Eric Weinstein: Hello, this is Eric with two pieces of housekeeping before we get
to today's episode with surger Penrose.
Now, in the first place, we released episode 19 on the biomedical implications
of breaths, evolutionary prediction from first principles of elongated telomeres
and laboratory rodents.
I think it's a significant enough episode and we've had so much feedback.
Around it.
Before we continue any kind of line of thinking surrounding that episode, we'll
wait for my brother and his wife, Heather highing, to return from the Amazon where
they're currently incommunicado.
So thanks for all the feedback.
It's been very interesting to process.
The second piece of housekeeping surrounds today's episode with Roger Penrose.
Now I know what I'm supposed to do.
I'm supposed to talk about quantum consciousness and the emperor's new mind.
Maybe ask Roger about the many worlds interpretation of quantum mechanics or the
weirdness of quantum entanglement.
I'm actually not that interested.
I also don't want to go back to his earliest work on singularities and general
relativity with Stephen Hawking.
What I instead want to do is to remind you what Roger is in fact famous for.
He's one of the greatest geometric physicists now living.
He's perhaps the best a descendant of Albert Einstein currently.
Still working in theoretical physics in this particular line of thought.
I also think he's a great example of what the UK does well.
He has a very idiosyncratic approach to trying to solve the deepest problems in
theoretical physics called twister theory.
I'm not expert in it, and I can't always follow it.
So if you're not following everything, today's episode, instead of deciding that
the episode has somehow failed, you try to remember that.
People who are working in mathematics and theoretical physics spend most of their
time listening to colleagues, completely lost as to what their colleagues are
saying.
So if you start to feel that you are being left behind by some line of thinking, what
we do is in general wait to see if another line of thinking opens up that we can try
to catch.
You're not going to get all of the waves.
And in fact, the same thing is happening to me while I'm interviewing Roger.
He's not understanding everything I'm saying.
I'm not understanding everything he's saying.
And in fact, this is normal.
So what I would like to do is to instead present you guys with an idea of what
science actually sounds like when people are talking from two slightly different
perspectives, we spend an awful lot of time simply trying to understand each
other.
And if that feels a little bit uncomfortable, well then in fact, you're
getting a true scientific experience, which is often very different than what
you're getting when everything is pre chewed and spoonfed.
Hope you enjoy it.
Without further ado, sir Roger Penrose.
Hello, you found the portal.
I'm your host Eric Weinstein, and I'm here today with none other than sir Roger
Penrose.
Roger, welcome.
Sir Roger Penrose: Hello.
Good to be here.
Eric Weinstein: Good to have you.
Um, I'm extremely excited about having you here.
Uh, there are lots of questions that you typically get asked these days.
Many of them about consciousness, some of them about, um, art objects that come out
of your thinking.
But I know you in a professional capacity has one of the important, most important
people at the nexus of geometry and physics.
In our time.
Of course, you can't say that you can make all sorts of faces, but I can assure you
that it's true.
You know, there's a Leonard Cohen quote where, uh, from a song called the future
where he says, uh, you don't know me from the wind.
You never will.
You never did.
But I'm the little Jew that wrote the Bible, and I have.
What I considered to be the Bible right here, which is a book you wrote called the
road to reality, which there's no getting away from maybe, in my opinion, the most
important modern book of our time.
Because what it tries to do is to summarize what we know about the nature of
all of this.
At the.
Deepest level.
And I think what I want to do is to introduce you to our audience, which has
been habituated, uh, over perhaps 16 or so, uh, interviews not to expect to
understand everything.
Um, they want to work.
They want to hear conversations unlike any they've heard.
And so we'll do some combination of explaining things, but some combination of
allowing them to look up things, uh, in their own free time.
If you're game, shall we talk about the road to reality?
You
Sir Roger Penrose: can talk about that.
Eric Weinstein: It'd be great.
So where.
Where are we in the history of coming to understand what this place is in which we
find ourselves, what we are made out of, and what we know about our own context.
Sir Roger Penrose: It's a very tough question then.
I mean, when I wrote that book, it was no more or less the state of the world at the
time.
I now feel I should rewrite part of it because things have changed, uh, in one
important way in particular as far as I'm concerned with other people agree with me
as another question.
But, uh, I don't think I'm going to rewrite it because it was such an effort
and I don't think I would be liking to live long enough to do a good job out of
it.
Eric Weinstein: Has that much really changed since you wrote the book?
Sir Roger Penrose: And a lot of level, a lot has not changed.
The thing that has changed in my view, he sees.
Whether people agree with me on this is another question is to do with cosmology,
right?
You see, I have a proposal, which I didn't have.
I mean, it's new since the book is not all that new, because it's about 15 years old,
but it's new.
Since I wrote that book.
Eric Weinstein: And in our timescales.
That's quite new now.
Sir Roger Penrose: That's pretty new.
Eric Weinstein: Let's just, just to get some context.
You were born in the early 1930s.
Yes.
Okay.
You, um, you got a chance to live through.
Uh, if not the original general relativistic and quantum revolutions,
there are consequences.
Um, in particular, you were able to take classes from people like Paul Dirac who
scarcely seems like a, a human being sometimes more like a God.
Uh.
Sir Roger Penrose: Oh yeah.
That was an experience.
Yes.
Uh, with the, I, when I was at Cambridge as a graduate student, you saw, I did my
undergraduate work at London university, university college, and then I went to
Cambridge as a graduate student, and I went to do algebra, geometry.
So I wasn't trying to do physics at all.
Uh.
And I, I encountered a friend of my brother's Dennis Shama when I think I was
at university college as an undergraduate, and he gave a series of talks on a
cosmology, but started with the, the earth.
And then he sort of worked his way out and then talked about what was then.
Referred to as the steady state theory, uh, where the galaxies, the universe
expands and expands and expands.
But it doesn't, it doesn't change because all the time there was new matcha created
hydrogen and the universe expands, and then you've got new material and it.
Keeps replenishing, uh, what's gets lost.
And I thought it was quite an intriguing, I mean, Dennis was a great fan of this
model, and so I was taken by us, so that, well, the story was that I was in
Cambridge visiting my brother, my older brother Oliver.
Who did statistical mechanics, and he was actually much more precocious than I was.
He was two years ahead, and he was, I think, finishing his research there.
But, um, I had been listening to these talks by Fred Hoyle, and he was talking, I
think in his last talk about how in the steady state model, the galaxies expands
away, expanded away, and then when they reached the speed of light, they
disappear.
And I thought, that can't be quite right.
And I started drawing pictures with light cones and things like this, and I thought,
well, they would sit, they would fade, gradually fade, but they wouldn't just
disappear.
And when I visited Cambridge, eventually my brother and we were at this.
The Kingswood restaurant in Cambridge, and I said to my brother, I said, well, look,
I don't understand what Fred was saying.
It doesn't sort of make sense to me.
And he said, well, I don't know about cosmology, but sitting over there on the
table is a friend of mine.
He knows all the answers to these things.
And that was Dennis Shama.
And so I explained this problem I had to Dennis, and he was pretty impressed
because he didn't, he said he didn't know the answer, but he would ask Fred, Fred
Hoyle, and the main thing was that when I did come up to do graduate work in gen,
in.
Uh, algebra, geometry, uh, Dennis decided to take me under his wing and try to
persuade me to change my subject and do cosmology
Eric Weinstein: simultaneously under the great geometer Hodge as well as Dennis
Shama.
Sir Roger Penrose: Well Hodge was my supervisor.
Alright.
See, Dennis was just a friend.
I see how your son, I supervise originally until he threw me out and taught, became
my supervisor.
That's another little story.
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Sir Roger Penrose: Dennis just wanted to get me.
Interested do working cosmology.
This was it.
I never, he wanted me to change my subject.
I learned an awful lot from Dennis about physics because Dennis sort of knew
everything and everybody, and he had a real knack of getting, if he thought two
people should meet each other, he got made sure they did meet each other.
In one case it was Stephen Hawking, but, uh.
Dennis was actually I, when you mentioned Dirac Dennis was actually the last
graduate.
Well, at the time he was the only graduate student of directs.
Is that right?
Yes.
Then this was was direct.
Direct
Eric Weinstein: was famously sort of a difficult, I think that, you know, in
recent years, this book came out of Graham from Ella, the strangest man that puts,
directs bizarreness, uh,
Sir Roger Penrose: was difficult to get to know.
But there's a bit of an irony here.
I mean, certainly he was hard for physicists and so on to get to know him.
Now there were two people.
Eric Weinstein: And actually maybe if I could just say one thing to our listeners.
Yes.
In my estimation, if not yours, Dereck would be neck and neck with Einstein for
the greatest of 20th century physicists.
Sir Roger Penrose: I think I wouldn't be far off that, that description.
Eric Weinstein: For some reason, his press wasn't nearly as good.
Maybe because of his hair.
I don't
Sir Roger Penrose: know.
Well, he didn't talk much.
This is one of the problems.
No, I agree.
I think he was, um, I mean, you think about, Oh, me, quantum mechanics, people
who develop that amazing subject and direct was really the one who put it all
in order.
And so
Eric Weinstein: on.
Is, is, uh, and this gets to a very odd issue, which is that you have wielded
taste and beauty as a weapon your entire life.
Your drawings are among the most compelling.
I remember the first time.
Well, one of the things I've done using our friend Joe Rogan's program is to push
out discussion of the hop fibrations because it's the only nontrivial principle
bundle that can be visually seen.
And since the world seems to be about principle bundles, it's a bit odd that the
general population doesn't know that stuff of which we are
Sir Roger Penrose: the hop fibrations or the Clifford parallels.
Was instrumental in the subject of Trista theory.
Eric Weinstein: Well, but the first time I ever saw a diagram, it was somebody
reproducing a diagram they had seen of yours.
And so the way in which you have used art and sketches,
Sir Roger Penrose: it was drawn by hand largely.
I mean, there were, I think, some circles involved, which I use a compass for, but
basically I draped my hand.
There were two versions of it.
The first one was more.
I sort of threaded, I first one was, had more circles in it, and I thought I'd draw
a little more simply in the second version, but actually I had three
versions.
The third version is in the, uh, road to reality.
But, um, I'm not sure it's the best.
I think the second version perhaps is the best.
Eric Weinstein: So, so Daruk.
Getting back to it had this elegance of mind that was unrelenting.
Yes.
And he famously brought in these bizarre objects with which some of us are
obsessed.
Others of us don't understand the obsession called spinners, which sort of
are a prerequisite to getting to twister theory, which you've popularized.
Sir Roger Penrose: Well sort of.
And I went to the UC direct, gave a course of lectures in quantum mechanics, and the
first course was sort of basic quantum mechanics.
And the second course was on quantum field theory, but also spinners.
And there's an interesting story about that, which I don't know the answer to in
the second course.
He deviated from his normal course of lectures.
Now, I understood when I talked to Graham , who wrote this biography of Dereck, um,
I understand from grand formula that when I described it.
Direct deviated from his normal course to give two or three lectures on two
components, spinous, which for me were absolutely what I needed.
You see, I learned from my work on algebra two geometry, geometry, which ended up by
trying to understand.
Tenseness systems as abs abstract systems and things which you can't represent in
terms of
Eric Weinstein: compounding.
I should just say that in terms of these two components, spin as you're talking,
you know, for the lay audience, all of the matter that they think about whether it's
in bound up in electrons or the corks that make up protons and neutrons.
If you think of these things as waves, which many people in our audience will be
familiar with that concept.
The question is, what are they weight?
What medium are they waves in?
And they're.
The medium would be a medium of spinners, which is not something that's easy for
people to understand.
Sir Roger Penrose: Yeah.
When it's, they're not.
And certainly the formulism you see, Dennis, I told him I need to understand
about spinners, and particularly the simplest ones are these two components,
spinners.
And he suggested, I read this book by Corson, so I got the book by course, and,
and I found it completely incomprehensible.
Just, I mean it was a fascinating book cause it, it was very comprehensive.
It described all of these different spins fields and different things like that and
using a lot of two components, spinners, which is the right way to do it.
But.
To introduce what these objects were, was almost incomprehensible.
I found, mainly because you have these translation symbols all over the place and
they mess up the appearance of the formula.
So I just found this thing very complicated and in comprehensible, but
then I went to directs.
Second course.
It may have been not the same year.
I think he went one year.
I did the first, and maybe the second course was when I was a research fellow
rather than when I was a graduate student.
I can't quite remember.
I think must've been when I was a graduate research fellow.
Anyway, he, this was a course on quantum field theory and things like that, but he
sort of deviated from his normal.
Uh, course in one week to talk about two components, minutes and fame.
For me, this was exactly what I needed.
It made the whole subject clear from this complete confusion that I had before.
Now, then you see, many years later, I talked to Graham Fama and I told him the
story.
And you said, that's very strange.
Durag would never deviate from his course.
He just, he thought, well, when are you going to this course?
Perfect.
It was perfect.
He would never change, and this was true of his first.
Yeah, of course.
The shorter the initial course, which I went to.
Which people often said to me, well, that it's not such a great course.
It's exactly like his book, but it hadn't read this book.
So to me, this was, sure, the book is amazing too, but not having read the book,
I found this course absolutely stunning on it and made things up.
Do you
Eric Weinstein: think Dereck actually understand, understood these objects is
most mysterious of all
Sir Roger Penrose: components, spinners.
Eric Weinstein: Spinners in general.
I mean, he brought them into physics.
They'd been previously found inside of mathematics, I think, by people like
killing and Lee or, I'm not sure who, but
Sir Roger Penrose: Katana
Eric Weinstein: cartoon perhaps.
I don't think, I mean, let me throw out a really dangerous idea.
I don't think any of us understand them at all.
And the part of the problem was, is that he understood very well what could be said
about them, but that, you know, I asked you before about like your favorite film,
you said 2001.
You could make an argument that spinners are in mathematics and physics, like the
monolith.
It's always encountered.
Nobody ever understands exactly what it means, but it always grabs your attention
because it seems so absolutely bizarre and highly conserved.
