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Asking Physicist Neil Turok Questions About the Universe
July 5, 2024
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The Economist covers math, physics, philosophy, and AI in a manner that shows how different countries perceive developments and how they impact markets. They recently published a piece on China's new neutrino detector. They cover extending life via mitochondrial transplants, creating an entirely new field of medicine. But it's also not just science, they analyze culture, they analyze finance, economics, business, international affairs across every region.
I'm particularly liking their new insider feature was just launched this month. It gives you it gives me a front row access to the economist internal editorial debates where senior editors argue through the news with world leaders and policy makers and twice weekly long format shows basically an extremely high quality podcast whether it's scientific innovation or shifting global politics the economist provides comprehensive coverage beyond headlines.
If you haven't watched Neil Turok's lecture in Rethinking the Foundations of Physics, the debut episode, then click the link in the description before watching this Q&A.
What is your gripe with the multiverse concept? And also, what do you make of the concept of a wave function of the universe? Great, great questions. The multiverse, you know, to be honest, I'm a fairly open minded person. I'm not dogmatic about anything. I think science is precisely about discovering what's true, you know, and the worst thing you can do is bring
too many preconceptions. As I said, my fundamental belief is that the universe teaches us things. We need to be able, willing to learn and you don't learn. If you come to something with a fixed idea you don't learn. So I am open-minded. I wrote a paper with Stephen Hawking essentially about the multiverse. Stephen liked the multiverse idea
But why? Yeah, it's hard to ask him why. I never really took to it. But as I say, I was sort of open minded. And it looked like I mean, I was willing to expose string theory for as long as it looked like it was leading us in an interesting direction. And string theory sort of indicated something like a multiverse. And so I thought, okay, well, let's try it out. You know,
But my problem was that I am only interested in theoretical physics to the extent that it describes nature. That's the only reason I'm interested in it. I'm not interested in it as a mathematical exercise. What I am interested in is this extraordinary fact that human beings, who after all are, you know,
Essentially monkeys who have evolved out of bacteria in the primordial ooze. Somehow, through some means or other, we don't yet understand. We develop the capacity to understand the whole universe. It is just completely insane. And I find that so profound and so wonderful that I'm very happy to devote my life to try to, you know, explore
explore this fact about the universe that we have the capacity to understand it it's it's it's amazing and it's bizarre um so if you like i view my work as homage to this fact okay that for some reason human beings have the capacity and and i shouldn't say human beings supposed to animals i think animals and humans essentially learn in very similar ways and we all have this
Ability to to learn about the world. So i don't want to separate humans from any other form of life. Sure I rather liked your um, what was his name? Bernard castro his view. Oh bernardo castro Yeah, I rather like that point of view that you know, we We we are consciousness and we're all individual Aspects of that as a philosophical view. I I kind of like that. So i'm not a materialist Uh interesting, uh, is that common in your colleagues?
No, but I believe in exploring, you know, and that's what motivates me. When stream theory started to make excuses, and I view the multiverse as the biggest excuse of all time, you know, okay, we can't predict this universe, but we can predict a billion others, you know, I began to lose confidence. And I lost confidence because
You're no longer predicting anything and if you can't predict anything, you can't really check your ideas. You know, you may be just engaging in a fantasy. That's a terrible danger. If you're a theorist, the danger that you're just deluding yourself is enormous, right?
I mean that is the most likely thing. Probably I am deluding myself. Probably we're all deluding ourselves in thinking we can understand the whole universe. And it seems like the ultimate chutzpah to say I can understand the whole universe. So I think the only chance that we are not deluding ourselves is if we really pay attention to facts.
You know, and our facts are always difficult because sometimes they're wrong, the experiments go wrong, they're misleading, etc, etc. They have a lot of issues. However, it is our most reliable source of information. And I think we have to take it very, very, very seriously. So I was interested in the multiverse basically because string theory seemed an effective theory of quantum gravity.
and it seemed inevitable within string theory. But as soon as this possibility of a much more constrained predictor, and I would say principle theory came along, you know, I would grab it with both hands. And I think any theorist would be crazy not to
And what worries me, I mean, okay, our theory, as I've emphasized, is very early stages, baby steps, very encouraging ones, but nevertheless baby steps. We're nowhere near the level of string theory, but I think we have very similar things going on. Namely, we have our whole principle is theoretical consistency.
And we see clues, both from the mathematics and the study six field and from the behavior of the real universe. We see clues that are guiding us towards very deep principles, this conformal symmetry which resolves the Big Bang. So these are very powerful principles. So what I think of at the moment is what we are trying to do. Latham and I essentially and other people slowly getting interested is recreate string theory.
but with a different set of assumption. One is there are four dimensions, that gravity is a theory. String theory essentially postulates that gravity is a sort of spin-off byproduct, the fundamental things are strings. We say no, four-dimensional space-time is the thing you have to quantize, and it's difficult. So we're trying to create a realistic string theory. Basically, that's the way I view it.
with the minimum of ad hoc theoretical ingredients. And so yeah, it's hard to be objective, but I think if I was a string theorist today, I would be extremely worried that the work I'm doing is irrelevant to the real world, because there's so many ways in which string theory does not succeed in describing the real world.
And I would be looking, if not at our approach, for other approaches that are similarly economical, principled, predictive. So yeah, I'm quite happy with this line of research, quite frankly.
It's a relief that not more people are interested in it because we don't have to keep looking over our shoulders. So I highly recommend it to young physicists in particular. Find something which seems to have a compelling internal logic and pursue it to its logical conclusion. That's the very best thing you can do as a theorist.
And what do you make of the concept of a wave function of the universe? Oh, thank you. So Stephen Hawking, of course, whose feet I learned that was a big fan of the wave function of the universe. Personally, the person who invented this was, well, there were two people, John Wheeler, who I was very privileged to know at Princeton. He was a professor at Princeton when I was junior faculty.
I used to drive him home after the physics colloquium because he was rather old and not allowed to drive anymore. So he was an absolutely inspirational figure and just a wonderful human being. Yeah, I'd like to ask you questions about Wheeler another time. Okay, so John Wheeler, you know, I had the privilege of asking him questions. Why is the universe like this and like that?
and he had very sort of um what's the word opinionated no no not opinionated but oracle like uh-huh okay he was he was an oracle okay so he would say very simple things which left you scratching your head and then 20 years later you realize oh my god he was right okay interesting so he invented the concept the word back hole he invented wormhole he invented wave function of the universe
Now, and he had a very, very deep picture of what this meant. The other person who invented it was Bryce DeWitt. Now, Bryce DeWitt was the most technically proficient theoretical physicist in the world in the 1960s. OK, extraordinary person. Again, I had the privilege of seeing him when I was a undergrad at Cambridge. He came to Oxford and gave a lecture and I was there.
He wrote very, very few papers, and the ones he wrote were absolute masterpieces. So Breisterwitz and John Wheeler got together to discuss the Hamiltonian constraint in GR, rather a technical thing in the classical theory, and its quantum realization. And they came up with an equation which was supposed to be the analog of the Schrodinger equation, but for gravity.
Now, Wheeler was very excited initially and called it the wave function of the universe and so on. DeWitt thought more and more about it and came to the conclusion it was nonsense. Okay, so DeWitt a few years later wrote a phrase saying this is the most ridiculous equation in physics and the reason for that is it's a partial differential equation. That's okay.
Like the Schrodinger equation, you have d by dt and d by dx in the Schrodinger equation. So that's all right. It's a partial differential equation. The problem is it is infinite order. Okay. Namely the Schrodinger equation, you know, one d by dt. It's first order in time. It's second order in space. The Wheeler-DeWitt equation for gravity is infinite order p d e. You don't know what the boundary conditions are.
And you don't know which solutions you would need an infinite number of boundary conditions. And if you just take this equation at face value, there's an infinite number of solutions. So, you know, who knows what it means? It's it's, I would say, just like the Schrodinger equation, it's a useful technical device, but it doesn't really give you much insight.
into what the initial condition was at the big bang or anything like that. Now Hawking took well he tried to define the no boundary proposal and Hawking's proposal is was the motivation for our proposal of a mirror. Hawking had a kind of even more beautiful proposal which is that you take four-dimensional space-time
and you round it off at the beginning so there is no boundary there's no beginning it's just you so imagine a sort of rounded surface and we we live on the on the final edge and so he called it no boundary proposal this was rather nicely formulated in the part in a path integral way but Hawking then tried to use the Wheeler-DeWitt equation
to examine the path integral, because path integrals are rather difficult. They're harder than the Schrodinger equation. In quantum mechanics, Schrodinger solved the hydrogen atom using his equation, but to solve the hydrogen atom in the path integral took 50 years, or probably more, 60 or 70 years. So it technically was just much more difficult to use path integrals. So nevertheless, Hawking formulated these theories of path integral
and then he tried to use the Willard-Witt equation. When he did that, he sort of cheated. He put in some boundary conditions, but they don't really make any sense. So yeah, I would say the wave function of the universe, you know, if you literally deal with the Willard-Witt equation, you better find a way of dealing with infinite order partial differential equations
showing there are sensible boundary conditions showing that there are unique solutions all of that if you want to deal with path integrals which is more geometrical the sum of the geometries you know is a more intuitive geometrical thing then you know deal with path integrals i think all of these papers on the wave function of the universe and there are tens of thousands of papers now are not really making much progress
That's my view. I mean, they're just kind of recycling the same old ideas, which haven't really led anywhere. The reason I lost confidence in Hawking's proposal is it gave the wrong predictions. Hawking's proposal did not produce a universe like ours, whereas our mirror hypothesis does. Our mirror hypothesis predicts a flat, spatially flat universe, homogeneous and isotropic,
which looks like ours so i would say it's just an alternative to hawking just like hawking we have no extra input you see i what what i think doesn't really make sense philosophically or at least i shouldn't say philosophically maybe it does make sense philosophically to have a creator but uh what doesn't make
What is not very appealing, let's put it that way, scientifically, if I want a predictive theory, I do not want the freedom to input stuff at the Big Bang. I want everything to be self-contained. I'm going to write down some laws of physics and I want those laws to define their own starting point. So usually laws are seen as distinct from boundary conditions. Exactly.
