Lex Fridman Podcast - #187 - Frank Wilczek: Physics of Quarks, Dark Matter, Complexity, Life & Aliens

The following is a conversation with Frank Wilczek,

a theoretical physicist at MIT who won the Nobel Prize

for the co discovery of asymptotic freedom

in the theory of strong interaction.

Quick mention of our sponsors,

the Information, NetSuite, ExpressVPN, Blinkist,

and Aidsleep.

Check them out in the description to support this podcast.

As a side note, let me say a word about asymptotic freedom.

Protons and neutrons make up the nucleus of an atom.

Strong interaction is responsible

for the strong nuclear force that binds them.

But strong interaction also holds together the quarks

that make up the protons and neutrons.

Frank Wilczek, David Gross, and David Politzer

came up with a theory postulating

that when quarks come really close to one another,

the attraction abates and they behave like free particles.

This is called asymptotic freedom.

This happens at very, very high energies,

which is also where all the fun is.

This is the Lex Friedman Podcast,

and here is my conversation with Frank Wilczek.

What is the most beautiful idea in physics?

The most beautiful idea in physics

is that we can get a compact description of the world

that’s very precise and very full

at the level of the operating system of the world.

That’s an extraordinary gift.

And we get worried when we find discrepancies

between our description of the world

and what’s actually observed

at the level even of a part in a billion.

You actually have this quote from Einstein

that the most incomprehensible thing

about the universe is that it is comprehensible,

something like that.

Yes, so that’s the most beautiful surprise

that I think that really was to me the most profound result

of the scientific revolution of the 17th century

with the shining example of Newtonian physics

that you could aspire to completeness, precision,

and a concise description of the world,

of the operating system.

And it’s gotten better and better over the years

and that’s the continuing miracle.

Now, there are a lot of beautiful sub miracles too.

The form of the equations is governed

by high degrees of symmetry

and they have a very surprising kind

of mind expanding structure,

especially in quantum mechanics.

But if I had to say the single most beautiful revelation

is that, in fact, the world is comprehensible.

Would you say that’s a fact or a hope?

It’s a fact.

We can do, you can point to things like

the rise of gross national products per capita

around the world as a result of the scientific revolution.

You can see it all around you.

And recent developments with exponential production

of wealth, control of nature at a very profound level

where we do things like sense tiny, tiny, tiny, tiny

vibrations to tell that there are black holes

colliding far away or we test laws as I alluded to

whether it’s part in a billion and do things

in what appear on the surface

to be entirely different conceptual universes.

I mean, on the one hand, pencil and paper

are nowadays computers that calculate abstractions

and on the other hand, magnets and accelerators

and detectors that look at the behavior

of fundamental particles and these different universes

have to agree or else we get very upset

and that’s an amazing thing if you think about it.

And it’s telling us that we do understand a lot

about nature at a very profound level

and there are still things we don’t understand of course

but as we get better and better answers

and better and better ability to address difficult questions

we can ask more and more ambitious questions.

Well, I guess the hope part of that is because

we are surrounded by mystery.

So one way to say it, if you look at the growth GDP

over time that we figured out quite a lot

and we’re able to improve the quality of life

because of that and we’ve figured out some fundamental things

about this universe but we still don’t know

how much mystery there is and it’s also possible

that there’s some things that are in fact incomprehensible

to both our minds and the tools of science.

Like the sad thing is we may not know it

because in fact they are incomprehensible

and that’s the open question is how much

of the universe is comprehensible?

If we figured out everything what’s inside the black hole

and everything that happened at the moment of the Big Bang

does that still give us the key

to understanding the human mind

and the emergence of all the beautiful complexity

we see around us?

That’s not like when I see these objects

like I don’t know if you’ve seen them like cellular automata

all these kinds of objects where the from simple rules

emerges complexity, it makes you wonder maybe

it’s not reducible to simple beautiful equations

the whole thing only parts of it.

That’s the tension I was getting at with the hope.

Well, when we say the universe is comprehensible

we have to kind of draw careful distinctions

about or definitions about what we mean by that.

Both the universe and the kind of and the comprehensive.