Sir Roger Penrose: Well, I always like to think of things geometrically and.
At least for the two component ones.
You see, when you go up to higher dimensions, you still have spinners about
the spinners.
The dimension of the spinners goes up exponentially.
So each time you add the two to the dimension of the space and the dimension
of the spin is this multiplied by two.
So
Eric Weinstein: think I mentioned two D for example.
Yeah.
You'd get spinners of dimension two to the D over two.
Sir Roger Penrose: That's the sort of thing.
That's right.
And so they, they.
Well, the usually mines talks about the direct spinners, which are the Fordham,
the fog, the full
Eric Weinstein: minutes.
Sir Roger Penrose: But they split into these two, two, and two.
Eric Weinstein: And even dimensions.
Sir Roger Penrose: Yes, that's right.
And even dimensions.
And, uh, I like to understand these things geometrically.
So you could see, well, the two components spinner represented, and I had this
picture of a.
Of a flag.
So you have the flagpole goes along the light cone.
So that's a,
Eric Weinstein: that's the vector like piece of it.
Sir Roger Penrose: Yeah, it's Avec.
Eric Weinstein: Uh, now you have an extra piece of date,
Sir Roger Penrose: an extra piece, which is this flag plane, and you get a pretty
good geometrical understanding.
They want a little catch to it.
Is that if you rotate it through.
103 hundred 60 degrees.
So you might think just to where it started.
It's not the same as it was before.
It's, it's changed sign and then you rotate it again.
Eric Weinstein: So that won't make any sense to anyone.
But if, I mean, one way of looking at that is if you have a Klein bottle for those
of, some people will be listening to this in audio as I'm watching it and video
Klein bottle in a certain sense that can be made precise, has the square root.
That would be a Taurus.
That is a double cover.
So it seems like a very weird thing to take a square root of a strange
topological Mobius like object.
But there you are.
Yeah.
So it's really the square root of the rotations that has this double effect, but
we say it linguistically in a way that makes it almost impossible for anyone to
Sir Roger Penrose: understand.
This is a mystery.
I mean, I understood that spin.
I was the square root of a vector.
Let's see.
And I couldn't make head or tail of that idea.
And it was, when I went to directs course, it did become clear.
And he made, he gave this very impressive illustration, which I thought was due to
rock.
I learned later it was due to human vile that you imagine a cone circular cones
space, like that circular cross section and another equal cone, which rolls on it.
So one is fixed and the other one rolls around on it.
Now you see, when you imagine initially the cone is almost, it's just this little
spike.
I mean, you've got a tiny circle at the end, and when you row one on the other,
it's like really one coin on the other coin.
So, and you can see when you roll one coin another coin, it goes round twice because
720 degrees as you're going around.
Okay.
Now when you imagine gradually increasing.
The angle, the semi angle of the cone.
And do you do it again?
You keep thinking of that motion until it becomes almost flat.
And then what's the other one?
It's just a little wobble, right?
So when it becomes flat, this motion goes to nothing.
So this illustrates how a rotation through four PI, two complete rotations, gradually
it can be deformed into no rotation at all.
However, with single rotation, it doesn't disappear.
Well,
Eric Weinstein: I think with a, with a police system in a wheel, we don't have
any trouble imagining a wheel that rotates twice as fast, half as fast, not at all
hooked up to one particular crank wheel.
Right.
The problem comes when.
Um, that, that's not the generic case.
The generic cases usually encountered one dimension higher three and up has a
familiar, because something called the fundamental group as it's structured in
the mod to, um, rather than the Z in dimension two.
So there is something where in the place where you can see this most easily, it's
slightly misleading.
And then.
In higher dimensions, you have to learn how to tutor your intuition, which is this
problem that all of us who try to think about higher dimensional objects and
counters that we have to use, the visual cortex we're handed, and then we have to
trick it into imagining worlds beyond where we've seen.
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Sir Roger Penrose: Then you see, Dereck had another thing that's I . Uh, there's a
thing called the direct scissors problem.
So you imagine a chair with which has the, um, pieces of wood going out like this,
and you have a, a pair of scissors.
I think this is directs the joke that Jane was a pair of scissors and through the,
when you put your fingers, you have a piece of string which goes through this,
and then it goes around the chair and then comes back through.
The other one goes back again.
Right now, the problem is you take the scissors and you rotate them.
Eric Weinstein: Through three
Sir Roger Penrose: 6,360 degrees and the strings all tangled up.
We
Eric Weinstein: can't,
Sir Roger Penrose: and whatever you do, you kind of untangle it.
You're allowed to move assistance around parallel, not rotate them, and you can
move the string around it and you can't undo it, but you do twice, 306.
For 720 degrees, two complete rotations, and then you find you can untangle it.
So this was the direct scissors problem.
And I think that the, the joke was, it's a pair of scissors, so if you get too
frustrated, you just . And he wrote a paper explaining that I think max
Eric Weinstein: Newman.
Yeah.
Sir Roger Penrose: Wrote a paper.
Dirac did this illustration how you can undo it when it's, when it's.
Right for a PI for feminine trainees degrees, but to prove that you couldn't do
it with this is I think max Newman head.
Eric Weinstein: If you've seen this video called air on the Dirac string, which
illustrates this in video form and scene, I would highly recommend it because it, it
shows this off, is the similarity to the belt.
Tricked the Philippine wineglass and all different versions.
Yeah,
Sir Roger Penrose: I find that I could do that one.
Actually,
Eric Weinstein: I had Joe Rogan try it and I think he got almost all the way around.
Yeah,
Sir Roger Penrose: no, I have, I've done it with a Glassman.
Yes, you could like that.
And it comes back.
Eric Weinstein: Very stylish.
Yes.
So you can do
Sir Roger Penrose: two, two complete rotations, complete rotation.
Eric Weinstein: So this is a very fundamental property of the world that is
somehow not discussed.
I think I find it very interesting that people want to talk to me about the
multiverse.
Sometimes they want to talk to me, but quantum measurement problem.
But the idea that we are somehow based on a square root, and I would disagree with
you slightly if you would permit it, that it's not just a question of the square
root of the.
Of the vectors.
It's a square root of the, the algebra generated by the vectors that really the S
the spinners are this exterior or Clifford algebra.
This object has fascinated me my entire life, and it's very strange that all of
you know the stability of matter and, and matters.
Strange properties with electron shells are all coming out of this weird, not that
it appears everywhere in the universe, and it's not universally known that it's even
there.
Yeah.
I
Sir Roger Penrose: suppose the difference between the family islands in the Bose
ones, so the particles which have a spin, which is.
Half an odd number, right, which, which have this curious property that you rotate
them and they get back to manage themselves.
And it's crucial for for Matta because the exclusion principle depends on the, the
family statistics, which is to do with the, this exact, this property
Eric Weinstein: does not edness and the scissor trick or whatever you want to call
it.
We wouldn't have a periodic table.
And chemical elements.
You
Sir Roger Penrose: wouldn't have anything.
We'd have anything.
Yeah.
You wouldn't have it.
You wouldn't have fermions in.
Otherwise you wouldn't have things which have an exclusion principle.
So, and the Bose ons, which are the opposite, they, they like to be on the, if
you have.
To Bose ons, you can have them in the same state and they rather like to be in the
same state.
So you get these things called Bose-Einstein condensates where you're
getting them very cool.
They all flop together into the same state.
But for the family ons, it's completely the opposite.
They hate to be in the same state where they can't be, and this is what sort of
pushes them apart.
So you've got the family principle.
Eric Weinstein: So you have this strange thing called the spin statistics theory
that says that if things have a nodded ness of a particular kind, then they
either are highly individualistic or highly communistic, whatever you want to
call it.
My question would be, there's another aspect of that that I've been very curious
about, which is when we have to treat these objects quantum mechanically, and
you've of course thought a great deal about quantum theory, we have two totally
different prescriptions.
For how to make these different objects, quantum mechanical, but there's a
one-to-one correspondence between these two utterly different treatments that
matter in force.
Get quantum mechanically.
It's the darndest thing
Sir Roger Penrose: when you get these two kinds of . Popsicle are two kinds of
Athens suppose ons and the family owns, and it has to do with the make a complete
rotation.
Do they come back to themselves or do they come back to minus?
And so
Eric Weinstein: that's the top logic.
Yeah.
But then there's this whole thing.
You go under Verizon integration, which is no integration at all.
I mean, you're, you're effectively almost lying about what you're doing to the, from
to make them look like.
Bose ons.
And yet what we, what we seem to get out of this is that nobody, I don't think
anyone could have anticipated that there would be a dictionary of two totally
different structures, which are seems to be almost word for word.
Sir Roger Penrose: And it's because they're not totally different in the sense
that you take two to ferry out and system and you got the both zones.
So you have the same load.
Yes, that's right.
Now.
Eric Weinstein: Yeah.
Maybe I could ask you a little bit about that.
Um, so I want to get to supersymmetry, but before I do,
Sir Roger Penrose: I see.
Yes.
Okay.
Go on.
Eric Weinstein: We're going to make you work this morning, so
Sir Roger Penrose: I can understand
Eric Weinstein: that.
Yeah.
Um, so here, here's my question.
Am I correct that you've lived through two errors, an era of fairly rapid development
in testable fundamental physics.
Coming from theory, I've tried to be very careful about setting that up so I don't
walk into a trap and a stagnant theory, uh, era in which theoretical predictions
coming, uh, at the level of fundamental theory have not been rapidly confirmed.
Um, by experiment.
Yeah.
Sir Roger Penrose: Thinking of things like string theory,
Eric Weinstein: I'm thinking about a regime before the early seventies and a
regime following the
Sir Roger Penrose: earliest stuff.
Super symmetry.
Is that what you meant?
Well,
Eric Weinstein: it could be grand unified theory, super symmetry, Technicolor.
It could be as some X, D it could be any one of a number of speculative theories
from Luke, quantum gravity, Reggie
Sir Roger Penrose: calculus.
Nice drink area.
It's like
Eric Weinstein: the kitchen sink.
We've tried a million different things that don't.
Sir Roger Penrose: Yeah.
It didn't really pan out, you mean?
Eric Weinstein: Well, it seems like, well, if you'll permit, uh, an American
metaphor, um, we've been waved into third base and we've been waiting for the signal
to come home for about 50 years, and we're not even sure that anyone's still, uh, you
know, they're at home plate.
Sir Roger Penrose: Well, you see, you might be wrong playing the wrong game.
That's the trouble.
Eric Weinstein: You think rounders would do it?
Sir Roger Penrose: Well, I mean, there's a lot of intriguing ideas you mentioned.
Basically, I think you were hinting it.
Super symmetry is one of them, which
Eric Weinstein: maybe I've thrown off close to 10 I pre prop.
I could do it pretty easily,
Sir Roger Penrose: but I guess you hadn't, there's nothing new about that.
They were, the people were playing around with.
Not something I'm Kelvin with the idea that not smart
Eric Weinstein: be at the basis of particle identity.
Sir Roger Penrose: Yeah.
Yeah.
I mean, these ideas come back again in a different form, but certainly in the, I
guess the 19th century people were playing with, well, I guess you can go back
further than that.
Phlogiston well,
Eric Weinstein: that's true, but I would say that Maxwell.
Was the first great condensation of a theoretical ideas where an enormous amount
of theory surrounding magnetism, electricity, visible light, invisible
light,
Sir Roger Penrose: that was a huge, huge
Eric Weinstein: revolution.
And that all of those things now, um, can be unpacked from a single geometric
equation
Sir Roger Penrose: that that's the thing.
I mean, people know about Galileo, they know about Newton.
I know about Keppra.
They know about Einstein, and they may know about some, the modern quantum field
theory, Heisenberg, Schrodinger people.
How many people know about Maxwell?
Eric Weinstein: Not enough.
Sir Roger Penrose: Not enough.
Eric Weinstein: Although the do have Maxwell's equations tattooed on their
backsides.
Sir Roger Penrose: Let some people do that.
That sort of general public don't know about maximum, but Maxwell's equations
completely.
Change our way of looking at the world and, uh, we live off it without thinking,
you know, you've got these lights here.
Well, these are visible lies.
So we, we know you knew about visible light, but we didn't know anything about
x-rays, x-rays, radio waves, they're all part of the same scheme, electromagnetism,
dynamo.
Well, some of this goes back to Farah day, just before max shore.
So Faraday had a lot of the influential ideas, electromagnetism.
Well.
Well, a little bit of that was known before.
Erstad knew that if you had an electric current, then you guys are magnetic field.
But it was the other way around with Maxwell know, if you have a varying
magnetic field, you're going to current and you combine these ideas, you can make
a dynamo.
So these, these things go to Faraday and he had sort of clues that there might be
some connection with.
Right.
But he didn't have the equations.
Eric Weinstein: But even max, you know, I'm very partial to this book on orchids
that followed Darwin's origin of species.
And it was the book he wrote, the title is, uh, and I always, I love reciting it.
It's, uh, on the various contrivances by which British and foreign orchids are
fertilized by insects.
And so you think, well, why would he write a damn fool book like that after origin of
species?
And the answer is he wanted to.
Test whether he understood his own theory, and in fact it's revealed that he didn't
understand the full implications.
I would say that the same thing is true of Maxwell's equations, which is, this is
perhaps the best dress rehearsal for unification we've ever seen.
You know, full unification.
And on the other hand.
It's not until the late fifties that we actually unpack the last trivial
consequence of the theory with the this bizarre effect of passing an electron beam
around an insulated.
A wire
Sir Roger Penrose: had enough.
Eric Weinstein: Yeah.
In fact, we, we had dinner last night.
We, we asked yacker Aronoff, uh, if he wanted to come, but he's in Israel and he
sends his regards,
Sir Roger Penrose: send mine back.
We will do it.
He's great fun.
I always,
Eric Weinstein: but that was a, that was a very weird thing where we learned that,
um, if you have, uh, an insulated solenoid that the.