So Hawking's hypothesis, the no boundary proposal, had the laws of physics, namely Einstein's theory of gravity, define its own starting point. That was what was so elegant about it. The mirror hypothesis is the same. You say the laws of physics and the CPT hypothesis that the universe doesn't violate CPT, those define the boundary condition.
Yes. Now, how do you explain that our universe isn't conformally invariant?
so right great question around you and it's not so there must be something breaking it yes absolutely so um in order to resolve the big bang singularity you need this conformal symmetry right i mean that seems very intuitive if space shrinks to nothing the only way to make sense of that is if that is just an artifact of your description you've somehow used variables which shrink to nothing
You can map the problem to another problem in which space doesn't shrink to nothing, shrinks to a finite mirror, and now you have a coherent description where all the equations work and so on. So it seems that, at least from our point of view, you have to have conformal symmetry to have a sensible description of the Big Bang. That does not mean you need conformal symmetry today.
Because between the Big Bang and today, you can break conformal symmetry. Okay, so this theory, so there needs to be a theory of conformal symmetry breaking. Now we're very familiar with this in the Standard Model. In the Standard Model, there's a symmetry group called SU2-whee, which rotates neutrinos into, neutrino into the electron, for example. It's an SU2 symmetry and the laws of physics have that as a fundamental symmetry.
Nevertheless, that is what we call spontaneously broken by the Higgs field. When the Higgs field switches on, it sort of picks a direction in this SU2 symmetry space, which defines the electron and the neutrino. An electron is the direction along the Higgs field, neutrino is the orthogonal direction. And so the
notion that the laws of physics do have conformal symmetry but that symmetry gets spontaneously broken. This is an extremely attractive hypothesis. Having said that, physicists have been working for 50 years on various ways to break the conformal symmetry. I can put it a different way. You see, the standard model
If I switch off the Higgs mass, there's one parameter in the standard model which breaks conformal symmetry. Only one. And that's the mass of the Higgs field. Right. It's the only parameter with dimensions of mass. Okay. And it's how you get the mass of the Higgs field. Without that parameter, the rest of the theory is conformally invariant.
That's actually a consequence of renormalizability. Renormalizability is a very special property in four-dimensional theories and it requires dimensionless couplings and when you have dimensionless couplings you have conformal symmetry. So if you want to explain the breaking of conformal symmetry is actually explaining
the origin of the Higgs mass. These things are very tightly related. What is very exciting, I didn't mention it in my talk, but there's a new development, very new development, which is a new idea for explaining the Higgs mechanism without inputting the Higgs mass. Okay. Okay. And this is
This is a, he's essentially a quantum field theorist who works in lattice gauge theory and also high temperature nuclear matter. So a real physicist, it's not a string theorist, and he has pointed out, you see, yeah, I need to explain a little bit more. How do we explain the origin of mass, okay, and mass scales?
Now, in one case, in quantum chromodynamics, the explanation is very natural. Why do I say that? You see, quantum chromodynamics, the theory of a strong force, is what's called asymptotically free. It means that as you go to higher energies, the coupling constant goes to zero. As you come down in energy, the coupling diverges.
And the theory becomes strongly coupled. You can say the following. Let's imagine I fix the strong coupling constant to some number like one thirtieth. That that's what you get by extrapolation at the Planck scale. And I now so the very, very high energies at the Planck scale. And I now ask, what is the scale at which it becomes one? So it's a thirtieth at the Planck scale.
And ask what energy scale does it become one? And that energy scale is the scale of the mass of the proton. OK, so in other words, the proton mass is only one GV, whereas the pipe mass is 10 to the 19 GV. But that difference is not hard to explain. The reason it's not hard to explain is because the coupling constant runs only logarithmically with energy.
And log of 10 to the 19 is only about, what, 40 or something, 35 or 40. And so logarithmic running of couplings gives you a very natural explanation of enormous mass hierarchies. So in the case of QCD and the mass of a nucleon, the mass of the proton,
There isn't a fine tuning problem. You just say, okay, this for some reason, the coupling constant, the alpha three, the fine structure constant for the strong interaction is about a 30th at the point scale. When I come down in energy scale, when I hit one GV, it's wrong. And that defines the mass of the bound states of particles, the proton. So this new explanation of the Higgs mechanism is like that.
It claims that there's a way to formulate the theory where there's no mass scale put in. All the mass comes about because of the running of coupling constants with energy scale, which is a quantum effect. So another way of saying is that all masses are quantum in origin. And so this new work shows that
claims to show that it's not quite complete. He hasn't actually predicted all the details. He's just made it plausible that it can work. It shows that the Higgs mechanism and the Higgs mass can be explained very naturally as being due to quantum effects in a certain kind of model. That kind of model
Is probably the simplest quantum field theory you can define. It's called lambda fighting force theory. And what I've shown recently is that model maps perfectly to our dimension zero scalars. What do you mean it maps perfectly to them? Well, it's quite technical, but so I'll just say a few words. They may not. Sure. You can also say what the name of the paper is so I could put that on screen. This is not written up yet.
i see okay this is in very recent work we haven't written this up so this was just last month when i was at perimeter sure give the cliff notes if you don't mind sure i mean it's still secret so yeah i think so my i don't want to say too much about it because my students are busy working on it and they need this uh they they need these papers of course of course okay so then how about this
Do you think the Higgs is a fundamental particle? In our explanation of the cancellation of the vacuum energy and the conformal anomalies, we cannot have a fundamental Higgs. Interesting. The Higgs field cannot. It is inconsistent. This cancellation mechanism says there are no fundamental Higgs.
It also says we have to introduce 36 dimension zero fields. The logical inference from those two facts is somehow the Higgs field must be made of the 36 dimension zero fields. It must be a composite. Okay. And this recent work by Romache is very exciting because it points to that being possible.
So I think we are on the verge of a reformulation of the standard model based on dimension zero fields without mass parameter being needed to be stuck in by hand. This would automatically solve what's called the hierarchy problem. The hierarchy problem is the difference between the weak scale
Or the proton mass, if you like, in more simple terms, the difference between proton mass and the Planck mass. You know, they differ by 19 orders of magnitude. Where did that come from? This would be naturally explained if all mass scales arise in the same way due to the running of couplings, which is the quantum effect.
So I think we're seeing hints of a solution of the hierarchy problem. By the way, the hierarchy problem was the main motivation for looking at supersymmetry. You know, much less compelling picture with all kinds of extra particles and parameters and assumptions. And so supersymmetry became big precisely because people thought it might solve the hierarchy problem.
What we're seeing now is a far more economical solution which basically involves sort of tampering with the vacuum in quantum field theory using these funny dimension zero fields but you know if we're right this is going to revolutionize particle physics. You mentioned that you're not a fan of data fitting. Yes.
And then you also mentioned that there's the introduction of these 36 fields. Right. So do you see that as a form of data fitting? No. What happens is, I mean, it's a very curious numerology that when I say there are 36 fields, we have to explain the number 36. We don't yet have an explanation for it. So what we found is the strange coincidence
That basically the vacuum energy per mode of the fields in the vacuum. So every quantum field in the standard model has an infinite number of modes. You can think about these as waves of different wavelengths in the different direction. So there are infinite number of these modes. Every mode has some vacuum oscillation and contributes some energy. So in the standard model, the energy in the vacuum is just basically some
overall number times a sum of integers. You know, I get some number times the number of spin zero fields, another number times the number of spin half fields, and then the spin one fields. Similarly, with the violations of local conformal symmetry, which I mentioned, this is called the conformal anomaly
it's also a sum of integers with strange coefficients okay so all of that is a consequence of quantum field theory that these if you put all the they're actually three of these kind of violations which happen and they're all sums of integers so you get three sums of integers with various coefficients including some fractions and you want all three sums to be zero
We discovered that if we add these strange dimension zero fields, and if we add precisely 36 of them, then all three anomalies cancel the vacuum energy and two independent contributions to these violations of the local scale symmetry. So suddenly we get this much more beautiful theory. It demands 36. I know three parameters, right? It requires 36.
Now, where did the 36 come from? There are various suggestions as to where it comes from. 36 is the dimension of a group, in fact two groups, simple groups. One is sp8 and the other is s09. These groups are related to twister theory. Twister theory has a sort of bigger version which involves sp8
And what's very tantalizing is that maybe, you know, once we understand that connection better, we'll see that we're forced to 36. Preferably by gravity. We want to see that gravity, as gravity does look much nicer in twister, its twister representation, there are no new parameters in the twister representation. The twister representation may then lead us to this bigger
picture in which there are 36 fields. Coincidentally, I should have mentioned, twister theorists who are much more on the mathematical end than we are, have shown that in the Feynman path integral for gravity, they need to introduce 36 dimension zero fields to make sure that the twister path integral
equals the gravitational path integral and the amazing thing about their result is it's not perturbative you see our result is only true for three fields it's the very it's the most naive possible calculation their result is true to all orders right these are serious mathematicians and they've shown that introducing these dimension zero fields cures these problems
non-perturbatively okay so that's very spectacular so we are hoping that our work ultimately connects with theirs if it does then you know the number is is actually going to be fixed it's not a free parameter so that's still to come now having said that the way we treat the 36 fields is we you know naively have i got 36 fields that have a huge number of parameters and coupling them all
You know, I could write down five, you know, let's say the kinetic term and then a potential term with 36 different fields that have a very huge number of parameter space of potentials. The way we use these fields, they are not allowed to have a potential. OK, so that's not possible. And the way we use them is we treat them all equally.
