so you might want to break to its maximal compact subgroup like Witten and Bar-Natan discuss. And the interesting thing about [math]\displaystyle{ \text{Spin}(6,4) }[/math] is that it has different names. By low-dimensional isomorphisms, [math]\displaystyle{ \text{Spin}(6) }[/math] is the same thing as [math]\displaystyle{ \text{SU}(4) }[/math]. [math]\displaystyle{ \text{Spin}(4) }[/math] is the same thing as [math]\displaystyle{ \text{SU}(2) \times \text{SU}(2) }[/math]. And [math]\displaystyle{ \text{SU}(4) \times \text{SU}(2) \times \text{SU}(2) }[/math] is the Pati–Salam theory. So you can argue that ordinary spinors on the induced metric in 14 dimensions, glued in the right way, pull back as Pati–Salam. And I don't know if anyone's ever discussed the connection between Einstein and Pati and Salam.

01:36:29
Brian Keating: No. No.

01:36:31
Eric Weinstein: Well no, I can't say no, I don't know of it.

01:36:33
Brian Keating: I don't know, that's what I'm saying. People have brought it up, but yes, has it?

01:36:39
Eric Weinstein: Has anyone? I don't know.

01:36:41
Brian Keating: I don't know. Yeah.

01:36:42
Eric Weinstein: So the point is that spinors on 14 look like spinors on 4 tensor spinors on some version of 10.

01:36:50
Brian Keating: Yeah.

01:36:51
Eric Weinstein: And whether you're talking about [math]\displaystyle{ \text{Spin}(10) }[/math] models, [math]\displaystyle{ \text{SU}(5) }[/math] models, or [math]\displaystyle{ \text{SU}(4) \times \text{SU}(2) \times \text{SU}(2) }[/math], which is [math]\displaystyle{ \text{Spin}(6) \times \text{Spin}(4) }[/math], isn't that exactly what we see in the Standard Model? So Frank Wilczek—let me just see if I can find this beautiful quote from him, because he definitely brought this up. And what I recently did when I had him on my podcast, which we haven't released—so, if we go over to my screen share...

01:37:30
Brian Keating: Give me one second. Let me do this. Here we go. And... There we go. Yep.

01:37:42
Eric Weinstein: Let me read it. "A particularly intriguing feature of [math]\displaystyle{ \text{SO}(10) }[/math]," which is really [math]\displaystyle{ \text{Spin}(10) }[/math]spin 10, or it could be [math]\displaystyle{ \text{Spin}(6,4) }[/math], "is its spinor representation, used to house the quarks and leptons, in which the states have a simple representation in terms of basis states labeled by a set of "+" and "-" signs. Perhaps this suggests composite structure." Now here's the sentence that just floored me. "Alternatively, one could wonder whether the occurrence of spinors both in internal space and in space-time is more than a coincidence." And then he pulls back immediately, "These are just intriguing facts; they are not presently incorporated in any compelling theoretical framework as far as I know." Geometric Unity is that compelling framework.

01:38:26
Brian Keating: Awesome. Very interesting. So as we wrap up, I do want to see if there are any other videos you'd like to show that would help the reader, or again, I'm going to put this in the chat box so people can peruse it. I did put it in the actual YouTube box description, so people can find that at their leisure. Let me see here. Oh I see what's going on.

Geometric Unity Document[edit]

01:38:56
Eric Weinstein: Well I should say that I... Look, let's be honest. I said I was going to release a document, and clearly we haven't. Okay, April Fool's. April Fool's.

01:38:57
Brian Keating: Uh oh, the big reveal!

01:39:17
Eric Weinstein: Go to geometricunity.org.

01:39:21
Brian Keating: geometricunity.org.

01:39:22
Eric Weinstein: And, yeah, call that up. And then Brian, why don't you be the first to put your email address in to request a copy? I wouldn't call it a paper, I'd call it a draft. One of the things I'm looking to do is I'm looking to get constructive feedback from people who want to help me succeed, as opposed to people who just want to be dicks and take me down, because that's just, to be honest, not very interesting to me, and I've had a little taste of that, and I'm not that interested. What I would love is to bring your positive energy. Download it, read it, recognize that more or less, I've been cobbling this together from a million and one different scraps, and that my ability to talk in this way has been degrading for years because I have no one to talk to. I'm not in a department, I'm doing this completely on my own. And I was a little bit frightened to figure out just how much I'd forgotten.

