Difference between revisions of "15: Garrett Lisi - My Arch-nemesis, Myself"
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== Description ==
== Description ==
[[File:ThePortal-Ep15 GarrettLisi-EricWeinstein.png|600px|thumb|right|Eric Weinstein (right) talking with Garrett Lisi (left) on episode 15 of The Portal podcast]]
[[File:ThePortal-Ep15 GarrettLisi-EricWeinstein.png|600px|thumb|right|Eric Weinstein (right) talking with Garrett Lisi (left) on episode 15 of The Portal podcast]]
Revision as of 14:55, 3 July 2020
Garrett Lisi, the so called "Surf Bum with a Theory of Everything (or T.O.E.)", is a PhD theoretical physicist who has refused to be captured by the theoretical physics community. By making shrewd investments, he has avoided holding meaningful employment for his entire adult life. Instead, he lives in Maui and travels the world chasing the perfect wave.
In this episode Garrett and Eric sit down to discuss the current status of Garrett's ideas for a final theory based on a mysterious object called E8, perhaps the oddest of mathematical symmetries to be found in the universe.
Garrett and Eric have held each other in mutual “contempt” for over a decade. By vacationing together and staying in each others' homes, they had hoped to hone and deepen their mutual disgust for each other's ideas. However, as the theoretical physics community moved away from actually trying to unify our incompatible models of the physical world, it became intellectually unmoored, and drifted toward a culture of performative Cargo Cult Physics. The antagonists were thus forced by necessity to develop a begrudging admiration for each other's iconoclasm and unwillingness to give up on the original dream of Einstein to unify and understand our world.
The discussion is rough but a fairly accurate depiction of scientific relationships belonging to a type that is generally not shown to the public. This may be uncomfortable for those who have been habituated to NOVA, The Elegant Universe, or other shows produced for mass consumption. We apologize in advance.
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- I fell into The Portal! Got harassed by Eric for two hours. Didn't particularly enjoy it, but others might.
References in the Episode
About Garrett Lisi:
ERIC WEINSTEIN - Hello you're queued up to enter the portal but I thought I'd say a few words before this episode in general
When we present science in front of the public we do it in one of two ways. Either we talk in an incredibly hand-wavy way about very speculative ideas like string theory, or we have a sort of a corpse of previous scientific thought that has been specifically arranged for public viewing.
It's not really science the way we do science, it's kind of a denatured version to make sure that we don't lose anybody because the public is famously supposed to be squeamish about anything involving equations, abstractions or jargon. In this episode we try to well do something different.
I'm actually having a conversation with Garrett here he's updating me on where his thinking has gone with respect to unifying physics
now it's very unusual for anyone to try to unify physics and I have a tremendous amount of respect for Garrett even though I don't think his theories are going to work I make no secret of this I'm not saying anything behind his back but he is in some sense Theodore Roosevelt's man in the arena he actually is trying to take on the general problem of the cosmos and even though I don't think he's succeeding he has my profound admiration for simply suiting up and trying.
most people, in fact almost everyone I know, does not attempt to do what he is doing and for that he has my admiration and respect now with that admiration respect comes a desire not to be mean but to actually push him on his theory because I don't want to see him wasting his time and I feel that when you're outside of the university system there's almost no one who takes your research seriously. So while there is an aspect of tongue-in-cheek with respect to us being each other's arch-nemesis there's actually something quite serious about it
I don't necessarily like the path that he's going down and I don't know that I really believe that he's going to get anywhere productive but I do think that he's an inspiration to us all simply for trying in an era where everyone else seems to have given up.
I hope you enjoyed this episode and I hope that you understand that it is an experiment. I'm trusting you guys to listen in on something which is much closer to actual science than what usually presented with I hope you like it, stay tuned
WEIN - you found the portal I'm your host Eric Weinstein and I'm here today with my arch-nemesis physicist Garrett Lisi
Garrett, welcome to the portal
GARRETT LISI - thanks for having me on Eric you're a brave man
W - well I would say you're a brave man coming into the lion's den so thank you for coming by for those who don't know who you are or what this issue of being arch-nemesis is about what what could you do to inform our listeners and viewers about who you are and what our relationship might be
LISI - all right well we have a many disturbing similarities in that we did fairly well in school we got our PhDs but then we left academia and but maintained an interest in fundamental physics and kept pursuing this on our own however there are some distinctions in that you went into the finance world and I went into being a surf bum
W - yes that's not that similar also you are you have a PhD in physics proper whereas I have one in mathematics so I would say advantage Lisi but then I have one from a more typically powerhouse school you have one from one that's a little bit off of that main corridor that maybe got up caught up in string theory and the the fads that propel the field but I think what's been very interesting to me is that in all of theoretical physics which everyone is quite interested in - you still find people publishing books on quantum theory and all of the spookiness weirdness and beauty that constitutes theoretical physics - it feels to me that almost no one is pursuing actual theories of everything. We talk about theories of everything all the time but that the courage to actually put forward anything that even remotely resembles the theory of everything, almost nobody is willing to do that would you say that that's a fair statement
L - yeah it's a very fair statement and the the main reason for that is because it's such a hard problem that you pretty much have to be a megalomaniac just to tackle it or to think you have a chance of succeeding at it
W - well I think that's a weird statement. Like if you're doing if you're going to throw away your life on issues of theoretical physics what is it that you would imagine people would think that they were doing like if you're not going for the brass ring why enter that field
L - well I think that a lot of people in physics are doing the usual thing where they encounter a problem and try to solve it and try to proceed incrementally and that's how actually I got wrapped up in this is I identified a problem with electrons in their description in fundamental physics it was something about it that really I didn't like it just didn't just didn't feel right to me and I got wrapped up in solving that, you know, one aspect of this big picture I didn't go off trying to think "oh I'm really going to tackle this problem of coming up with a theory of everything" because you you you have to be somewhat of a lunatic to take that on it's like you know I trying to prove some theorem in mathematics it has been stagnant for hundreds of years it's just you know you're probably not going to succeed and you'd probably just be frustrated with the attempt.
You have to have huge ego to even think about it, right, and also there's a lot of discouragement. Students are actively discouraged from tackling such problems because the professors who came before them and know a little bit more about the field know just how hard it is to make progress even on small problems and that making progress on a huge one is just insurmountable, so they try to actively discourage their students from from going into fundamental problems in Physics because they they haven't had success themselves so they're they're trying to be protective of their students that way.
W - so maybe just to set this up and I should say to regular listeners and viewers of the portal this is intended to be something of a transitional episode. So that the entire podcast is an experiment and you know other other people have shows and there's a concept of professionalism. I don't think that's what we're striving for here at the portal, this is really untested. We're going to experiment with our advertising models. We're going to experiment with what the traffic will bear when it comes to intellectual discussions without spoon-feeding everything to the audience, realizing that some people may get left behind. In fact the host may get left behind, we don't know.
L - I hope not
W - but no it's quite possible and what we've done is we've done a series of interviews to begin the podcast to just establish that we can have conversations that people want to tune into and get great guests in that chair where people may not have even heard of the person before but hopefully walk away feeling enriched. However that's not really the point of the podcast. The point of the podcast is to explore new territory intellectually and it may be an academic level outside of traditional channels and it has to do in part with my belief that we don't really understand how much idea suppression has been going on for a very long period of time within the standard institutions. In fact I've I've created this thing I've called the DISC - the distributed ideas suppression complex - and its purpose is to make sure that ideas do not suddenly catch fire and up end and disrupt previous structures. So for example I would claim that String Theory which has absolutely dominated theoretical physics since what 1984
L - yeah since about then
W - so, it's about 35 years. It artificially consolidated the field around a complex of ideas that did not have a huge signal coming from experiment you know to just to try to steal home base
L - I mean to understand that you have to understand the (as I'm sure you do) the the culture of particle physics at the time when string theory started to grow which is you know up until you know up through the 70s there had been steady experimental results coming in from particle accelerators where it was like, a new particle every week that theorists were having to really cooperate on as a community to jump in on try to figure it out and exchange ideas very
W - it was more than 50s and 60s
L - it was but it continued all the way through the 70s and and from that culture of, you know, community working together on information that's coming in a steady stream right, you got this culture of like "yeah no don't go do the other thing it's a waste of time" you really want to be working on what's hot, right? because there's new information coming in all the time and this is where the culture of string theory started I was also more involved in the in the culture of General Relativity and Gravity, okay, which is a very different culture. It's much more slow-paced, you don't have new results coming in all the time everything's very is much more
W - do you mind if I set this up a little bit for our audience and you critique it if I do a poor job (L -sure) in essence the two great idea complexes in fundamental physics - not condensed matter physics or astrophysics - but like whatever ground reality physics *is*, is the General Relativistic complex around the ideas of Einstein and then there's the sort of quantum field theory (QFT) a complex or the Quantum complex around the ideas of Bohr - sort of fair enough? - and Planck and I don't mean to slight Dirac and others but just to keep it simple the children of Einstein and the children of Bohr
L - right and the the the boring people went into particle physics
W - the boring people?