So when they contribute it's 36 all giving exactly the same. That's, as I said, there are assumptions in our calculation. We always make the simplest assumption and that assumption is that all 36 fields contribute equally. So we've tried to be as minimal as possible with this theory. It doesn't mean that, you know, that there aren't three parameters for sure because this is still under construction.
Uh, what we hope is that as we understand it more and more deeply, we will see that, you know, there are constraints which come in, which, which force you to make these choices. And, uh, you know, we're hoping that ultimately there, there aren't any, uh, free parameters, uh, in the, in this game, of course, that's a very ambitious dream. Um, yes, right.
So this is the Boyle-Turrock model, correct? Yes. That's what people can search if they want to hear more. Yes. They can just look for my name, Latha Boyle's name, and all of our papers on the archive. So the 36. Yes. There are also 36 parameters in the gravity spin connection. Correct. Is that a numerical coincidence? Other people have pointed this out that there are many formulations of Einstein's theory of gravity. The original one, you have a metric.
with 10 components and then rather in a rather ugly way you have a Christoffel connection which has 40 components. Okay, so you have all these different fields in fact in own sense here of gravity. Now what happened after that is other people discovered different formulations of gravity which are somehow more economical and more beautiful, more geometrical and there are many of these
one involves fear binds and spin connections. And in fact, you have to go to that representation to describe fermions in gravity. You have to use fear binds and spin connections. But these things have different numbers of fields than Einstein's formulation. And these as you mentioned,
There's a particular formulation of of gravity called a plebansky formulation which emphasized that you could write down Einstein's equations very very beautifully if your fundamental object was not the metric metric but was an anti-symmetric two-component tensor called a B field and this B field is
So an anti-symmetric tensor with four, so two indexes, each one can run over four values, has six values. This knee field has both space time indices, both a mu, a new index, a sort of coordinate indices, and also Lorentz indices, also anti-symmetric. And so the six of one and six of the other, and you get 36. So
People have pointed out that maybe the 36 is somehow telling us about this formulation of gravity. That's very tantalizing. We don't know whether that's true. I think the connection with twisters is also a hint that that may be a better formulation of gravity. So, you know, we're trying to do something very difficult here, which is write out a consistent
you know, quantum path integral for gravity. And certainly the naive one is not the full story. So we have to find the right variables in which to write that path integral for gravity. And as I say, there are a couple of hints that 36 is going in that direction. But so far, these are just kind of numerical coincidences.
Where does dark energy come from? Well, it's a good question. I mean, as you know, as I said in the talk, it's the simplest form of energy there is. It's just uniform in space, uniform in time. So you view it as another constant, another knob to fiddle with? I am not happy about that, but that is the current state of thing. In the part of my talk I didn't give,
I was going to talk about thermodynamics and the thermodynamics of the universe. You see, I think the most profound explanations in physics are ones which use thermodynamics. Entropy. Entropy is the most profound concept in physics. It's like how many ways can you arrange something, right?
More generally you can say entropy tells you, you know, if I have limited information about the world and I want to know what's going on in the world, what I do is maximize the entropy. I say what are the greatest number of microstates of the world compatible with what I do know and then most likely the world will be
in one of those states which maximizes the entropy, right? The most likely states are the most numerous. So the notion of entropy I think is sort of beyond the laws of physics. It's saying given probabilities, given that nature is probabilistic and we think quantum mechanics is probabilistic, given that the laws of physics are fundamentally probabilistic, the laws of probability kind of
supersede everything else and so thermodynamic explanations are always the best ones because basically they say no matter what you do with the laws of physics you're going to get the same answer okay so we have a new thermodynamic explanation for the geometry of the universe you based on hawking's ideas and our mirror boundary condition etc etc but it is
What about lambda? So what is lambda? What is the cosmological constant? Now in thermodynamics, the basic idea is you constrain certain quantities. So let's say I've got a box of gas, certain number of particles, certain amount of energy, and I find the maximum entropy state.
Which is the equilibrium one, you know, where all the particles are essentially evenly distributed and they've shared out all the energy and so on But you need to impose the right constraints So in the case of particles in a box, it would be the number all the conserved quantities number of particles total amount of energy Actually the total momentum of the particles the total angular momentum. You can constrain those things now in
Gravity, everything is geometrical, okay, and that makes the theory very unique. You say, you know, how do I define the theory? Well, I have to deal with geometrical quantities. Probably the most obvious geometrical quantity you can think of in a four-dimensional space-time is the volume, the total volume of the space-time.
Right. I integrate over space and time and I get a four volume. So now you ask, what is the cosmological constant? Well, it is the term in the action for gravity, which multiplies the full volume. So lambda multiplies the full volume. If I do thermodynamics on gravity, lambda is analogous to temperature or chemical potential. You know, what is temperature?
Temperature says when i do thermodynamics i take the energy in the system and i multiply it by one of the kt so i have in my Statistical ensemble i've got the boltzmann factor e to the minus energy of a kt the best way to think of temperature it is just One of the kt is the quantity multiplying the energy in the statistical ensemble And i just dial that to get the average energy in the box
so you can say you would dial the cosmological constant to get the full volume of the universe okay that's the way in which it occurs in in in gravity so essentially it's saying that you know um if i want to describe particles in a box i need a temperature i just say what if i tell you if i ask you what's the most likely configuration particles in a box
And I don't tell you the energy and I don't tell you the number of particles. You can't say anything. You need some information. Yes. So I can say a box of gas at temperature, you know, 30 degrees centigrade and with a certain density of particles, you know, a certain number of particles in the box. Then I've defined it. So it appears the way the cosmological constant enters physics
Is in the same way as temperature does or chemical potential which we use to describe the number of particles And it controls the volume of the universe now then it's up to you what you fix and what you predict So you can fix the number of particles or I could say no. I've got a box of gas at certain pressure Pressure and temperature, you know some measurable things
Then predict how many particles there are. Predict the energy in the box. But you need to know a certain number of things to predict other things. Lambda might be just one of those things you need to know to predict other things. When we calculate the entropy of cosmology, it's very tantalizing. We find that the entropy is greater
The smaller lambda is, and the thermodynamics only make sense if lambda is positive. So basically, roughly speaking, it predicts that the cosmological constant is as small as it can be, but it has to be positive. And that's very compatible with what we see. But it's only halfway there. You know, we need to now understand what are the other constraints
Should we be fixing lambda? Should we be fixing the full volume? Maybe the full volume is quantized. You know, we haven't put that in yet. When you quantize the full volume, maybe lambda only takes discrete values. So I think we're seeing glimpses of the role of lambda, but at the moment we don't really understand what it is.
Or how to use it. We can fit it to the universe. That's not a theory. That's just a fit. Um, but what you hope is a sort of deeper understanding will lead you to understand the value. But ultimately, you know, the value. So this may sound a little anthropic and I'm not anthrop. I don't like the anthropic principle because I essentially, I think it's very abused. Um, but I'm not averse to
selection effects. There are selection effects. You know, we live on the surface of a habitable planet. That's not a surprise. That's where we evolved, you know. And so it sort of seems foolish given that there are, you know, 100 billion stars and 100 billion galaxies and 100 billion stars in each galaxy.
We don't usually say, you know, predict why the Earth is habitable. I mean, we're here because it's habitable. So that's fine, but you shouldn't... You see, when people use the anthropic principle in cosmology, I think they do it in
What yeah technically you say that they don't know what the measure is they don't know how much weight to assign any particular cosmos and then what they typically do is say oh this this one looks like the one we see the universe had to be like the one we see because we're here okay and so maybe it has to be like that just because we're here
And that gets them off the hook as actually explaining anything at all. But I don't want to do that. I want to understand as much as we can about the universe with as few assumptions as possible.
So I don't mind there being a selection effect at some point. Yeah, I'm not understanding the difference between the selection effect and then what the people who have a variety of values and then they say that, well, we happen to find ourselves at one of these values. Right. And it's because that value is small. I don't see the difference. Imagine you imagine you have multiverse. Sorry, is it the case that in the planet case we have a measure? Yes, because we can see how many other habitable stars there are habitable planets surrounding a star there? No, no.
In the planet case, we have not seen any other, so far, any other planet that's remotely habitable. Maybe there's some recently. But in the planet case, we have observations indicating that it's really unusual for life to arise. I mean, certainly it seems there's no other life in the solar system.
and when we when we look at other stars and planetary systems typically they seem not to be suitable for at least our kind of life so it it seems that life is rare right and maybe very very rare for all we know we're unique in in in the observable universe now what people do in the
Much much further. And say, you know, I've got this 10 to the 1000 universes in string theory. Maybe only universes like ours are habitable. And, and therefore, all the features that I can't explain of our universe using string theory, I'm going to explain this way.
so basically it's just an excuse it's a way of letting yourself off the hook that you will never explain the value of the cosmological constant you will never explain you know various other cosmological parameters just because you're saying oh there had to be that way because otherwise we wouldn't be here so i think that's a non-explanation i see what i what what i believe there may be
I think all the indications are there may be an explanation which is way better than that, which basically says that in a certain category of, well let's see,
you see okay now i'm going to get very spacey and refer to bernardo bring it on so bernardo said yeah bernardo says that you know reality is essentially a manifestation of consciousness right and and that the world at a deep level is all about information and this consciousness unified
Somehow processes this information, right? So I think that's a very appealing perspective It's not very materialistic And as he rightly said it's not very scientific because at this point we don't know how to test it But we can't disprove it either So now if you adopt this perspective and you say within this realm, however consciousness works
You know, it is possible for things like universes to emerge. If the laws of physics are quantum mechanical, or actually just probabilistic, there will be a number of possibilities, you know, and given that I, my, what did he call it, my dissociated, I'm quoting his words, given that my dissociated consciousness
right, has only partial awareness. You know, maybe universes like the one we see are the most probable. Now, how do we even test this? How do we try to turn this into science? I would say the best way we do it is by taking the laws of physics we know,
Use analogies, use mathematics, try to make a logical framework where we calculate probabilities. And our calculations of entropy and gravitational entropy are very much going in this direction. It may be that in this space of information processed by consciousness, you know, certain values are preferred, most likely.
