Nobel laureate Professor Gerard 't Hooft proposes that quantum mechanics is fundamentally a deterministic theory, not probabilistic, and that our perception of randomness stems from our ignorance of underlying, discrete "cellular automata" rules governing reality.
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"Quantum mechanics' predictions are totally wrong." Picture reality as a cosmic pinball
machine. Every ball follows a deterministic path, no exceptions. To Nobel laureate Professor
Gerard 't Hooft, the fact that we can't track all these balls is why we invented quantum mechanics,
effectively to handle our ignorance. This is quite a startling proposal, especially from
the winner of the Nobel Prize in 1999 for his work on the electroweak interaction. To the professor,
there are no real numbers, there's no superposition, not even wave functions,
fundamentally. Instead, there are these discrete cellular automata, updating in quantized steps.
Today, we discuss why he thinks standard physics has it backward, particles don't exist in multiple
states, Cats aren't simultaneously dead and alive. The universe never plays dice.
I'm Curt Jaimungal, and in this conversation, we tackle super-determinism,
why seemingly absurd theories get more support than, ostensibly, realistic ones,
and how recognizing space-time quantum clones solves the problems of black holes.
Professor, when we were speaking off-air, you mentioned to me that “the crazier
the proposal, the easier it is to get accepted.” What did you mean by that?
Well, it happens very often, rather surprisingly. If you come with a very simple theory or idea,
then people have all sorts of complaints and objections. When you come to something which
clearly cannot be corrected entirely, and sounds like a really long-distance approach,
then that gets much more support in general. For example, I first encountered that when
I was in heavy discussions with my advisor, Veltman, about renormalization. And we agreed
there was still one very important problem to be handled, which was, can it all be done
consistently? The equations that we have are not contradicting each other. And I searched
very hard and I had the idea of adding a fifth dimension to space and time. And it worked,
but then it only worked for one-loop diagrams and then it went wrong. So eventually I said,
well, maybe if I take 3.99 dimensions or 4.01, then everything is formally finite and calculable
and there are no contradictions. So all I have to do is take a limit and the number of space
dimensions goes to 4. But then I thought how am I going to explain that to Veltman? Because
he's very critical. So now I said, well, I have this idea about changing the number
of dimensions of space not by an integer but by a small fractional number. And much to my surprise,
he got immediately enthusiastic right away. And that was for other colleagues as well.
They immediately accept such a wild idea, which I thought was rather crazy.
Whereas in contrast, if you talk about quantum mechanics, and you suggest maybe
quantum mechanics is just a deterministic theory in disguise, in disguise because there's so much
going on in this universe, you can't really check whether it's deterministic or not. But I thought
this was a very natural sort of zero attitude you would have towards quantum mechanics. But again,
then people come with lots of objections. But when you propose to someone that there
are two or many universes at the same time, some more real than the other, but they're all real,
different realities, I find that total nonsense. I can't understand how that
works. But very rarely you hear objections against that. You hear only alternatives,
which are equally crazy. But the idea that the world is just completely deterministic,
simple-minded, just like grains of sand, if you play around in a bucket of sand,
then that would be the easiest thing to assume. But then people come with all sorts of objections.
So why do you think that is? Do you think it's because our validation criteria is off? Or do
you think it's because the more fantastic idea, the more it appeals to people? Or
is it the more fantastic idea, the more difficult it is to find an error with it?
Yes, I think it is that with more fantastic ideas, you can make noise, you can shout that we are now
a fantastically crazy idea, and it works, or maybe it works to some point, but it seems to work. And
then you're a hero, whereas if you propose something very basic, something very mundane,
something very ordinary, then they say, “Yeah, yeah, we had that, and we don't believe that.
It's something more complicated.” Aha. So this is a general attitude you find among people.
Now, you've also expressed some frustration with quantum
physicists in terms of blind spots. You just alluded to it, so regarding
interpretations of quantum mechanics. Let's flesh that out some more, please.
Yes. Well, the important point is that quantum mechanics only gives statistical answers to any
questions as to what will happen when you make such an experiment. And you directly
get the statistical answer which is part of the world of possible answers that seems reasonable.
And so quantum mechanics gives you the correct probabilistic predictions. But the real world
is not probabilistic. It's only probabilistic if you don't have all information to be sure
that this book is there and that book is there. No, if you just open the cupboard,
you find all books falling on the floor. And you can't predict how they will fall on the
floor except to make kind of predictions, just as in quantum mechanics, where you say, “No, no,
we don't know where this book is going, we don't know where that book is going,
but we just know the probability that something happens.” And this you can calculate,
and this you can check against experiment. Do we get wide deviations from the probabilities
predicted by quantum mechanics? So, in that sense, the theory is right, but the theory
gives completely wrong predictions as to say, well, where now exactly will everything come?
Quantum mechanics can only give statistical predictions, and I think those predictions
are totally wrong, but they are closer to the truth than anything else you can predict. So, and
they're close to the truth because in many cases you cannot make any better predictions. Think of
an insurance company. The insurance company is not interested in exactly where and when you made your
accident. The insurance company will just want to know how many cars are there, how many people
are driving these cars, how many have alcohol in their blood, how many have done this, how many
have done that. So, they want a statistical answer. They don't want the explicit answers.
So I think in the world of science, also, quantum mechanics will give you the statistical answers
and not the true answers. But to me, that means that the theory is incorrect.
We should basically have a theory which, if you start with a situation where every single
particle, every single atom, every single photon is exactly localized the way where it should be,
or having the probabilities (or properties?) that it should have without any doubt,
any uncertainty. Then the theory should predict explicitly where every single particle is going.
Now we don't have such a theory, and quantum mechanics is not such a theory. But eventually
what I want is to have a theory that gives this kind of predictions. If you knew all the
initial data with infinite accuracy, with mathematical precision, then the theory
gives you an explicit result that every single particle will only collide in one particular way,
and all the others are simply not happening. So that is the theory I want for quantum mechanics,
even though I know very well that nobody will ever be able to use that property in practice.
In practice we don't know the initial states so accurately that we don't know how particles will
collide, so any answer will be as good as any other. But then quantum mechanics is a perfect,
ingenious theory that gives you exactly the right probabilities,
which is what we want in practice anyway. So for practical use, it's not so meaningful to
search for a theory that predicts everything with infinite prediction. But for me, searching for
what such a theory looks like will give me some idea about the ultimate truth, a theory that,
like quantum mechanics, gives you very precise probabilities. But if you knew the initial state,
it would be infinitely precise. Such a theory has my strong preference, even if we don't even know
how to start building such a theory. And that's the peculiar situation right now, that even if you
wanted a deterministic theory, it is very hard to design it just from scratch. We don't know enough.
So, when you say quantum theory is quote-unquote “totally wrong,” I'm sure,
firstly, some people may be thinking hidden variables. Is that what this professor is
arguing for? Hidden variables have been disproved. We can get to your
cellular automata approach shortly. But why would you say that it's totally wrong?