Phase of the electron beam going in a circle around it would be shifted despite
the fact that the electromagnetic field could be treated as zero because the
electromagnetic potential, this precursor turned out to carry the actual content
that it.
Before that, it had been thought that that was just a sort of a convenience product
to recover electromagnetism, and it turned out that that geometric object was more
important.
And you know, in part, the reason I bring this up is that we would have no way of
visualizing this effect if it were not for your interaction with MC Escher.
Sir Roger Penrose: And now you have to explain that one.
Well,
Eric Weinstein: you know this, this, this etching called ascending and descending,
which is sometimes referred to as the Penrose stairs.
Sir Roger Penrose: Yes.
Well, you want that story.
Eric Weinstein: Well, I do, but yeah.
What I was going to say about why I'm asking.
Yeah, yeah.
Is that the photon is really best represented in some sense.
As the angles of a set of stairs like that with this very mysterious property that
what you're really talking about is what we would call horizontal sub spaces.
Picture to stairs, and the fact that there's a paradox of going around and you
seem to be going up all the time, but you're back to where you came is the same
thing as saying, I never go up and yet I come back higher or lower.
And that's called Hala OMI.
And we don't have a means of visualizing that except for like either rock, paper,
scissors, or your work with ushers.
Is that a fair comment?
Sir Roger Penrose: Well, I had, I mean, is
Eric Weinstein: it, cause this is the first time you've ever heard somebody say
this?
Sir Roger Penrose: Well, let me, I mean, there's a quick complicated story here.
You see, when I was a graduate student in Cambridge, um, I think it was in my second
year when the international Congress of mathematicians took place in Amsterdam.
And so I, and a few friends decided that we would go to this meeting.
And I remember, uh, I think I was just about to get on the bus or a tram or
something.
And Sean Wiley, who was a lecturer, and.
In the algebraic topology, um, just, just about to get off the bus, I was getting
on, he had this catalog in his hand of, uh, an exhibition and the van crock
museum, and this was a picture.
It the, the one called night and day with birds flying on.
Huh.
In into the day and the nights.
And they, cha cha Lubbers change into the spaces between the birds one week.
And I look at this, I've had some amazing, what is that?
Where did that come from?
You know, well, there's, you'd be very interested.
This is this, uh, in the fine art museum.
There is this exhibition by an artist called Essure.
So I'd never heard of him before, and I went to this exhibition and I was
absolutely blown away.
I thought it was most amazing thing.
I remember particularly the one called relativity where people walk up the
stairs, gravity directions in two different ways.
And I thought this was hugely impressive, and I went away thinking, well, I'd like
to do something impossible.
You see?
And I didn't.
See, I had an idea about an impossible structure with bridges and roads and
things like that, so it locally makes sense.
But as a whole, it was inconsistent.
And I didn't think I'd seen anything quite like that in his exhibition.
So I played around with this, and then I sort of whittled it down to the triangle,
which people refer to as the tri-bar.
So it's.
Triangle, which is locally, completely consistent picture, but as a whole, it's
impossible.
And I showed this to my father and then he started drawing impossible buildings, and
then he came up with this staircase.
So we decided we'd like to write a paper together on this, and we had no idea.
Well, the subject was, I mean, w w who sent the paper like this to what journal.
So he decided, since he knew the editor of the British journal of psychology and he
thought he'd be able to get through, we decided the subject was psychology.
Of course, it's, as you say, it's not, it's more in a way mathematics because
it's illustrates ideas well of co homology.
And other things like that, which, which, uh, I didn't quite know I was illustrating
at the time.
But anyway, he wrote this paper and, uh, we gave.
Some reference to ESHA, I think reference to the catalog.
And my father sent a copy to a friend, a Dutch friend who says, and the managed to
get the tuition.
And then my father, a national had a correspondence.
Um,
Eric Weinstein: so that was Lionel pen.
Sir Roger Penrose: No, no, no.
My family lounger.
Pen Rose.
Yes.
By the time I actually visited usher then, and.
And, um, he had sent to print to my father with a dedication to it, and he gave me
another, so I don't have the Bodleian,
Eric Weinstein: but
Sir Roger Penrose: in some sense, I actually had it in a museum.
Eric Weinstein: Is that I'm very indebted to you for this, for this reason, because
when I, when I have to describe what general relativity is, yeah.
And I don't wish to lie the way everyone else lies.
From an alignment and do it differently.
I say that you have to begin with four degrees of freedom, and then you have to
put rulers and protractors, uh, into that system so that you can measure length and
angle that gives rise miraculously to a derivative operator that measures rise
over run.
That rise is measured from a reference level.
Those reference levels don't knit together and they form Penrose stairs and the
degree of or Penrose.
Snus is what is measured by the curvature tensor, which breaks into three pieces.
You throw one of them away called the vial curvature, and you readjust the
proportions of the other two and you set that equal to the amount of stuff.
Now that's a very long causal chain, but it is linguistically and accurate
description of what general relativity actually is.
Sir Roger Penrose: Yeah.
What is it?
Let's stretch that.
It's also illustrates comb ology, which I was being interviewed.
Oh, ages ago, but I don't know whether it was BBC.
I can't remember what it was.
There was an interview, but for some reason they were interested in twists a
theory.
Now
Eric Weinstein: they think they're interested.
Sir Roger Penrose: Well, they thought they were, I guess they'd heard that word or
something.
And at one point they say, well, surprisingly not at the beginning.
They asked me what, what good it was.
You see, what can you use it for?
So I said, Oh, you can use it to solve Maxwell's equations.
You said, that's equations of electricity and magnetism and lights.
And so they got a bit interested and they said, Oh, well how'd you do that?
Well.
It's actually involves an idea that I couldn't really explain here.
It's, it's not possible to, in a, in a sort of popular talk like this.
No, no.
What is it exactly?
No, no, no.
I couldn't do it.
No.
What's the, it's an idea.
It's a thing called pomology.
No, I could explain that.
So then I went back home and I was lying.
My benefits.
I think I can't, you know, it's this impossible try.
And that's exactly it.
And illustration of . So I went back the next day and told them that they weren't
interested.
They didn't use it.
I think I may have tried to explain.
Yeah.
Where you have a little something which is locally consistent, but with an ambiguity
about it.
So here the ambiguity is you're not quite sure.
You draw a picture of it.
The ambiguity is that you don't know how far away it is.
It could be bigger and further away, or smaller and closer, and the picture was
consistent.
But you get an inconsistency if you go around locally because you have a freedom.
Yes.
And you misuse this freedom in a sense.
So the glitch in it is this impossible structure.
Well,
Eric Weinstein: I had this, so this is actually my son and my 14 year old son's
copy of that book.
Yes.
And I was having to describe this.
To him, Cole would call him ology was, and I said, yeah.
Um, that one forms, which is a piece of technology, uh, in mathematics that you
can analogize to radar guns so that while you're driving in, the policeman shoots
your car with the radar gun.
He's measuring the component of speed in the direction of his gun.
And so that's something that eats the vector of speed and spits out a number.
And then you could imagine it a racetrack.
That wanted to have a circular.
A series of radar guns to measure the speed of cars going around.
Now the question is, you also recognize that you could build a poor man's version
of a speed system by heating the track to some temperature and measuring how quickly
the temperature changes.
The car went over, but you can't actually have the one thing that you want, which is
the series of radar guns that are always measuring.
The speed going around the track, because at some point, if the temperature is going
down, down, down, down, down, down, down, then it's going to be 10 degrees below
wherever it started.
Which is your paradox again.
Sir Roger Penrose: Yes.
Well, that's a nice example.
Somebody may remember who, where you accompany, you have a bowl going up the
stairs or down at whichever it is, and you accompany that with it.
Uh, a note going up or down.
And you can make it sound as though it keeps on going all the way up and all the
way up all the time.
I, by the harmonics, you bring a new home only can as you go around
Eric Weinstein: below and sub perceptual.
So there, there's this auditory illusion that captures these.
Yes, you've have an
Sir Roger Penrose: auditory version at the same thing.
It's something you had this bowl bouncing around with that.
Eric Weinstein: That's not real.
But that's a bit of a cheat.
I mean, my point would be that your S your stairs or your Penrose stairs.
Are the, the cheat is that it appears to be flat.
In other words, it's very easy to achieve that on a curved object, but that what you
did was to create the illusion as taking place in a plane.
Or
Sir Roger Penrose: maybe you can George in
Eric Weinstein: the linear system,
Sir Roger Penrose: do you have an interpretation of a three dimensional
thing, which, which in an ambiguous,
Eric Weinstein: and so you saw the movie inception of course, where they.
They realize that this actually,
Sir Roger Penrose: yes, they're there.
They have an illustration of that there.
That's right.
Yeah.
Eric Weinstein: But that effect is the soul of the Aronoff Boehm effect, which
surprised the world in the late fifties because it was discovered so late into the
game.
Sir Roger Penrose: It's just a, it's just a company.
Same sort of thing.
That's right.
Well, of course, like so many things people point out that.
This Oscar righteous fart who was a, who was a Swedish artist that drawn things
like this before.
I think roundabout the year I was born, he had a picture, which is all with cubes
going around.
It wasn't exactly the same, but it was,
Eric Weinstein: I think I've seen these floaters.
Sir Roger Penrose: The cubes, yes, but then he had versions with stairs.
Staircases too.
Well, let me never put any, he never put any perspective in it.
We seem to me that was a
Eric Weinstein: something missed opportunity.
Yes.
Sir Roger Penrose: No.
And my triangle, I did put some perspective.
Yeah.
So there's slightly, you can see, but you can do it with the perspective and it's
still still works.
Eric Weinstein: So what I want to get at is.
I think also that we have this very funny thing that happened recently is starting
from the early seventies where we started miss telling our own physics history
because of the needs of the community to look like we were succeeding when we
weren't, or we were succeeding at something different than we were trying to
succeed at.
And.
In part, one of the reasons that I want to use this podcast to discuss science is to
give alternate versions of what's happened, and I want to explore one or two
of them with you.
Now, you and I have a very funny relationship, which we don't really know
each other, but you were quite close to Michael the T at various points.
And I was,
Sir Roger Penrose: well, we have graduate students again, and the same in the same
group,
Eric Weinstein: same year,
Sir Roger Penrose: absolutely.
Same year.
They asked me the same supervisor.
Incredible.
Yes, that's right.
Eric Weinstein: And then you continue to cross pollinate ideas.
Yes.
That's for the years.
Sir Roger Penrose: For,
Eric Weinstein: for listeners who don't know, Michael was one of the absolutely,
most dominant and generative.
Um.
I don't even know what to call him.
Like beyond genius, a seer of type.
Sir Roger Penrose: When he sh she had such a broad understanding of mathematics.
It's partly
Eric Weinstein: in geometry or generally and analysis.
I, we just credible and algebra.
I mean, he wrote a book on, on communitive algebra, the, um, now he had a partner.
Uh, for much of his career is adore singer who I was quite close to for a period of
time.
And his was, again, another one of these figures that if I'd never met one, I
wouldn't know that the human mind was capable of that level of repeated insight.
Yeah.
And they came up with something called the singer index theorem, which governs worlds
in which there are no time dimensions, but only space dimensions or no space
dimensions and only time dimensions, but there's
Sir Roger Penrose: no just equations without any differential equations.
Eric Weinstein: Differential equations, if you think about differential equations, is
coming very often.
Three main fields of study, elliptic, hyperbolic and parabolic.
Then the idea is that wave equations would be hyperbolic, the type that you're
worried about in physics, but things like soap films look like elliptic equations
and TN singer had this incredible insight into the nature of elliptic equations.
Do you think.
Sir Roger Penrose: Yeah, go ahead.
Sorry.
No, I was going to say it's extremely general theorem, which covers goes over
all sorts of different areas of mathematics and it has application.
It
Eric Weinstein: sort of tells you that the.
The nodded of some beautiful space that you might be exploring, like some kind of
high dimensional donut that's nodded many times around itself.
Whatever you want that that top a logical nodded Ignace tells you something about
the kinds of waves that can dance on that space.
Sir Roger Penrose: Yeah, no, I see.
It's very remarkable.
Theorem
Eric Weinstein: does that theorem.
In the so called elliptic category, a world of space and no time.
Let's say relate strongly in your estimation to the most important
hyperbolic equations that govern the waves that make up our physical world due to the
constraints of relativity in a world with one time and three spatial
Sir Roger Penrose: dimensions.
I can say if I use the therapy.
And at least two different con contexts.
Yes.
Maybe more so.
I mean, I'm not an expert in that area at all.
And it was mainly, yeah, when I was trying to, um, I shouldn't have turned that
option though.
I was trying to, uh, solve a particular problem.
I don't know how much detail you want to go into these things.
It had to do with, um.
How to make to a Safari work in curved spaces.
But I ran up into a question
which had to do, how do I put this?
It has to do with complex geometry.
So you've got geometry in which instead of using.
Real numbers to use.
You think of measuring with rulers, say and the re the ruler is one dimensional.
The numbers go along one dimension, if you like, and complex numbers where you have
the square root of minus one incorporated into the number system.
They're really two dimensional.
So the, the geometry of complex numbers has twice as many as the real numbers, but
the geometry of complex numbers.
Is particularly fascinating or not the algae, or you might say the analysis or
whatever it is.
It's particularly fascinating.
And I was sort of, when I learned about this when I was at, um, an undergraduate
doing mathematics, and I thought it was an incredibly beautiful, because when you
talk about real numbers, you have, um, you can have a second draw co, which is a
function.
So this, this curve has some shape.
And you might want to see what is it a smooth curve.
That means you have a tangent direction as you go around it.
Maybe it jumps so it's not even continuous or maybe smooth, or it may be you have to
have a curvature of this curve and you might, might not be smooth enough to have
curvature.
See if there's one degree of smoothness or two degrees or you, or you can have three
degrees or four degrees and they're all different or an infinite number of
degrees.
Or that you can expand your function in the power series.