If it is a thermodynamic explanation, that will be fairly independent of the laws of physics. You know, maybe it probably will depend on gravity in some way, but not on the fine details. And I think it may be that we can at least approach such an explanation of the cosmological constant of the basic structure of spacetime. And that seems to me a very fruitful
way of exploring you know so instead of posing the question like i've measured this number lambda it's 10 to the minus 20 and 120 in plank units you know okay what a massive puzzle that is you know don't try to just predict the number try to predict everything and use all the information we have try to make your framework compatible with everything we see and as you succeed in refining and further and further formalizing
the laws the unified laws of physics with all the observations we have as you succeed in doing that if nature is unified you will see these unifications happen so maybe we're right maybe we have explained the fluctuations coming out of the big bang that's great now that gives us confidence in the vacuum
Right? How do we understand lambda? Well, lambda is of energy in the vacuum, right? That's what lambda is. We've made a step forward to it because we've cancelled infinity. You know, we had a terrible paradox that the vacuum energy was infinite. In our new theory with these dimension zero fields, at least the leading infinity is cancelled. Now we're dealing with finite numbers. So let's just keep developing that. Keep developing the machinery and the formalism
trying to remove kind of logical inconsistencies as we go and maybe this will actually end up converging on the lambda. If lambda currently in our current perspective takes this ridiculously small value right but as I explained if things only depend logarithmically on energy scale you can get very large numbers appearing out of very modest numbers
You know, equivalently, you can say if I exponentiate 30, I get a huge number. Right. But it's only because you didn't understand the logarithm that you thought this is ridiculous. So we do know many things in physics change logarithmically, most likely, you know, the law, most likely the log of lambda is the physical is the physical parameter.
And if the log is a physical parameter, then there's no real puzzle about it being so tiny. And perhaps the log had to take a particular value in order for the physics to be consistent. So I wouldn't claim we are near to explaining why lambda is so small. What I would say is we're developing a framework which is unified
In so far as it goes, it is complete. It accounts for everything we see. It accounts for all the known laws of physics. And yeah, let's push it further. I wish there were many other frameworks like ours competing. You know, that's healthy science. What I fear at the moment is that string theorists have essentially gone off into mathematical land, mathematics land,
And they're busy exploring N equals four super young males and, you know, all kinds of, um, ADS five cross S five, you know, all of sort of totally unrealistic universes. Um, and yeah, they, what I worry about is they are never to return. When you take, you take one wrong turning in theory land and you probably, and if you're dogmatic, you will never come back.
And that's the biggest danger in the whole field of theoretical physics is you make one mistake. I mean, it's so ambitious, you know, to explain everything that you make one mistake. If you insist on sticking to that mistake, you're never going to come back to the right picture. So I think much more likely to me is is if you are adaptable. If you quickly realize when you've gone wrong,
Neil, I appreciate you spending so much time with myself, with the audience here and
I appreciate you being the inaugural talk on the rethinking the foundations of physics. What is unifications series? Thank you. And people who don't know what that is, there's a talk that you can go click on that gives a lecture that Neil just gave approximately one hour in length. And it's a fantastic talk that goes over the mysteries of the universe explained economically in a simple manner. So thank you. Thank you. You're very kind. Thanks a lot. It's an absolute pleasure.
Firstly, thank you for watching, thank you for listening. There's now a website, curtjymongle.org and that has a mailing list. The reason being that large platforms like YouTube, like Patreon, they can disable you for whatever reason, whenever they like.
That's just part of the terms of service. Now, a direct mailing list ensures that I have an untrammeled communication with you. Plus, soon I'll be releasing a one-page PDF of my top 10 toes. It's not as Quentin Tarantino as it sounds like. Secondly, if you haven't subscribed or clicked that like button, now is the time to do so. Why? Because each subscribe, each like helps YouTube push this content to more people like yourself
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There's also just joining on YouTube. Again, keep in mind it's support from the sponsors and you that allow me to work on toe full time. You also get early access to ad free episodes, whether it's audio or video. It's audio in the case of Patreon video in the case of YouTube. For instance, this episode that you're listening to right now was released a few days earlier. Every dollar helps far more than you think. Either way, your viewership is generosity enough. Thank you so much.
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▶ View Full JSON Data (Word-Level Timestamps)
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"text": " The Economist covers math, physics, philosophy, and AI in a manner that shows how different countries perceive developments and how they impact markets. They recently published a piece on China's new neutrino detector. They cover extending life via mitochondrial transplants, creating an entirely new field of medicine. But it's also not just science, they analyze culture, they analyze finance, economics, business, international affairs across every region."
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"text": " I'm particularly liking their new insider feature was just launched this month. It gives you it gives me a front row access to the economist internal editorial debates where senior editors argue through the news with world leaders and policy makers and twice weekly long format shows basically an extremely high quality podcast whether it's scientific innovation or shifting global politics the economist provides comprehensive coverage beyond headlines."
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"text": " If you haven't watched Neil Turok's lecture in Rethinking the Foundations of Physics, the debut episode, then click the link in the description before watching this Q&A."
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"text": " What is your gripe with the multiverse concept? And also, what do you make of the concept of a wave function of the universe? Great, great questions. The multiverse, you know, to be honest, I'm a fairly open minded person. I'm not dogmatic about anything. I think science is precisely about discovering what's true, you know, and the worst thing you can do is bring"
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"text": " too many preconceptions. As I said, my fundamental belief is that the universe teaches us things. We need to be able, willing to learn and you don't learn. If you come to something with a fixed idea you don't learn. So I am open-minded. I wrote a paper with Stephen Hawking essentially about the multiverse. Stephen liked the multiverse idea"
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"text": " But why? Yeah, it's hard to ask him why. I never really took to it. But as I say, I was sort of open minded. And it looked like I mean, I was willing to expose string theory for as long as it looked like it was leading us in an interesting direction. And string theory sort of indicated something like a multiverse. And so I thought, okay, well, let's try it out. You know,"
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"text": " But my problem was that I am only interested in theoretical physics to the extent that it describes nature. That's the only reason I'm interested in it. I'm not interested in it as a mathematical exercise. What I am interested in is this extraordinary fact that human beings, who after all are, you know,"
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"text": " Essentially monkeys who have evolved out of bacteria in the primordial ooze. Somehow, through some means or other, we don't yet understand. We develop the capacity to understand the whole universe. It is just completely insane. And I find that so profound and so wonderful that I'm very happy to devote my life to try to, you know, explore"
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"text": " explore this fact about the universe that we have the capacity to understand it it's it's it's amazing and it's bizarre um so if you like i view my work as homage to this fact okay that for some reason human beings have the capacity and and i shouldn't say human beings supposed to animals i think animals and humans essentially learn in very similar ways and we all have this"
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"text": " Ability to to learn about the world. So i don't want to separate humans from any other form of life. Sure I rather liked your um, what was his name? Bernard castro his view. Oh bernardo castro Yeah, I rather like that point of view that you know, we We we are consciousness and we're all individual Aspects of that as a philosophical view. I I kind of like that. So i'm not a materialist Uh interesting, uh, is that common in your colleagues?"
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"text": " No, but I believe in exploring, you know, and that's what motivates me. When stream theory started to make excuses, and I view the multiverse as the biggest excuse of all time, you know, okay, we can't predict this universe, but we can predict a billion others, you know, I began to lose confidence. And I lost confidence because"
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"text": " You're no longer predicting anything and if you can't predict anything, you can't really check your ideas. You know, you may be just engaging in a fantasy. That's a terrible danger. If you're a theorist, the danger that you're just deluding yourself is enormous, right?"
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"text": " I mean that is the most likely thing. Probably I am deluding myself. Probably we're all deluding ourselves in thinking we can understand the whole universe. And it seems like the ultimate chutzpah to say I can understand the whole universe. So I think the only chance that we are not deluding ourselves is if we really pay attention to facts."
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"text": " You know, and our facts are always difficult because sometimes they're wrong, the experiments go wrong, they're misleading, etc, etc. They have a lot of issues. However, it is our most reliable source of information. And I think we have to take it very, very, very seriously. So I was interested in the multiverse basically because string theory seemed an effective theory of quantum gravity."
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"text": " and it seemed inevitable within string theory. But as soon as this possibility of a much more constrained predictor, and I would say principle theory came along, you know, I would grab it with both hands. And I think any theorist would be crazy not to"
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"text": " And what worries me, I mean, okay, our theory, as I've emphasized, is very early stages, baby steps, very encouraging ones, but nevertheless baby steps. We're nowhere near the level of string theory, but I think we have very similar things going on. Namely, we have our whole principle is theoretical consistency."
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"text": " And we see clues, both from the mathematics and the study six field and from the behavior of the real universe. We see clues that are guiding us towards very deep principles, this conformal symmetry which resolves the Big Bang. So these are very powerful principles. So what I think of at the moment is what we are trying to do. Latham and I essentially and other people slowly getting interested is recreate string theory."
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"text": " but with a different set of assumption. One is there are four dimensions, that gravity is a theory. String theory essentially postulates that gravity is a sort of spin-off byproduct, the fundamental things are strings. We say no, four-dimensional space-time is the thing you have to quantize, and it's difficult. So we're trying to create a realistic string theory. Basically, that's the way I view it."
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"text": " with the minimum of ad hoc theoretical ingredients. And so yeah, it's hard to be objective, but I think if I was a string theorist today, I would be extremely worried that the work I'm doing is irrelevant to the real world, because there's so many ways in which string theory does not succeed in describing the real world."
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"text": " And I would be looking, if not at our approach, for other approaches that are similarly economical, principled, predictive. So yeah, I'm quite happy with this line of research, quite frankly."