Because the counter-argument is that it's considerably precise in its predictions,
and it's been verified to more digits than anything else in any other field of our knowledge.
But what is wrong is that the theory doesn't ever talk about generally existing situations,
which I have a probability 1 of happening and probability 0 of not happening,
or any other situation is probability 0. Think of two particles in a beam like at
CERN. The two particles will hit each other. And suppose we knew exactly how these two particles,
how many of them will hit and how they will hit and so on. Then still, quantum mechanics
gives you a probabilistic outcome. Even though the initial state were precisely defined, then still
the theory gives you a statistical answer. And that, according to my intuition, cannot be right.
Okay, so the probability distribution is
not such that it's zero everywhere except at one place and gives 100%.
Yes, yes. I see. And by the way, you wanted to ask a question about hidden variables,
but what I'm talking about really is the hidden variable theory, or rather,
the philosophy of the hidden variable theory is exactly followed. Except when people try to
make computations with hidden variables, they don't follow its own philosophy,
and that's why they get contradictions which are worse than the contradictions
in quantum mechanics. So they say, “No, that cannot be right.”
Tell me about this. What's the distinction between hidden variables as people conceptualize it and
then the so-called philosophy of hidden variables? What is the philosophy of hidden variables?
Well, in principle, it agrees. That's why I call it the philosophy of the hidden variables. The
hidden variable itself obeys this philosophical intuition that it should be giving infinitely
precise predictions. The probabilistic outcome or distributions that we measure in our experiments
comes about because we don't know well enough how to do any calculations that will give you
more precise results. It's the same like when you, in the weather forecast, you predict there
will be clouds there, there will be rain there, but we cannot possibly predict where every single
raindrop will be falling, how exactly the clouds will be shaped, and so on. Of course,
we cannot do that. That's much too hard. But it doesn't mean that the meteorologist who makes this
prediction doesn't try to predict as accurately as he can what the shapes of the clouds will be
and so on. But as you know, of course, they're not far from getting very precise theories about that.
So there are, broadly speaking, two interpretations of the wave function.
One is called psiontic, and then another is called psie-epistemic. And for people
who have vaguely heard these terms, ontic refers to something existing in reality,
and then epistemic has to do with our knowledge of it. So, psiontic,
people who believe the wave function is real, tend to be Everettians, for instance. And then,
psi-epistemics, I assume you would qualify as such. And then the counterargument would be,
well, what about the PBR theorem? So, there are loopholes. Can you speak about these loopholes,
please? And also, I would love to know your view on many worlds.
It's basically the same that many is as untrue as the other theories of quantum
mechanics where we have several realities. But the many-worlds theory is the extreme logical
conclusion from this hidden variable, not from the hidden variable theory, but from the many-worlds
theory that every single outcome is possible with a certain quantum probability. I'm saying, well,
you would expect even a hidden deterministic theory to give such predictions because you
are not able to do every computation as accurately as you want. So even if you have a deterministic
theory, then still you would only be able to make statistical predictions. So you have to
take the complete world of all possible states that you're in your initial state.
The final state will also be a distribution of certain of infinitely many possibilities.
And your theory is better if these probability distributions look more similar to the reality.
So, yeah, that's the kind of theory which one could call hidden variable theories,
and I agree that that's basically the main idea, that there are variables that we cannot
identify exactly today, but which happen only with certainty, never with a distribution of,
a superposition of possibilities, but only single sharp states.
...Roger Penrose is also known for saying quantum theory is wrong. Note,
I also spoke to Roger Penrose about this very topic. Link in the description...
ROGER PENROSE: Quantum theory as a whole is wrong. It's not Einstein was wrong. Quantum
mechanics is wrong. I say this very blatantly because it's a blatant topic. I mean, Einstein
and Schrodinger were much more polite. They said it was incomplete. Incomplete means wrong.
CURT JAIMUNGAL: Well, you're telling it like it is.
ROGER PENROSE: We've got to change it, so it's wrong!
(back to Gerard 't Hooft podcast) ...And I'm curious, given that you're both Nobel
Prize winners who believe quantum theory is incomplete, which is how I would characterize it,
just so you know, have you ever had a conversation with Penrose about this?
Yes, but very often I disagree with him, and there are basic issues. But his formulation is a
bit vague as to what it exactly means, but he has many theories that I don't believe in. But my only
belief is that the ultimate theory of nature, whatever it looks like, has only variables,
like hidden variables, and everything that happens, happens with certainty. This happens,
that does not happen, but there's nothing in between. There's never a superposition
between a dead cat and a live cat, for instance. That's the famous example where you bring that
quantum mechanics to the extreme. No, I would think that we don't know what the theory will
predict whether the cat will die, whether the cat will survive. We don't know that. That's very,
very hard. But in principle, theory should predict whether the cat will be alive or not. And the
cat will not be in a superposition. That's only because our understanding today, the philosophy of
the true laws of nature is too uncertain and too imprecise to be able to do any better
than saying that the cat will have a certain probability of surviving this experiment. And
we can calculate even that probability, but we don't know how to do it better than that.
So, I know we spoke briefly off-air, and I want to reference something. This is a
quotation from you, I believe. I hope I wrote this down correctly. “My claim
is that if we ever hit the true equations, there will be no superposition any longer.”
Yes. So, this is what you're referring to.
That's what I'm saying, yes.
Okay, please expand on that. So,
why would it be that if you found the true equations, there would be no superposition?
your first question, you... I talked about how the more outlandish and zany the theory,
the more it's accepted, at least it's cognitively easy for a physicist to not find objections with
it. The thing that people now always put in doubt is, to me, the far most obvious
situation. I think that grains of sand are particles just like planets and stars, rocks,
or atoms or molecules. They're all particles and they all obey equations. And okay, the equation
of the molecules and atoms is a bit different, but basically it should be the same. That is
to say there are variables which determine what it will do next. But an atom or molecule is much more
complicated than what people think. It's not just that the molecule consists of so many atoms and
then they're in a wave function and that's it. No, they are not in a wave function. And there
are things there which I don't know even whether they are atoms or molecules, but something else.
And they only obey equations that lead to certain outcomes if you know the initial state
with infinite certainty. That holds for rocks, for sand, for atoms and molecules and elementary
particles and photons and neutrinos, you name it all, they're all only obeying deterministic laws.
I would find this the most obvious suspicion, because I can't prove it.
I can only say this is my favorite view of what the scientific world ultimately will be facing,
a theory of that nature. But I find it very difficult to imagine anything else
whereas all these people who come with these fantastic quantum stories they think they can
get away with much more complicated ideas without anybody questioning.
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We also spoke off-air about quantum mechanics as a language,
and I'm not sure what that meant. So maybe that's related to your newest approach.