They're all different.
And then we learned about complex.
You see, Oh, we not do it all over again.
And you've got your analysis on algebra.
If you like geometry worthy, it uses complex numbers, and then suddenly you
find that if it's smooth.
Everything comes with it.
You can differentiate as many times as you like.
You can expand as the power series, and I thought, that's incredible.
Re magic.
You just have to do it once rather than this old Craig.
All these different kinds of
Eric Weinstein: mathematicians.
Sir Roger Penrose: Yes.
Eric Weinstein: Quite often view the complex case, the ne the case of complex
numbers as the natural case and the case of real numbers as artificially tortured.
Yes.
Which is a complete reversal from how most engineers and physicists and us actually
have been quite instrumental.
In making the case for the fundamentally complex nature, that it's not just a
convenience that we use complex numbers in physics, but that nature appears to be
essentially complex.
Sir Roger Penrose: I think you see, by just hearing this nature of complex
analysis and how beautiful it struck me as being, and I had this sort of feeling,
wouldn't they be wonderful if these numbers were somehow the basis of way.
Physical world operates.
I have no reason to think that.
And then I learned about quantum mechanics and I was maze to find.
Yeah, there they are.
They're not just useful convenience.
You can use them to simplify ideas and mathematics.
You can, you know, might have an integral,
Eric Weinstein: you would have to work awfully hard to get rid of.
Sir Roger Penrose: Yes.
But there are things, you find that you're a little trick to do it.
You know, these four to me come.
With continental goals and they'd drop us in an amazing way.
And I thought, well, that's a piece of magic, but it doesn't tell you anything
about the world.
It just tells you this is a neat way of doing things.
And then on and on about quantum mechanics, and suddenly these numbers,
they're right there, the basis of the whole subject.
And I thought that was an amazing thing.
Maybe these complex numbers are already there at the root of everything.
Eric Weinstein: Now, one of the ways of describing what twister theory is, and of
course it's a, it's a bit of a tall order for a podcast, is that you are replacing
Einstein space time with a larger structure.
That inset in some sense implies space time, where you can take all the data that
roams around on space-time and the waves, the force.
The matter what have you, and you can, as mathematicians might say, pull it upstairs
to this larger twister space where you might have a couple of extra tricks up
your sleeve because the extra space that you've created to augment space time with
has this.
Kind of complex number aspect baked into it.
Sir Roger Penrose: Yes.
Really, it was something I just to go back for a moment to explain the a T a
signature and that's why it was useful to come to Latin minute because it's, it's a
very interesting story.
The way these things sort of come together and take many, many years sometimes for
what they come together.
But I was really intrigued by these complex numbers and there is.
Well something.
Let me tell you, it was sort of the origin of the twists or idea.
I was struck by the fact that you see, people know that
when things travel with a great speed and in, in according to.
Einstein special relativity.
They get sort of flattened in the direction of motion.
Now this is a way of talking about it and you get this Lawrence contraction as it's
called now, I was playing around with a relativity and thinking about it was this
two two components, spinners and thinking of how the geometry of it worked, and I
realized if you think of the sky, you see the sky is is.
Where you have vectors in four dimensions.
Think of a vector or something which has a, has a, a magnitude in the direction to
it as well.
And in ordinary three space, you've got this idea of a vector, which is quite
common to people know about.
But when you're in four dimensions, then you have.
Space and time together.
But do you have particular vectors which are called and these other ones along the
light cones?
So these, this is C, an ordinary vector might represent a velocity.
So you have a particle moving along with a certain speed and you know, four
dimensional vector would point along the.
Philosophy or the momentum of that particle.
So
Eric Weinstein: weirdly in the space time metric of Einstein, yeah.
These are vectors that are not zero, but if you used Einstein, special rulers and
protractors, what would the length of these
Sir Roger Penrose: vectors?
Eric Weinstein: So, so it's a really, it's a, it's linguistically tricky to talk
about these things because they're nonzero things that would be measured to be zero
length.
If that concept of length was in fact, um, yeah.
Extended from your normal concept of like,
Sir Roger Penrose: yes, the idea that something of length zero means it's two
points.
The distance between them, a zero you think of them ran on top of each other, or
if the distance is very, very small, they're pretty close to each other.
But in the kind of geometry, we'll call it Midkowski geometry, cause although it's
describing and science special relativity.
The gym geometry was not an Einstein.
People often say, Oh, well, Einstein introduced as four dimensional space time.
That's not true.
It was Makowski.
And I said, son,
Eric Weinstein: this is real.
This is not just a sort of a weird artifact of, uh, the description of, um,
various processes that were being entertained.
Sir Roger Penrose: It's a kind of geometry and Makowski showed that the.
The space of special relativity is really four-dimensional, and it's this kind of
geometry in which you can have distances, which is zero.
Although the points are sort of long way away from each other, and this represents
a light Ray.
So you'd have one event say, and then the light through that vent reaches another
event.
When I say event, I mean not just as special.
Position, but at the time as well.
So
Eric Weinstein: you mean position in space,
Sir Roger Penrose: time, space, time.
So you need four coordinates, three space in, one time.
Coordinate.
So that's when we call them an event.
And so you have a point or an event in space time and managing the particle moon
of the speed of light to another such event.
Now the distance between those two in this kind of geometry that min Kafka introduced
is zero.
So, and he made Kosky played around with different kinds of geometry, and he
realized that special relativity is really best described by this kind of what we
call Makowski and geometry.
So you can have zero distances and yet the points are not on top of each other.
Eric Weinstein: So your idea was to take all the points that are bizarrely zero
distance away and then make those the new points in a new space.
Sir Roger Penrose: Well, it wasn't quite that I have, I, I, I had to come up to
this slowly because it took years.
But the initial idea isn't so hard to understand really.
You see, if you look out at the sky, what do you see when you're seeing light rays
or you're seeing photons coming to your eye, which have traveled with the speed of
light.
So the world line in four dimensions of that photon is.
T tilted over at what represents the speed of light.
Now in this Makowski geometry, that distance has a clear meaning.
So let me, let me give that the.
Supposedly the photon is emitted at one point, one event, and received as another
event.
Now to that photon, the time between one and the other is zero and that time
measure is exactly the distance measure.
In Minkovski geometry.
Suppose the Popsicle was not traveling at the speed of light.
Suppose it traveled with half the speed of light or some other speed.
Then.
It's time.
Experience of time is exactly the distance.
According to Minkovski is geometry.
So you say if it travels with very, very, very great speeds.
Suppose you travel to a planet, which is four light years away and you travel with
. I won't do the calculation right here, but with half the speed of light, then you
would the experience that you would.
Of time you experienced is less than the time that somebody here on earth would
think that it took you to get there.
So as you travel faster, you, your experience of the passage of time slows
down in a sense.
You don't think it's as long.
And if you actually travel the speed's blood, that experience would be zero.
So this is the experience of the length of time.
If you add weight, you could have a very, very good clock you carry with you and you
see how, what, how,
Eric Weinstein: how the clock made of pure light.
It all gets pretty, pretty heady out here.
Sir Roger Penrose: Well, you don't make enough.
You can imagine a clock, say a nuclear clock or something, and you're not
traveling with the speed of light because you can't get to this point.
But the time measured by that nuclear clock would be the distance in the cuffs.
Eric Weinstein: I should point out just for our listeners.
Yes.
People who do this field of a differential geometry morning, noon and night in math
departments almost never choose to work in worlds with some temporal and some spatial
dimension because it just, it breaks your head.
Sir Roger Penrose: It's a very difficult,
Eric Weinstein: different intuition, very different
Sir Roger Penrose: intuition.
You go back and you think about the puzzles that people had when Einstein
introduced is special and then most particularly general, I just have a T.
They find it very puzzling.
You could see, look at the arguments, people that,
Eric Weinstein: well, we keep using these words like time and length and all of
these things that have become, we, we don't recognize that in that one innocent
decision to break off one degree of freedom and treat it differently.
All of our linguistic intuition goes out
Sir Roger Penrose: without all over again.
Yeah.
Well, it was a curious experience I had because I was giving a series of lectures,
um, and Sappho it was, these were the Battelle lectures given in, what was it?
The, um.
I forget exactly what the dates were.
Maybe this roundabout nine 1970 or something like that.
And there was a collection of mathematicians in the collection,
physicist John Wheeler, and Cecile Dewitt to organize this.
It was a very interesting meeting.
Well, people from both areas of expertise were brought together and at that time,
it's hard to believe now, but at that time, mathematicians and physicists were
barely talking to each other.
And they got me to give a series of lectures, and
Eric Weinstein: this was before, um, Jim Simons and CN yang get together and
Sir Roger Penrose: there is a good question.
When was the, that
Eric Weinstein: was 75.
77 was before
Sir Roger Penrose: that.
Okay.
Wow.
Is that right?
I think so, yes.
I really have to, my memory is dates.
Eric Weinstein: I know you're, you're hot on the, on the trail of this, but just to,
to 11 something in Roman at MIT once beautifully said.
Um, and he, I don't think you wrote it down.
He said, we used, we didn't understand.
The partnership that was possible between mathematics and physics because we, the
physicists used to talk to the analysts and he said, the analysts either told us
things that were absolutely trivial and irrelevant or things that we already, he
said, when we talked to the geometers, we started to learn new things that we'd
never considered.
Sir Roger Penrose: Yes, well, it was trust quite very much cross fertilization there,
but I was going to say, I gave his lectures that I think it was 12 lectures
and I wasted my time on something that you weren't going to until I left myself.
Only three lectures to describe.
The singularities, the black hole idea, which wasn't the term black hole wasn't
used as then, but the collapse,
Eric Weinstein: which is called the Schwartz, Jill singulars.
Sir Roger Penrose: Well, it was called a singularity when it, that was thing,
people call it the swatch of singularity, where it's what we now call a horizon.
Right.
And I remember in my third lecture from the end describing the, basically what
work we call a black hole that's talking about the Schwab tshirts singularity.
And I was explaining that.
Yeah.
It was basically to do with the zero link business.
And Steen rod was a very distinguished mathematician.
He
Eric Weinstein: Norman steamroll.
Sir Roger Penrose: Yeah.
And he'd written this book on five of bundles, which is absolutely impenetrable.
Impenetrable, but also fundamental to the subject.
Eric Weinstein: Yes.
But it's so impenetrable that I never got to the point.
Sir Roger Penrose: But anyway, he was there at the back of the room and I
remember telling him about us, and he was absolutely dumbfounded.
They see you as somebody who's a real expert at this kind of geometry, Manny and
geometry, whatever you call it, where you have the notion of when the distance is a
small than the points are close together, and here you have this other kind of
geometry and the intuition you need for that geometry.
It's completely foreign.
It's the point you were just making
Eric Weinstein: because yeah, we do have this weird way of talking about something
that sounds like this.
We might call it like non Hausdorff topology, but it is a Hausdorff topology.
It's, it's, so the problem is, is it's pulling apart two different notions of the
word close.
Sir Roger Penrose: That's right.
Exactly.
Because you think of close means a small distance.
Right?
So you imagine a little tiny bowl where the distance from that point is
Eric Weinstein: small.
You know, mathematics makes you pay for every attempt to sort of intuitively
encode something that isn't precise.
Sir Roger Penrose: Yes.
Now I wanted to, I see, I got a bit distracted from leading up to the twist,
cause that was.
Well, I needed the complex numbers.
That's right.
I needed the Lorencia and, okay, we've got all that.
Yeah, I can do that.
Very good.
Yes.
So
Eric Weinstein: Roger, now we've w we've been discussing the fact that this
intuition is very, very strange involving how to think about, um, spaces of the type
that Einstein and Makowski and pong Correy were considering.
Yes.
How does that begin to lead us towards these a more speculative ideas of yours
surrounding complex numbers and the twister program?
I don't think many people, uh, many, many of them may have heard of it, but even in
a, even in mathematics, you have to know that you got, you were sort of seen as
leading edge.
Cult.
It had its own newsletter, its own bizarre drawings.
It was very difficult to communicate to members of the twister cult because they
didn't speak like other people
Sir Roger Penrose: where we had this twist newsletter, which was a, it started off
by, it's just in handwriting and it was duplicated and then that's not going to
that for the moment.
Very good.
Talk about the base, the origin of twists here.
If you're like, where did it come from?
It was really,
Eric Weinstein: in fact, your big bet in physics.
Do you think.
Sir Roger Penrose: Yeah, I think so.
Well, you see, it's between that and the cosmology, but the cosmology is a bit
different cause that's not such a, okay.
Wild idea.
Yeah.
But it's not a whole body of wild ideas, which twists the theory more is right.
Um, but it has lots of connections with mathematics as pure mathematics and
connections with physics.
Let me describe the basis of it, because I think we've got most of the things we
need.
You see the light cone.
Describes how from a one point to one event in space time, all the different
points of zero distance from it or another was all the light rays from that point.
Now,
let me think about it the other way around.
That is my past light cone.
So I'm sitting at a certain point in space time and I look out at the universe and
all the light rays that get to me at a particular instant.
Moment of my time come along this past like her.
So that's, you mentioned this stretching out into the past and getting bigger and
bigger as it goes back in time.
And that's all of the events, which are one moment of my time I was, I see those
events, so I see a lot of stars in the sky.
Now let's suppose that.
I mean the stars in the sky look like points.
You see, so that you have this sphere, the celestial sphere, which is my field
division.
If I'm imagining myself out in,
Eric Weinstein: so imagine that the earth was transparency.
You weren't, that's why my,
Sir Roger Penrose: Oh, just let's go out into space.
Then I can be looking at the world around me.
Now let's imagine that another astronauts comes whizzing past me at nearly the speed
of light.
And just as we pass each other, he looks, he or she looks out at the sky the same
moment as I do now because of a phenomenon known as aberration.
The stars will be slightly.
Not in the same place with regard to that astronauts as me.
Um, this guy is somewhat distorted, but it's distorted in a very particular way,
which is what's called conformal.