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"text": " It's a relief that not more people are interested in it because we don't have to keep looking over our shoulders. So I highly recommend it to young physicists in particular. Find something which seems to have a compelling internal logic and pursue it to its logical conclusion. That's the very best thing you can do as a theorist."
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"text": " And what do you make of the concept of a wave function of the universe? Oh, thank you. So Stephen Hawking, of course, whose feet I learned that was a big fan of the wave function of the universe. Personally, the person who invented this was, well, there were two people, John Wheeler, who I was very privileged to know at Princeton. He was a professor at Princeton when I was junior faculty."
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"text": " I used to drive him home after the physics colloquium because he was rather old and not allowed to drive anymore. So he was an absolutely inspirational figure and just a wonderful human being. Yeah, I'd like to ask you questions about Wheeler another time. Okay, so John Wheeler, you know, I had the privilege of asking him questions. Why is the universe like this and like that?"
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"text": " and he had very sort of um what's the word opinionated no no not opinionated but oracle like uh-huh okay he was he was an oracle okay so he would say very simple things which left you scratching your head and then 20 years later you realize oh my god he was right okay interesting so he invented the concept the word back hole he invented wormhole he invented wave function of the universe"
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"text": " Now, and he had a very, very deep picture of what this meant. The other person who invented it was Bryce DeWitt. Now, Bryce DeWitt was the most technically proficient theoretical physicist in the world in the 1960s. OK, extraordinary person. Again, I had the privilege of seeing him when I was a undergrad at Cambridge. He came to Oxford and gave a lecture and I was there."
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"text": " He wrote very, very few papers, and the ones he wrote were absolute masterpieces. So Breisterwitz and John Wheeler got together to discuss the Hamiltonian constraint in GR, rather a technical thing in the classical theory, and its quantum realization. And they came up with an equation which was supposed to be the analog of the Schrodinger equation, but for gravity."
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"text": " Now, Wheeler was very excited initially and called it the wave function of the universe and so on. DeWitt thought more and more about it and came to the conclusion it was nonsense. Okay, so DeWitt a few years later wrote a phrase saying this is the most ridiculous equation in physics and the reason for that is it's a partial differential equation. That's okay."
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"text": " Like the Schrodinger equation, you have d by dt and d by dx in the Schrodinger equation. So that's all right. It's a partial differential equation. The problem is it is infinite order. Okay. Namely the Schrodinger equation, you know, one d by dt. It's first order in time. It's second order in space. The Wheeler-DeWitt equation for gravity is infinite order p d e. You don't know what the boundary conditions are."
},
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"start_time": 762.415,
"text": " And you don't know which solutions you would need an infinite number of boundary conditions. And if you just take this equation at face value, there's an infinite number of solutions. So, you know, who knows what it means? It's it's, I would say, just like the Schrodinger equation, it's a useful technical device, but it doesn't really give you much insight."
},
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"text": " into what the initial condition was at the big bang or anything like that. Now Hawking took well he tried to define the no boundary proposal and Hawking's proposal is was the motivation for our proposal of a mirror. Hawking had a kind of even more beautiful proposal which is that you take four-dimensional space-time"
},
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"text": " and you round it off at the beginning so there is no boundary there's no beginning it's just you so imagine a sort of rounded surface and we we live on the on the final edge and so he called it no boundary proposal this was rather nicely formulated in the part in a path integral way but Hawking then tried to use the Wheeler-DeWitt equation"
},
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"end_time": 873.541,
"index": 31,
"start_time": 845.043,
"text": " to examine the path integral, because path integrals are rather difficult. They're harder than the Schrodinger equation. In quantum mechanics, Schrodinger solved the hydrogen atom using his equation, but to solve the hydrogen atom in the path integral took 50 years, or probably more, 60 or 70 years. So it technically was just much more difficult to use path integrals. So nevertheless, Hawking formulated these theories of path integral"
},
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"start_time": 874.224,
"text": " and then he tried to use the Willard-Witt equation. When he did that, he sort of cheated. He put in some boundary conditions, but they don't really make any sense. So yeah, I would say the wave function of the universe, you know, if you literally deal with the Willard-Witt equation, you better find a way of dealing with infinite order partial differential equations"
},
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"text": " showing there are sensible boundary conditions showing that there are unique solutions all of that if you want to deal with path integrals which is more geometrical the sum of the geometries you know is a more intuitive geometrical thing then you know deal with path integrals i think all of these papers on the wave function of the universe and there are tens of thousands of papers now are not really making much progress"
},
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"text": " That's my view. I mean, they're just kind of recycling the same old ideas, which haven't really led anywhere. The reason I lost confidence in Hawking's proposal is it gave the wrong predictions. Hawking's proposal did not produce a universe like ours, whereas our mirror hypothesis does. Our mirror hypothesis predicts a flat, spatially flat universe, homogeneous and isotropic,"
},
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"start_time": 960.128,
"text": " which looks like ours so i would say it's just an alternative to hawking just like hawking we have no extra input you see i what what i think doesn't really make sense philosophically or at least i shouldn't say philosophically maybe it does make sense philosophically to have a creator but uh what doesn't make"
},
{
"end_time": 1011.391,
"index": 36,
"start_time": 983.456,
"text": " What is not very appealing, let's put it that way, scientifically, if I want a predictive theory, I do not want the freedom to input stuff at the Big Bang. I want everything to be self-contained. I'm going to write down some laws of physics and I want those laws to define their own starting point. So usually laws are seen as distinct from boundary conditions. Exactly."
},
{
"end_time": 1037.841,
"index": 37,
"start_time": 1011.749,
"text": " So Hawking's hypothesis, the no boundary proposal, had the laws of physics, namely Einstein's theory of gravity, define its own starting point. That was what was so elegant about it. The mirror hypothesis is the same. You say the laws of physics and the CPT hypothesis that the universe doesn't violate CPT, those define the boundary condition."
},
{
"end_time": 1065.623,
"index": 38,
"start_time": 1038.541,
"text": " Yes. Now, how do you explain that our universe isn't conformally invariant?"
},
{
"end_time": 1093.797,
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"start_time": 1065.947,
"text": " so right great question around you and it's not so there must be something breaking it yes absolutely so um in order to resolve the big bang singularity you need this conformal symmetry right i mean that seems very intuitive if space shrinks to nothing the only way to make sense of that is if that is just an artifact of your description you've somehow used variables which shrink to nothing"
},
{
"end_time": 1122.312,
"index": 40,
"start_time": 1094.548,
"text": " You can map the problem to another problem in which space doesn't shrink to nothing, shrinks to a finite mirror, and now you have a coherent description where all the equations work and so on. So it seems that, at least from our point of view, you have to have conformal symmetry to have a sensible description of the Big Bang. That does not mean you need conformal symmetry today."
},
{
"end_time": 1151.681,
"index": 41,
"start_time": 1123.097,
"text": " Because between the Big Bang and today, you can break conformal symmetry. Okay, so this theory, so there needs to be a theory of conformal symmetry breaking. Now we're very familiar with this in the Standard Model. In the Standard Model, there's a symmetry group called SU2-whee, which rotates neutrinos into, neutrino into the electron, for example. It's an SU2 symmetry and the laws of physics have that as a fundamental symmetry."
},
{
"end_time": 1176.92,
"index": 42,
"start_time": 1152.363,
"text": " Nevertheless, that is what we call spontaneously broken by the Higgs field. When the Higgs field switches on, it sort of picks a direction in this SU2 symmetry space, which defines the electron and the neutrino. An electron is the direction along the Higgs field, neutrino is the orthogonal direction. And so the"
},
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"end_time": 1204.923,
"index": 43,
"start_time": 1177.466,
"text": " notion that the laws of physics do have conformal symmetry but that symmetry gets spontaneously broken. This is an extremely attractive hypothesis. Having said that, physicists have been working for 50 years on various ways to break the conformal symmetry. I can put it a different way. You see, the standard model"
},
{
"end_time": 1231.459,
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"start_time": 1205.913,
"text": " If I switch off the Higgs mass, there's one parameter in the standard model which breaks conformal symmetry. Only one. And that's the mass of the Higgs field. Right. It's the only parameter with dimensions of mass. Okay. And it's how you get the mass of the Higgs field. Without that parameter, the rest of the theory is conformally invariant."
},
{
"end_time": 1262.108,
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"start_time": 1232.654,
"text": " That's actually a consequence of renormalizability. Renormalizability is a very special property in four-dimensional theories and it requires dimensionless couplings and when you have dimensionless couplings you have conformal symmetry. So if you want to explain the breaking of conformal symmetry is actually explaining"
},
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"end_time": 1288.985,
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"start_time": 1262.927,
"text": " the origin of the Higgs mass. These things are very tightly related. What is very exciting, I didn't mention it in my talk, but there's a new development, very new development, which is a new idea for explaining the Higgs mechanism without inputting the Higgs mass. Okay. Okay. And this is"
},
{
"end_time": 1316.084,
"index": 47,
"start_time": 1290.009,
"text": " This is a, he's essentially a quantum field theorist who works in lattice gauge theory and also high temperature nuclear matter. So a real physicist, it's not a string theorist, and he has pointed out, you see, yeah, I need to explain a little bit more. How do we explain the origin of mass, okay, and mass scales?"
},
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"end_time": 1345.486,
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"start_time": 1316.886,
"text": " Now, in one case, in quantum chromodynamics, the explanation is very natural. Why do I say that? You see, quantum chromodynamics, the theory of a strong force, is what's called asymptotically free. It means that as you go to higher energies, the coupling constant goes to zero. As you come down in energy, the coupling diverges."
},
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"text": " And the theory becomes strongly coupled. You can say the following. Let's imagine I fix the strong coupling constant to some number like one thirtieth. That that's what you get by extrapolation at the Planck scale. And I now so the very, very high energies at the Planck scale. And I now ask, what is the scale at which it becomes one? So it's a thirtieth at the Planck scale."