You used the word epistemic. You used the word epistemic. It describes things,
and the wave function is epistemic. That's exactly what it is, I believe. It's because we haven't got
anything better than that wave function. So let's assume that wave function is a way to
describe the probability distributions that will come out of your experiment.
The real reason why you get probability distributions will be that we don't understand
and we don't have the initial state with infinite precision. Which is what you would need to get a
precise non-probabilistic answer, but just a certain answer as to what is happening.
Okay, so why don't we get to your cellular automata approach,
and why don't you walk us through how it was initially and then what it's evolved to now?
It didn't change very much. The original idea was that the world, although it looks like
a problem, it's a probabilistic world where notions of temperature and entropy are very
well defined, better defined than many of the deterministic notions of particles and
molecules. So the cellular automaton is a collection of cellular automata which
are all influencing each other, but basically they are data which only influence each other when they
are nearest neighbors. So the position of a thing is very important because it can only affect its
neighbors. It cannot affect directly things that are further away than a few fundamental
distances. So it's typically what you get in a pinball machine, although the pinball machine
is designed to generate random numbers. But if you could predict at infinite precision what
is happening to these balls in the machine, then they all go in a predictable orbit. They
go down the machine. And it depends on details that are too difficult for us now to calculate.
That's what the machine is made for. But in principle, everything should be predictable.
And in the cellular automaton, you build more basically on that idea. But now you say,
let's take the rules about how one object affects its neighbor. Let's suppose those
rules are completely fixed by very simple prescriptions. For instance, there's a part
here and a part here. Whenever this one starts to vibrate, the other one starts to vibrate,
and the way they react upon each other's behavior is completely fixed by some simple law.
So I could show on screen right now, just for the viewers, John Conway's Game of Life as an example.
That's a nice example except it's not reversible in time. Whereas the real world as you see it
seems to be, and I would emphasize seems to be, reversible in time. That is to say,
if you have something happening, the same event happening backwards in time, if you make a movie
of me talking, but you show a movie backwards in time, then the same equations are obeyed. Well,
actually, the situation is a little bit more difficult. You have to replace particles by
antiparticles and some mirrored particles as well. But that's a detail. The important point of the
automaton, and that is probably important if you want to impose quantum mechanics,
if you want to say that this thing actually can be turned into quantum mechanics, and probably
what you want is to have a time-reversible set of laws. The set of laws can be extremely simple,
because you only need to say what happens when a particle sees another one at its neighbor. And
if you know where all the particles are situated, you can have waves that go through this situation.
You can make it look as complicated as the real world. And that is very important. I
think the real world, to me, does not look any more complicated than this. Except that,
for the real world, I don't know the equations. I'm not going to find out anymore in my lifetime.
So we don't know the equations, but maybe one day physicists will guess the equations,
and from that guess they'll discover that not only the equations seem to agree more or less with
what they know experimentally, but it can also predict what kind of particles this will produce.
Particles are phenomena that you can also describe in these automata. Particles are quanta of energy.
That's the most precise definition. Not an infinite precise, but very precise definition
of particle. It is a quantum of energy. Energy is something you can define classically, even though
it's not quite deterministic. That's an important complication in the whole theory. But basically,
we have time, we have energy, there's momentum with other properties of the particles, and
they all interact in a completely fixed, prescribed way. If these fixed laws only
act on integers and on fixed time steps, then everything can be put in a computer, because a
computer also works with only discrete numbers and discrete time steps. But then the computer can be
extremely accurate as well. It does sometimes make a mistake because you have fluctuations,
but not very often. So most computers then agree very precisely as a result what the
outcome of an experiment will be. There's a good reason to suspect that such a theory
could also predict that actually before we understand how things happen in practice,
what we will see is that there are things that look very much like the particles that particle
physicists have been talking about for years now. So-called standard model of elementary particles.
The standard model is a quantum model, but as a quantum model, it gives you very precise
statistical predictions which can be measured and checked with experiment, and you find that
the standard model today is the best possible way we can describe these particles. So the next step
would be, if you have a discretized model like the cellular automata, that they should reproduce the
same world of standard model particles. And now the fact that you can't accept any non-integer
numbers in the cellular automaton also means that when these standard models particles interact,
they collide and they go away in different directions, then this whole phenomenon of the
collision will be described by integer numbers only. And that's very interesting from the point
of view of standard model physicists, because that's what the standard model does not have.
It also has numbers of pi floating around, or numbers which are not very precisely known,
but certainly they can fill a complete continuum of constants of nature in the standard model.
This continuum should be broken up, and that's what my theory would predict. The likely models,
the models that work in practice, will have only integers even in their coupling strength. And that
is not, as we understand the particles now, but something one might expect in the distant future
to be discovered, that yes, you can also compute how all the particles interact with integers.
So is discreteness important? Is it extremely important? So the reason is that you could
have the universe following rules that go stepwise. Well, I guess when I say stepwise,
that is discrete. But what I was going to say is there could still be some dependence
on real numbers which are continuous. So for instance, one of the updating rules could rely
on pi, all of the digits of pi. So is the discreteness through and through important?
I think yes because if you don't have discreteness but a continuum of possibilities,
the continuous numbers, the real numbers, but the real numbers, every single real number is only
specified if you have specified an infinite number of decimal places. That is very hard
to realize in a finite model like the cellular automaton. So I don't believe in the existence
of real numbers in physics. Well, that's very strange because everything in physics today
seems to be controlled by real numbers. So why am I saying that? I'm saying that this may hold
only in this idealized model or theory, which hasn't been discovered at all now,
which you don't know of any of the details, how they work. But if we find the details,
my prediction would be those details will only depend on integers, not even rationals, because
a rational number can also have infinitely many values. Only integers have finite values, and the
integers shouldn't be too big also. They should be between 1 and 2 perhaps, or between 1 and 137 or
something like that. But finite numbers, and only then can your model be deterministic without ever
needing to make statistical approximations. Whereas with real numbers, you never know for
sure whether the real numbers will hit each other or not, when two particles collide with different
impact parameters, which is controlled by a real number, if those real numbers are different,
then at one situation the particles will collide, in the other case they will not collide. But it
will be very hard to make a theory where all this will come out with certainty only. And
that's the basic demand I have for the future theory is it will only be based on certainties.
Well, we don't understand anything today, so today's science is without certainties.
Fine. So we have work to do as a scientist. We have to work to do to find this theory
which only contains certainties, and therefore it may only contain integer
numbers. Even the time steps. But time is one possible exception that things might go like
when you have embroidery. If you have a needle and a thread and the needle goes to and fro,
then the needle will follow a continuous orbit, and then depending on that continuous orbit,
the knots that you create are discrete tiles and only indicated with integer numbers. In that way,
time is formally real, but this real number won't play a role in the predictions that you
make. That's only the position of the particle as a function of time. But in the real world, time
makes so many steps that we are not even aware of the time being possibly discrete or continuous.