L - well you said they're the children of Bohr's
W - hahaha okay
L - so they're so they're in this culture that's a very rapid fire you know moving moving things along as part of a community whereas general relativity the people from the Einstein community were more exploring different possibilities at their own pace and there is more of an exploratory culture and that's the culture that turned into Loop Quantum Gravity so that
W - so first of all I'm just gonna I'm gonna begin arguing with you there to me yeah the issue was is that Einstein put much more of the general relativistic picture in place, so there was less to do for the descendants of Einstein and because the quantum was considerably less tied up there was much more work and so through a system of selective pressures the more successful community in some sense left fewer descendants and they were less capable because it was less for them to do and then you had the quantum communities start to attract the real brains because there was lots of work for a period of time to go back and forth between theory and experiment
L - that's right
W - okay
L - and and but what happened was that when they when you think about it as a whole - that gravity has to be quantized. So there are two ways of getting there - you can either start from Bohr's children and and quantum field theory and try to get from there to a quantum theory that encompasses gravity or you can start from the gravitational side in geometry and try to somehow get quantum mechanics to play nice with this essentially classical geometric theory and there were two very different approaches and two very different cultures
W - I still have some disagreements but I don't think I necessarily want to to derail us so all right so
L - so anyway my the the point I started with was that the the string theory came out of the particle physics community
W - and when we say string theory, we mean the cultural explosion that happened in 1984 rather than the original string revolution of let's say Veneziano which was much earlier okay
so that in in the mid-1980s there was a discovery called the anomaly cancellation where two very improbable things canceled each other and the theory was suddenly there was a theory that was given a green light that was highly restrictive as to what could... what could go in that spot and that result the anomaly cancellation gave birth to a cultural phenomenon which was the sort of takeover of theoretical physics by string theory
L - right I mean it looks so promising at the time in the 80s I mean they thought that "yes it naturally encompasses gravity" and all we need to do is find the right you know high dimensional manifold to attach to for our strings to vibrate in and will immediately recover all the properties of the particles of the standard model we just have to find the right one we'll probably get this done by lunchtime wrapped up
W - I don't believe that story
L - well it didn't happen
W - I don't think that's a even what actually happened. I was in college during this period and even though that's the story that I would agree is told inside of the community. yeah I'm not sure that I fully believe it if I go back to my own memory is something very different happened
L - well it took a while to get everybody on the bandwagon
W - I think something's still different happened I think that Ed Witten showed up and that there was one human being
L - Right, he's his own anomaly he wasn't
W - he was absolutely an anomaly he came to Penn in I don't know whether it was 83 or 84. I left in 85 and he started talking about what the world was in a way that none of the physicists could actually follow, because he was using ideas from from differential geometry and from higher mathematics in ways that most of the community couldn't track. He was saying things like the reason we have three copies of the kind of matter that makes up our world comes from the characteristic numbers of a six dimensional complex manifold found at every point in space and time and these things were so mind-blowing. I mean if the if our listeners can't exactly follow it they were in the same shoes as many people in the community. There was a voice that was clearly coming from another planet
L - right
W - undoubtedly the most brilliant person I've ever met in my life - the one person who continues to make me tremble when I hear his name or his voice and this person signed on big-time to string theory in a way that was very coercive and seductive so that even though that the community understood why he was signing on, it was in part Witten's endorsement that really started to move the needle in my opinion
L - yeah, and it's stunning just to what degree that failed.
W - Ok, so say more?
L - well the the String Theory unification program - the idea that this description of all fundamental particles and gravity - in our entire universe - would come from a model based on strings vibrating and other higher dimensions. I mean that this unification program has failed. The vast majority of the high-energy physics community has been working on it for over 30 years and they've utterly failed to deliver on that promise despite the high hopes and promises
W - well, and this has to do - and again we can sort of do a small synopsis of the field - the idea was the original hopes had been built around an idealized point particle concept where hard little balls were kind of the naive model of particles then you had to smear them out and do waves on waves from that point particle concept called second quantization or quantum field theory and string theory said no the fundamental unit should never have been a hard little ball to begin with it should have been modelled by something that was an "as if string" obviously and it wasn't string made out of atoms it was some sort of mathematical version of
L - right it's an abstract mathematical description of a surface inside another surface essentially
W - right and so that this this thing had a peculiar appeal to the children of Bohr that was not that appealing to the children of Einstein would that be a fair description of it that
L - it is for pretty subtle reasons specifically anomaly cancellation and also the ability to produce what appeared to be particle excitations within from the string model
W - right now that thing - that sudden shift in the community from regular quantum field theory, from a plurality of different approaches; whether some of them had names like Technicolor or grand unification or supersymmetry all of this seemed to get subsumed in this - I don't know - fad what it was hard to
L - like agiant rolling what kind of Katamari Damacy where it's just collecting everything that it touches and making it part of itself
W - that's right and in fact the claim was if we find something that isn't string theory we'll just find some way of including it and call it string theory
L - right
W - so this was a bizarre you know there was it was a sociological phenomena it was a we would say the political economy of science was involved where who could get a job for their students, whether or not the newspapers were gonna challenge this or go along with it. So you had reporters who had no idea what was going on publishing these glowing pieces about the string theorists and how they were gonna wrap it all up (L -yeah) and in essence you know we have this concept in evolutionary theory called interference competition where one animal will attempt to out-compete the other by keeping it away from like a watering hole.
So nobody else could afford to get nourished because the string theorists we're saying all the smart people are in string theory, "it's the only game" in town was the famous phrase
L - I certainly encountered a lack of nourishment when I graduated in the 90s and I wasn't interested in strings but I was interested in high energy physics
W - well I think almost everybody was in that position that that is really the founding crime for me in the string revolution. It was the desire to say that everyone who is not part of us as an idiot
L - yeah yeah. That's above and beyond normal physicist arrogance
W - above and beyond normal physicist arrogance and I want to say also why I think I'm so focused on theoretical physics as the most important endeavor that humans are engaged with I think there are three components to it and just see whether whether it resonates with you
1) one is that this is the closest we get, responsibly, to asking why are we here what is it that we're made of. It is the thing that would best substitute for a religion if you were able to understand what it was.
2) the second thing is is that it appears to be the secret powering our economy that very few people have really fully understood. It gave us the World Wide Web the semiconductor the electron shells the generated chemistry, (L - nuclear power), nuclear power, nuclear weapons, communications technology - electromagnetic, you know, Wi-Fi what have you. If you want, and invented - theoretical physics - more or less created molecular biology.
L - that's probably a bit of a stretch but the other certainly aren't so yeah
W - if you look at the RNA Tie Club, you know the people and it word Teller Feynman, Crick, people trained in physics, so in this telling of the tale its second major feature of importance is that it sort of created our modern economy and I don't think people have understood the extent to which all of these things for you know - the web, semiconductors and even molecular biology - really came out of theoretical physics because of the third issue which is I think, even though I'm a mathematician or trained in mathematics, I could make a pretty decent argument that
3) this was the world's most impressive intellectual community ever
L - it certainly it seems to attract some of the greatest minds
W - well I would say I would go even farther I would say that because of the interplay between the most beautiful mathematics even according to mathematical standards and experimental discipline. So you have this this thing that's forcing you to go back and forth between the purest of pure theory and the the dirt and intuition and messiness of experiment I don't think anything else had that property so that it wasn't necessarily even that it just attracted the best people, but it it actually rewarded human intellectual achievement like no other subject ever.
L - all right it's also on touching on something that's a little bit different socially which is the type of people who are attracted to really, you know, hard problems in fundamental physics and and modeling and really trying to get as you say the source code of the universe. These often aren't very skilled "people people", they're not very socially oriented people for the most part
W - some are some aren't yeah
L - but for for the real intellectual heavy-hitters you're talking about people who sort of I mean walk among us as aliens you're talking about think that they're not extremely social they're not very focused on issues with other human beings and physics - this understanding of our universe through mathematics is really otherworldly pursuit, right? it's not like law where laws are made up by humans and discussed in front of humans compat in front of humans it's I mean that has its own intricacies and difficulties and puzzles but theoretical physics you're getting you're working at something that's not related to humans directly.
I mean any intelligent beings in this universe that advanced to a certain state are gonna be involved in studying physics and it's gonna be the same physics, right? with some of the same mathematics and the same mathematical tools. It's something that exists independent of humanity so if you're if you're not a huge fan of human beings and but you you really like puzzles and you're good at math, physics is very attractive because it's a it's a it's the greatest puzzle there is in our universe and it exists completely independent of humanity and yet humans have be able to work on it and make progress which is frickin amazing.