},
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"text": " And ask what energy scale does it become one? And that energy scale is the scale of the mass of the proton. OK, so in other words, the proton mass is only one GV, whereas the pipe mass is 10 to the 19 GV. But that difference is not hard to explain. The reason it's not hard to explain is because the coupling constant runs only logarithmically with energy."
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"index": 51,
"start_time": 1400.811,
"text": " And log of 10 to the 19 is only about, what, 40 or something, 35 or 40. And so logarithmic running of couplings gives you a very natural explanation of enormous mass hierarchies. So in the case of QCD and the mass of a nucleon, the mass of the proton,"
},
{
"end_time": 1456.92,
"index": 52,
"start_time": 1429.821,
"text": " There isn't a fine tuning problem. You just say, okay, this for some reason, the coupling constant, the alpha three, the fine structure constant for the strong interaction is about a 30th at the point scale. When I come down in energy scale, when I hit one GV, it's wrong. And that defines the mass of the bound states of particles, the proton. So this new explanation of the Higgs mechanism is like that."
},
{
"end_time": 1485.128,
"index": 53,
"start_time": 1457.363,
"text": " It claims that there's a way to formulate the theory where there's no mass scale put in. All the mass comes about because of the running of coupling constants with energy scale, which is a quantum effect. So another way of saying is that all masses are quantum in origin. And so this new work shows that"
},
{
"end_time": 1511.561,
"index": 54,
"start_time": 1486.152,
"text": " claims to show that it's not quite complete. He hasn't actually predicted all the details. He's just made it plausible that it can work. It shows that the Higgs mechanism and the Higgs mass can be explained very naturally as being due to quantum effects in a certain kind of model. That kind of model"
},
{
"end_time": 1540.23,
"index": 55,
"start_time": 1512.21,
"text": " Is probably the simplest quantum field theory you can define. It's called lambda fighting force theory. And what I've shown recently is that model maps perfectly to our dimension zero scalars. What do you mean it maps perfectly to them? Well, it's quite technical, but so I'll just say a few words. They may not. Sure. You can also say what the name of the paper is so I could put that on screen. This is not written up yet."
},
{
"end_time": 1566.596,
"index": 56,
"start_time": 1540.503,
"text": " i see okay this is in very recent work we haven't written this up so this was just last month when i was at perimeter sure give the cliff notes if you don't mind sure i mean it's still secret so yeah i think so my i don't want to say too much about it because my students are busy working on it and they need this uh they they need these papers of course of course okay so then how about this"
},
{
"end_time": 1593.558,
"index": 57,
"start_time": 1567.261,
"text": " Do you think the Higgs is a fundamental particle? In our explanation of the cancellation of the vacuum energy and the conformal anomalies, we cannot have a fundamental Higgs. Interesting. The Higgs field cannot. It is inconsistent. This cancellation mechanism says there are no fundamental Higgs."
},
{
"end_time": 1623.148,
"index": 58,
"start_time": 1594.309,
"text": " It also says we have to introduce 36 dimension zero fields. The logical inference from those two facts is somehow the Higgs field must be made of the 36 dimension zero fields. It must be a composite. Okay. And this recent work by Romache is very exciting because it points to that being possible."
},
{
"end_time": 1651.271,
"index": 59,
"start_time": 1624.753,
"text": " So I think we are on the verge of a reformulation of the standard model based on dimension zero fields without mass parameter being needed to be stuck in by hand. This would automatically solve what's called the hierarchy problem. The hierarchy problem is the difference between the weak scale"
},
{
"end_time": 1673.951,
"index": 60,
"start_time": 1651.8,
"text": " Or the proton mass, if you like, in more simple terms, the difference between proton mass and the Planck mass. You know, they differ by 19 orders of magnitude. Where did that come from? This would be naturally explained if all mass scales arise in the same way due to the running of couplings, which is the quantum effect."
},
{
"end_time": 1700.452,
"index": 61,
"start_time": 1674.684,
"text": " So I think we're seeing hints of a solution of the hierarchy problem. By the way, the hierarchy problem was the main motivation for looking at supersymmetry. You know, much less compelling picture with all kinds of extra particles and parameters and assumptions. And so supersymmetry became big precisely because people thought it might solve the hierarchy problem."
},
{
"end_time": 1727.807,
"index": 62,
"start_time": 1701.237,
"text": " What we're seeing now is a far more economical solution which basically involves sort of tampering with the vacuum in quantum field theory using these funny dimension zero fields but you know if we're right this is going to revolutionize particle physics. You mentioned that you're not a fan of data fitting. Yes."
},
{
"end_time": 1755.828,
"index": 63,
"start_time": 1728.439,
"text": " And then you also mentioned that there's the introduction of these 36 fields. Right. So do you see that as a form of data fitting? No. What happens is, I mean, it's a very curious numerology that when I say there are 36 fields, we have to explain the number 36. We don't yet have an explanation for it. So what we found is the strange coincidence"
},
{
"end_time": 1785.725,
"index": 64,
"start_time": 1756.425,
"text": " That basically the vacuum energy per mode of the fields in the vacuum. So every quantum field in the standard model has an infinite number of modes. You can think about these as waves of different wavelengths in the different direction. So there are infinite number of these modes. Every mode has some vacuum oscillation and contributes some energy. So in the standard model, the energy in the vacuum is just basically some"
},
{
"end_time": 1812.244,
"index": 65,
"start_time": 1786.186,
"text": " overall number times a sum of integers. You know, I get some number times the number of spin zero fields, another number times the number of spin half fields, and then the spin one fields. Similarly, with the violations of local conformal symmetry, which I mentioned, this is called the conformal anomaly"
},
{
"end_time": 1842.483,
"index": 66,
"start_time": 1813.865,
"text": " it's also a sum of integers with strange coefficients okay so all of that is a consequence of quantum field theory that these if you put all the they're actually three of these kind of violations which happen and they're all sums of integers so you get three sums of integers with various coefficients including some fractions and you want all three sums to be zero"
},
{
"end_time": 1872.654,
"index": 67,
"start_time": 1843.49,
"text": " We discovered that if we add these strange dimension zero fields, and if we add precisely 36 of them, then all three anomalies cancel the vacuum energy and two independent contributions to these violations of the local scale symmetry. So suddenly we get this much more beautiful theory. It demands 36. I know three parameters, right? It requires 36."
},
{
"end_time": 1901.271,
"index": 68,
"start_time": 1873.046,
"text": " Now, where did the 36 come from? There are various suggestions as to where it comes from. 36 is the dimension of a group, in fact two groups, simple groups. One is sp8 and the other is s09. These groups are related to twister theory. Twister theory has a sort of bigger version which involves sp8"
},
{
"end_time": 1931.305,
"index": 69,
"start_time": 1901.954,
"text": " And what's very tantalizing is that maybe, you know, once we understand that connection better, we'll see that we're forced to 36. Preferably by gravity. We want to see that gravity, as gravity does look much nicer in twister, its twister representation, there are no new parameters in the twister representation. The twister representation may then lead us to this bigger"
},
{
"end_time": 1961.032,
"index": 70,
"start_time": 1932.159,
"text": " picture in which there are 36 fields. Coincidentally, I should have mentioned, twister theorists who are much more on the mathematical end than we are, have shown that in the Feynman path integral for gravity, they need to introduce 36 dimension zero fields to make sure that the twister path integral"
},
{
"end_time": 1989.548,
"index": 71,
"start_time": 1961.323,
"text": " equals the gravitational path integral and the amazing thing about their result is it's not perturbative you see our result is only true for three fields it's the very it's the most naive possible calculation their result is true to all orders right these are serious mathematicians and they've shown that introducing these dimension zero fields cures these problems"
},
{
"end_time": 2015.572,
"index": 72,
"start_time": 1990.316,
"text": " non-perturbatively okay so that's very spectacular so we are hoping that our work ultimately connects with theirs if it does then you know the number is is actually going to be fixed it's not a free parameter so that's still to come now having said that the way we treat the 36 fields is we you know naively have i got 36 fields that have a huge number of parameters and coupling them all"
},
{
"end_time": 2040.623,
"index": 73,
"start_time": 2015.998,
"text": " You know, I could write down five, you know, let's say the kinetic term and then a potential term with 36 different fields that have a very huge number of parameter space of potentials. The way we use these fields, they are not allowed to have a potential. OK, so that's not possible. And the way we use them is we treat them all equally."
},
{
"end_time": 2069.258,
"index": 74,
"start_time": 2041.561,
"text": " So when they contribute it's 36 all giving exactly the same. That's, as I said, there are assumptions in our calculation. We always make the simplest assumption and that assumption is that all 36 fields contribute equally. So we've tried to be as minimal as possible with this theory. It doesn't mean that, you know, that there aren't three parameters for sure because this is still under construction."
},
{
"end_time": 2094.377,
"index": 75,
"start_time": 2069.821,
"text": " Uh, what we hope is that as we understand it more and more deeply, we will see that, you know, there are constraints which come in, which, which force you to make these choices. And, uh, you know, we're hoping that ultimately there, there aren't any, uh, free parameters, uh, in the, in this game, of course, that's a very ambitious dream. Um, yes, right."
},
{
"end_time": 2124.002,
"index": 76,
"start_time": 2094.633,
"text": " So this is the Boyle-Turrock model, correct? Yes. That's what people can search if they want to hear more. Yes. They can just look for my name, Latha Boyle's name, and all of our papers on the archive. So the 36. Yes. There are also 36 parameters in the gravity spin connection. Correct. Is that a numerical coincidence? Other people have pointed this out that there are many formulations of Einstein's theory of gravity. The original one, you have a metric."