So there are two key people that come to mind that have worked on superdeterminism. A word
which I don't think we've said yet, but we're going to get to. And you're a large
proponent of superdeterminism. The other two are Tim Palmer and Sabine Hossenfelder.
Tim Palmer has rational quantum mechanics. So I don't know if you've looked into that,
but if you have, I would like to know what your thoughts are.
Well, I think it's a typical example of someone going very far in my direction, yes,
but not as far as I am. Because I'm saying that the numbers should never be rational,
because then you have still an infinite number of possibilities.
There should be numbers determined by reals. Of course, a rational number is a numerator
divided by a denominator. So yes, those are integers. So if the rational numbers he talks
about are really numerators and denominators, but themselves only carrying integer numbers,
even integer numbers which are restricted, then beautiful inside. But so Palmer is not precisely
as ready as I am to decide to accept only the completely integer world.
Now, with this discreteness, do you have to have a
preferred foliation in order to describe this discreteness in your model? Or is
the discreteness something else that isn't exactly space-time discreteness?
That's the hard part of the question. We have Einstein's equations. We have
curvature of space and time. So that will usually, any theory that uses that, will have
to have such sheets. And how to make those discrete is very difficult. But there is a
theory such as loop quantum gravity that tries to do something of that sort. So they have my
sympathy, but again, they're not going far enough. To my taste, we're in determinism.
Steven Wolfram is another person who doesn't go into superdeterminism but also has cellular
automata. So you're a unique blend. I want to get to how lonely it feels at another question,
but it would be great to talk about the early 2000s Steven, because now the Steven
is hypergraph Steven, but earlier it was cellular automata Steven. What is the difference between
your approach and his? Did his influence yours, or did yours influence his? Was it independent?
Maybe not quite independent. I think he was much earlier in looking at cellular automata than I am.
So if there's any... What is it? Causal priority? Priority then it belongs to him because he worked
very much earlier with cellular automata. I remember the game of life as being an example
but that has absorption and that's not really as deterministic as I wanted. But yes, I think that
Palmer's ideas and mine are very close, but they're just not quite exactly the same.
So again, when we were speaking off-air, we talked about how many people send you their theory of
everything or just their theories on physics, and most of it, it's not terribly useful to
you. There was a diamond in the rough though, from Edward Fredkin, if I'm pronouncing that correctly.
He is one of the exceptions to the rule, and the rule is basically that these people who come
with their own crazy ideas, their ideas are too crazy. And they show a lack of understanding of
what already scientists know about the world. And what scientists know is that the standard
model of the particles works extremely well. That cannot be an accident, so we want to use
that. And we don't want to throw away the standard model before we have anything better. Eventually,
the model is not infinitely good. It has some weak spots. We all know that. Scientists are
aware of this. They try to repair the weak spots, but they don't try to overthrow the standard
model entirely. Because there's so much good and sound science that went into it. So the idea is,
what is the mathematics that you need to compare the cellular automaton with the standard model or
similar models? Where is the boundary? Is there any boundary? I don't believe there is one,
but it looks like it. And of course, then you get the question that space and time
are curved according to Einstein. That again also is something we know practically with certainty
because there have been many observations that have been made that confirm Einstein's theory.
So there's not a point to start doubting on that. So those things you want to keep,
you want to keep general relativity, you want to keep the standard model. The first thing to
drop would be the non-deterministic interpretation of quantum mechanics.
But then we have to make many more steps to see how the existing understanding of
the world as you know it, how this becomes completely folded into a useful theory.
Professor, something I don't understand is if this approach,
your cellular automata approach, depends so sensitively on initial conditions such
that any stochasticity that we perceive can always be said to be just ignorance,
then given the initial conditions aren't accessible to us in anything that resembles
the precision I imagine you'd require, how could you possibly falsify your theory?
I think that's going to be very high, certainly for the time being. But as long as a theory isn't
completely understood, like we don't know exactly the automaton equations that we want to obey.
So as long as that's the case, the theory has not been even remotely, it's not totally proven to be
correct. Only if the theory would start to make predictions about standard model
interactions. For instance, the masses of the neutrinos, which you don't know very well today,
and the mass relation between other particles that we can measure but not calculate, are not in
terms of features of the theory that we completely understand. As long as that's the case, you can't,
the first declare that this model has been outlawed. We can come closer and closer to the
truth. I hope, however, that maybe with the use of artificial intelligence that is more intelligent
than the average human being, much more, then maybe machines will find a way to uncover such
a cellular automaton. Maybe the machine will know how to do quantum field theory of many,
many particles and why they can be effectively the way a cellular automaton exhibits itself.
Because I see lots of relations between a quantum theory of quantum particles on the one hand and
the cellular automaton on the other. So I see that relation. And that's where I differ from Wolfram.
So I think is the question how come that our world looks like some cellular automaton in
disguise. And he tries many examples. But I'm sure that by trying just a model of the sort you won't
get to the truth. The truth is too complicated. So I believe that we have to combine the work
from experimental scientists who measure all the properties of the standard model as accurately as
they can. And then theoreticians ask why are these different parameters that characterize the theory,
why are they related with these particular ratios? Where do these numbers come from? Then maybe one
day someone will find, oh, but this number I can recognize from the cellular automaton. It's that
number. So a famous number of that sort is the fine structure constant in electromagnetism. The
ratio between the electric charge and some other fundamental constants, if you square that, then
you get 1 over 137. But the number has many more decimal places behind the zero and the comma. And
that's a famous number that nobody can compute, but it exists, it can be measured very accurately,
but we don't know how to compute that number. And the cellular automaton, if it's worth that name,
should be able to compute where that number comes from and what it is.
Okay, this sounds like a great time to talk about
what is superdeterminism and how is it contrasted with regular determinism.
Well, it's not.
Determinism as bitten by a radioactive spider.
So what is determinism and how does that contrast with superdeterminism?
I think different people have different interpretations as to what superdeterminism
should mean. And the problem is it's something that may be beyond superdeterminism,
but you can think of that in two ways. You and I think that the laws of nature are conspiring
with each other such that we are made to believe that quantum mechanics is real,
whereas in reality it's just a statistical phenomenon. But it can also just mean that
determinism occurs at all levels in principle. So not only at the level of atoms and molecules,
but also bigger things like larger biological molecules or chemistry or even small particles
and then eventually large particles, stars, universes. They all should be
described by deterministic equations. I go to the extreme. I think in principle we have completely
deterministic equations. In practice we do not have the illusion that we will ever be able,
even the AI people will not be able to calculate how things will evolve exactly. That will be far
too complicated as ever to achieve. But we can then believe that the world has that
determinism built in those laws as well, even if we can't ever derive the laws with precision.
So if superdeterminism means that, then I'm totally behind it. That I cannot expect anything
else. That the entire world is controlled by equations that only say yes or no. And whenever
it answers a question, it never says maybe. It never gives you a probabilistic distribution.