Two way.
Say this in a simple way, I suppose I happened to see a configuration of stars
that happened to be on a circle.
I suppose they were can cyclic cysts then this astronaut passing by me, we'd also
see these in a circle.
Even though the transformation would not be a rotation of the spheres, Skype would
be squashed up more on one end and stretched out at the other end.
But the thing about that transformation, it's something which I knew about from my
complex analysis days.
Do you think of the what's called the Raymond sphere?
This is the.
The plane of points is it's a complex plane or the vessel plane or the play.
The points represent the complex numbers.
So zero is in the middle if you like, and then you've got one and then you've got
minus oneN I and minus either all on the circle and you go out and infinity is way
out to infinity.
But the Raymond sphere folds all this up into a sphere.
So infinity is not point.
Eric Weinstein: This was a little bit like if you ever.
If you have a caramel coating around an Apple, you're folding that
Sir Roger Penrose: you floated around and
Eric Weinstein: at the point where the stick would go into the Apple, all of the.
Boundary of that, a candy would come together.
Sir Roger Penrose: Yes.
And it's what's called listeria graphic projection.
You can project from the North pole and all the other points flashing that until
the plane.
Eric Weinstein: So you can see all the points on the sphere except for the point
from which you're projecting.
Sir Roger Penrose: Exactly.
And that's called the steer read graphic projection.
And it has this remarkable property that it sends circles to circles, or you could
say it's conformal.
That is angles preserved.
And it's a very beautiful transmitter.
I used to play around with these things for fun often.
Now the thing is that the transformations of this sphere to itself, which preserve.
The angles.
It's also transformation, which is what's called analytical column, Hala morphic.
It's, it's the most smooth transformation.
You can have
Eric Weinstein: just the analog of smooth, but for complex objects rather than real
objects.
Real and complex means the types of numbers.
Sir Roger Penrose: Yes, that's right.
So what's what smooth is and complex analysis.
And those transformations which send the spheres and sphere are exactly those in
relativity.
So the . Different observers passing me at different speeds, looking at the same sky.
The map from my sky to their skies is exactly these complex transformations of
the sphere.
And this actually is what you exactly get when you use two components, spinners, and
you see the description when you move from one observer to another is exactly those
ones which transformed the sky in this conformal way to itself.
And.
Often people find this puzzling.
I find it puzzling originally because suppose you had a sphere which is
whizzing, you know, an alien spaceship, which is a sphere shooting past you at
nearly the speed of light.
Well, you see the direction of motion.
It will be.
Contracted by the Lorenz contraction.
So when you look at it, you should see it sort of flattened out.
You don't, because the sphere goes a circle.
It goes to a circle.
If you see it as a circle, when it's not moving, you will still see it as a circle.
I'm the boundary of the thing will look like a circle when it is moving and you
work away and think about it.
Well, you see where the lightweight is.
Go in the front of it and the back of it and all that, and you see really, you
don't see the flattening.
It really is, doesn't look like a, like I said, a circle.
It's boundary.
It looks like a cycle.
So I read a paper on this almost simultaneously.
There was somebody else who had a paper.
I'm mainly thinking of the small circles and spheres.
Um, but this transformation, that's really what started me off.
Eric Weinstein: If I understand correctly, maybe I don't.
Yeah.
Um, we have another mutual acquaintance, uh, or friend Raul bought, and yes, he
showed us that the world seems to repeat every eight dimensions in a certain way.
But during the first cycle of what you might call bot periodicity from zero to
seven or one to eight, depending on how you like to, can you get these things
called low dimensional coincidences and so that they don't.
Recur because of your point earlier about spinners that spinners grow exponentially,
whereas vectors grow linearly and, but during the first period where these things
are of comparable strength, yes, you get all of these, um, objects where depending
upon, you defined in two different contexts, you turn out to be the same
object you're making use of that.
Here
Sir Roger Penrose: it is that it's the, uh.
Well, the Lawrence group
Eric Weinstein: or like you know, that the rotations of space and time, which we
might call three or son three double cover, would be equal to something else
called SL to C, which would mention complex numbers, even though there's no
complex numbers to be seen in space and time.
Sir Roger Penrose: Yeah.
It depends on that.
One of those coincidences was triple coincidence, I think you said they got it.
Which one is depending upon, and this description, but the point I'm making here
is that it has certain sense relativity.
Is described when you do it in the two spinner form, which is really expressed in
this fact that it's the transformation of the Raymond sphere to itself, which is a
complex transformation.
This is the most general transformation of the sphere to itself.
When you think of that sphere as a Raymond sphere.
So it's a complex one dimensional space, you might say, surely it's two
dimensional.
Well, it's two dimensional in real numbers, but one dimensional in complex
numbers cause the complex, each complex numbers carries the information of two
real numbers.
Eric Weinstein: So for example, mathematicians would call what most people
call the complex plane.
They might call it a complex line.
Sir Roger Penrose: It's complex line.
That's right.
Eric Weinstein: Yeah.
And so the language, again, is intended to make things very hostile to the newbie.
Sir Roger Penrose: Yes, it's, that's true.
But you have to get used to the idea that when you're thinking complex, when you
think of it sort of really sort of concretely and in the real terms, that you
have to double the number of real dimensions to get the member of complex
Eric Weinstein: life.
I want my audience, but I don't want them to feel stupid for making a mistake that
everyone where a person,
Sir Roger Penrose: you have the number of course.
Yes.
So we have the.
Complex numbers playing a fundamental role in relativity.
That's really point they want to make, and it's the complex sphere, sorry, the remand
sphere, which is this one dimensional in in complex sense, two dimensional in the
real sense object, which is fundamental.
Now this Raymond sphere appears in the most basic way in quantum mechanics too.
You think of the, the spin now, that's the practically the most direct complex.
The most direct.
Quantum mechanical thing in a certain sense where you see quantum mechanics
playing a real role as quantum mechanics, which is hard to grasp normally, but you
can see it here.
It's the geometry reworks.
You see, if you have an object of spin, half, that's the smallest non-zero has
been.
You can have such an electron.
So think of an electron.
It hasn't been half now.
What that means is that it's basically two States of spin, which people call it spin
up and spin down.
Well, what does that mean?
Right?
Hey, put your thumb up like that.
Right-handed spin is where your fingers go, and that's.
Spin up means right-hand is about up.
Spin down is right-handed.
It's about Donna has left-handed amount up, and those are the two basic States.
But what's special about up and down?
Nothing.
So you think of what about right?
Left forwards, backwards, all those are combinations of happened down.
And are complex combinations through these complex numbers, which lie at the basis of
quantum mechanics.
But here you can see in a visual way what they're doing.
You see, you can say up down what's left and right where these are com combinations
of up and down.
So you add this much of up to that much of done and you get.
To the, to the right, and you minus it, you get to the left, I times you get
forwards, whichever it is.
And the complex numbers come in to describe these possible directions of
spin.
And it's the Raymond sphere again.
So.
But you were relating these complex numbers of quantum mechanics do the
directions in space, so you have a connection between these rather abstract
numbers, which are fundamental to quantum mechanics and the much more concrete
picture of directions in space.
Eric Weinstein: But Roger, I think you're both, well, let me be challenging slightly
ever so slightly.
Sir Roger Penrose: Go on.
Yes.
Eric Weinstein: What you're really talking about is a very important fork in the road
for physics.
Do you wed yourself to the world that we're actually given?
And you know, Mach was famous for having said this phrase, the world is given only
once.
And so we happen to know that there does exist a world.
That appears to be well modeled by three spacial and one temporal dimension net.
And then the key question is, do you wish to have a more general theory, which it
works in all dimensions or works works for all different divisions between how many
spacial and how many temporal dimensions?
And what I see you as having done, which I think is incredibly noble, brave, and
scientifically valid, is to work with mathematics that are really
Sir Roger Penrose: perfect.
Eric Weinstein: Particular Ising themselves to the world where given rather
than sort of keeping some kind of, I mean like you're getting married to the world
we live in, in a way that other people are just dating it and wishing to keep their
options open.
Sir Roger Penrose: I think you've hit on a very crucial point.
Absolutely.
Right.
I mean, for example, with string theory and all that, people talk about 26
dimensions or 10 special dominion or 11 or 12 and things like that, and sure, the
mathematics, we've got mathematics to handle these things, and maybe that's
important to the way the world works, but I was never attracted by that.
It's for basically two reasons.
One was the reason I'm just trying to subscribe here, and it's exactly what
you're saying, that I'm looking for a way in which.
You find a mathematics to describe the world, which is very particular to the
dimensionality we see.
So the three space dimensions and one time dimension.
Is described in this formalism very directly, and if you're crunch to try and
talk about other numbers of dimensions of space and time, it doesn't work
Eric Weinstein: as much as I really like to stick it to the string theory.
That's not exactly their problem either.
Because 26 is really, because it's two more than 24 and 10 is really because it's
two more than eight and an eight you have something special called
Yes.
And so what they were really doing was figuring out how to build different
theories around different highly specific
Sir Roger Penrose: targets.
But you see there, it's the beauty and the mathematics, which sure is a good guide,
but it has to be.
Well,
Eric Weinstein: they probably lose some weight.
The reason they never grow up to playing with reality.
Sir Roger Penrose: That's the sort of thing, I mean it's, it's perfectly good to
explore all these different things and it's very valuable.
But I'm trying to follow a route which is viewed, I think in many qualities is very
narrow.
I'm looking for a route which is work specifically for the number of space,
time, dimensions that we have and is.
If, I mean, there are aspects of choice theory, which do work in other dimensions,
but they run out very quickly and you can see analogs of these things, but they kind
of
Eric Weinstein: version of the anthropic principle, which is that if there weren't
a beautiful mathematics to, to catch you.
I mean in some sense, despite the fact that you're in your late eighties it's
like you're stage diving at a punk concert where you're kind of hope that the
mathematics catches you because you're willing to actually marry in a very deep
level.
The world.
That we do observe, and I find that what, what's very disturbing to me, um, is that
the political economy of science means that fewer people are willing to make
strong speculations, strong predictions.
To explore things that don't give them the flexibility in case things that don't work
out to say, um, well, it could be like this.
It could be like that.
And so in part, I see you as part of a dying breed of people who are willing to
go down with the ship for the privilege of commanding it as its captain.
Sir Roger Penrose: Well, you can use it that way if you like.
My claim is that the ship isn't actually sinking.
You might
Eric Weinstein: think you don't know.
No, I'm not.
I'm not claiming that.
I think that one of the things that that's happened is has been that yours has been
one of the most important idiosyncratic programs that in fact got a huge.
Lease on life from the fact that it has positive extra now and is because it was
absolutely solid mathematics.
It turned out that even if it doesn't give us a fundamental description of the world,
it is at least a deep insight into, um, how to transform one problem into another
to allow solutions that wouldn't have been easily gleaned in the first, in the
original formulation.
Sir Roger Penrose: Yeah.
Eric Weinstein: I'm not saying that it's, it's knocked out of the park for a
fundamental theory, but I, I don't actually know whether, do you believe
twisters are a more fundamental description of the world.
Sir Roger Penrose: Well, I do.
Yes.
I mean, I don't normally say that out loud, but now you've put me in a position.
Yes.
No, I do think that's
Eric Weinstein: fucking great.
I mean, in other words, it's like you have to say this, I believe in, in general,
people won't say it.
Sir Roger Penrose: I think the thing is I have been driven in directions.
I as just as you're pointing out in directions, which, uh, picking out the
particular rather than the general, right.
So, sure.
You have mathematics, which.
One of the huge aims in mathematics is being more and more general.
And you mentioned the and that's a beautiful example of that, where it's
simply generalizes over areas which you would never thought,
Eric Weinstein: but it also particular eyes.
So for example, yes.
It is only in low dimensions where you get to play the game with what are called
defamation complexes, where the first term is the symmetries and the problem.
The second term is the fields are the waves in the problem.
And the third term is the equations in the problem.
And then you get to cut it off at that point and have that be this magical
concept of an elliptic complex.
So, for example, in dimension four, um.
We gleaned something bizarre, which is that there are an infinite number of
different ways to do calculus in four dimensional space and only one way to do
it in every other dimension.
Sir Roger Penrose: Yes, yes.
Well, there's something special there about four.
Certainly.
That's true.
And the connections.
Maybe not that clear at the moment, but maybe we will see that this is
Eric Weinstein: maybe differentiable structures or part of part of physics.
Sir Roger Penrose: How
Eric Weinstein: amazing that, I'll give you another very bizarre one.
I don't know whether this has ever come up.
If you have two sets of symmetries known as Lee groups that act transitively.
On the same sphere in usual position.
Then either their intersection acts transitively on that sphere or the
dimension of that sphere is 15 and I believe that the intersection of the
groups looks like the electro strong group.
So it's very close to the political spectrum of theoretical physics pulled out
of nowhere, just from talking about, um, severe transitive group and yeah.
Sir Roger Penrose: Well, it's clear that one, I mean, in political physics, I mean,
I've never really been somebody who studied particle physics
Eric Weinstein: closely.
Is that right?
I didn't know.
Sir Roger Penrose: Well, I mean, in general I have met, but I suppose I felt
we may be a long way from really understanding what's going on there.
I dunno.
I mean, I hope, I hope that it was, well, you know, we have no, I said completely, I
often, I will have different views from these things.
Eric Weinstein: I think we're almost at the end.
Sir Roger Penrose: Well, that's an interesting thing.
Eric Weinstein: So how do you come to the idea that we may be quite far?
I'm
Sir Roger Penrose: not saying that we're necessarily far.
I think it's understanding why the groups are the groups that we see.
Um, and people have different theories about these.
Eric Weinstein: And let me ask you then a couple of questions go on.
Very early in this new stagnation post, the standard model.
People like, uh, Glashow and George, I and putty and Salaam put forward these
unifying symmetries that remain very odd, um, because they're so attractive and
powerful.
The prettiest of them being something called . Spin 10 which physicists persist
in calling?