01:40:20
So we're still finding scraps of paper, and files on old discs, and things like that. I hope that the notation is getting more and more standard, that there are fewer errors. But there's clearly, you know, this is basically me going back to 1983, '84, and all the time in between, where mostly I didn't talk about this with anybody. And this has been really terrifying, because you know, I'm not a physicist, I don't come from this community. I revere the community. I don't think the community has been behaving well recently, I don't love saying that. But I think the community is in a desperate situation, and let's find out whether I have anything to say or I'm just blowing hot air. I'm not afraid of that. But you know, what would really be meaningful to me is for people to bring kindness, benefit of the doubt, hope, and recognition that it's pretty tough to try to do all this on your own, Be constructive and take a look. I think there are two email addresses on the paper in draft form, one for technical feedback and one for general feedback. So I hope that there's a lot of food for thought.

01:41:43
I do think that—let me just close this out. I think it's a coherent story. I think it's the first time I've ever heard a coherent story about how a very simple beginning would produce something that would look like our world. There are things that I would call predictions in it, that talk about what internal quantum numbers you would expect to find, likely next in terms of, there's much more matter, there's matter that should be dark, there's matter that might be luminous but not at the right energy level yet. You would have to, in order to compute with it, be able to figure out what fields have acquired VEVs (vacuum expectation values) and where we are in anthropic spaces in some places. But the internal coherence is much sharper than a few, you know—there's still some things that I'm trying to locate my favorite version of. One is the Shiab operator. I know how to produce Shiab operators in general, but I had a sheet of paper with—do you remember paper with feeds, with holes on either side?

01:42:44
Brian Keating: Oh yeah, loose leaf, oh feed, oh printer paper. Printer paper.

01:42:47
Eric Weinstein: Not loose leaf. Printer paper.

01:42:49
Brian Keating: Dot matrix.

01:42:50
Eric Weinstein: Yeah. So I did some calculations in representation theory that came up with the projections that I used to use that I'm looking for. And the thing that I remember is that they've got yellow highlighter and these perforated holes on either side. I haven't been able to find it yet.

Conclusion[edit]

01:43:08
So it's a very long process, taking about 37 years of speculation, sometimes more active than others, and trying to put it in one document. So I would really appreciate it if people wanted to take a gander through it. Try to see some of the ideas, and recognize that if we are going to get off this planet with its hydrogen bombs and crazy leaders, and diversify and take some some bets, rockets are not going to do it. There is no real "Mars or Bust", or "Occupy Mars" strategy. There's one quote that keeps coming back to me, "Our home is in the stars or not at all." If we're gonna sit here on a hot, crowded planet with thermonuclear weapons, maybe we have hundreds of years, but we don't have thousands. If we're going to get off this planet and go someplace interesting, we're going to have to recognize that we don't have the source code yet in Einstein, and it's very limiting, and we're going to have to actually say, "What is the source code?" And if it turns out that we can find it, we're gonna have to be good stewards, and we're not going to do the same thing that we've been doing by handing the stuff over to leaders who don't take seriously the burdens of godlike powers that we the technical people bestowed. So Brian, thanks for having me on, and it's a pleasure to interact with your audience.

01:44:29
Brian Keating: Eric, it's a pleasure to have you on the show. As always, you're welcome back anytime. I do love the fact that you made this promise back in early or late December of 2020, that year that may it soon be forgotten.

01:44:47
Eric Weinstein: I didn't promise, I said I was gonna try. I said I was gonna try.

01:44:52
Brian Keating: That's right. Well you succeeded, you succeeded for sure, Eric. I want to thank you for your generosity of time, and spirit, and advice that you've given to me. I hope I can help to serve you in this, wherever this project may take you. It's now out of your hands, it's into the world, and it's going to hopefully sprout many many delightful new discoveries for the benefit of all mankind as our friend Alfred Nobel so warmly engendered upon the world. Eric, best of luck, congratulations. We'll do a part three next year on this date, on this auspicious date, and let it forever be known as a day of famy, not infamy, for years to come in physics, if we can follow the lead of the generous, the mercurial, the genierrific, Eric Weinstein. Thank you so much, Eric. Enjoy the day, and we look forward to seeing you on Joe Rogan... tomorrow? Or when will that podcast be out?

01:45:45
Eric Weinstein: I think so, L'Shana Haba'ah in the electron layer.

01:45:49
Brian Keating: Okay, inshallah. Goodnight everybody. Please do subscribe and like this podcast, we have Michio Kaku coming up. John Mather, winner of the 2006 Nobel Prize—[Video cuts]—Magnificent ideas to the space, to make it safe for new ideas and for creativity, because we do have this one universe, this one life, and it is eminently precious. So for now, thanking you all, enjoy the rest of your evening, and thanking you Eric, here's a musical outro from our friend Miguel Tully, proprietor of the Yeti Tears podcast, Spotify, and YouTube channel. Good night, everybody.