The probability is different from zero or one. And if that superdeterminism means that,
I'm totally in favor of it. But sometimes people believe that superdeterminism means that, okay,
the world is deterministic, but there's a God pulling on some switches to make things
happen the way you are caught into thinking that quantum mechanics is the truth theory
or something of that sort. Some mysterious intervention of a divine ghost of something
that makes things happen that otherwise would not be understandable. If that is
what superdeterminism means, then that's not what I believe at all. So there's nothing,
nothing will be needed to other than complete deterministic laws.
So you're much more in line with Einstein who believed God doesn't play dice.
I think Einstein would agree with me here. Or I would agree with Einstein. He was the first.
Okay, so superdeterminism is nothing over and above determinism. It's actually just determinism
through and through. So most people, they think, well, Newton's laws are deterministic. There's
some wiggle room there with Norton's dome. Super-determinism is determinism all the way.
Yes. No matter how complicated this thing is that you're looking at,
in principle its laws are deterministic.
The subtlety here is that there's Bell's theorem, which seems to exclude determinism,
and one of the loopholes or one of the assumptions is statistical independence. So superdeterminism
is usually spoken about as taking statistical dependence. So can you please explain what
statistical independence is, why it's relevant to Bell's theorem and then where you land on it?
Well, I think Bell, with all respect, he was a very nice person and modest and he had just his
ideas and he tried to prove, to understand how determinism works. And then he found that in his
theories the opposite is true so that determinism didn't work for his theories. But I think he made
a very elementary error, I would say mistake. And that is to say that things that happened in
the past have nothing to do with what happened at the present. So Bob and Alice, his two observers
in his experiment, the Gedankenexperiment, but still it's an experiment. Bob and Alice,
they decide the last split second what to measure, whether it's a spin up or inside this action
or down or whatever. Or you could talk about photons, you could talk about spinors, anyway.
But Bell assumed that the decisions made by Bob and Alice to measure something is independent of
what happens in the past. And my reaction was, well, I first didn't really see clearly what he
was trying to say. But then I realized that what he was trying to say is something that cannot be
true. That Bob and Alice cannot change their mind without something happening in the past
that caused them to change their minds. And if you do think so, then you have assumed that Bob
and Alice do something without any explanation in the past. But that's precisely what my idea is.
So the first thing about superdeterminism or superdeterminism, whatever, says that no,
everything we do is also controlled by the same theory. So our decision to measure this,
to measure that, to measure that, also depends on what happened in the past. And if Bell says
the opposite, and he needed the opposite of that, he needed that the decision of Bob
and Alice to measure something is independent of what the atoms did in the distant past.
Just because he needed that, I say, well, that disproves his approach as being anything else,
anything that would disprove the indeterminism or disprove the determinism of quantum mechanics. No,
he made an assumption which you cannot hold. If you believe in superdeterminism,
you have to believe in superdeterminism all the way. And that's what he didn't do.
Now what about the critique that super-determinism makes experimental science meaningless?
It makes experimental science harder, but not meaningless.
Why not?
I mean, we're doing science all the way and the interpretation of the quantum equations
that we get is just something else. It means that the ultimate source of the
quantum equations is not what people think they are. It's not that there are many realities.
And I think actually Bell also showed that because he made this assumption that these
particles in the distant past can have any probabilistic distribution regardless as to
what the decisions are that Bob and Alice make. No. As soon as Bob and Alice make a decision,
you can point out in a deterministic, so in a really deterministic theory you can point
exactly which atom in the past has made Bob and Alice to change the settings of their measurement.
So, okay, allow me to be precise. I'll give some example. Let's suppose you have a thousand mice.
Some of these mice are going to be predisposed to cancer and some are not. And we just don't
know which one of these mice are predisposed. So we just are going to randomly divide them.
And how do we randomly divide them? Well, we pick the two millionth digit of pi and we say if that
digit is odd, then this mouse here, this mouse right up front will go to the left in one group.
And then if the digit is even, then the mouse will go to the right and we just keep sorting based on,
okay, now the three millionth digit of pi, now the four millionth and so on. So standard statistics
would say that each group would have roughly the same percentage of cancer-prone mice. If we later
see more cancer in one group that smokes, say we make these mice smoke, so we give
them cigarettes or what have you, then we conclude that smoking causes cancer. If we deny statistical
independence it means that somehow these mice could have conspired, not the mice themselves,
but somehow the universe conspired such that the smoking group just happened to get more
cancer-prone mice in it. And I remember that tobacco companies used this to say that this is
one of the reasons why smoking doesn't necessarily cause cancer. So how does statistical independence
not fall prey to these sorts of arguments? Because Alice and Bob could choose their
measurement settings based on coins or quantum random generators or or quasar photons. There
would still somehow be correlations there. Explain this for me. Help me understand.
Well, I think what one may well expect from a deterministic theory is that the
ratios of events are more or less the way you expect them. So when you try to understand how
the deterministic theory works, you will find it's far too complicated to calculate exactly
what happens. So we can talk about exactly what will happen when exactly you do your experiment.
The millionth mouse goes in that direction and one millionth mouse goes in that direction. If that's
what you do, then we know very well that we'll never be able to compute with infinite precision
in such a deterministic world what will happen. So at some point one has to make an assumption.
And the assumptions must sound reasonable. The assumption will be that all these mice are
controlled by the same biological rules as others. Some mice will be more immune against a disease
that gives them cancer. Others will be more sensitive to cancer cells. But you can compute all
these things from the model more easily than to compute literally what every single mouse will do,
what will happen to it. And the same holds for insurance companies. Insurance companies never
worry about whether the atoms that were taking place, whether the car accident would take place,
that those atoms were in the wrong position. You won't blame the atoms. They say, well,
they can be in any position, but there are so many of such initial states we can use the states that
we can use to see that randomness does enter into our world whether we like it or not. So even in a
deterministic theory you will have randomness in practice. And so then that wipes away the
mouse problem. Because then you say, well, every mouse is controlled by random phenomena anyway.
My deterministic theory of the deterministic world will give a prediction, if it could, if it
could be handled in the position. But we can't and we never will be. So we are so far away from that
situation that we can make such measurements. The next best thing is to use the biological
arguments to see that someone in the insurance company is cheating and so on and so forth. We
can name all sorts of reasons for one mouse to die sooner than another mouse. Or a cat, we can't even
name any other mouse to die sooner than another mouse being survived or death. That in practice
you never need to worry that this is going to be contradicting the deterministic theory.
Okay, so this is a great point for people who just happened to skip forward to this point in
the conversation. Most of the groundwork has been laid. Why don't you just outline what is
your view of quantum mechanics? What is going on? What is the cellular automata approach? Now
I know you've already talked about it, but I'm just saying let's recapitulate
it. So what does standard quantum theory say? And then what does your approach say?