It's amazing the degree to which humans have understood our reality and and I think we're getting close to having a complete picture of it
W - yeah, I would say that's one of the three classes of greatest puzzles. I mean if I could I could tell a story that biology is the greatest puzzle because without something to care about the universe in which it lives this is all completely sterile to begin with
and I can also make a different case for mathematics which is that physics is but one example of a universe we don't know if there are other universes that can could be (conceived)
L - so so biology I mean it's it's I I agree it's intricate and and it can be a pure pursuit but it's not pure in the sense that so much of the foundations of biology are somewhat arbitrary like whether it you know DNA a helix is gonna spiral to the left or the right and and and what its chemical components are precisely that might vary other planets you know other civilizations' biologies could be different
W - (you can) make a decent argument that systems of selective pressures as described by Darwin and Wallace might be conserved even if you had didn't have carbon based life
L - there will be convergent evolution of course sure but but the details will be slightly different so if you're studying biology by the time you get up to something like cells or animals it's gonna be wildly different in different different places in the in the galaxy alright whereas whereas physics is the same everywhere okay it's it's independent of biology and it's independent of humanity and it's I think and then when you go to mathematics mathematics the pursuit of mathematics like how things get proved and how structures get built up through axioms that are then proved it's a it's a larger playing field than physics. So within that huge arena of possible mathematical structures okay we see appear to live in one mathematical structure, so I mean a physicist only has to focus on the the mathematics that we that describes reality
W - and I by the way share your intuition then in a certain sense this is the best and most interesting place to play in part because there's this very weird feature that we've seemingly unearthed about the physical universe which is that it unexpectedly has this bizarrely good taste (L - yeah) about what to care about within it's as if you let it loose in the mathematical jewelry store in it it selects only the finest pieces
L - yeah yeah and we have to wonder if that's you know is that just our human take on it because our human aesthetics have evolved within this beautiful world in the universe so, is it that I mean Douglas Adams described the anthropic principle as a puddle of water right and thinking it's like wow this "this this hole I'm in is just perfectly formed to my shape alright isn't it wonderful how it just fits me so perfectly and it's so comfortable here just like it was made for me". Well, it's like, no the puddle got there and filled the shape of the the hole I mean the water got there and filled that shape and as humans we ended up here and we filled this niche and our aesthetic taste was shaped by what's around us including the the mathematics that underlies the physics of this universe and so when we look at the universe you might say "oh no maybe it's just our tastes evolved within this universe, so this is why we find physics aesthetically pleasing"
W - do you actually believe what you're saying right now
L - no I think it's wrong
W - I mean I think this is so cowardly
L - I know I agree and that and right like I have to wonder about it I have to I mean I understand (W - we have to pay lip service) you know that's not just lip service I think about this I mean I think I mean is it really my proclivities have been shaped by my environment in order to think this because I have to question everything all the time (W -sure) mostly cuz I don't talk to enough other people but but also it's because you know yeah when you're questioning things and you're delving with fundamental building blocks you want to make sure as you build things up that you have things right and in looking at the fundamental pieces of physics you know the fundamental mathematical physics I really think that the mathematical pieces as you say are the ones that are extraordinarily beautiful and it's not just my aesthetic taste has been shaped by evolution that causes me to think that I really think objectively these are very pretty mathematical objects underlying our physical reality
W - yeah I think we just lack the courage to say what this appears to be which is there is something that we do not understand about the universe in which it is selected for the most mysterious, most beautiful stuff with which to write what we - I mean - with the closest thing we have to source code we don't we're not at the source code yet we're not quite at that layer
L - but you can smell it can't you
W - well I mean yes and no
L - it feels close
W - I think it's almost provably close but but the there's a caveat to that which is I think we're almost at the end of this chapter and it does feel like it could easily be the final chapter and by the way we should be we should clarify that when we see when we talk about a theory of everything we don't mean a theory that once understood could explain everything you see in your daily universe
L - right I mean love is still gonna be a mystery of course
W - oh god you really did that
L - of course I did but yeah nobody's...
W - Ladies form a single-file line
L - ...there's evidence I mean there in our in our understanding of physics as we've learned more particles yeah the fundamental particles we've learned about appear to be filling out a complete set. I mean we've, you know, when you when you predict that a Tau quark should exist all right know that a Tau Lepton should exist, yeah, or you figure out that you know it completes this set, there's this third generation - it's complete right so we seem to be completing our set a fundamental particles
W - SO we have three sets of Lego yeah right the first generation, second generation and third generation of matter and all the pieces in each generation are mirrored in the other two generations just at different mass scales. So far that's what it looks like
L - well it's not just so far it's like whether we have we have reasons to know that there aren't there aren't more from from how the Big Bang sent matter loose in the universe, we know that there aren't more than three generations up to a certain very high energy
W - well we've known a lot of things Garrett that have turned out to be wrong
L - well but this is really filling out a pretty complete pattern
W - I don't dispute but I just
L - except for this minor point of dark matter still being completely unknown for the most part
W - yeah I mean I guess my discomfort with this comes from the fact that knowing the history, I know how we've been wronged and I also know how we haven't had the courage of our convictions and one of the things that really you know occupies my mind is why we're not more definite about things that I think we have very good good reason to believe and we're so definite about things that sort of scare me where we say I know that it can't be other than this and yet it has we've been we've been shown up multiple times that we've got two different directives telling us to be both more confident and more humble
L - right
W - the thing that has affected both both you and myself most profoundly is the existence of something called spinors at the core of our understanding of matter do you want to say a little bit about what that is Wyatt you think it's affected you and and and me as well and why perhaps it hasn't had the same emotional and intellectual impact on the community
L - right I mean when you're... basically when physicists more or less completed that what's called the standard model of particle physics, right, you have you have the the known forces in physics like the electromagnetic force, the weak force and the strong force as well as the force of gravity and then you have the the matter particles which are electrons and quarks and neutrinos and and other generations of these that form you know what are called the fermions okay and these are called the matter particles and then they have mass because of the interaction with the Higgs boson right which is sort of...
W - that's not going to make sense to people
L - it's not alright but anyway the the force particles behave differently as elementary particles under rotations than the matter particles all right. so these matter particles, they you have to basically rotate them 720 degrees to return them to their original state. Whereas most objects you rotate it and you rotate it 360 degrees and get back to where you started all right but spinors are different right and they they behave in a very specific way and there's a there's a very specific way of describing them mathematically but it's described in an unusual way. It's described as a as a column of complex numbers or a column matrix if you like that's acted on by a rotation matrix that tells you specifically how these particles transform under rotation
W - honestly that wouldn't make any sense to me and I don't think I can help all of my audience together
L - this is the thing so so this is the way physicists are introduced to a description of electrons
W - well look I just try to play with something well we're talking about this is this way..
L - well you can, can I hand it off to you in about 10 seconds?
W - no you finish it out
L - all right so I found this description to be incredibly unsatisfying all right because the rest of physics is not described this way right you don't introduce a fundamental field that transforms a certain way under rotations.That's not how you know why would the universe do that it's not elegant it's not it's not geometric all right it seems sort of arbitrary, why would the universe have spinors in it? well it turns out that because if you if you describe General relativity as curving four-dimensional space-time describe gravity and you just describe forces as gauge fields right with both of those they're very geometric descriptions they're very elegant mathematically when you describe, physically, the fermions as spinors, it looks like a kludge it just it doesn't fit with the other theories but that's why I left physics, to solve this problem I wanted to know "why spinors geometrically?" and no one else was interested in the problem no one else thought it was a problem they're like yeah they transform this way and and maybe it comes from strings and that's all you get and it's like no that's totally unsatisfying.
If gravity is described geometrically and are all our other forces described geometrically the universe is just one thing it's right there in the name I mean "uni" is one, "verse" is turning we have we have this "one-turning thing" we call the universe and it's just one mathematical object and if this if we have different particles they have to be aspects of this one mathematical object why would this mathematical object have spinors as an aspect of them it was a huge mystery to me I want to go solve it no one else even acknowledged it was a problem and you also tackled this this also bothered you
W - well there was a so this is the very difficult part of what the portal is supposed to be and I have the feeling that we've probably left a lot of our listeners behind but I've said that we're going to have to take some risks and this is going to be one of them, so the way I see it some some of our listeners are also viewers right and we have in studio these beautiful Klein bottles from Acme Klein Bottle and Cliff Stoll out of Oakland I guess these objects that I'm holding up or you can look up Klein bottles on the on the web have this very odd property that they are covered if you will by the surface of a doughnut if the surface of the doughnut wraps around this object twice and we call this a double cover. Now the idea that you have some very strange object with no inside and outside called a Klein bottle but that it's wrapped twice by some object which has different properties namely the surface of a doughnut called a torus, the rotations of our three-dimensional space, bizarrely have some object that covers them twice, just as a doughnut covers a Klein model twice so when we talk this crazy language about you have to rotate an object more than 360 degrees for it to come back to itself, this is somewhat of garbage language that we've taught people to understand, when we're not really showing them what's behind the curtain.