Exactly, right so the so in certain areas

of understanding reality we’ve made extraordinary progress

I would say in understanding fundamental physical processes

and getting very precise equations that really work

and allow us to do the profound sculpting of matter

to make computers and iPhones and everything else

and they really work and they’re extraordinary productions

on the other but and that’s all based

on the laws of quantum mechanics

and they really work and they give us tremendous control

of nature on the other hand as we get better answers

we can also ask more ambitious questions

and there are certainly things that have been observed

even in what would be usually called the realm of physics

that aren’t understood for instance there seems to be

another source of mass in the universe

the so called dark matter that we don’t know what it is

and it’s a very interesting question what it is then

but also as you were alluding to there’s it’s one thing

to know the basic equations it’s another thing

to be able to solve them in important cases

so we run up against the limits of that

in things like chemistry where we’d like to be able

to design molecules and predict their behavior

from the equations we think the equations could do that

in principle but in practice it’s very challenging

to solve them in all but very simple cases

and then there’s the other thing which is that a lot

of what we’re interested in is historically conditioned

it’s not a matter of the fundamental equations

but about what has evolved or come out

of the early universe and formed into people and frogs

and societies and things and the laws of physics

the basic laws of physics only take you so far

in that it kind of provides a foundation

but doesn’t really that you need entirely different concepts

to deal with those kind of systems

and one thing I can say about that is that the laws

themselves point out their limitations

that they kind of their laws for dynamical evolution

so they tell you what happens if you have

a certain starting point but they don’t tell you

what the starting point should be at least yeah

and the other thing that emerges

from the equations themselves is the phenomena

of chaos and sensitivity to initial conditions

which tells us that you have that there are intrinsic

limitations on how well we can spell out the consequences

of the laws if we try to apply them.

It’s the old apple pie if you want to what is it

make an apple pie from scratch you have to build

the universe or something like that.

Well you’re much better off starting with apples

than starting with quarks let’s put it that way.

In your book A Beautiful Question you ask

does the world embody beautiful ideas?

So the book is centered around this very interesting

question it’s like Shakespeare you can like dig in

and read into all the different interpretations

of this question but at the high level what to use

the connection between beauty of the world

and physics of the world.

In a sense we now have a lot of insight into what

the laws are the form they take that allow us

to understand matter in great depth and control it

as we’ve discussed and it’s an extraordinary thing

how mathematically ideal those equations turn out to be.

In the early days of Greek philosophy Plato had this model

of atoms built out of the five perfectly symmetrical

platonic solids so there was somehow the idea

that mathematical symmetry should govern the world

and we’ve out Platoed Plato by far in modern physics

because we have symmetries that are much more extensive

much more powerful that turn out to be the ingredients

out of which we construct our theory of the world

and it works and so that’s certainly beautiful.

So the idea of symmetry which is a driving inspiration

in much of human art especially decorative art

like the Alhambra or wallpaper designs or things

you see around you everywhere also turns out to be

the dominant theme in modern fundamental physics

symmetry and its manifestations the laws turn out

to be very to have these tremendous amounts of symmetry

you can change the symbols and move them around

in different ways and they still have the same consequences.

So that’s beautiful that these concepts that humans

find appealing also turn out to be the concepts

that govern how the world actually works.

I don’t think that’s an accident.

I think humans were evolved to be able to interact

with the world in ways that are advantageous

and to learn from it and so we are naturally evolved

or designed to enjoy beauty and it’s a symmetry

and the world has it and that’s why we resonate with it.

Well it’s interesting that the ideas of symmetry

emerge at many levels of the hierarchy of the universe.

So you’re talking about particles but it also is

at the level of chemistry and biology

and the fact that our cognitive sort of our perception

system and whatever our cognition is also finds

it appealing or somehow our sense of what is beautiful

is grounded in this idea of symmetry

or the breaking of symmetry.

Symmetry is at the core of our conception of beauty

whether it’s the breaking or the non breaking

of the symmetry.

It makes you wonder why.


So I come from Russia and the question of Dostoevsky

he has said that beauty will save the world.

Maybe as a physicist you can tell me

what do you think he meant by that?

I don’t know if it saves the world

but it does turn out to be a tremendous source

of insight into the world.

When we investigate kind of the most fundamental

interactions, things that are hard to access

because they occur at very short distances

between very special kinds of particles

whose properties are only revealed at high energies.