So 10 for reasons that escape me.
Sir Roger Penrose: Yeah.
This is the one which doesn't exist or isn't that not that
Eric Weinstein: one?
Well, the original SU five which sits inside of spin 10 was disproven in its
most basic form.
And at that point, George, I and Glashow had been trained in the previous culture
of physics, which is that you fell on your sword.
When you predicted something and it wasn't true, and I think that they sort of rushed
to commit ritual suicide far too quickly.
Sir Roger Penrose: Yeah.
I just, maybe if I'd worked in the subject I form of clearer view.
It's just that from the outside, I'm not convinced that
I'm clearly there.
There are things which people have discovered, which are absolutely.
Fundamental and particle physics.
But somehow it hasn't got to the basic level, which I feel, I can see why these
groups of what they are and so on that let me not talk about it cause I'm not an
expert at that.
And not only giving you an impression.
And I, I suspect there will be, maybe not too long from now a better understanding.
I'm hoping that the theory might have something to say about it, but at the
moment, uh.
The area which needs to be explored here.
It hasn't been explored.
The things we did at one time, I'm sort of deviating a bit from the general trend,
but there was a question of how do we try, try it.
How we treat massive particles and twists of theory and naturally twist.
The theory describes massless things.
Uh, things go along the light cone and that sort of thing
Eric Weinstein: because you privileged the light cones.
Then the treatment of particles that were massless got a privileged tram and
privileges treatment.
Sir Roger Penrose: And not just that, you find transformations.
There is a way of representing the Maxwell equations.
This was the thing that I was mentioning about the TV program we have describing
the masculine equations, which you get out of this crucifix and it comes directly out
the, what about the direct equation?
You wanted to talk about massive particles.
Well, way it seems to lead you as you think of.
The, well, you see a massive particle has a momentum that, uh, which is timeline.
So it points within the cone.
And one way you could describe a timeline.
One is think of two.
No one's a two light light once you think it was zigzag.
So it's got a Zig and zag.
And that's when convenient way, Jake, where you might have one when she's made a
three zigzag Zog, something like that.
And you can get the timeline line out of.
Eric Weinstein: So you can build it up from there.
From primitive.
Sir Roger Penrose: That's right.
So the argument is that you have a twist of, for each of these zigs and zags.
And so you have, might have two of them, you might have three of them, and you see
how many of them give you the same.
And then you get these groups interested theory.
And these groups look like the Popsicle.
For the next group.
Say you've got S two, and as you three, and the idea we had is, Oh, well that's
the basis for these part of
Eric Weinstein: doesn't impress me much because it's ubiquitous, but as you three
is a , this is the group that represents the strong force that holds our, uh, yeah.
Sir Roger Penrose: Well, you see that as a thing that SU three gives you this.
Um.
Gay, you can gauge it.
So you have a, um, there is a difference between the STT and the SU three that the
quantum chroma dynamics, if you like, which is the theory which comes from
gauging se three is a genuine gauge theory.
But when you try and do it for, I see to the left for the electrons and, um,
Eric Weinstein: nutrient spin
Sir Roger Penrose: you, the gauging it doesn't really work because you've got a,
you've got a special.
It's not the full group, so on.
So there's something funny about it.
Okay.
And there are other theaters which might be a more promising way to go.
Let's not go into that cause this is all guessing.
But the idea is that you could develop a particle physics using many twists.
Eric Weinstein: In other words, if I'm not misunderstanding you, the idea is that the
extra data.
I mean we have a problem in the standard model in that we have effectively a an
origin story with two gods.
There's the God of Einstein that gives us space in time.
And then there's this other God that gives us SU three cross seq quests you one which
give us the non gravitational forces and all of these particle properties we call
quantum numbers.
And this has no connection
to the space and time data.
Sir Roger Penrose: Well, that's the sort of thing.
Yeah.
It looks as though it's quite separate.
I mean, they must be signed up at some stage, but we haven't got to that.
But the idea here was to try and do it via to assist.
Well, I'm just trying to say that we had, we had got very excited about this for
awhile, and then it was a long time ago because when people discover charm, I
think it was charming and suddenly this didn't fit.
And so we gave up, blah, blah, blah.
Eric Weinstein: And so by charm, you mean the quality of entirely.
Separate versions of the familiar family of matter.
So we now think we have three copies of matter where the second two are repeated
at higher mask, that sort of thing.
Sir Roger Penrose: Yes.
Yeah, that's right.
And so people would go, it didn't seem so simple at that point.
So, and the various things didn't seem to fit so well, but I think we should go back
to that from the insights that going from general relativity . I mean, there's a
long story which should be probably hard to describe here, but the uh,
construction,
she twisted theory, starts off as a theory about space, flat space time.
Eric Weinstein: That's what bothers me about it.
Sir Roger Penrose: Exactly.
And it's what bothered a lot of people.
And you see,
Eric Weinstein: I'm in good company then.
Sir Roger Penrose: I was at the time at the university of Texas for a year, and
this Alfred sheltered, put a lot of people together who were relative generativity
experts, hoping that something would come out of it, I guess.
And I had an office next to Ingleburn choking, whom I learnt a lot from, uh.
And on the other side, I had an office that was Roy Kerr's office and Ray Sachs
was a little way down.
And I have to backtrack because the question is where did, where did twist
theory come from?
Now.
I had lots and lots of ideas.
I was trying to fit together.
Part of it is we're trying to combine the Raymond sphere of relativity with the
Raymond sphere of quantum mechanics and various other mathematical ideas which
come into quantum field theory.
And they were sort of floating around, and I remember drawing a big piece of paper
with all of these ideas, which were roughly speaking of the nature that the
world we see.
It's described by real numbers, but sort of hiding behind it is a world of complex
numbers and they somehow control this world of real numbers.
So the dynamics is somehow controlled.
By the way, the complex numbers work, and this was a sort of vague thought I had,
and I couldn't think of a picture in which you added.
You see space time as four dimensions.
And I needed to add basically one more dimension because I wanted to incorporate
that idea.
Again, it's difficult to describe these things on a sort of popular program, but
it was an idea fundamental to quantum field theory.
Which has to do with splitting your field amplitudes into positive and negative
frequencies.
And it's angled birth and impressed upon me that this was very fundamental to
quantum field theory.
Most people weren't stressing it at that time.
And the way to think about this is to think of the reman sphere again, and you
have the equator of the Raymond sphere describing the real numbers together with
an infinity, and you've got this complex numbers.
On one side, one hemisphere, and also now have this sphere and the ones which are
positive for frequency, which is the fundamental thing for quantum pure theory
extend into one half.
So this to me was a very beautiful way of thinking about it, rather than splitting
everything into Fourier components and taking, taking half of them.
And that was, seemed to me
Eric Weinstein: four degrees of freedom with one extra real degree of freedom.
Sir Roger Penrose: One extra dimension, like the Raymond sphere, going from the to
the whole sphere.
And I wanted it to divide it into two halves.
And that was the picture I wanted.
And you tried to do the space.
Time it doesn't work was the first space time is four dimensional, and if you
complexify it, it's eight dimensional.
That doesn't divide in two.
Just something else.
So I, I knew that wasn't right.
Okay.
Now I was in Austin, Texas.
I had friends in Dallas.
Now this was the year in which Kennedy was assassinated.
And my friends in Dallas where to dinner and it was the next place that Kennedy was
to go to and he was going to give a speech and they all got worried because he didn't
turn up and they were January ish, quite right to be worried because he'd been
shot.
And this was a great shock to us all.
And so we as a society, we wanted to calm ourselves down.
And we went to the trip to trip from Austin.
Mary was in Dallas where the others were, and we went off in a few cars to San
Antonio and maybe to the coast.
And this was to try and recover from the shock and coming back.
Well, the women wanted to gossip and so on.
And I was, uh, with pitch to Ashford who isn't nice fellow.
I like him a lot.
And Gary in, but he didn't speak much.
So all their others wanted to gossip and they were sort of leftover.
And we, the two of us went in the car driving back to Austin.
And so I had a nice silent drive coming back and I started to think about these
constructions that I've a Robinson, he was in Dallas at the time, an English fellow
who lived in Dallas, and he constructed the solutions of the Maxwell equations,
which had this curious twist to them.
And I had understood these things and I realized that they were described by, as
you talked about the hop map or the Clifford parallels.
These are, you can think of a sphere in four dimensions, three-dimensional sphere,
four dimensions, and you have these circles which fill the whole space.
No two intersect and they every two link, beautiful configuration.
And I realized that this was the thing that.
Geometrically describe the solutions that I've ever had found, and I tried to think
about this and I thought, well, okay, these sort of describe,
well.
The way I've all had to thought about it.
Think of, think of a light Ray.
Yeah.
And then you think of all the light rays, which meet that light Ray.
So you've got the one light Ray and all the other sluts racers meet it, and that
family of light rays, you can have maximum solutions and maximum cause which point
along those rays.
So what he did, this was his trick.
You move that light right into the complex, so you add a complex number two,
the
Eric Weinstein: two extra dimensions.
Sir Roger Penrose: Well, it pushes the light rate as a complex, and then you can
construct this twisting.
You don't see the light rail anymore.
It's pushed into the complex, but you still got the complex family of light
rays, which meet it in a certain sense.
So I try to understand what that looks like.
And I thought, this is you're, you're pushing something into the complex and you
describe it by means of this complicated twisting family, right?
Race.
So I, in the drive back, I thought, well, let's count the number of dimensions.
There are these, as I call them later, Robinson congresses.
And I was.
Gratified or startled or whatever the right word is to find that the number, the
number of dimensions of these con, this family, right?
Where's was six, six dimensional family?
What's the dimension of the family of light rays?
Five.
So the ones you actually see directly at a light rays, that's the real thing.
And the thing which govern me in the mysterious complex world.
Add one dimension, they can twist right-handed.
That's one way lefthanded it's the other way, device thing into exactly what I was
looking for.
Eric Weinstein: Fantastic.
So I got that and then additionally had this structure of three complex
dimensions.
Sir Roger Penrose: Yes, yes.
When I, I went, I had to go back and get hold of my Blackboard and tried to wake it
up
Eric Weinstein: and I.
Great.
Sir Roger Penrose: So it was, it was a complex projective three space.
You have these two twisters and I, well, no, pretty chuffed with myself.
Didn't realize what this was.
You have a five dimensional space which divides this six.
Real.
In essence, basically it's is really a three complex dementia space into two
half.
Eric Weinstein: So if I'm understanding you, you would start out off with a seven
dimensional sphere.
You take an action by a circle to get see the complex project of three space, and
then you could further quotient that out by two spheres to get.
The four dimensional sphere,
Sir Roger Penrose: it's you have to have a, you can think of it as a sphere and,
um,
Eric Weinstein: maybe I'm not seeing it correct.
Sir Roger Penrose: You can't think of it as, as a sphere.
And, um,
Eric Weinstein: but you had a complex projected, yeah,
Sir Roger Penrose: you can think of a seventh sphere.
Eric Weinstein: Let me just tell you what I find fascinating about this story is
that you're talking about a.
Period, traveling between two cities where you realize something is the hop
vibration.
Sir Roger Penrose: Well, I knew it was the hot fire station, but I hadn't actually
thought of it.
Eric Weinstein: You may not know.
The following is adore singer took the work of Jim Simons and, um.
Uh, Frank Yang and on the trip to Oxford where you Michael,
Sir Roger Penrose: where
Eric Weinstein: he said, Oh my God, this is the quaternary ionic rather than the
complex hop vibration.
He said it was that
Sir Roger Penrose: when he
Eric Weinstein: realized that the self dual instant on equations were going to be
a revolution, and so it was the exact moment of the relationship to something is
non trivial.
In his case as the quote turning ionic rather than the complex hop vibration.
So this is almost an exact parallel between two stories because I've never
heard yours before.
Sir Roger Penrose: That's very interesting.
It also has relevant direct relevance.
Direct.
Yes.
Because as I think as we were just saying, cause you think of the vector space for
which the complex three spaces and of course that's for complex dimensions.
And then.
That means eight real,
Eric Weinstein: and this is, look, I want to tie this into a bigger thread, which I
think is fascinating.
I am not a devotee of string theory, nor am I of loop quantum gravity.
I think that most of what has been said about supersymmetry has been overbearing
and wrong.
I completely
Sir Roger Penrose: agree with all those things you're saying
Eric Weinstein: and.
I think that the intellectual carnage from these adventures in political, in
political economy or public relations or whatever you want to call it, are not
being born by the people who benefited from them, but by those who have to clean
up after.
Sir Roger Penrose: Something to me said,
Eric Weinstein: well, you don't have to say it.
I can say it because I'm not inside of the universities.
Now.
What I would claim is, is that while these people I think did a tremendous disservice
for all of us.
Taking what I consider to be our most accomplished intellectual community in the
history of academics, theoretical physics.
It is not the case that these people did nothing for 45 plus years, but what they
did do has never been told properly.
So I claimed to you at dinner the other night, like if you just look at the role
of curvature.
In our understanding of not only general relativity where it's been for over a
hundred years, but now in particle theory.
So we had a first revolution around the mid 1970s with what's called the Wu yang
dictionary, where a particular geometer who becomes the most successful hedge fund
manager in, in human history, meets arguably the most accomplished theoretical
physics physicist.
If it's not Weinberg, it might be yang in terms of what has been proven as
contributions.
They have an unbelievable.
Uh, interaction, which shows that the classical theory underneath particle
physics is as, or more geometric than the theory of Einstein using steam rods, fiber
bundles, and Eris months connections or vector potentials or what have you.
Then you have a second revolution.
Again involving, so that was the first one that his singer takes from Stony Brook to
Oxford.
Sir Roger Penrose: Do you have another
Eric Weinstein: one, which is the geometric quantization revolution with
your colleague Nick Woodhouse writing the Bible there?
Yes.
In which Heisenberg's uncertainty relations.