We're not showing them that there are the rotations of a rigid three-dimensional space and then there's this thing that covers those rotations twice called the spin group and that spin group is the thing that has the property that it acts on these things called spinors so this is a hidden level of structure that you would not know was there just from three-dimensional space there's some secret trapped in three-dimensional space that is very well hidden, and if we weren't at a very high level of mathematics or physics you would never know that spinors even exist to play with
L - right I mean it comes out of representation theory but that once again that's a fairly high level of mathematics you have to get to to even see that these things exist
W - and for all of the other basic kinds of symmetries we don't have these hidden representations we don't have these hidden spaces that have these bizarre properties it's only for these things called orthogonal groups so it's a very special property of real Euclidean rigid space that spinors are there to be found and not only does nature find them, she bases all of matter around the hidden object that can't easily be seen or deduced which is a total mind job right? and the math community has in fact sort of split between people who think hey we can describe these things mathematically so our work is done versus other people who believe there's something about spinors that just it continues to surprise us we don't understand where they came from there a hidden feature of the universe and they keep giving in this very mysterious fashion
L - yeah and the most of the general relativists who came at this problem um just would not want to touch it because it's too far into them and the people came into it from the particle physics side thought it wasn't a problem - it's this field transforms a certain way it seems perfectly well described
W - that doesn't this doesn't make sense to me at all
L - so it didn't make sense to me either, Eric...
W - Let me give an argument as to why this is a real really serious problem. If I take two kinds of thing that might one might hope to find in the Universe an electron and a photon okay? so the idea is that I've got stuff that orbits around atomic nuclei (electrons) and I've got light and it's relatives that carry the electromagnetic force in the photon. If I don't know how to measure length and angle I can still talk about the objects that are photons, we call them spin one particles, but if I don't have length and angle I don't have any way of talking about spinors.
In other words, if there isn't a ruler and a protractor, which is effectively what Einstein used to define space-time I don't have an ability to talk about spinors and that's a big problem because if you're...
L - It's not just a problem, it's a huge clue it says the spinors have to be intimately related to gravity and general relativity
W - and gravity so spinors are over on the quantum side of the equation all right the quanta in the children of Bohr it's really more their object than the children of Einsteins. The children of Bohr claim "we have to quantize gravity and make everything quantum" so it's sort of an imperial belief that the people who study the standard model should extend their techniques to cover gravity so that all can be won yet if it turns out that they're we don't know how to measure length and angle between measurements because in quantum theory you get something very different when when things when a field is propagating versus when it's measured - all of the probabilistic stuff we talk about is happening when there's a quantum measurement. If you don't know where length and angle are while something is propagating then you don't even know where where the electrons can be a disturbance if electrons are waves they have to be waves in some kind of a sea.
You know with photons that you can't tell exactly where the wave is but you know where the sea is
In the case of electrons if you don't know where the the metric is, you can't even say where the sea is that the electron would be a wave in (L - that's right) and it's a very convoluted thing but it's a big difference
L - yeah and it's I mean I can almost describe it in extremely simple terms which is, most people most physicists who think about it, think of gravitational charge as being mass but gravitational charge is really spin
W - well you we're getting pretty we're getting pretty far afield
L - all right so to speak :)
W - so to speak so let's imagine that maybe our listeners haven't understood exactly what we're saying but that there is some special problem about spinors and how they're tied to the structure of space-time that is different where you can describe things like photons in some sense without knowing how length and angle are measured, whereas length and angle are essential if you're ever going to talk about spinors.
Now you and I have two very different points of view and the reason that that I consider you an arch-nemesis is that I think your theory based on e8
Which is depicted in this crystal block for those who are viewing on YouTube (NOTE: Probably looks something like this) L - Thanks for bringing your Kryptonite to the show
W - your approach to this is to say let's start out with some object that is mathematically distinguished and very peculiar effectively like a platypus of the mathematical world and let's try to distill from this thing that has to exist for reasons of logical necessity and may be the most complicated naturally occurring object, arguably, that you could pick and let's find the richness of our natural world as distilled from this bizarre, freakish occurrence in the laws of mathematical necessity is that a fair telling?
L - um from a top-down perspective it is but the way I got there is by describing spinors and seeing that spinors is part of this one beautiful mathematical object naturally and it's it's unique to the exceptional Lie groups to to these this class the small class of objects
W - when you say exceptionally groups what you mean is (L - platypi) continuous symmetries that only occur once that they don't fall into some regular pattern
L - and spinors are naturally a part of their geometry and there and there and there their intricate beautiful objects they have spinors naturally as part of their geometry and that if you dissect them you can see all the other parts necessary to particle physics and gravity and this was just stunning to me and at this point I'm like alright I've built up from the ground up from from particle physics and from gravity and from spinors. I've built the structure up in seeing how it's all interconnected and I found that they're all part of this small class of mathematical objects that are that are unique in their intricacy and beauty for finite dimensional objects and that's why now I appear to have adopted more of a top-down view where it seems like oh I started with this pretty object I said oh look it explains everything but it's it's nowhere near like that how I actually got to there all right.
The truth is I'm building up and the truth is the next object is going to be higher dimensional objects that include E8 like this one as a subgroup
W - so the way I'm hearing you Garrett and, again, you know this is like one of the most obscure
L - this is going to lose so many of your listeners, but I'm happy to talk I
W - Well, I'm trying to, we're trying to describe this. I would like to describe this a little bit as as if we were taking somebody to an opera in a foreign language so that they can follow the plot even though they can't follow line by line, OK?
The way I see what you're saying is is that there is a usual kind of symmetry which we would associate with bosons that is the force particles of the universe and what makes these very strange objects that you've you've referred to as in referring to exceptional lie groups is that you appear to take something from the fermionic universe that is this spinorial universe where the spinors come from and you adjoin it in some sense to the bosonic to get more symmetries
L - yes yeah that's very clear
W - okay there's a huge problem with the strategy
L - we'll wait but this but you're forgetting the part where this structure exists as part of these exceptional objects
W - I'm not. You've correctly described how these objects occur in nature that there is some regular kind of typical symmetry, a bosonic symmetry then you you take some of these spinors that are related to that symmetry and you fuse them together to get an even more beautiful, weird, symmetric object but the problem with that strategy is is that we know that nature has these two very different recipes for how she wants to treat these things quantum mechanically
L - right
L - anti commuting numbers. number were A times B times equals negative B times A
W - a parallel totally different treatment and the way you've done it you've really taken the fermions that is the matter part the the spinors that we've been discussing you've lumped them together with the bosons and now they're fused in a way that it's going to be almost impossible to treat the spinors in a manner befitting fermionic quantization
L - yeah no, it's very straightforward though the the fermions just end up being along directions orthogonal to space-time
W - I don't see that that actually works. I mean this is my great... my criticisms of your theory which - we've known each other now for 11 years and this is the basis of our antagonism - is that on the one hand you ingeniously saw, and give you your credit, that he E8 the largest of these objects, a 248 dimensional behemoth, carried some numerology surrounding three copies of The spinors that are present, which looked like, in some sense could be confused for, maybe related, to three copies of matter.
L - it was about that hand-wavy yeah
W - okay so, all the honor to you. That's not an obvious feature. Most people who barely know what the exceptional lie groups are and most of them don't know that it has to do with this property called triality
!!Eric's Objections to Garrett's Theory
1) okay that was... that was true but there really wasn't, in my opinion, enough room to pack the particles that we currently see into this group structure with three generations. That was one issue
2) Second of all because of the unit of the particular way in which bosons and fermions, matter and force, were fused together it really pushed everything towards the bosonic side; that is the force side of the equation, so you're gonna now have to be in some kind of technical debt where you would have to figure out how to get the fermions back into a matter framework because you would actually push them too far, through unification, into a union with force. That was another basic concern and..
3) my last concern was that because of the properties of this object you didn't have any room for what we call chirality in which the universe that we've seen so far appears to have a left-right asymmetry to it - it's as if it has a beauty mark - and any object that you derive from E8 is gonna be very hard to get it to have a beauty mark because E8 doesn't have a beauty mark itself, so these were three things that you're going to have to pay back (L - right) if you were going to connect this to the world that we see and that might - my irritation with you was that I brought this up with you in 200? remind me? 2008, not 2009, when we met at the Perimeter Institute and I tried to warn you about these things I felt like you never took me seriously.
L - No, I did take you seriously. I've taken all these problems seriously and they're discussed in subsequent work and the way I've been resolving them is by tackling a larger, unspoken problem which is how to have a quantum description of this sort of geometry, right?
Because our universe is a quantum universe and E8 tis a finite dimensional object and you have to have multiple states, multiple numbers of particles be able to occupy every state so if you have a full quantum description of a theory you need an infinite dimensional geometry to do it.
W - well I always thought your your goal was to take a finite object and then take waves on that finite object to create something that was going to be infinite dimensional I didn't see that it's a problem
L - but that's not good enough
W - say more
L - because when you talk about waves on geometric object those act as different representations mathematically, the Peter-Weyl Theorem, but when you when you do that that's not enough to give you all the structure you need for quantum field theory (QFT) you really need a fundamentally infinite dimensional geometric object to describe quantum field theory and by looking at what sort of objects you need, that include exceptional lie groups, but are infinite dimensional geometries that can correspond to quantum field theory - that's how you tackle the three problems you discussed...