What my ideas about quantum mechanics say is that there is a way to identify parameters. You call
them hidden variables. You can call them any way you like. Let's call them hidden variables
because that has been most hopefully debated in the past. There are variables, let's call them
hidden variables, which can only take the value yes or no, but nothing in between. Everything
is determined by certain certainty laws. In principle, it would be possible to compute what
such a model does in this infinite precision. In practice, of course, it's nearly never possible.
Even if you have an experiment at CERN when two beams of particles hit each other, no matter how
sharp you focus one beam on the other, the other beam. You still get some possibility of arbitrary
fluctuations that you don't have under control sufficient to make that what happens after the
collision is all possibilities. The particle can go in all directions with different probabilities.
By the way, there might be correlations such that they give you a small peak in your
observations. Such a peak might be the effect of a new particle. These things also happen.
But the theory will not work better than ordinary quantum mechanics in the best of
all possible worlds. So the theory cannot be used to make better quantum mechanical
calculations. But it can be used to understand what the phenomena are and why the phenomena
are there. Why are there mice that die more easily from smoking cigarettes and others not? And so on.
So those questions you have to answer not by being a scientist but by being a biologist or a doctor
who is investigating with all precision as he can to see what are the outcomes of this experiment,
what are the spreadings, what can happen, what can you do. That is not going to be any better
with the deterministic theory. But what will be done better is that you can understand where
all these laws come from. In particular, the standard model of elementary particles
is the first in line to be researched using statistical, using deterministic phenomena.
So, Professor, since you have such interesting views on or differing views on quantum mechanics,
do you have any differing views on quantum gravity? So for instance whatever the mainline
approaches are, do you disagree with them at some fundamental level? Is there something
that restricts what the mainline approaches would be if cellular automata were true?
No, I think it's basically incorrect to give a different role to gravity than to all the other
interactions. So normally we have electromagnetism that determines how particles collide. Sometimes
there are strong and weak forces. But gravity is one of these other forces. It happens to be
a lot weaker than the others. But in principle gravity should be controlled by exactly the same
situation. There are particles called gravitons. There are black holes. There are all these other
things which can happen in the gravitational theory. They are all controlled by deterministic
laws, which will be very difficult in the case of gravity. It really is very difficult even
to think of how deterministic laws could be working in this case. So yes, this is a
difficult problem. But I don't see why it should be impossible. There's no no-go theorem that, no,
you can't do that. People write no-go theorems just like Bell did with Bell inequalities,
which I think, I think it's a no-go theorem that you can punch through. I think you can
also punch through the no-go theorems for gravity. It's just hard. And I think you
have to be very intelligent, very smart, and very resourceful, and perhaps help with very
clever experiments to see how this works, how you can bridge the gap between the elementary
particles on one hand and the gravitational particles on the other. There's no doubt in
mind that you have to use the same technique of quantum mechanics in both cases. So yes,
that means quantum gravity as such works. In fact, classical gravity only works in the cases where
the quantum effects are insignificant. You can't see them, but they are there and they are there
because there are still statistical phenomena that have taken place every now and then.
Ah, okay. So I interviewed Claudia de Rham of Massive Gravity,
the interview I'll place on screen. And she had this advice to her students,
which is that, sure, there may be no-go theorems. You should take them seriously,
but don't take them as a total no, because there are ways to evade them. And her massive graviton
had a specific potential that removes or decouples the ghosts at all orders. Also,
there's a Weinberg-Witten theorem, which she evades because she has a massive graviton. Do
you give similar advice to your students that if you're violating some... sacred assumption. Well,
yes, you should be concerned about it, but don't be too concerned. You can find your way around it.
I would certainly say don't be too concerned about it. Quite the opposite. If your theory
disagrees strongly with the existing opinion about the situation, maybe it's a good idea to
study it because then not so many people have studied the opposite possibility yet. But in
reality you have to realize that most likely the correct answers, as history has shown,
most likely the correct answers are by combining different phenomena. Like in the case of Maxwell
it was combining electricity and magnetism as one theory. So that was a famous example.
But there are other examples where you can see where gravity and elementary particles meet each
other. For instance, the gravitons. They will be difficult or impossible to observe. But in theory,
they are there and they are just like photons. In many respects, they look very much like
photons. And you can possibly learn new things, particularly if you take one step backwards. And
I also have a strong advice for students. If you don't understand something and you don't believe
that what you read in the books makes sense, just make a step backwards. Try to ask the question,
why do people say these things in the first place? Can it be that they didn't listen to each
other? If they listened to each other, they would realize that they both made some mistakes or some
make bigger mistakes than others. We all make mistakes. So take that... so let's put it into
account and don't let you have yourself scared away from viewpoints which might be more useful
by getting in a combination of different theories together in one theory. That is often a sign that
you might be on a new track, which is important. But many students like to do like their masters,
like disbelieve everything, quantum gravity doesn't exist or something like that. I don't
know what such a theory looks like, but it doesn't look like the theory I would like to defend.
Do you find that many of the master's students are the ones with ideas that
are trying to discard most of standard physics and reformulate everything? Or
do you find that's mostly what characterizes your inbox compared to your master's students?
No, I think that is what happens when you begin as a physics student. And that are the good
students. They doubt on anything they learn. They say it could be different. Let's assume
that what this teacher says is not true. Why did he say this? And then some do long calculations,
some do short calculations, but usually when they did the calculations, say, yes,
actually this teacher wasn't so bad after all. He is right. And what I first thought didn't
hold. So you have to understand that the way you have to understand nature. So try to take things
that seem to be not related yet giving different answers to different scenarios. Let's try to see
if we can find a common denominator, a theory that works for both of them.
So that would be one certain... any certain alleys of that sort that you can still investigate.
If I understood correctly from our conversation off-air, you suggested
that some composite particles, sorry, that some of what we think of as elementary particles may
be confined composite particles, but I'm not sure if I misunderstood that.
Well, the question is again in the other direction. What makes a particle
elementary? And I was once also entering a discussion that people try to define
elementary particles as opposed to composite particles. Then my immediate answer was,
well, a composite particle is composite if it makes sense, if it's useful to consider it as
such. It's elementary if you can't identify any composite ingredients of the particle anymore,
then it's an elementary particle. Such as the photon is basically elementary. The graviton
will be basically in elementary particles. But you cannot try to make such definitions with infinite
precision. If you use infinite precision, you know that a photon every now and then will look like an
electron to an electron and then come back again. So the things that first look easy at one step,
they become more complicated after more steps. But still, physics is a science where there's no such
certainty today. There's no such certainty as I would like to see. But I want to work my way to
theories which have more certainty built in than normally. And that I think is an interesting alley
to investigate today. Can you make theories which are more certain than others?
And I found a very simple theory of that sort. I call it the grandfather's clock, a pendulum clock.