Strangely come out of curvature rather than there just being some sort of,
Sir Roger Penrose: Kevin, you're looking at connection in a Bumble.
Eric Weinstein: Well, there's this thing called the pre quantum line bundle where
line is against one of these planes.
So the terminology is all screwed up.
Nevertheless, the key point is, is that what we had previously treated as the
annoyance of the Heisenberg uncertainty principle became the beauty.
Of a geometric quantum.
So now you had the underlying classical theory is geometric.
The underlying quantum theory is now geometric.
And then again with your English group.
Uh, particularly Graham seagulls is a, is a real hero with Michael, the Tia, um,
pointing the pointing the way.
Sure.
You guys figure out that this weird grab bag that was called quantum field theory,
which is this thing above quantum mechanics that is needed for, if you're
going to have particles that change regimes in which the number of particles
changes.
Like something emits a photon unique quantum field theory.
You can't do it in quantum mechanics.
Yeah.
So that world was a grab bag that made absolutely no effing sense pedagogically
to anybody coming from outside of the discipline and what they taught us.
And this is coming from the, the 1980s on is the quantum field theory would have
been discovered by typology, wrists, and geometers.
Even if the physical world had never used it because it was actually a naturally
occurring augmentation of what's called boredom theory, which is an enhancement of
what you previously referred to as coal homology.
So these are three separate revolutions with people that almost nobody's ever
heard of.
Like Louis Alvarez Gulmay.
Um, you know, and, um, Dan Quillan, who I think is the world's greatest accidental
quantum field theorist.
For some reason the physics community is still telling us stories about
entanglement and about multi versus, and many worlds.
And this actual thing that happened, which is as gorgeous as anything I've ever seen,
has been a revolution that's been.
Plowing through mathematics and physics is covered up because they want to tell a
story about quantum gravity, which just doesn't hang together.
What the F
Sir Roger Penrose: yeah.
Well, I think,
Eric Weinstein: first of all, my wildly off,
Sir Roger Penrose: no, I don't think you are.
You see?
Yeah.
Um, I mean, a lot of these things I, I wish I knew more about, you see, for
example, Quillin theory and so on, which, which, uh, you know, life is too short,
but, but, uh, the,
Eric Weinstein: these askings out of the a T a singer theory where he, he finds these
determinant lines, which are coming out of non-local spectral information.
And building the basis maybe for pre quantum line bundles in which the
functions in that world become the waves that give us the theory.
Sir Roger Penrose: I think the trouble here, you see mathematics is full of all
sorts of beautiful deep theory and.
Most of mathematics as it exists now in a sense of what's written in journals and so
on, has almost no bearing on the physical world.
Now, you see, I feel totally convinced, and I think you're expressing something
similar, that if you find the right route through this stuff, you will.
Really find the key to what we're seeing in the physical world.
Now we've found many such keys and general relativity to the Lorencia and version of
Romanian
Eric Weinstein: semi Romani and her suit of Ramani
Sir Roger Penrose: suit and Romanian geometry.
So that's picked up a beautiful area of mathematics and turns it into, into, into
physics and X.
And then in reverse is, has, um.
Given a lot back to mathematics and also with quantum quantum theory clearly and
quantum field theory, but I think there are things that are hiding there, which
are very beautiful mathematics and which will reveal themselves as important in the
physics.
We haven't got to it yet.
What do
Eric Weinstein: you make of the fact that we now have three separate geometries.
So you have Ramani and geometry as the parent of general relativity.
Sir Roger Penrose: You
Eric Weinstein: have Eris money in geometry, which is based on sort of these
Penrose stairs coming from fiber bundle theory, which is the parent of the Maxwell
classical theory, but also the classical theory that would be underneath the strong
force holding protons together, which want to repel, and the weak force, which causes
beta decay.
Yeah.
All right.
And then you've got this other geometric theory, which is the geometric quantum,
and they're not the same geometry.
So for example, the geometry that that Jim Simons and a CN yang find has this
property called gauge symmetry.
You have the opportunity for gauge symmetry in the Einstein theory, but
because Einstein.
Takes curvature and uses something called linear algebra to project all of the
curvature information into a smaller subset, killing off something called vial
curvature.
If you gauge symmetry rise and then project, it's not the same as projecting
and then gauge symmetry rising.
So the opportunity to use gauge theory is lost by the specific genius of minds.
Sir Roger Penrose: Well, you see, there's a good example cause he did this amazing
thing when producing general relativity.
But then in his later years he tried to develop the theory and these unified field
theories, which from a mathematical point of view was not really a very.
Was not likely to give much new insights, but you know, he was right to think you
should find a unified scheme and so on and bring the, well, he troubled.
One trouble is he didn't really, he considered electromagnetism, but the
particle physics didn't play much of a role in what he was doing.
He
Eric Weinstein: died before corks were, he was innocent of SU three
Sir Roger Penrose: yes, sir.
I think the thing is there's huge beautiful things in mathematics and
we like to think, and I like to think that they do have a role in that.
Fundamental role roles that we've not yet discovered and operating, whether we, the
way the world works is dependent on very deep mathematics.
The trouble is that there's so many wrong steps in the sense that.
Many beautiful things in mathematics, which are guided in certain directions,
which from the point of view of mathematics are great.
And there can be generalizing ideas and, and um, revealing all sorts of previously
unknown beauties.
But the proportion of these, which we find has relevance to physics.
It's so it's very small at the moment now.
I think that in some ways, maybe the most powerful, the most, I'm sure, I mean
complex numbers and the analysis of complex numbers is one example where you
want, it does seem to see a role in operating the way the world works, and I'm
sure that we will find out other things.
It's just, there are so many temptations in directions, which are not particularly
to do with fear.
Eric Weinstein: But what I don't understand and what I'm absolutely
unsympathetic with, is that.
We have a lot of people who once upon a time had a lot of different ideas.
Now, most of the ideas at the moment, if we're brutally honest, it, we are so
constrained by this point in our story in theoretical physics that almost every new
idea is dead on arrival unless you specifically keep it from predicting
things that we don't see.
Yo.
Yeah.
Right.
And so what I see is, is that you've got different, and this is a sociological and
economic critique, is that you have.
A class of naughty boys who are very badly behaved, who get to make all sorts of, um,
claims, talk to the press incessantly over decades about all the wonderful things
they're going to do, which they don't do.
And then you haven't got another group of people whose feet are held to the fire,
where the instant they start to consider something that might, for example, violate
a no-go theorem.
Uh, they're roundly humiliated.
Now, what I see you as having done is to carve out a very unusual niche.
Twister theory is, at a minimum, an incredibly valuable tool for that.
Generating solutions on one space from solutions on another, let's say.
However, it's also somewhat tolerated within the system.
It's a minority point of view.
It's a minority community.
But it is allowed to play a parallel game to the string world where the string
theorists have lived for years, in my estimation, on externalities.
There are lots of positive externalities of having, and I do think that's the
smartest community out there.
I do think that in general, they're smarter than the relativists.
They're even smarter than most of the geometers.
They're in sufferable.
Oh,
Sir Roger Penrose: they're very clever people.
Eric Weinstein: Very clever basal, very insufferable.
And the problem with that community is, is that it's actually accomplished a great
deal that isn't of a stringy nature.
Sir Roger Penrose: That's true.
That's true.
Eric Weinstein: And I do think that what they've done is they've, instead of
quantizing geometry, which is what quantum gravity was supposed to be, they, it
backfired.
And they, they had the geometry.
Um, geometry is the quantum, and that's the main legacy of these people is it's
an, the, the, the, uh, . No, they, they took off for, uh, for Paris and landed in
Tokyo, which is very impressive as a feat, but it wasn't what they were setting out
to do.
Sir Roger Penrose: No, I think basically I agree with that and certainly string
theory has had a big influence in various areas of mathematics, but the influence
directly in physics has been pretty minimal.
I think.
Eric Weinstein: What do you think about the legacy of something like
supersymmetry, which is,
Sir Roger Penrose: that's an interesting question,
Eric Weinstein: isn't it?
Sir Roger Penrose: Yes.
Well, it's very interesting, partly from a personal point of view, because when I
first heard about it, and a lot of it was on conformal supersymmetry, right.
And I could see there was a lot of connection with Twista theory.
The only thing I didn't like was you were led to these algebras, which didn't
commute and uh, well, there was the square or something was zero or something,
whatever.
I mean, they weren't the kind of algebra that you needed.
Interests a theory.
You need a complex analysis.
But anyway, I, I went, I visited Zunino.
At one point, and I was in verse intrigued, cause I could,
Eric Weinstein: this is half of the duo that came up with the sort of original
lead.
Original deep,
Sir Roger Penrose: yes.
A
Eric Weinstein: supersymmetric model.
Absolutely.
Sir Roger Penrose: Yes.
And so I thought there's enough connections here.
I'd like to understand it better.
And yeah, I think I answered it a bit more.
But one thing I remember particularly, this is a little bit of a side point, but
I was talking to them about two components, spinners, and I realized he
was somebody who understands it, understood it perfectly well, and he told
me this story.
He said he once written a paper in which he used two component spinners and it was
worked out very well.
A few months later, Abdusalam did the same thing, but using four components mirrors
and he said, everybody referred to ABIs allows paper and nobody referred to his
paper and he said, well, that from then on he said he vowed never to write a paper
using the two spinning formalism, which I thought was pretty ironic, particularly
since Dirac himself intriguing that a lot of people in the early days of looking at.
Generalizing the Dirac equation for high spins and so on.
And there were, you know, Duffin Cameron, and we're the only ones from, I forget
what, they were all called, different names for all the different spins and they
were all in course and spoke.
I remember and direct wrote this, had written this I think earlier, I can't
remember the history of which is which.
But I think earlier this paper where he did a whole lot using two spinners.
I'm direct using two spinners where you see clearly he knew about them.
So I was, I was concerned because he had acted on them.
But this was much earlier than that.
He had this paper in the Royal society describing all the different spins with
two spinners, much more clear, a much more general, simple, systematic.
And again, nobody seemed to refer to directs paper, which is quite curious
because he'd.
I mean, there's a huge irony there because he wrote his initial paper using these
four spinners and he didn't realize until maybe pointed it out by Vanderbilt,
London, have no idea where he got it from.
You realized that you could write all this in two spinners, and in some ways it was
simpler and use this to generalize to all the spins, but for some.
Curious reason, nobody or very few people seem to refer to directs paper.
Eric Weinstein: Well, you know about this famous a situation where Fineman found
effectively the path integral formalism in some paper that had published in the
Soviet union.
Sir Roger Penrose: That's right.
Eric Weinstein: And then fireman, you know, was trembling.
I think in the end as director, you realize when you said that these two
things were analogous, that they're in fact proportional and direct said, are
they,
Sir Roger Penrose: you had to be careful with your right, cause I had a
When I'd first written things in two spinners and I'd written general
relativity with two spinners, and I'd found certain things came out very
beautifully.
And this thing that everybody was worrying about, calling them at that time called
the bell Robinson tensor, right?
And you could, it's dropped out of use to spinous and the principal Nell directions
and all sorts of things.
And the thing is, you have this equation, which is the Banky identities written in
two spinners.
And you can see it's just.
The same equation that you write for masters fields, Maxwell's equations.
It's the same you Trina, if it had no mass, just to say that just the same, you
have it in a more into the more, the higher the spin, the more indices, but
it's the same equation and you can see it's conformity in variant or justice.
Eric Weinstein: Part of the problem that you're going to get into with all of these
things is I would venture to argue that even the lowly Bianca identity, which is
at the heart of how Einstein figured out how to do his equations.
Yes.
To make sure that, um, effectively his vectors pointed perpendicular to the
orbits of the symmetries that he was considering that we don't really even
understand the things that are given to us for free fully.
There's an old paper of Jerry Kasdan, I believe in which he actually reduces the
Bianca identity from much more fundamental principles.
And the same thing is true with the sudden appearance of a version of the calculus
due to, um, levy Chivita from merely choosing, um, rulers and protractors.
Sir Roger Penrose: I really.
Eric Weinstein: Worry that we never actually grounded these fields properly.
I don't know if you're familiar.
I think it's checkoff who said that if a, if a gun is placed above the mantle place,
uh, in the first act, it must be fired by seeing for, well, for example, we have
this thing called the torsion tensor.
Oh God.
That everybody's introduced to in the first day of Ramani in geometry, and then
they.
Properly or encouraged to forget about thereafter.
Never really seems to show up in any meaningful way, anywhere
Sir Roger Penrose: mean.
It's always a puzzle.
I know, and I've never quite made up my mind about it.
Let's not go into that story.
That, yes, I don't use it.
All right.
I once wrote a paper,
Eric Weinstein: but to ask you, just in terms of the path forward, um, it strikes
me that what we have learned.
About our physical world and what comes up in this book is a very frightening nature
that Einstein's equations, when you really understand them through Hilbert's insight,
come from the simplest possible thing we could minimize.
Sir Roger Penrose: Oh,
Eric Weinstein: yes.
Same thing for Maxwell's equations.
They spread from the electromagnetism to the weak force into the strong force
because it was the simplest possible thing that could be optimized.
The Lagrangian.
I'm trying to avoid saying those words and then
Sir Roger Penrose: there's no,
Eric Weinstein: and then derog.
Sir Roger Penrose: Yes.
Eric Weinstein: Third equation to complete this triptych is.
The equation for matter, which generates all of something called theory, which is
absolutely fundamental.
So I could make an excellent argument that the three major equations to be
supplemented by one for the Higgs field, now that we found it, um.
Are the simplest and best possible equations of their type.
Not that we've found so far, but provably.
So
Sir Roger Penrose: yes, I think the trouble with simplicity arguments, which I
agree with, is that it's simple in one context and much simpler context.
It may be,
Eric Weinstein: but nature has shown such.
I mean, the thing that I can't get over is that her taste in mathematics.
You know, I, I've analogize this to rating a jewelry store with millions of pieces
and in under half a minute finding all the best stuff
Sir Roger Penrose: I wanted to finish a story that you see we touch didn't quite
finish.