You can have more space to handle the three generations of particles, you can have the anti-commuting fermions in them so that they behave like from yan should like matter particles should and it's also you know large enough to give you the sort of dynamics you need for quantum field theory. So that's why I've I've in the intervening ten years since we've had a deep discussion about this, I've now started looking at generalized infinite dimensional geometries which are infinite dimensional generalizations of Lie groups which at which solve these problems and that's that's why I've been...
W - You really believe that you've solved these problems?
L - I think I have a really good description that goes a long way
W - Garrett, here's the thing: if I just think about where we are with the standard model right you've got four dimensions of space and time, right, then you've got an extra eight dimensions coming from something called su(3), three dimensions from something called su(2) and one extra dimension coming from something called u(1). That's the basic data (L - right) that occurs.
L - and gravity, people leave out gravity
W - you can put in six dimensions for something called spin(3 1) okay but the point is I can add those all up and I'm gonna get some number probably, you know, in 20 some odd dimensions whatever that finite thing generates the infinite dimensional world of quantum field theory
L - but wait a minute. Quantum Field Theory - there we have a way of mapping between those the base geometry and then going to quantum field theory right then you have Fock Space right and you have occupation numbers for all the different possible States
!!(Some of) Eric's Objections to String Theory W - do it my point is you're working on a problem that has certain foreseeable problems as part of the challenge and unlike your detractors from the more standard community I'm not I'm not telling you that you're dead on arrival just because certain problems can be seen. That would be unfair and then by the way that's what you know there's lots of problems that can be seen from the string theory community where let's say
- you know the the number of dimensions it wants to play and it doesn't seem to be the right number or
- that they thought there were only a finite number of theories it turns out that there's a continuum of theories or
- the vast majority come out with right and I get very irritated that somehow the string theory community is entitled to make all these mistakes and anybody outside if they say one wrong thing or one seemingly wrong thing they're excommunicated it's a ridiculous standard okay that's not what I'm trying to do to you I'm trying to say something very different which is you're going to be up against the fact that if your initial data comes from this most beautiful and most bizarre of all objects E8 and that doesn't contain
L - as I said I'm now work it's generalizations to infinite dimensions but there's an issue of intellectual check-kiting like I don't mind the idea that you recognize the debts that you're in and then you say I think I have a way of getting this thing to close off (L -right) but there is a question of well now that you've recognized am i right I mean am i right yeah yeah right i right that the issues that I raised with you initially turned out to be really serious problem
L - of course I mean and you
W - but you didn't know that then
L - I did they were there in the paper there in the original paper saying that the the description of three generations was very hand wavy and unsatisfactory that's in the original paper
okay my recollection was that when I tried to explain to you why people were going to have the objection about the two different quantization schemes that that was not handled correctly
right I handled that in a paper in 2010 or so (in ...group? cosmology)
okay so that all right that was one of the the issue yeah then there's gonna be an issue that you weren't able to bring the left-right asymmetry out of the initial data there wasn't enough and that was a fair description
absolutely okay and then you're saying that the I ceded to you that you were making a connection between the mysterious appearance of three copies of matter and something called triality which was not manifest obviously inside of E8 but to the few people who actually care about this structure it it definitely is there in a very profound way it relates to rotations in 8 dimensional spaces yes but you also haven't taken an interest in what is E8 if not the the wellspring for the source code of the universe like if it isn't the universe I think it's a piece of it but I'm not religious Eric I mean I'm I'm gonna explore whatever seems most promising to explore okay and well have you changed your your sense of the status of E8 tis a candidate for the unified theory in the fashion that you were originally seeing absolutely you have changed your yes can you talk about that right so it was in tackling quantum field theory and how to describe it geometrically which as far as I know nobody has done I mean whenever whenever you start with as you say you want an su 2 su 3 and you go through this quantization procedure for its field so you don't filter or if you're dealing with strings right you have this model of vibrating strings and higher dimensions then you go through this quantization procedure to get a quantum theory of strings (W - okay) right we have we physicists have this toolkit for quantizing things but that's utterly the wrong way to look at reality if if the universe is just one thing which it is then it's one mathematical object I mean you're making a point that is very well understood I believe in the right standard theoretical physics community which is that if the world starts off as quantum (L - right) you should talk about classical izing pieces of it rather than quantizing the classical pieces that appear to exist L - yeah that's exactly right so so what's a quantum geometric object look like it's in you know with with all these infinite dimensional Fox space and the creation and annihilation of elementary particles people possible people at home won't know what a fox bases box space is effectively where the states of the system can live when you have multiple particles in a situation and you can change the number of particles that you have just the way a photon can break into an electron and a positron pair that would be possible in a fock Space not possible in a simpler quantum so (that's right) so effectively a fox base is just a large place to play where the number of particles in the system can change up to infinity (W - keep going) so in order to describe this as one geometric object you're stuck with a generalized Li group infinite dimensional generalize Li group (W - yes) and in order to describe spinors it's going to be an exceptional generalize Li group yeah
W - I don't think I don't think you're adding anything I think that the problem here is is that E8 is an exceptionally beautiful, exceptionally interesting object. It did have the properties that you were talking about in that it unifies standard symmetries with these spinors to form new symmetries that's right
But it's inadequate it's not only inadequate, it would push them into a universe of pure force rather than a universe divided between force and matter you're actually the problem is is the kind of unification it would create would be completely force unification with an absence of metod you'd be dragging matter if you will spinor W - you're focusing on a problem that that that was you know they're solved in a paper in 2010 but it's very simply that fermions are orthogonal to space-time whereas you know the force fields of boson fields are along space-time. In the same way the the same way if you have to force fields that are along space-time but in different directions they would anti commute right so you're doing is you're using space-time if you will which is again kind of a classical Einsteinian concept to break apart a unified system which was the intention in unification to begin with and then you're going to try to treat these two things naturally according to two totally different prescriptions that's like you're violating I mean in some sense any kind of naturality that you just picked up in the unification to begin with L - um in a sense yeah but the symmetry has to break somehow W - does it do it and in natural I mean this doesn't feel this feels we know L - it allows it it doesn't seem completely natural but it does allow it W - well but the whole point of the thing I thought was to take the naturality and what we had understood about the nature of these exceptional objects and to say hey these things actually unify beautifully inside of these very unusual elegant mathematical structures L - they do but it was it was too small as you said it was too small because it didn't correctly contain three generations of matter and because it can't correctly portray quantum field theory but once you go to the larger generalised Lie groups it can W - well you know if this was a start-up what you're saying is that the business is going great but it's just run out of money and I needed a fresh injection of cash... ...it does! This is sounding like intellectual check its round be funding Series B I see, err, is it cash flow positive not yet I haven't even put the paper out yet W - okay so the there's I mean I look it's not a question that I I need to see the paper or that you're not allowed to take out more loans but are you getting more I mean I know you to be look I've. I hate to say this but I have defended you to the regular community with some frequency because I have viewed you as an honest broker for your own stuff. I don't think you're trying to get away with something I think (L -thank you) what you try it what you're trying to do is you're trying to say I need to take some advances which I think and I hope I can pay back which i think is an admirable and honorable way to do physics. Are you worried about your own theory? are you worried that you're going to infinite dimensions in the way that you've been forced to modify on several previous occasions and that in fact this is not going to close ? L - I am unusually confident that I'm on the right track with this one W - really... Oy L - there are too many things matching up in the right way W - this doesn't sound good Garrett I gotta be honest with you L - but it's see I will put a paper out yeah yeah okay and you know people may not find it interesting or they might find it really interesting W - well I wish you the best of luck but I have to tell you that I do think that the problems in this program.. I mean again I should just be honest about it... I thought that the choice of E8 was so natural that there really one of two choices that I can see is being the way to go if you're going to avoid the the usual paths in research into into fundamental physics. One is that you start with the most beautiful intricate object you can find and then you find the intricacies of the natural world somehow living inside of the intricacies which occurred naturally. L - that would be that's a top-down view and it's quite nice to look at that W - the bottom-up view is that somehow you start with something that's practically lifeless which I've analogize to a fertilized egg and somehow it bootstraps itself into this weird intricate and baroque world that we find ourselves in and it sort of... the universe Auto catalyzes from almost nothing and these are the two basic approaches that I can imagine that would not strain the concept of a theory of everything L - right well then we both engage in both of these. Once you've used this bottom-up approach right starting with your fertilized egg and getting up into more and more complexity, then you start to see a complete object after you've expanded it out W - sorry you view yourself as exploring the concept of L - going from the bottom up W - what is it that you've done that that has that character L - starting from gravity and particle physics and how they can be matched up together and in a in a way that brings about natural W - okay that's that's not very simple at all well I know rabbity gravity is already you know you're talking about the curvature of a space-time manifold L - that's beautiful stuff that I love it W - no it's absolutely