So a pendulum has a pendulum which it goes one per second, it makes a full twist here. And then
it has some gears in them. And while the gears are rotating, the pendulum does this. And I'm saying
yes, this is a model that has periodic behavior and it has linear behavior in how the hands of the
flocks move continuously. And, both obey the same quantum laws. So you have a single set of quantum
equations for the entire pendulum clock. And the nice thing about the pendulum clock is that
on the one hand it has an oscillator, but it's a quantum oscillator. The quantum oscillators are
known by having discretized energy levels and it's typically a quantum situation. But nevertheless,
the entire model has also classical behavior. The hands of the clock move classically. So you have
a collision between deterministic theories and quantum theories in one object,
the pendulum clock. Which is why I like the name pendulum clock, although you don't have to put
all the ornamentations on it. It's still a thing that combines quantum mechanics
with deterministic behavior. My belief is that you can do that with quantum mechanics itself.
And there are many pendulum clocks, more... so this would be the beginning of a research into
completely deterministic theories which look quantum mechanical at first sight.
So, Professor, speaking of quantum mechanical, I want to use that word quantum because we talked
about quantum clones before. It's more recent work of yours. So there's work by Neil Turok
and Latham Boyle about black hole horizons acting as mirrors. And you also have a theory of mirrors
at the horizon. So please talk about that and how yours is distinguished from their model.
Yeah, I don't know if this works. Let me see. Perfect. Great. This describes a black hole. And
the feature is that a black hole is a region of space-time which is accelerated. And when
it is accelerated, it has horizons. The dark blue lines are horizons. The other arrows are
particles going into the black hole and this is a particle coming out of a black hole. And this
is the way I think one should understand how black holes behave in practice. But,
now maybe you can repeat here. So there's a mapping between the future... so no it is not
right. The whole thing is yes, you want to get not to disobey unitarity or determinism.
So now when people draw a black hole they say yes but there's a similar space at the other
side. Let me quickly draw it. There's another universe at the other side here. Great. And
so when you have data in this whole system, you have data here and you have data there. However,
this data there cannot be realistic. Because if that were a genuine... and according to the
equations, this space here looks exactly identical to that one. So this looks like a clone of that.
But normally when you do physics, it isn't a clone because you can throw in a particle here
without throwing in a particle here. But you can also say, well, maybe if you throw in a particle
here, then automatically an anti-observer, anti-physicist will also throw a particle in here.
So then I say this is exactly a clone of that. That means you can throw in a particle here. You
can leave away this green region altogether. So I talk about a single black hole now. And maybe
that is enough to describe all the data that are there. The advantage of that is that when you do
this calculation, now when determinism takes place in this one universe, then determinism takes place
in the other one as well. In fact, this whole model, if this is just a clone of that, the
whole thing can be called deterministic. If this is a separate... the universe is going to be very
high because these particles will disappear into the infinite future. And these particles will come
from the past, long ago. But it's very difficult to say that this particle that gets out depends
on the particle that moves in. And that's what you want in a good theory. So determinism is helped by
identifying these two regions. And the side effect of that is that by identifying the two regions,
you make that the end of the universe is going to be very high. So the entropy and other properties
of the particles here is only half of what you thought it was. So when you have two units,
the entropy is much larger. Now temperature is a function of entropy in this model. So if you
multiply the number of universes, or you decrease the number of universes by a factor of two,
you increase the temperature in both of them by a factor of two. So this theory also predicts a
factor of two difference from the usual outcome that people got out of this calculation.
So the Hawking temperature in your model would be times two of what the
ordinary calculation is. This makes it even distinguishable experimentally potentially if
we can get close enough to a black hole and measure its temperature and so on.
It will be very high because in practice such black holes will be very far away if they exist
at all in our universe because we cannot really... we don't understand the universe
at the moment that it could have created such microscopic black holes. Because they're not...
it's not possible to make those black holes out of ordinary matter. The temperature is too high.
So what you're saying is that when a particle is incoming into a black hole,
it's not that that particle then appears somehow in the
past because that would create a time like, a closed time like...
It's more subtle than that. Both the in and the out-going particle will go through a quantum
regime. And right when they both go through this point, then the laws which are obviously
correct here and obviously correct here are not obviously correct at this point. There's
something else happening there. And that saves us. That makes the theory useful again. Because
all these particles will, if you just let time do its work, these out-going particles come out
much less. So, you can see that data, they'll come from this point. And the ingoing particles
will go in not here, but also here. Then you find that you have to reconsider those laws of
physics. And that takes away the contradictions that you normally would get. Whereas in this
world of two universes, you get contradictions that are much more difficult to avoid.
So, paint the picture for the audience member who's wondering, okay, if I, the person who's
listening, approach a black hole and assuming we get rid of spaghettification and so on,
what occurs to them? What do they see? Do they see themselves as an antimatter twin that they
just touch and annihilate into a sea of photons? Like, what do they see when someone falls in?
In this model, that would be different than the ordinary model. The thing is that the physics
happening here on this one and on that universe is not really physical at all. Because the physics is
just basically this half. Where you have ingoing particles going in here and outgoing particles
going out here. What they do in between has anything to do with it. It's a boundary condition
of this horizon. This horizon is such that if you enter it here, you get out there. But there's
something very important in that change. It's the the position of this particle which turns into
momentum of that particle. There's a very strange kind of mix between position and momentum. But
just in accordance with quantum mechanics. Quantum mechanics says that what you must have. And then
the theory works extremely well I believe. But you cannot even ask the question what happens when
you go through it? No. When you go through this horizon in practice you will break into pieces
and you come out shattered all over this past horizon. You will come out as another particle.
And so then there's no information paradox.
There's no information paradox. Except perhaps the black hole is not exactly what you think
it is. And that's usually the answer in physics, in many branches of physics.
You're only getting a successful theory if you first declare that something you thought
to be accurate actually wasn't very precise. So what I'm saying here about the black holes is an
approximate description of black holes, but not infinitely precise when you go to very tiny ones.
Now, this doesn't completely eliminate singularities. You get conical singularities, no?
Yes.
So why is that an improvement?
It isn't. At first sight, it means that there's something very basically going wrong
at this point. Because when you fold, when you say this is a clone of that, then it
means that you actually have to fold out a piece of paper double. And that folding, that this...
Can you lift up the paper? If you don't mind,
just lift it up just so that the audience can see it some more? More? Yeah, perfect.
Okay. If you, yeah. So now I again forgot what I wanted to say.
Oh, no, that's fine. You were talking about
the singularity. And you were talking about how you have to fold the paper.
Yes. If you fold the paper, you get like when you have a bag of French fries,
then at this point where they are all collected, there's a singularity. It's
a very mild singularity. You can undo it by making space-time a little more inaccurate here,
and then the singularity disappears. But in the limit that you have the art description now,
this looks like a singularity. That's called the conical singularity. That singularity,
however, is the one that already occurs in ordinary string theory.