We don’t have much to go on from everyday life

but so we have when we guess what the,

and the experiments are difficult to do

so you can’t really follow a very wholly empirical procedure

to sort of in the Baconian style figure out the laws

kind of step by step just by accumulating a lot of data

what we actually do is guess.

And the guesses are kind of aesthetic really.

What would be a nice description

that’s consistent with what we know

and then you try it out and see if it works

and by gosh it does in many profound cases.

So there’s that but there’s another source of symmetry

which I didn’t talk so much about in a beautiful question

but does relate to your comments

and I think very much relates to the source of symmetry

that we find in biology and in our heads, you know,

in our brain which is that, well it is discussed a bit

in a beautiful question and also in fundamentals

is that when you have, symmetry is also a very important

means of construction.

So when you have for instance simple viruses

that need to construct their coat, their protein coat,

the coats often take the form of platonic solids

and the reason is that the viruses are really dumb

and they only know how to do one thing

so they make a pentagon then they make another pentagon

and they make another pentagon

and they all glue together in the same way

and that makes a very symmetrical object sort of.

So the rules of development when you have simple rules

and they work again and again, you get symmetrical patterns.

That’s kind of, in fact it’s a recipe also

for generating fractals, like the kind of broccoli

that has all this internal structure

and I wish I had a picture to show

but maybe people remember it from the supermarket

and you say how did a vegetable get so intelligent

to make such a beautiful object

with all this fractal structure

and the secret is stupidity.

You just do the same thing over and over again

and in our brains also, you know, we came out,

we start from single cells and they reproduce

and each one does basically roughly the same thing.

The program evolves in time, of course,

different modules get turned on and off,

different regions of the genetic code

get turned on and off but basically,

a lot of the same things are going on

and they’re simple things

and so you produce the same patterns over and over again

and that’s a recipe for producing symmetry

because you’re getting the same thing in many, many places

and if you look at, for instance,

the beautiful drawings of Roman Icahal,

the great neuroanatomist who drew the structure

of different organs like the hippocampus,

you see it’s very regular and very intricate

and it’s symmetry in that sense

because it’s many repeated units

that you can take from one place to the other

and see that they look more or less the same.

But what you’re describing, this kind of beauty

that we’re talking about now is a very small sample

in terms of space time in a very big world

in a very short, brief moment in this long history.

In your book, Fundamentals, 10 Keys to Reality,

I’d really recommend people read it.

You say that space and time are pretty big or very big.

How big are we talking about?

Can you tell a brief history of space and time?

It’s easy to tell a brief history, but the details get very

involved, of course, but one thing I’d like to say

is that if you take a broad enough view,

the history of the universe is simpler

than the history of Sweden, say,

because your standards are lower.

But just to make it quantitative,

I’ll just give a few highlights.

And it’s a little bit easier to talk about time,

so let’s start with that.

The Big Bang occurred, we think.

The universe was much hotter and denser and more uniform

about 13.8 billion years ago,

and that’s what we call the Big Bang.

And it’s been expanding and cooling,

the matter in it has been expanding and cooling ever since.

So in a real sense, the universe is 13.8 billion years old.

That’s a big number, kind of hard to think about.

A nice way to think about it, though,

is to map it onto one year.

So let’s say the universe just linearly mapped

the time intervals from 13.8 billion years onto one year.

So the Big Bang then is on January 1st at 12 a.m.

And you wait for quite a long time

before the dinosaurs emerge.

The dinosaurs emerge on Christmas, it turns out.


12 months, almost 12 months later.

Getting close to the end, yes.

Getting close to the end.

And the extinction event that let the mammals

and ultimately humans inherit the Earth

from the dinosaurs occurred on December 30th.

And all of human history is a small part of the last day.

And so, yes, so we’re occupying only,

and a human lifetime is a very, very infinitesimal part

of this interval of these gigantic cosmic reaches of time.

And in space, we can tell a very similar story.

In fact, it’s convenient to think that the size

of the universe is the distance that light can travel

in 13.8 billion years.

So it’s 13.8 billion light years.

That’s how far you can see out.

That’s how far signals can reach us.

And that is a big distance.