gorgeous I don't think we're divided by that but when it comes to you know breaking up this object called the curvature tensor into three different pieces throwing one of the one of them away called the Weyl curvature and then fine-tuning the other two to be equal to the matter and energy in the universe there's a lot of stuff that's going into that story that isn't and that's an intricate story and then the other story is even worse and (L - right) here der yeah so you know you're smuggling in a ton of complexity when I say fertilized egg I'm thinking at the level of cytology but you know at the level of the actual DNA that's incredibly rich so you when I you know maybe it's a bad analogy because it's not bootstrapping itself out of nothing (L - right) you're smuggling in a ton of intricacy L - but you have to look in both directions you have to look from the bottom up and then once you can see the larger picture then you have to look again from the top down and if going that way from the top down doesn't match up very well with with what you did to get there then you have to go further and so you can get a different bigger picture it's the only way forward W - Garrett but I'm gonna be honest I feel like you know this is something is run into a wall and there's the sense that like how could this beautiful structure not be not be right it doesn't feel to me like... L - it's insufficient yeah yeah and there but there there's there larger structures that are not finite dimensional but there's still Lee groups and exceptional Lee groups they're just generalized infinite dimensional Lee groups that contain E* a substructure and they're beautiful they're just as beautiful if not more so W - I really don't I think that the problem is is that you know we have this mutual friend Sabine Hossenfelder when Sabine has this very strange feature of her personality that she needs to tell the truth at scale L - well sabina is a scientist and scientists you know engage in the truth at all costs yes but serve our modus operandi W - well I find it very interesting that almost no one has followed Sabine's lead L - I think it's a bina Sabina yeah (NOTE: it's not) W - okay from her perspective Beauty has led theoretical physics astray (L - right) now I've I've tangled with her. My claim is is that the the string theory community which has generally hoovered up the most brilliant minds but turned them into kind of almost cult-like members which are exploring some structure but I just don't it's it's similar to e8 in the sense that I'm not positive that it's the structure of our world. It has some beauty and some consistency but I'm not positive that that's its reason for being and because that argument has been so abusive and it's it's just been... it's been abused against other people that our work is beautiful then when those Outsiders look at it doesn't look like what you're doing is that beautiful at all. She's gone against beauty as a means of trying to figure out what's true and what what isn't. I'm concerned that you're falling prey to the siren of beauty where you're not coupling you're not... things that are beautiful that there are many things that are beautiful that don't exist to do what you think they're there to do L - right well that's definitely true. I'm definitely inspired by beautiful mathematical objects. When I start exploring an area of mathematics and I start to see its intricacies and it's connection to fundamental physics I am led to think that there might be something there based on aesthetics W - well and I and I've also discussed this with sabina (sabine) who i think is great in her points are wonderful but i would be lost if I didn't have this aesthetic sense as a guide L - well let's take an example like the hydrogen atom so you've got one proton at the center of a hydrogen atom and you have all of the electron shells in quantum theory that are generated by the Coulomb potential that comes off of that nucleus right okay. That story of chemistry as just being these perfectly spherical electron shells works pretty well well you've got the other orbitals - p orbitals, s orbitals, d orbital orbiting over all these things W - yeah yeah in terms of the representation theory of something we'd call spin 3 that gives the symmetries of the system that story is not it is absolutely beautiful and it works pretty darn well but it starts to fall apart the larger the atoms are and the more neutrons and protons are stuck together in the in the nucleus L - it gets much more subtle yeah W - well it's it's a perfectly beautiful story that isn't the right story it's not the true story it's very close to a true story it's suggestive it's indicative but it isn't actually the true story itself so you have to be very careful in my mind that you you don't fall into the trap of thinking that the hydrogen atom sort of generalizes it's perfection is simply the story of chemistry L - right of course they're much more complex elements and then grouped into molecules and there's all sorts of things that go into that sort of chemistry W - well but you don't you have the same situation in theoretical physics where you have certain kinds of beauty that are incredibly pure that actually kind of fall apart under scrutiny and you have other kinds of beauty that seemed to fall apart but actually go the distance. I'm thinking about Dirac's discovery of antimatter is the corresponding solutions to the matter solution L - Right, and then he originally think that was that the anti electrons were that were actually protons W - because they only knew of those two particles and then Heisenberg tried to pop his bubble and said you know L - you actually have a new particle here W - well no he said that the proton was way too heavy to be the anti particle mirror of the electron and I think direct sort of recanted but Dirac should have had the courage of his convictions and said I predict that there will be two new particles an antiproton and an anti Terron which was called the positron and both of those things turned out to be true L - yeah and that's considered a victory for the aesthetic of beauty in mathematical physics W - yes but there was an intermediate there what situation in which the beauty led Dirac astray because he wanted to shoehorn his theory into the pre-existing world that was understood L - that's right so it's important to be cautious but and careful (W - yeah) but not too cautious so if you're if the mathematics is actually telling you something you want to listen to it W - what's the mathematics telling you L - it's telling me that I think I've got the first handle on a geometric description of quantum field theory
01:18 = W - Garrett, I say this out of love and I hope not Envy I'm super concerned that you can see the problems from here and that rather than just going to infinite dimensions and saying that quantum field theory requires a jump from finite to infinite dimensions you can say look I I am fighting the fact that the the beautiful unification that I found actually is going to be challenged at the quantum level where that beauty becomes my enemy L - I would never put it that way W - I know because what you did is you took a theory I mean, to be honest, there's a different set of objects called the exceptional isomorphisms which aren't the exceptional lie groups that have the exact same property that you found where you take something from the force universe let's say there's some object called spin(6) which by an exceptional isomorphism is equivalent to some other object, surprisingly, called su(4) and you can take the spinors of spin six and find out that they are just the four dimensional object from su(4) right and smush them together and you get an analogue of E8 (L - yeah) there's also probably not used by the physical universe in any way that we think of as being important I don't think that that feature is what you think it is L - right but there world of mathematical possibilities out here and I think we need more people
W - I totally agree with you that we need more people fanning out and trying things that look like they won't work
L - so we need a more exploratory culture
W - we need a more exploratory culture and we need to be forgiving what we don't need to do is to fool ourselves when we start getting the sense that maybe this stuff doesn't actually work I mean I it just like it feels to me like I can sort of see what the next set of problems are gonna be and it would be I would be remiss if I didn't say them at the beginning
L - sure but you know you can't really dig into this stuff until you see the mathematical details of it
W - and this gets back to an issue of the question of how science should be organized. So we've talked about how difficult it is to do science inside of the institutions because there is such a pressure economically to do whatever's fashionable to get lots of results, to publish continuously; can we talk a little bit about what happens when we try to do science outside of the institutions. Both of us have and I think people will be very surprised to hear it been rather critical of how hard it is to do science when you're not part of the standard community
L - right I mean I think in some sense it is essential to say to stay connected with the scientific community even when you're exploring out almost entirely on your own you one thing that has to happen is you have to have an extreme set of internal checks on your own progress and because it science is extremely frustrating to work on most of the pathways you follow end up being dead ends and it can be really frustrating. So in doing that, if you're gonna work outside academia you also need a extremely strong support system and a healthy life independent of the science you're working on. So you need to have good support from friends and family, good relationships. You need to have confidence and your ability to support yourself and and that frees up your time if you're really gonna work on stuff outside of academia on your own. I've been fortunate enough to build into and to have those things. I feel really lucky to be able to do that and I think I've had a really good life that way but if you can do that, you need to be really careful about it Because if you if you if you just abandon everything else because you have this idea in science that you want to pursue and you abandon everything else you'll be totally out of balance in your life and if you hit some frustrating item and what you're researching, it'll be crushing because the main thing you're working on focused on stop working when really what you wanna be able to do is, like, oh I've got other stuff going on that's keeping me happy this thing didn't work out I just have to wipe the board clean and start fresh and that's not devastating to do because the rest of your life is good. You have to do that otherwise you just won't be healthy as a human being
W - okay and you have created something that you think might be an intermediate between being in total isolation and being hooked up to the community that lives within it's it the standard institutional structures
L - right that's right I mean I have I came to this idea when I was wandering from friend's house to friend's house after getting my PhD I would basically go hang out with a friend I haven't seen in a while and if it had extra space I'd spend time in their house while I worked on theoretical physics and enjoyed the local environment and I thought was great to be able to do this cuz you're not worried about you know having a roof over your head, you have company to interact with and you have a good environment to play in. I wanted to have a network of such places but I had a hard time getting friends to give me other houses to use for this so I ended up getting the resources together to buy a house in Maui and and to start bringing friends and visiting scientists in. And I've called this the Pacific Science Institute and currently it's basically my house with delusions of grandeur because what I also have is is a beautiful piece of property that's 15 acres that I bought 10 years ago because I like doing things slowly mm-hmm so I've been growing the community of the Pacific Science Institute by having friends come in and and stay at my house including you, my arch-nemesis
W - I had a great time despite the obvious antagonism...