String theories have all the singularities, very mild singularities at such a point where
two strings interact. And yeah, or actually it's the string itself, the position of the
string itself also is a singularity. But those are usually much milder because the string
coupling constant is much smaller. So this is like a string, but it's a very strong string.
Right, right. It's a Euclidean string or is it?
It's a Euclidean string. Yes.
Okay.
That's the thing that string theorists talk about,
but it's very similar to the thing string theorists talk about.
Now this factor of two, by the way, does that factor survive if the
back reaction is non-perturbative? Like fully non-perturbative? Or is it independent of that?
It's independent of that. I think the description I have here is very much like a zeroth-order
description if you throw away the higher-order correction terms. There will be correction terms,
but very small. So they don't take away the basic properties of the theory.
I see. Thank you so much, Professor. I know that you have to get going. Why
don't we talk about what you're working on these days? What's
new? What's going on in your life? Where are you headed, research-wise?
It is a black hole problem because the model I have right now is not accurate enough. It's
accurate, I believe, but some of the details are not very well understood. In particular,
this conical singularity at the origin, I want to understand it better. And I want
to also understand how to confront it with the particles of the standard model to see
how they interact with the black hole. I want that to be very precisely described
or some perturbative theory. But when you write down perturbation expansion,
you have to say perturbation in what? What is the small parameter? And usually that is the
small parameter is that the masses of the standard model particles are much, much lighter than the
masses of the black holes that you're looking at. And that means that in all our situations
you will be very precise in saying that the first order calculation is probably far more dominant
than any of the others. But I want to have this ready in the form of a textbook, where I say this
textbook has the same kind of introduction as any textbook in quantum field theory. In the old days,
quantum field theory was a very difficult subject. It needed to be explained in detail how it works.
This is also a difficult subject, as we explained in detail how it works,
but there will be no doubt that the description is correct. You can always doubt whether the
entire theory is correct, and that's allowed. You can always ask nasty questions, and they will be
asked nasty questions. But in principle, I want to get it as clear as I can get the whole theory.
Did you have a talk in Marseille about asymptotic freedom?
Yes, that's an interesting thing that happened. We were in Marseille and I already knew Professor
Kurt Symanzik. He's a very nice person, a very good thinker. He was doing very smart
mathematics which was very difficult for people to understand. But he happened to meet each other
at that conference. It was a few years after... here I learned lots of things from him at his
Cargèse School. But I was again in Marseille and there he was. And when we came out of the plane we
realized we had both been using the same airplane at the airport of Marseille. And there we asked
each other what we were doing and he said, “I'm working on theories that have the wrong sign of
the coupling constants.” And naturally my question was, why do you choose the wrong sign? He said,
“Well then, they have an important property that we call asymptotic freedom or something like
that.” I don't think he called it that, but there was an important property which nowadays would be
called asymptotic freedom. He said, do you know that you can use the gauge theory to get the same
effect and you don't have to choose the wrong sign or couplings? You just choose the couplings as
they really are thought to be. But this theory has this property already. And he said, “No, I
didn't know that. How do you know?” I said, well, I computed it. He said, “Well, if that's true,
you should publish it very quickly, because if you don't, someone else will make that discovery.
And this is important. It explains strong interactions.” And although I agreed with him,
I had so many other things to do that I postponed writing down, because I had used different ways
than other people who do these calculations. So I would have to explain everything before
I could give the answer. What I should have done, I should have written just a physics letter paper,
a very short paper, saying this is my result and this property is called asymptotic freedom. But
now what happened was I waited much too long and there came Gross, Wilczek, and Pollitzer,
who independently had arrived at the same result, that these theories are asymptotically free. So,
well, then Symanzik was the first to say, if you announce something in a conference,
that counts as far as priority goes. But, well, I hadn't written it down properly
and he thought he should talk about it because maybe I probably made a sign error somewhere.
So I couldn't believe that gauge theories are so much different from scalar theories that
you could change the sign of the beta function, which was the essential thing that happened here.
Now before you go, Professor, you have a program on how to become a good theoretical physicist.
I'll place that URL on screen, a link to that website as well. Can you please talk about it
for those who are listening who want to become researchers in physics, new students, maybe some
existing researchers who want to improve their skills, follow the advice of a Nobel laureate?
Yes. Indeed I get many letters by people who have a view of nature that isn't quite real,
that doesn't agree with many of the things we know very well in science.
So I thought, let me try to give an answer to all of them, all of the more serious researchers,
that they have to know about physics. And of course, all the standard things in physics,
which you shouldn't skip. You shouldn't skip the understanding of Newton's laws or why planets move
in elliptical orbits. You shouldn't skip the relations of the electric and magnetic fields
by Maxwell. All those topics you have to learn first. You have to learn what thermodynamics
is. And I mentioned sort of a dozen topics in theoretical physics that you really have to
understand. When you understand all these theories and you understand also what the limits are,
like quantum mechanics, it's not believed to be exactly true, but true enough for practical
purposes. And you have to understand that. Then you can try to see, if you see any gap here,
that you can fill in with a personal calculation that should improve what we know now. And that's
the difficult part of this. You shouldn't just discard the old theories without first having an
idea about what to replace it with and what would be better than the replaced theories.
And now I get letters, of course, of people who discard the old theory and replace it with
something they think is better. But immediately, yes, with those equations that you can use,
you can't use that to calculate the magnetic moment of the electron, or you can't use that to
calculate the thermal properties of particles near the black hole. And all these kind of questions,
if you now do know how to calculate. So you first have to know the existing and verified part of
physics, which is an enormous amount of work. More than 100, maybe 200 years of science. It now fits
in one big textbook. But to read it all, it takes lots and lots of time and effort,
and you have to calculate, not just read it, but also do the calculations to see that it works.
So it can't just be that one's new theory has to recapitulate all of the 200 years of science,
of physics in particular, because even you're a champion of cellular automata,
and someone could say, well, where's the magnetic moment of the electron?
To even five decimal places, you would say, well, that's not what this theory is about,
I haven't gotten to that level. So it has to be more than just reproduced 200 years.
Yes it is of course the reason why I didn't write so many papers on cellular automata because there
are so many things I don't know. But where I disagree with Steve Wolfram who wrote a very
thick book about cellular automata but the book contains not much information that I can use. I
want the rule, if you have a cellular automaton of this and that sort, now find which elementary
particles will occur in nature because of the cellular automaton behavior. I think
that is possible in principle. Those particles might look like standard model particles, but
what the exact rules are and how to do this calculation is still way beyond me, because
it's very, very difficult to see how these things hang together. Eventually, as people also said 100
years ago about relativity theory and quantum mechanics and particles, they also thought it
was infinitely complicated. But now we have found the answers. So one day the answers will be found.
And when the answers are found it will be in large part thanks to you. Thank you very much.
Thank you. Thank you very much. Bye-bye.
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