That is a big distance because compared to that, the Earth

is a fraction of a light second.

So again, it’s really, really big.

And so if we wanna think about the universe

as a whole in space and time,

we really need a different kind of imagination.

It’s not something you can grasp

in terms of psychological time in a useful way.

You have to think, you have to use exponential notation

and abstract concepts to really get any hold

on these vast times and spaces.

On the other hand, let me hasten to add

that that doesn’t make us small

or make the time that we have to us small.

Because again, looking at those pictures

of what our minds are and some of the components

of our minds, these beautiful drawings

of the cellular patterns inside the brain,

you see that there are many, many, many processing units.

And if you analyze how fast they operate,

I tried to estimate how many thoughts

a person can have in a lifetime.

That’s kind of a fuzzy question,

but I’m very proud that I was able

to define it pretty precisely.

And it turns out we have time for billions

of meaningful thoughts in a lifetime.

So it’s a lot.

We shouldn’t think of ourselves as terribly small

either in space or in time,

because although we’re small in those dimensions

compared to the universe, we’re large compared

to meaningful units of processing information

and being able to conceptualize and understand things.

Yeah, but 99% of those thoughts are probably food,

sex, or internet related.

Well, yeah, well, they’re not necessarily, that’s right.

Only like point one is Nobel Prize winning ideas.

That’s true, but there’s more to life

than winning Nobel Prizes.

How did you do that calculate?

Can you maybe break that apart a little bit,

just kind of for fun, sort of an intuition

of how we calculate the number of thoughts?

The number of thoughts, right.

It’s necessarily imprecise because a lot of things

are going on in different ways and what is a thought.

But there are several things that point

to more or less the same rate of being able

to have meaningful thoughts.

For instance, the one that I think is maybe

the most penetrating is how fast

we can process visual images.

How do we do that?

If you’ve ever watched old movies,

you can see that, well, any movie, in fact,

a motion picture is really not a motion picture.

It’s a series of snapshots that are playing

one after the other and it’s because our brains

also work that way.

We take snapshots of the world, integrate over a certain time

and then go on to the next one and then by post processing,

create the illusion of continuity and flow,

we can deal with that.

And if the flicker rate is too slow,

then you start to see that it’s a series of snapshots

and you can ask, what is the crossover?

When does it change from being something

that is matched to our processing speed versus too fast?

And it turns out about 40 per second.

And then if you take 40 per second as how well,

how fast we can process visual images,

you get to several billions of thoughts.

If you, similarly, if you ask what are some

of the fastest things that people can do?

Well, they can play video games,

they can play the piano very fast if they’re skilled at it.

And again, you get to similar units

or how fast can people talk?

You get to similar, you know,

within a couple of orders of magnitude,

you get more or less to the same idea.

So that’s how you can say that there’s billions

of meaningful, there’s room for billions

of meaningful thoughts.

I won’t argue for exactly two billion versus 1.8 billion.

It’s not that kind of question,

but I think any estimate that’s reasonable

will come out within, say, 100 billion and 100 million.

So it’s a lot.

It would be interesting to map out

for an individual human being the landscape of thoughts

that they’ve sort of traveled.

If you think of thoughts as a set of trajectories,

what that landscape looks like.

I mean, I’ve been recently really thinking

about this Richard Dawkins idea of memes

and just all this ideas and the evolution of ideas

inside of one particular human mind

and how they’re then changed and evolved

by interaction with other human beings.

It’s interesting to think about.

So if you think the number is billions,

you think there’s also social interaction.

So these aren’t like there’s interaction

in the same way you have interaction with particles.

There’s interaction between human thoughts

that perhaps that interaction in itself

is fundamental to the process of thinking.

Like without social interaction,

we would be like stuck, like walking in a circle.

We need the perturbation of other humans

to create change and evolution.

Once you bring in concepts of interactions

and correlations and relations,

then you have what’s called a combinatorial explosion

that the number of possibilities expands exponentially

technically with the number of things you’re considering.

And it can easily rapidly outstrip these billions

of thoughts that we’re talking about.

So we definitely cannot by brute force

master complex situations

or think of all the possibilities in a complex situations.

I mean, even something as relatively simple as chess

is still something that human beings

can’t comprehend completely.