L - and and for you specifically I tried to kill you in several different ways and shark-infested water yeah sure it's great (W - And rought corals) but but yeah basically I've scientists visit and take people out to have fun around the island and really enjoy a good environment where they're free to explore ideas that might be a little bit on the dangerous side to work on while they're in the confines of academia and among their normal colleagues it's a it's a place where you can explore a little bit wilder ideas and I'm really excited to grow this community by by starting to design things to build on the 15 acres I've got that's really in a nice location. So I've been growing things slowly up here and I'm really looking forward to some more progress with it and and growing this community it's in its it's also been a nice balance against working on physics directly because it's it's guaranteed success I mean when you when you have a place in Maui for scientists to come hang out and have a good time that's that's going to happen and also keeps me entertained to have good people coming through
W - that's fantastic so yeah can you just I'm curious from your perspective how do you see the two of us as being divided in our approaches to the community I would definitely say that I I seem to be more connected to the sensibilities of the 'elite science community' I know that I can get their noses out of joint but I'm attracted them very carefully
L - yeah you had a lot fights with those guys (W - okay) yeah whereas I I didn't so my our academic lineages are quite different I mean I went I went to a smaller school I went to UC San Diego I didn't go to Harvard but my advisor they're in particle physics was Roger Dashen but he he passed away well as a graduate student and I finished up my my dissertation under under Henry Abarbanel who also had a background in particle physics but it changed into non-linear dynamics.
W - but in some sense you were a self advised PhD
L - yeah so I was very much self-directed. Henry gave me the freedom to go explore whatever the heck I wanted I had an extraordinary extraordinary amount of freedom as a graduate student and I hit this problem with spinors and that's what I wanted to tackle. I want figure out what they were geometrically and no one else was interested in that problem. But through academia I was a straight-a student you know I did really well I never had any big conflicts
W - was it easy for you?
L - yeah it was I spent a lot of the time surfing I was living on the beach in La Jolla is beautiful is the greatest time in my life okay you know people talk about you know a small you know being in a small pot big fish in a small pond and going to a bigger pond you feel humbled I never really had that experience that was it I was pretty pretty close to the top of my class and really happy about it how everything was going everything was great I got my PhD but there was no way I was going to get a job trying to understand the geometry of spinors when everybody else was doing string theory
W -so you had already accepted that you were unemployable
yeah that's totally unemployable but I invested in Apple stock in the 90s so I had a FU money so I said see you guys let me go surf in Maui and work on the stuff on my own whereas you had a very different experience so you were in Harvard in the math department but studying mathematical physics and as far as I know you were making some really unusual breakthroughs that were very ahead of their time but you weren't welcomed by the the head of the PETA they had people there and so you say you had a conflict from the get-go
W - well I had a very had a very serious dispute about something in mathematics which were called the self-dual equations self-dual yang-mills equations which were related to the regular yang-mills equations which are the equations of force in the standard model but the self-dual yang-mills equations were sort of a square root of those equations and they were very difficult to work with and to solve and I was very confused as to why people were investing in this particular form of these equations when it felt to me that we hadn't asked what constellation of equations these new equations belong to and I'd proposed again spinors as a means of changing the equations and was told that if I mean the exact quote was something like "if spinors had anything to do with the story Nigel who was (Nigel Hitchin) would have told us" like it was just completely (L - yeah) it was bananas and then I got into this issue that well you know spinors have to be quantized as fermions that is they have to be treated as if they were matter inside of quantum field theory but this was not like we weren't doing quantum field theory we were just doing classical geometry of a kind and so none of the arguments I put forward the set of equations which later got recognized and completely changed the field which came through ed Witten and this guy called Nati Seiberg both of them now professors at 'the Institute' (The Institute for Advanced Study) and there was just no room to question why everybody was struggling with these almost intractable equations and just you know getting great results but with so much effort and work so that was like a very weird story whereby you know I think that by 1994 the Harvard Department had woken up to the fact that it was not using the right equations and I'd been actually proposing several sets of different equations but that you know what when this all you know came about late late 80s early 90s there was just no way to to have a productive conversation about it
L - right so you found yourself at odds with the the people you were talking with and you decide to go into finance instead or how'd that happen
W - no I mean I I wanted I was trying to get back to physics and the I was proposing I'd propose three sets of equations
1) one of which had turned out to have been done by somebody else in some place that I didn't know anything about 2) one of which later gets done by Seiberg Witten and then 3) another set of equations that I wanted to connect to the actual standard model and the department was just very concerned that this didn't really have anything to do with actual physics, it was sort of a coincidence in their mind that something that was vaguely physics-y was having great topological results and so there was this you know this fear and I was sent to a guy named Sidney Coleman it was a great quantum theorists and he was much more encouraging than the Harvard math departments any
L - Sidney Coleman was a great guy
W - I mean an unbelievable human being I had two memories of him one of which was that he had all the time in the world for people who had no idea what they were doing and the other was that he didn't suffer fools gladly and then I realized that those are two contradictory images. I unearthed old footage of him he gave this brilliant lecture called quantum mechanics in your face (Transcript) to try to make the quantum have you ever seen this thing I've know it's a work of art you'd love it and it turns out both of these things were really true about him - that he he had if you were full of yourself and you were wrong he would just cut you up into little pieces but if you said "I don't quite understand this" he had all the time in the world to be the greatest of teachers
L - no I mean one of the marks of a good scientist is humility
W - y... No
L - No?
W - No, one of the marks of a good scientist is a dialectic between arrogance and humility if you don't have that's a more subtle and accurate way of putting it yeah well no I just I worry about us extolling the virtues of the humble the mean right the self-effacing and it's just like that's not where the magic happens yeah yeah but
L - you have to have had the arrogance to tackle hard problems right and made some progress but then been kicked back by something that didn't work right and after enough of that you develop some humility but stuff to maintain the arrogance to get anywhere
W - so how do you feel currently about about the community like the professional community you have to know that they regard you with very I mean well I know what's going on I mean there's I got a lot of contempt from strength theorists for getting attention - for putting forward a mathematical model of reality that wasn't strings. And it wasn't complete. It was it had is a model that was proposed that had problems with it and I was forthcoming with the problems in it but I was still saying yeah this is this seems like it's making progress towards the description of reality and has nothing to do with strings and that said alarm bells off all over the place it set off alarm bells for either it's a threat or this guy's a complete crackpot which is more likely and and I got criticisms from but for both
W - I don't think if I were to steel-man their perspective and again you know that I don't share it and I'm willing to fight them and I as I did when you first encountered when I called their immune system in a gentleman known as Jacques Distler. I'm willing to stand up for what it is you're trying to do but I do think that we have to give them their due before we say what's wrong with their perspective. Their perspective is there are lots of constraints that one learns are very difficult to evade when you immerse yourself in standard QFT like they know what it is that is demotivating them it's all the no-go theorems and the the intricacies and the reason they got crazy about string theory. First of all I'm convinced that it was a way of evading the real problems in physics that gave them something to do. It's like like wargames
L - it's an amazing creative piece
well yeah it gives you something to do to keep your chops up that is different from the thing you're supposed to be doing and what they were objecting to is to say "this guy doesn't understand all the things that have to go right in order to do have an improvement on the theory from our perspective. How dare he blithely saunter forth? if we ignored all the constraints on us, we could have fun proposing all sorts of things that also won't work. That was really the responsible version of their critique. Now the irresponsible version of their critique is "hey we have something that isn't working very well how dare he takes something that isn't working very well and get attention"
L - right
W - and maybe funding or maybe destroy the sense that there's only one game in town right and, you know, I was separately lobbying you and them for different things. I wanted you to just say the words like "I understand these are the constraints that will have to be satisfied and I don't have answers and I don't know how difficult they'll be to find but I don't want to be demotivated from the get-go, so please don't immediately tell me all the no-go theorems because any successful theory will probably have to have a period where it's flying in the face of no-go theorems" you know so that's what I wanted to hear from you right
L - I believe I said those things scattered over several interviews at the time
W - somewhat but I think that what they don't Intuit is that you understand how how significant the negative results are the no-go theorems, as they're called, are pretty profound.
L - right I mean there's a theorem called the Coleman-Mandula theorem that prohibits the unification of gravity with the other forces I just blew right through that because it didn't seem to apply in what I was doing W - well I mean really it prohibits naive unification of matter and force and there's a way of evading it using this thing called supersymmetry and supersymmetry is this very weird thing that doesn't have that much mathematical beauty behind it, so the mathematicians know about it they study it a little bit but they're not bananas over L - yeah I'm not either W - the natural world doesn't seem to use it in the expected way but it does so much for theoretical physics that, despite the fact that math is just kind of ho-hum on it, and that the natural world doesn't seem to be using it, it doesn't stop the theoretical physics community from embracing that because it evades this dreaded no go L - it stopped me from from embracing it I never embraced supersymmetry I never I never liked it W - but you didn't evade the problem with it either
L - I mean it got around it W - you think you really got around it? L - the Coleman-Mandula thing? yeah, it requires as one of its axioms that you have to have you know certain it talks about properties of the scattering of particles and you have to have a spacetime of which the scattering occurs and in the theory I put forward the space-time comes out after the symmetry breaking between gravity and forces, so it's only after the symmetry breaking happens when the unification is no longer there... W - yeah I'm sure...