},
{
"end_time": 2153.251,
"index": 77,
"start_time": 2124.582,
"text": " with 10 components and then rather in a rather ugly way you have a Christoffel connection which has 40 components. Okay, so you have all these different fields in fact in own sense here of gravity. Now what happened after that is other people discovered different formulations of gravity which are somehow more economical and more beautiful, more geometrical and there are many of these"
},
{
"end_time": 2181.937,
"index": 78,
"start_time": 2153.831,
"text": " one involves fear binds and spin connections. And in fact, you have to go to that representation to describe fermions in gravity. You have to use fear binds and spin connections. But these things have different numbers of fields than Einstein's formulation. And these as you mentioned,"
},
{
"end_time": 2209.121,
"index": 79,
"start_time": 2182.159,
"text": " There's a particular formulation of of gravity called a plebansky formulation which emphasized that you could write down Einstein's equations very very beautifully if your fundamental object was not the metric metric but was an anti-symmetric two-component tensor called a B field and this B field is"
},
{
"end_time": 2235.418,
"index": 80,
"start_time": 2209.531,
"text": " So an anti-symmetric tensor with four, so two indexes, each one can run over four values, has six values. This knee field has both space time indices, both a mu, a new index, a sort of coordinate indices, and also Lorentz indices, also anti-symmetric. And so the six of one and six of the other, and you get 36. So"
},
{
"end_time": 2265.009,
"index": 81,
"start_time": 2235.879,
"text": " People have pointed out that maybe the 36 is somehow telling us about this formulation of gravity. That's very tantalizing. We don't know whether that's true. I think the connection with twisters is also a hint that that may be a better formulation of gravity. So, you know, we're trying to do something very difficult here, which is write out a consistent"
},
{
"end_time": 2295.145,
"index": 82,
"start_time": 2265.742,
"text": " you know, quantum path integral for gravity. And certainly the naive one is not the full story. So we have to find the right variables in which to write that path integral for gravity. And as I say, there are a couple of hints that 36 is going in that direction. But so far, these are just kind of numerical coincidences."
},
{
"end_time": 2325.213,
"index": 83,
"start_time": 2295.538,
"text": " Where does dark energy come from? Well, it's a good question. I mean, as you know, as I said in the talk, it's the simplest form of energy there is. It's just uniform in space, uniform in time. So you view it as another constant, another knob to fiddle with? I am not happy about that, but that is the current state of thing. In the part of my talk I didn't give,"
},
{
"end_time": 2350.913,
"index": 84,
"start_time": 2325.589,
"text": " I was going to talk about thermodynamics and the thermodynamics of the universe. You see, I think the most profound explanations in physics are ones which use thermodynamics. Entropy. Entropy is the most profound concept in physics. It's like how many ways can you arrange something, right?"
},
{
"end_time": 2381.015,
"index": 85,
"start_time": 2351.51,
"text": " More generally you can say entropy tells you, you know, if I have limited information about the world and I want to know what's going on in the world, what I do is maximize the entropy. I say what are the greatest number of microstates of the world compatible with what I do know and then most likely the world will be"
},
{
"end_time": 2410.623,
"index": 86,
"start_time": 2382.517,
"text": " in one of those states which maximizes the entropy, right? The most likely states are the most numerous. So the notion of entropy I think is sort of beyond the laws of physics. It's saying given probabilities, given that nature is probabilistic and we think quantum mechanics is probabilistic, given that the laws of physics are fundamentally probabilistic, the laws of probability kind of"
},
{
"end_time": 2439.445,
"index": 87,
"start_time": 2411.425,
"text": " supersede everything else and so thermodynamic explanations are always the best ones because basically they say no matter what you do with the laws of physics you're going to get the same answer okay so we have a new thermodynamic explanation for the geometry of the universe you based on hawking's ideas and our mirror boundary condition etc etc but it is"
},
{
"end_time": 2462.483,
"index": 88,
"start_time": 2440.111,
"text": " What about lambda? So what is lambda? What is the cosmological constant? Now in thermodynamics, the basic idea is you constrain certain quantities. So let's say I've got a box of gas, certain number of particles, certain amount of energy, and I find the maximum entropy state."
},
{
"end_time": 2491.903,
"index": 89,
"start_time": 2463.268,
"text": " Which is the equilibrium one, you know, where all the particles are essentially evenly distributed and they've shared out all the energy and so on But you need to impose the right constraints So in the case of particles in a box, it would be the number all the conserved quantities number of particles total amount of energy Actually the total momentum of the particles the total angular momentum. You can constrain those things now in"
},
{
"end_time": 2518.677,
"index": 90,
"start_time": 2493.131,
"text": " Gravity, everything is geometrical, okay, and that makes the theory very unique. You say, you know, how do I define the theory? Well, I have to deal with geometrical quantities. Probably the most obvious geometrical quantity you can think of in a four-dimensional space-time is the volume, the total volume of the space-time."
},
{
"end_time": 2548.626,
"index": 91,
"start_time": 2519.326,
"text": " Right. I integrate over space and time and I get a four volume. So now you ask, what is the cosmological constant? Well, it is the term in the action for gravity, which multiplies the full volume. So lambda multiplies the full volume. If I do thermodynamics on gravity, lambda is analogous to temperature or chemical potential. You know, what is temperature?"
},
{
"end_time": 2578.387,
"index": 92,
"start_time": 2548.933,
"text": " Temperature says when i do thermodynamics i take the energy in the system and i multiply it by one of the kt so i have in my Statistical ensemble i've got the boltzmann factor e to the minus energy of a kt the best way to think of temperature it is just One of the kt is the quantity multiplying the energy in the statistical ensemble And i just dial that to get the average energy in the box"
},
{
"end_time": 2605.333,
"index": 93,
"start_time": 2579.343,
"text": " so you can say you would dial the cosmological constant to get the full volume of the universe okay that's the way in which it occurs in in in gravity so essentially it's saying that you know um if i want to describe particles in a box i need a temperature i just say what if i tell you if i ask you what's the most likely configuration particles in a box"
},
{
"end_time": 2631.237,
"index": 94,
"start_time": 2605.981,
"text": " And I don't tell you the energy and I don't tell you the number of particles. You can't say anything. You need some information. Yes. So I can say a box of gas at temperature, you know, 30 degrees centigrade and with a certain density of particles, you know, a certain number of particles in the box. Then I've defined it. So it appears the way the cosmological constant enters physics"
},
{
"end_time": 2661.425,
"index": 95,
"start_time": 2631.544,
"text": " Is in the same way as temperature does or chemical potential which we use to describe the number of particles And it controls the volume of the universe now then it's up to you what you fix and what you predict So you can fix the number of particles or I could say no. I've got a box of gas at certain pressure Pressure and temperature, you know some measurable things"
},
{
"end_time": 2689.326,
"index": 96,
"start_time": 2662.125,
"text": " Then predict how many particles there are. Predict the energy in the box. But you need to know a certain number of things to predict other things. Lambda might be just one of those things you need to know to predict other things. When we calculate the entropy of cosmology, it's very tantalizing. We find that the entropy is greater"
},
{
"end_time": 2714.838,
"index": 97,
"start_time": 2690.213,
"text": " The smaller lambda is, and the thermodynamics only make sense if lambda is positive. So basically, roughly speaking, it predicts that the cosmological constant is as small as it can be, but it has to be positive. And that's very compatible with what we see. But it's only halfway there. You know, we need to now understand what are the other constraints"
},
{
"end_time": 2743.166,
"index": 98,
"start_time": 2716.049,
"text": " Should we be fixing lambda? Should we be fixing the full volume? Maybe the full volume is quantized. You know, we haven't put that in yet. When you quantize the full volume, maybe lambda only takes discrete values. So I think we're seeing glimpses of the role of lambda, but at the moment we don't really understand what it is."
},
{
"end_time": 2772.978,
"index": 99,
"start_time": 2743.746,
"text": " Or how to use it. We can fit it to the universe. That's not a theory. That's just a fit. Um, but what you hope is a sort of deeper understanding will lead you to understand the value. But ultimately, you know, the value. So this may sound a little anthropic and I'm not anthrop. I don't like the anthropic principle because I essentially, I think it's very abused. Um, but I'm not averse to"
},
{
"end_time": 2801.715,
"index": 100,
"start_time": 2773.353,
"text": " selection effects. There are selection effects. You know, we live on the surface of a habitable planet. That's not a surprise. That's where we evolved, you know. And so it sort of seems foolish given that there are, you know, 100 billion stars and 100 billion galaxies and 100 billion stars in each galaxy."
},
{
"end_time": 2831.937,
"index": 101,
"start_time": 2802.978,
"text": " We don't usually say, you know, predict why the Earth is habitable. I mean, we're here because it's habitable. So that's fine, but you shouldn't... You see, when people use the anthropic principle in cosmology, I think they do it in"
},
{
"end_time": 2858.387,
"index": 102,
"start_time": 2832.602,
"text": " What yeah technically you say that they don't know what the measure is they don't know how much weight to assign any particular cosmos and then what they typically do is say oh this this one looks like the one we see the universe had to be like the one we see because we're here okay and so maybe it has to be like that just because we're here"
},
{
"end_time": 2871.971,
"index": 103,
"start_time": 2859.923,
"text": " And that gets them off the hook as actually explaining anything at all. But I don't want to do that. I want to understand as much as we can about the universe with as few assumptions as possible."
},
{
"end_time": 2900.742,
"index": 104,
"start_time": 2872.346,
"text": " So I don't mind there being a selection effect at some point. Yeah, I'm not understanding the difference between the selection effect and then what the people who have a variety of values and then they say that, well, we happen to find ourselves at one of these values. Right. And it's because that value is small. I don't see the difference. Imagine you imagine you have multiverse. Sorry, is it the case that in the planet case we have a measure? Yes, because we can see how many other habitable stars there are habitable planets surrounding a star there? No, no."