Even the best players lose, still sometimes lose

and they consistently lose to computers these days.

And in computer science, there’s a concept of NP complete.

So large classes of problems when you scale them up

beyond a few individuals become intractable.

And so that in that sense, the world is inexhaustible.

And that makes it beautiful that we can make any laws

that generalize efficiently and well

can compress all of that combinatorial complexity

just like a simple rule.

That in itself is beautiful.

It’s a happy situation.

And I think that we can find general principles

of sort of of the operating system

that are comprehensible, simple, extremely powerful

and let us control things very well

and ask profound questions.

And on the other hand,

that the world is going to be inexhaustible.

That once we start asking about relationships

and how they evolve and social interactions

and we’ll never have a theory of everything

in any meaningful sense because that.

Of everything, everything, truly everything is.

Can I ask you about the Big Bang?

So we talked about the space and time are really big.

But then, and we humans give a lot of meaning

to the word space and time in our like daily lives.

But then can we talk about this moment of beginning

and how we’re supposed to think about it?

That at the moment of the Big Bang,

everything was what, like infinitely small

and then it just blew up?

We have to be careful here

because there’s a common misconception

that the Big Bang is like the explosion of a bomb

in empty space that fills up the surrounding place.

It is space.

It is, yeah.

As we understand it, it’s the fact,

it’s the fact or the hypothesis,

but well supported up to a point

that everywhere in the whole universe,

early in the history,

matter came together into a very hot, very dense,

if you run it backwards in time,

matter comes together into a very hot, very dense

and yet very homogeneous plasma

of all the different kinds of elementary particles

and quarks and anti quarks and gluons

and photons and electrons and anti electrons,

everything, all of that stuff.

Like really hot.

Really, really, really hot.

We’re talking about way, way hotter

than the surface of the sun.

Well, in fact, if you take the equations as they come,

the prediction is that the temperature

just goes to infinity,

but then the equations break down.

We don’t really, there are various,

the equations become infinity equals infinity,

so they don’t feel that it’s called a singularity.

We don’t really know.

This is running the equations backwards,

so you can’t really get a sensible idea

of what happened before the Big Bang.

So we need different equations

to address the very earliest moments.

But so things were hotter and denser.

We don’t really know why things started out that way.

We have a lot of evidence that they did start out that way.

But since most of the,

we don’t get to visit there and do controlled experiments.

Most of the record is very, very processed

and we have to use very subtle techniques

and powerful instruments to get information

that has survived.

Get closer and closer to the Big Bang.

Get closer and closer to the beginning of things.

And what’s revealed there is that, as I said,

there undoubtedly was a period

when everything in the universe

that we have been able to look at and understand,

and that’s consistent with everything,

is in a condition where it was much, much hotter

and much, much denser,

but still obeying the laws of physics

as we know them today.

And then you start with that.

So all the matter is in equilibrium.

And then with small quantum fluctuations

and run it forward,

and then it produces, at least in broad strokes,

the universe we see around us today.

Do you think we’ll ever be able to,

with the tools of physics, with the way science is,

with the way the human mind is,

we’ll ever be able to get to the moment of the Big Bang

in our understanding or even the moment before the Big Bang?

Can we understand what happened before the Big Bang?

I’m optimistic both that we’ll be able to measure more,

so observe more,

and that we’ll be able to figure out more.

So they’re very, very tangible prospects

for observing the extremely early universe,

so even much earlier than we can observe now

through looking at gravitational waves.

Gravitational waves, since they interact so weakly

with ordinary matter,

sort of send a minimally processed signal from the Big Bang.

It’s a very weak signal

because it’s traveled a long way

and diffused over long spaces,

but people are gearing up to try to detect

gravitational waves that could have come

from the early universe.

Yeah, LIGO’s an incredible engineering project.

It’s the most sensitive, precise devices on Earth.

The fact that humans can build something like that

is truly awe inspiring from an engineering perspective.

Right, but these gravitational waves from the early universe

will probably be of a much longer wavelength

than LIGO is capable of sensing,

so there’s a beautiful project

that’s contemplated to put lasers

in different locations in the solar system.

We really, really separate it

by solar system scale differences,

like artificial planets or moons in different places

and see the tiny motions of those

relative to one another

as a signal of radiation from the Big Bang.