It relates to something you were saying earlier, which I, at one point.
You see, Dereck was at the same college as I was st John's college and Cambridge
where I was a fellow.
And I happened to be sitting opposite him at one point.
And I had been working on these two spinner ways of looking at general
relativity.
And so I said to him, I thought, you know, I thought something he might be interested
in, could I, would he have opportunities to talk me about it?
So.
So he reserved a room and I had a little discussion with him and then I wrote down
this equation, which was this wave equation which you, which represents the
Bianca identities.
And I wrote this thing down and direct.
I thought he would instantly recognize it cause it's basically the same equation
that he had in his paper with all these different spins.
And he asked me if I wrote down the question, he said, where does that
equation come from?
So I said, it comes from the Bianche identities.
And he said, what does it be?
Yankee identities.
Eric Weinstein: Holy cow.
Sir Roger Penrose: And I thought, well, he's been writing all these papers and
general relativity.
He must know perfectly well.
You simply rediscovered them himself.
He just didn't know.
They were called the Bianca identities.
I don't know.
It's a very curious story,
Eric Weinstein: and this was in the form that the derivative of the curvature in
terms of the natural derivative is equal to zero.
That's,
Sir Roger Penrose: yeah.
In vacuum, say yes.
And you take the, the vial curvature, which is all ms left as everyman
curvature, and you write that in spinners and it's a spinner with four indices
completely symmetrical.
And then when you write the derivative, it's the derivative acting on those four
things.
In one contraction, the deriv has got two indices and you can track one of those,
and that's their equation.
That's banishes.
That's the equation.
Same as the Maxwell equation, the same as nutrient.
Now, if you had one index and no mass, and it's the way I think about these things
and the conformal invariance is very crucial.
That leaves me to all sorts of ideas that I wouldn't have thought of otherwise.
And it was clearly the sort of thing direct with it played with himself because
his equation, all the highest spin equations, although an excuse, actually in
his paper, he did the massless case a different way, which I never quite
understood why.
But anyway, so is there clearly things that he understood completely and somehow
maybe never connected?
I don't know what it was.
Do you,
Eric Weinstein: did you read his 1963 article in scientific American where he
makes a very interesting case against, um, naive application of the scientific
method?
Sir Roger Penrose: No, I don't.
That's the Iraq sent in Saturday.
Eric Weinstein: Absolutely.
And his point should have seen
Sir Roger Penrose: that.
Eric Weinstein: Um, yeah, he makes the point in the case of Schrodinger and he
says, Schrodinger would not have been led into error if he had not been pressed for
agreement with experiment because Schrodinger then.
Uh, after publishing, there was a period of time where it wasn't understood that
spins somehow entered the picture and complicated the theoretical prediction
with its experimental verification.
But I think secretly he was actually talking about himself where he had
introduced the equation.
There had to be positively and negatively charged.
Particles.
And at that time the electron and the proton were known, but the positron and
the anti-proton were not.
And so he linked those two.
And Heisenberg immediately dinged him and said, wouldn't those be of the same mass?
And you're obviously making an error.
And he didn't stick to his guns or have the courage of his convictions to predict
the new particles.
And I think that that 1963 paper from scientific American is direct trying to
give us a gift from Mount Olympus to say.
Stop with the incessant insistent on the naive scientific method.
Give yourself more room to imagine more room to play, more room to be wrong.
Sir Roger Penrose: I think that's crucial thing.
He said he, that was the thing about direct.
He just didn't want to be wrong.
Now he was very worried about saying things that were wrong.
And so often he would say nothing rather than anything.
So this is a big thing with him, and I think he was disturbed by, yeah, you're
right.
I mean, he could have predicted instantly,
Eric Weinstein: I think he needed more freedom and he didn't have it and he tried
to give that
Sir Roger Penrose: fade away.
Being too timid.
Yes.
Actually what I'm crushing.
Yeah.
Eric Weinstein: Let me ask you a harder question,
Sir Roger Penrose: right?
Eric Weinstein: Um, because we haven't asked you any hard questions to begin
with.
Sir Roger Penrose: Um,
Eric Weinstein: your going to be in your 90s soon
Sir Roger Penrose: if you were to come working.
Yes.
Eric Weinstein: If you were to point.
To younger people.
There seems to be a failure to pass torches that I've noticed.
And you don't seem to be the sort of a person I would imagine to have that
problem.
Who would you be pointing to?
Sir Roger Penrose: A human
Eric Weinstein: being.
Individuals.
Sir Roger Penrose: Ooh, that's a tricky one.
I don't, I,
Eric Weinstein: you don't have to poach.
Push anyone down, but who would you, who would you build up an.
Who's young and vital, who might be, you might say, look, if anyone's got the
scent, this might be a person to look at.
Sir Roger Penrose: I think I'm not going to take you up on that one.
I'll decline.
Eric Weinstein: I'll decline to push further.
Sir Roger Penrose: Yes.
It's just as a, it's not so obvious.
I mean, I've certainly had people clearly good and inspirational ways and think of
things I'd never thought of.
But it's a bit hard.
It's, I don't know enough people.
I think it's probably somebody I don't know.
Let me see.
Yes.
Eric Weinstein: Do you, um, do you worry that the glory that is the Oxford, um,
school of geometry and physics may not continue.
Without.
Sir Roger Penrose: Do worry a bit about that.
Yes.
I mean, there wasn't,
Eric Weinstein: it's an unbelievable nucleus of people.
Sir Roger Penrose: Yeah, absolutely.
Right.
Very rockabilly,
Eric Weinstein: and I worry that the UK doesn't value itself enough.
I think that you guys are so idiosyncratic and so weird and badly behave.
I don't know what to call it, but the UK is punched way above its weight by
tolerance, tolerating and encouraging personalities, idiosyncrasies.
Sir Roger Penrose: That.
I think that there, there is a point there.
I, I, I wouldn't know how to generalize across countries cause maybe, uh, but I
think, I think you're right to some degree there is tolerance of Accenture city
which, which is specifically a kind of intense kind of tolerance, which is
specifically English or British, I should say, British.
I don't know.
I, I'm nervous about saying things like that cause you find somebody who Springs
up somewhere else
Eric Weinstein: or somebody else, somebody will hate you for it.
But quite honestly, what are they going to do?
Make you pay with your career?
I don't think it's going to happen.
Sir Roger Penrose: Yeah.
But I think,
I think when you say about the geometry developed in Oxford is pretty distinctive.
Yes.
Um, but then the people moved out too.
I mean, Michael went back to Cambridge.
Eric Weinstein: Well, that's, well, but the Oxford system, I mean, if, if I, I
don't, I don't have to make it so peculiar to Oxford, but you know, even if I think
about like a Nigel Hitchen.
Um, or a Mason, I guess, has been in that system.
Sir Roger Penrose: Yes.
Not that I grew up with very Eggo.
Pyx clearly.
Yeah.
They're very
Eric Weinstein: jealous.
Sir Roger Penrose: No doubt about that.
Yes.
Yeah.
But it's, I mean, you're asking me to how big a thing then
Eric Weinstein: let me just, yeah.
One final thing.
Have you been to the, um, courtyard.
Of the Simon center for geometry and physics at Stony Brook, which is tiled
with Penrose tiles.
Sir Roger Penrose: I have not been there.
I've seen photographs at the tiling.
Yes,
Eric Weinstein: man.
Recommend a pilgrimage.
They have a wall there as well.
Sir Roger Penrose: Yes.
Eric Weinstein: And they so called iconic wall, which because Jim Simon's made so
much money, he was able to chisel.
Um, some of them world's most important equations and principles that you and I
probably think of as being the hallmarks of
Of being alive, uh, you know, just contact with these things.
They're actually in a place that can be visited with a key.
And I always think about in a fan, fantastic world, unlocking that wall and
seeing whether it's in fact a gateway to something else.
Sir Roger Penrose: Yeah, it was a long time since I've been there and I haven't
been there since the wall of the pavings
Eric Weinstein: I recommended, let me ask you one final question to pose out.
Um, we all worry.
When we've gotten this far along, uh, your road to reality, if you will, that we're
not going to live to see the final chapter or completion, that this is a mystery,
like none other.
That probably in some sense does have an explanation in it and it kind of end.
Is that something that.
That occupies you.
I mean, I find you absolutely vital and, and um, sharp as a tech, but like I, I'm
worried about this at age 54.
That what if, what if I don't get a chance to see the end?
Is that something that animates?
Sir Roger Penrose: So there's a huge amount of chance involved in these things.
So it's a gamble, I think, you know, to see a real end til this eye is too remote
for that.
But on the other hand.
Easy.
We didn't really discuss where twisted theory is stuck or has stuck for 40 years
and where I think it's got somewhat unstuck.
Eric Weinstein: You think it will be the answer?
Sir Roger Penrose: Well, I'm not sure how frightened.
Take us.
He said, that's not the question, but the main problem, as I saw it in twist a
theory, it's a sort of rather surprisingly things which worked surprisingly well, and
one of these is to construct solutions of the unsigned equations or the Richie flat
four dimensional space times, which were completely generic.
Provided they were anti self deal.
Now what that means is you've got a complex solution of ad science vacuum
equations, which are lefthanded in some sense, and then why do we want complex
solutions anyway?
You know, you want the real solutions.
When you say, I thought at one point, well, one useful where thinking about the
complex ones as these are wave functions.
Cause my functions are naturally complex.
So I thought, well this is a wave function, but it's a nonlinear wave
function.
So I called it the non linear Gravatar and it seemed to be a big step forward and
understanding how quantum mechanics and gravity fits in together.
But it got stuck.
It got stuck with what I call the googly problem.
Now you have to, if you're not a member of the former British empire, you probably
don't want to know what a googly is.
It's a, it's a ball bowled in the game of cricket.
You see in cricket, unlike baseball, you'd like to spin the ball about its axis, the
direction it spins about the direction, which it's moving, cause it bounces.
And that's a key thing.
So it bounces one way or the other.
And to make it spin lefthanded.
Is has a certain action with your hand.
And there's a clever thing that people do who are really good at this, who can looks
as though they're using the same action, but it's very cleverly done that the ball
spins the other way, and you throw occasional one of these in and it gets the
batsman completely bamboozled.
And that's called a Googley.
So using the same action, the spins, the ball lefthanded, you spin it right-handed.
So I use that term because he's very an apt.
You have the frame, the truest of framework, which naturally gives you the
left-handed gravity.
Tom, make it do the right handed one.
And I struggled and struggled and struggled and have all sorts of wild ideas
for how to do this.
And I came up with one, which I was very proud of, but it needed a cosmological
constant to be zero.
And so I thought there is no cosmological constant.
And then I had a discussion with Jerry Ostreicher, who was a very distinguished,
uh, astrophysicist, and I was talking about the observations that there seem to
be a
Exponential expansion of the universe, which, uh, seemed to indicate the presence
of a positive, cosmological constant.
So I said, well, you know, surely that's not really there.
It's dust or something.
And he looked at me, he said, that's not the point.
There are so many things in cosmology.
Which works so much better if you put this cosmological constant in.
So I had to retract my view.
I threw out my construction, but it took me many years to see when you have a
cosmological constant, you could do something that didn't work without it, and
this enables you to have it.
Construction, which I think solves this googly problem.
The trouble is, from my point of view, it translates into algebra rather than
geometry.
Oh, there you can get back to geometry by thinking of as a connection on the bundle.
So that is a geometrical thing.
It is a good thing, connection.
And then you talk about this algebra, and then instead of patching spaces together
to make a curve manifold, you patch the algebras together.
Then they have to be non-competitive.
Point that made clear to me by Michael a T at one point, and this is the proposal and
you just construct these algebras and they are connections on bundles and this
enables you, at least in principle, to find a generic solution of the vacuum
equations with cosmological cancer.
When I say find it's,
Eric Weinstein: you mean what would be called an Einstein manifold?
The Ricci scaler none.
Zero.
Sir Roger Penrose: Constantly nonzero.
That's right.
Exactly what people call an Einstein space.
But this is Lorencia and they're not positive.
Definitely.
But it's not a construction event that you sort of write in this for me, Don, is you
construct this algebra and then you've looked for sub algebras and the algebra,
and that's not the thing I'm good at doing, but still it needs to
Eric Weinstein: be worked out.
Sir Roger Penrose: Oh, absolutely.
And I got distracted by cosmology and other things, and stay away
Eric Weinstein: from that consciousness stuff.
It'll suck all your time.
Sir Roger Penrose: Well, that is a problem actually.
Yeah.
But you see other people are doing that.
I'm not really doing that.
They get me to give lectures on it and I give the same election, which I can many,
many
Eric Weinstein: was.
I have to say that if, uh, if you stick with what you've, what you've done in
physics, um, and keep trying to push that ball forward, I can't imagine a better use
of your time.
Um, you are invited anytime you want to come back and return to this program.
This has been an extremely heavy load for our listeners.
No, don't apologize.
Don't apologize for that.
We have to start doing something different because people are hungry to know.
What does it actually sound like to hear people talking about where things are
rather than some spoonfed prettified version that's like pre chewed as if it
were baby food.
I don't think they want that anymore.
Sir Roger Penrose: No, I agree.
I agree.
And I think even if you don't understand all the things that they get, some feeling
for some of the things people are trying to do is, is really important.
We as important as the details or perhaps more
Eric Weinstein: part of it is just respecting our listeners.
They know that we don't know how to get this to them in exactly the right way.
And so I think we have the best listenership of any program out there
because they've been habituated to recognize that not every program, and not
every sentence is going to make sense.
So Roger, um, thank you for coming through.
What?
Come back anytime and we'd love to continue the conversation about twisters
or anything else you'd like
Sir Roger Penrose: to talk about.
I've really enjoyed it.
Thank you very much.
Yes.
Eric Weinstein: All right.
You've been through the portal with sir Roger Penrose.
Hope you've enjoyed it.
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Sir Roger Penrose: will.