L - ...that you have a space-time and then, in that context, the theorem applies but before the breaking, it doesn't
but my guess is that - I could be wrong about this because I haven't studied exactly what you're talking about - that what's gonna happen is that even with how you claim this arises in your theory they're gonna say in whatever approximation is going to be applied to relatively flat space times close to Minkowski space (L - yeah) that if you've really evaded it in some super-meaningful way you should be able to tell us some theorems about good old quantum field theory and relatively flat space-time
L - right, well I mean it evades it by not satisfying the axioms of the theorem W - do you know what I'm trying to get at? L - it's not evading it in some fantastic way W - you should be able to tell us something really new if you've if your underlying theory (L - mmm...) truly unifies force and matter (L - right...) it would be the case that the approximation of it that is found in ordinary regions that look close to flat, where quantity usual rules of quantum field theory apply it should be telling us something wildly new about that. Can you tell us a new theorem about how it would appeared to unify force and matter in a region that looks close to classical quantum field theory to the standard quarter L - well, I mean, once the theories advanced to the stage where you can get that description (W - yeah) then now it happened but in the initial stages all you can see for certain is that it's not violating the theorem W - I don't know enough about all right how L - we can talk about it after this ok W - so those were my I had these wishes for you, and then I had a the wishes for the community, which is that they would stop being pricks about the whole thing and that they would say "look, we can't keep telling everybody who's not a string theorist, that their theory is dead on arrival and keep saying well we know that our theory doesn't appear to be living in four dimensions and appears to have a bunch of stuff that we don't want and not necessary all the stuff that we do want and maybe there's a huge landscape of different theories that would..." L - yeah at this point I don't think string theories living at all, I think it's an ex-Theory. I think it's pining for the fjords. I've seen nothing but decline since I left this train wreck in progress. W - well this is the problem - is it refuses to take stock of itself and it took a lot more minds than one L - I think that's happening yeah it's certainly the graduate students who are coming up are seeing what's going on with string theory and they're taking stock of the field and they're going in other directions W - so where where do we go next like (L - well...) is there any way, I mean I actually view it as highly demotivating then in essence every new theory is dead on arrival because of the number of things... I mean can we agree that physics has gotten incredibly difficult L - it has. It's difficult by virtue of being so successful I mean that this that W - you can smell that we're almost at the end, at least of this chapter, and we've exhausted everything that we know that has worked previously which is like to vary the assumptions a little bit on everything and that's been spectacularly successful and now it doesn't work anymore and it hasn't worked for almost 50 years L - Right it's incredibly frustrating. I think that's why most people are wise to stay the hell away from it and I think a lot of the smarter minds are going into machine learning or even biophysics or just into other fields or even condensed matter W - how do you feel about that? L - um I feel like I'm out in an island in the middle of the Pacific watching it all unfold from afar while I work on the puzzle myself my own different way W - you're having fun
L - yeah that's that's my prime directive, is to have fun
W - is having fun. And do you think that inducing other people to do this is kind of like maybe the big programs fall apart and we start just becoming individuals trying crazy strategies that probably won't work?
L - yeah I mean there there are undergraduate textbooks and undergraduate courses on string theory (L - yeah) okay and people from undergraduates there's and and there's this culture of arrogance saying string theory is the pinnacle of physics (W - right ) and people are coming up to that and they're becoming and if you're really working on fundamental physics and and the the whole area of string theory has gotten so large in the amount of research done (W - sure) that it just takes an enormous amount of intellectual effort to consume it and to get up to speed to what the current status is of the field and by the time you're there you're so invested then of course what you want to do is go and continue a postdoc in string theory when you graduate. And they're there hundreds of students who are coming up this way and when they get there they go to HEP-Th (of arxiv) like I did this morning you look at...
W - HEP-TH being the high-energy physics theory section where of this thing called the 'archive' (NOTE: which is written arxiv)where all the new papers are found every day
L - yeah and and and the this high-energy physics archive also has a postdoc and job posting board and just just for giggles I wouldn't say okay how many opportunities does the rising string theorist have now and I went and looked and there are all these subfields of physics the condensed matter is a big party because it's so incredibly vibrant and (W - right) and productive right now and you go into high-energy theory and okay there are 30 positions open in North America (W - okay) all right and some of them are open to string theorists, ok, but out of those 30 positions how many of them actually actively want a string theorist and are looking for a string theorist? there's one! One, Eric. So you've got these hundreds of people groomed up saying drink there is the pinnacle of what you can be studying and there's nowhere for them to go well but the field is dying
W - well because it was a baby boomer phenomenon we treated it as if it was an intellectual phenomena but it was actually this weird generational phenomena that this took hold. You know this is a very weird feature of 1951 where Frank Wilczek and Ed Witten - two great physicists, born in the same year - Wilczek is effectively like the last guy to make the train for real physics
L - he's an amazing guy yeah
W - and then Witten born later that year probably more powerful than anyone else alive in terms of his mental abilities, hasn't had a trip to Stockholm because he hasn't been able to make contact with the physical world and almost certainly in any era that wasn't this one this guy would have been to Stockholm once or more
L - yeah and it's in my mind it's a cultural problem we're stuck in this culture of particle physics where we have everybody in the same community studying the same popular direction in full force as if there was lots of data coming in supporting that, and there's not. So what it is is they're going full-bore, full self-supporting force, along direction that in my mind just doesn't describe our universe and what we need is an exploratory phase with physicist students coming up and picking up stuff that they think is interesting and following that direction on their own - branching away from the main herd and by having more explorers going different directions you're more likely to find something good and I guess my hope is that you know some graduate student will listen through this incredibly long and detailed podcast and go look at stuff and say "well that's kind of interesting, maybe I want to learn more about that".
W - do you have any ideas or.. the Pacific Science Institute - is is there any way that our listeners can support it (L - yeah) are you are you a non-profit? L - I'm a 501c3 nonprofit, I'd be very happy to take donations and put those donations to use supporting scientists (W - to diversify. okay...) and these aren't just it's not just supporting physicists. The idea is that, as you said, Science has supported our economy to incredible degree and I don't think scientists have been sufficiently personally rewarded for that. So basically what I want to do is you know give them a nice place to hang out and Maui, enjoy the environment, and work and think on whatever they want undirected while they do it
W - so it's a place to fight groupthink, effectively, with the field
L - while still having community support well solving community support. The problem is I've very limited resource right now I'm basically running this out of my house right I have a big piece of land I have dreams for what I want build on you and
W - I've been there and it's it's incredibly generous that people can hang out and just actually fulfill the promise of dreaming about our world and trying things that they wouldn't feel comfortable trying under the watchful eyes of a departmental chairman is telling them what they need to do to get chair tenure or to win grants do you have any sense of what we should be directing people to do if they're in a position to change the culture of the field. I always want to think like we still have a few old great people that everybody looks up to and they refuse to say something really provocative like - here's the thing that I dream about: we get all of the negative results they're incredibly demotivating. Allow your young people to violate several of them without being string theorists and then insist that they try to pay that back once they've been exploring a theory that in a previous era would have been dead on arrival because somewhere we have to go backwards to go forwards. We have to question something that is rock-solid in all of our minds but isn't actually right. I mean yeah...
L - this is totally right and this sort of cultural inertia that's holding things back is... it's in biology, it's in computer science it's in it's in all fields of science. So I would say just - I mean it's almost the best thing to do just to find people who are really freaking smart and want to work on stuff on their own give them money and support and let them do it
W - I'm on record as saying that we have too much oversight too much transparency and too much accountability it's strangling us
L - yeah it's absolutely true that's absolute true
W - well Garrett I really appreciate you sitting down. It's a hell of an experiment to just even try to have conversations about, you know, what might be the path towards final theories of everything
L - and I'm actually really worried that we hurt most of your listeners
W - well but I do that if we use this at all I'll try to say something at the beginning of the program to try to say what it is that people are listening to so they'll have an idea they're not just gonna stumble in on a podcast and hear people talking about bosons, fermions, E8, quantization and have no idea what's going on. The fact is very few people are invested in this like this but this is the fabric of reality ultimately in a question but how we go about trying to probe whatever's next
L - yeah I think it's amazing I think it's the most significant and intricate and difficult puzzle there is right now for anybody to tackle and to immerse themselves in and I also think it's potentially incredibly rewarding but it's also where the hardest things you can is
W - yeah probably the hardest thing has never been harder yeah
L - that's almost as far as learning to surf
W - okay, well, you've been through the portal with Garrett Lisi here from the island of Maui my arch-nemesis you're welcome to come back anytime and if you're interested in the Pacific Science Institute - its Garrett's attempt to try to figure out how to move science outside of the direct institutional control - you can find him on Instagram I think is Garrett Lisi and on Twitter as Garrett Lisi.
L - Not hard to find
W - all right thanks for joining us
L - thank you Eric