We can also maybe indirectly see the imprint

of gravitational waves from the early universe

on the photons, the microwave background radiation.

That is our present way of seeing into the earliest universe,

but those photons interact much more strongly with matter.

They’re much more strongly processed,

so they don’t give us directly such an unprocessed view

of the early universe, of the very early universe,

but if gravitational waves leave some imprint on that

as they move through, we could detect that too,

and people are trying, as we speak,

working very hard towards that goal.

It’s so exciting to think about a sensor

the size of the solar system.

That would be a fantastic,

I mean, that would be a pinnacle artifact

of human endeavor to me.

It would be such an inspiring thing

that just we want to know,

and we go to these extraordinary lengths

of making gigantic things that are also very sophisticated

because what you’re trying to do,

you have to understand how they move.

You have to understand the properties of light

that are being used, the interference between light,

and you have to be able to make the light with lasers

and understand the quantum theory

and get the timing exactly right.

It’s an extraordinary endeavor

involving all kinds of knowledge

from the very small to the very large,

and all in the service of curiosity

and built on a grand scale, so.

Yeah, it would make me proud to be a human if we did that.

I love that you’re inspired both by the power of theory

and the power of experiment.

So both, I think, are exceptionally impressive

that the human mind can come up with theories

that give us a peek into how the universe works,

but also construct tools that are way bigger

than the evolutionary origins we came from.

Right, and by the way,

the fact that we can design such things and they work

is an extraordinary demonstration

that we really do understand a lot.

And then in some ways.

And it’s our ability to answer questions

that also leads us to be able

to address more ambitious questions.

So you mentioned at the Big Bang in the early days,

things are pretty homogeneous.


But here we are, sitting on Earth,

two hairless apes, you could say, with microphones.

In talking about the brief history of things,

you said it’s much harder to describe Sweden

than it is the universe.

So there’s a lot of complexity.

There was a lot of interesting details here.

So how does this complexity come to be, do you think?

It seems like there’s these pockets.


We don’t know how rare of like where hairless apes emerge.


And then that came from the initial soup

that was homogeneous.

Was that an accident?

Well, we understand in broad outlines

how it could happen.

We certainly don’t understand why it happened exactly

in the way it did.

Or there are certainly open questions

about the origins of life

and how inevitable the emergence of intelligence was

and how that happened.

But in the very broadest terms,

the universe early on was quite homogeneous,

but not completely homogeneous.

There were part in 10,000 fluctuations in density

within this primordial plasma.

And as time goes on, there’s an instability

which causes those density contrasts to increase.

There’s a gravitational instability

where it’s denser, the gravitational attractions

are stronger.

And so that brings in more matter

and it gets even denser and so on and so on.

So there’s a natural tendency of matter to clump

because of gravitational interactions.

And then the equation is complicated.

We have lots of things clumping together.

Then we know what the laws are,

but we have to a certain extent wave our hands

about what happens.

But basic understanding of chemistry

says that if things and the physics of radiation

tells us that as things start to clump together,

they can radiate, give off some energy.

So they don’t just, they slow down.

As a result, they lose energy.

They can collaborate together, cool down,

form things like stars, form things like planets.

And so in broad terms, there’s no mystery.

There’s, that’s what the scenario,

that’s what the equations tell you should happen.

But because it’s a process involving

many, many fundamental individual units,

the application of the laws that govern individual units

to these things is very delicate,

computationally very difficult.

And more profoundly, the equations have

this probability of chaos or sensitivity

to initial conditions, which tells you tiny differences

in the initial state can lead to enormous differences

in the subsequent behavior.

So physics, fundamental physics at some point says,

okay, chemists, biologists, this is your problem.

And then again, in broad terms,

we know how it’s conceivable that the humans

and things like that, how complex structure can emerge.

It’s a matter of having the right kind of temperature

and the right kind of stuff.

So you need to be able to make chemical bonds

that are reasonably stable

and be able to make complex structures.

And we’re very fortunate that carbon has this ability

to make backbones and elaborate branchings and things.

So you can get complex things that we call biochemistry.

And yet the bonds can be broken a little bit

with the help of energetic injections from the sun.