},
{
"end_time": 2930.35,
"index": 105,
"start_time": 2902.125,
"text": " In the planet case, we have not seen any other, so far, any other planet that's remotely habitable. Maybe there's some recently. But in the planet case, we have observations indicating that it's really unusual for life to arise. I mean, certainly it seems there's no other life in the solar system."
},
{
"end_time": 2960.623,
"index": 106,
"start_time": 2930.947,
"text": " and when we when we look at other stars and planetary systems typically they seem not to be suitable for at least our kind of life so it it seems that life is rare right and maybe very very rare for all we know we're unique in in in the observable universe now what people do in the"
},
{
"end_time": 2983.882,
"index": 107,
"start_time": 2961.288,
"text": " Much much further. And say, you know, I've got this 10 to the 1000 universes in string theory. Maybe only universes like ours are habitable. And, and therefore, all the features that I can't explain of our universe using string theory, I'm going to explain this way."
},
{
"end_time": 3008.626,
"index": 108,
"start_time": 2984.787,
"text": " so basically it's just an excuse it's a way of letting yourself off the hook that you will never explain the value of the cosmological constant you will never explain you know various other cosmological parameters just because you're saying oh there had to be that way because otherwise we wouldn't be here so i think that's a non-explanation i see what i what what i believe there may be"
},
{
"end_time": 3027.073,
"index": 109,
"start_time": 3009.309,
"text": " I think all the indications are there may be an explanation which is way better than that, which basically says that in a certain category of, well let's see,"
},
{
"end_time": 3055.469,
"index": 110,
"start_time": 3027.671,
"text": " you see okay now i'm going to get very spacey and refer to bernardo bring it on so bernardo said yeah bernardo says that you know reality is essentially a manifestation of consciousness right and and that the world at a deep level is all about information and this consciousness unified"
},
{
"end_time": 3085.401,
"index": 111,
"start_time": 3055.759,
"text": " Somehow processes this information, right? So I think that's a very appealing perspective It's not very materialistic And as he rightly said it's not very scientific because at this point we don't know how to test it But we can't disprove it either So now if you adopt this perspective and you say within this realm, however consciousness works"
},
{
"end_time": 3115.964,
"index": 112,
"start_time": 3086.442,
"text": " You know, it is possible for things like universes to emerge. If the laws of physics are quantum mechanical, or actually just probabilistic, there will be a number of possibilities, you know, and given that I, my, what did he call it, my dissociated, I'm quoting his words, given that my dissociated consciousness"
},
{
"end_time": 3143.558,
"index": 113,
"start_time": 3117.176,
"text": " right, has only partial awareness. You know, maybe universes like the one we see are the most probable. Now, how do we even test this? How do we try to turn this into science? I would say the best way we do it is by taking the laws of physics we know,"
},
{
"end_time": 3172.073,
"index": 114,
"start_time": 3144.514,
"text": " Use analogies, use mathematics, try to make a logical framework where we calculate probabilities. And our calculations of entropy and gravitational entropy are very much going in this direction. It may be that in this space of information processed by consciousness, you know, certain values are preferred, most likely."
},
{
"end_time": 3200.896,
"index": 115,
"start_time": 3173.046,
"text": " If it is a thermodynamic explanation, that will be fairly independent of the laws of physics. You know, maybe it probably will depend on gravity in some way, but not on the fine details. And I think it may be that we can at least approach such an explanation of the cosmological constant of the basic structure of spacetime. And that seems to me a very fruitful"
},
{
"end_time": 3231.391,
"index": 116,
"start_time": 3201.544,
"text": " way of exploring you know so instead of posing the question like i've measured this number lambda it's 10 to the minus 20 and 120 in plank units you know okay what a massive puzzle that is you know don't try to just predict the number try to predict everything and use all the information we have try to make your framework compatible with everything we see and as you succeed in refining and further and further formalizing"
},
{
"end_time": 3256.237,
"index": 117,
"start_time": 3231.834,
"text": " the laws the unified laws of physics with all the observations we have as you succeed in doing that if nature is unified you will see these unifications happen so maybe we're right maybe we have explained the fluctuations coming out of the big bang that's great now that gives us confidence in the vacuum"
},
{
"end_time": 3284.343,
"index": 118,
"start_time": 3257.005,
"text": " Right? How do we understand lambda? Well, lambda is of energy in the vacuum, right? That's what lambda is. We've made a step forward to it because we've cancelled infinity. You know, we had a terrible paradox that the vacuum energy was infinite. In our new theory with these dimension zero fields, at least the leading infinity is cancelled. Now we're dealing with finite numbers. So let's just keep developing that. Keep developing the machinery and the formalism"
},
{
"end_time": 3310.981,
"index": 119,
"start_time": 3285.145,
"text": " trying to remove kind of logical inconsistencies as we go and maybe this will actually end up converging on the lambda. If lambda currently in our current perspective takes this ridiculously small value right but as I explained if things only depend logarithmically on energy scale you can get very large numbers appearing out of very modest numbers"
},
{
"end_time": 3339.514,
"index": 120,
"start_time": 3311.323,
"text": " You know, equivalently, you can say if I exponentiate 30, I get a huge number. Right. But it's only because you didn't understand the logarithm that you thought this is ridiculous. So we do know many things in physics change logarithmically, most likely, you know, the law, most likely the log of lambda is the physical is the physical parameter."
},
{
"end_time": 3366.578,
"index": 121,
"start_time": 3339.906,
"text": " And if the log is a physical parameter, then there's no real puzzle about it being so tiny. And perhaps the log had to take a particular value in order for the physics to be consistent. So I wouldn't claim we are near to explaining why lambda is so small. What I would say is we're developing a framework which is unified"
},
{
"end_time": 3392.944,
"index": 122,
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"text": " In so far as it goes, it is complete. It accounts for everything we see. It accounts for all the known laws of physics. And yeah, let's push it further. I wish there were many other frameworks like ours competing. You know, that's healthy science. What I fear at the moment is that string theorists have essentially gone off into mathematical land, mathematics land,"
},
{
"end_time": 3422.415,
"index": 123,
"start_time": 3393.473,
"text": " And they're busy exploring N equals four super young males and, you know, all kinds of, um, ADS five cross S five, you know, all of sort of totally unrealistic universes. Um, and yeah, they, what I worry about is they are never to return. When you take, you take one wrong turning in theory land and you probably, and if you're dogmatic, you will never come back."
},
{
"end_time": 3453.217,
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"text": " And that's the biggest danger in the whole field of theoretical physics is you make one mistake. I mean, it's so ambitious, you know, to explain everything that you make one mistake. If you insist on sticking to that mistake, you're never going to come back to the right picture. So I think much more likely to me is is if you are adaptable. If you quickly realize when you've gone wrong,"
},
{
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"text": " Neil, I appreciate you spending so much time with myself, with the audience here and"
},
{
"end_time": 3500.265,
"index": 126,
"start_time": 3473.302,
"text": " I appreciate you being the inaugural talk on the rethinking the foundations of physics. What is unifications series? Thank you. And people who don't know what that is, there's a talk that you can go click on that gives a lecture that Neil just gave approximately one hour in length. And it's a fantastic talk that goes over the mysteries of the universe explained economically in a simple manner. So thank you. Thank you. You're very kind. Thanks a lot. It's an absolute pleasure."
},
{
"end_time": 3516.22,
"index": 127,
"start_time": 3501.135,
"text": " Firstly, thank you for watching, thank you for listening. There's now a website, curtjymongle.org and that has a mailing list. The reason being that large platforms like YouTube, like Patreon, they can disable you for whatever reason, whenever they like."
},
{
"end_time": 3542.551,
"index": 128,
"start_time": 3516.22,
"text": " That's just part of the terms of service. Now, a direct mailing list ensures that I have an untrammeled communication with you. Plus, soon I'll be releasing a one-page PDF of my top 10 toes. It's not as Quentin Tarantino as it sounds like. Secondly, if you haven't subscribed or clicked that like button, now is the time to do so. Why? Because each subscribe, each like helps YouTube push this content to more people like yourself"
},
{
"end_time": 3560.009,
"index": 129,
"start_time": 3542.551,
"text": " Plus, it helps out Kurt directly, aka me. I also found out last year that external links count plenty toward the algorithm, which means that whenever you share on Twitter, say on Facebook or even on Reddit, etc., it shows YouTube. Hey, people are talking about this content outside of YouTube."
},
{
"end_time": 3589.292,
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"text": " which in turn greatly aids the distribution on YouTube. Thirdly, there's a remarkably active discord and subreddit for theories of everything where people explicate toes, they disagree respectfully about theories and build as a community our own toe. Links to both are in the description. Fourthly, you should know this podcast is on iTunes. It's on Spotify. It's on all of the audio platforms. All you have to do is type in theories of everything and you'll find it. Personally, I gained from rewatching lectures and podcasts."
},
{
"end_time": 3613.507,
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"text": " I also read in the comments"
},
{
"end_time": 3639.275,
"index": 132,
"start_time": 3613.507,
"text": " There's also just joining on YouTube. Again, keep in mind it's support from the sponsors and you that allow me to work on toe full time. You also get early access to ad free episodes, whether it's audio or video. It's audio in the case of Patreon video in the case of YouTube. For instance, this episode that you're listening to right now was released a few days earlier. Every dollar helps far more than you think. Either way, your viewership is generosity enough. Thank you so much."
},
{
"end_time": 3668.507,
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"start_time": 3652.022,
"text": " Think Verizon, the best 5G network is expensive? Think again. Bring in your AT&T or T-Mobile bill to a Verizon store today and we'll give you a better deal. Now what to do with your unwanted bills? Ever seen an origami version of the Miami Bull? Jokes aside, Verizon has the most ways to save on phones and plans where you can get a single"
},
{
"end_time": 3682.108,
"index": 134,
"start_time": 3670.64,
"text": " And we'll give you a better deal."
}
]
}No transcript available.