So you have to have both the possibility of changing,

but also the useful degree of stability.

And we know at that very, very broad level, physics

can tell you that it’s conceivable.

If you want to know what really happened,

what really can happen, then you have to work a bit,

go to chemistry.

If you want to know what actually happened,

then you really have to consult the fossil record

and biologists.

And so these ways of addressing the issue

are complimentary in a sense.

They use different kinds of concepts,

they use different languages

and they address different kinds of questions,

but they’re not inconsistent, they’re just complimentary.

It’s kind of interesting to think about those early fluctuations

as our earliest ancestors.

Yes, that’s right.

So it’s amazing to think that this is the modern answer

to the, or the modern version of what the Hindu philosophers

had, that art thou.

If you ask what, okay, those little quantum fluctuations

in the early universe are the seeds out of which complexity,

including plausibly humans, really evolve.

You don’t need anything else.

That brings up the question of asking for a friend here

if there’s other pockets of complexity,

commonly called as alien intelligent civilizations out there.

Well, we don’t know for sure,

but I have a strong suspicion that the answer is yes

because the one case we do have at hand to study

here on Earth, we sort of know what the conditions were

that were helpful to life,

the right kind of temperature, the right kind of star

that keeps, maintains that temperature for a long time,

the liquid environment of water.

And once those conditions emerged on Earth,

which was roughly four and a half billion years ago,

it wasn’t very long before what we call life

started to leave relics.

So we can find forms of life, primitive forms of life

that are almost as old as the Earth itself

in the sense that once the Earth was turned

from a very hot boiling thing

and cooled off into a solid mass with water,

life emerged very, very quickly.

So it seems that these general conditions for life

are enough to make it happen relatively quickly.

Now, the other lesson I think that one can draw

from this one example, it’s dangerous to draw lessons

from one example, but that’s all we’ve got,

and that the emergence of intelligent life

is a different issue altogether.

That took a long time and seems to have been

pretty contingent for a long time.

Well, for most of the history of life,

it was single celled things.

Even multicellular life only rose

about 600 million years ago, so much after.

And then intelligence is kind of a luxury.

Many more kinds of creatures have big stomachs

than big brains.

In fact, most have no brains at all in any reasonable sense.

And the dinosaurs ruled for a long, long time

and some of them were pretty smart,

but they were at best bird brains

because birds came from the dinosaurs.

And it could have stayed that way.

And then the emergence of humans was very contingent

and kind of a very, very recent development

on evolutionary timescales.

And you can argue about the level of human intelligence,

but I think that’s what we’re talking about.

It’s very impressive and can ask these kinds of questions

and discuss them intelligently.

So I guess my, so this is a long winded answer

or justification of my feeling

is that the conditions for life in some form

are probably satisfied many, many places

around the universe and even within our galaxy.

I’m not so sure about the emergence of intelligent life

or the emergence of technological civilizations.

That seems much more contingent and special.

And we might, it’s conceivable to me

that we’re the only example in the galaxy.

Although, yeah, I don’t know one way or the other.

I have different opinions on different days of the week.

But one of the things that worries me

in the spirit of being humble,

that our particular kind of intelligence

is not very special.

So there’s all kinds of different intelligences.

And even more broadly,

there could be many different kinds of life.

So the basic definition, and I just had,

I think somebody that you know, Sarah Walker,

I just had a very long conversation with her

about even just the very basic question

of trying to define what is life from a physics perspective.

Even that question within itself,

I think one of the most fundamental questions

in science and physics and everything

is just trying to get a hold,

trying to get some universal laws

around the ideas of what is life

because that kind of unlocks a bunch of things

around life, intelligence, consciousness,

all those kinds of things.

I agree with you in a sense,

but I think that’s a dangerous question

because the answer can’t be any more precise

than the question.

And the question, what is life,

kind of assumes that we have a definition of life

and that it’s a natural phenomena

that can be distinguished.

But really there are edge cases like viruses

and some people would like to say

that electrons have consciousness.

So you can’t, if you really have fuzzy concepts,

it’s very hard to reach precise kinds of scientific answers.

But I think there’s a very fruitful question

that’s adjacent to it,

which has been pursued in different forms

for quite a while

and is now becoming very sophisticated

in reaching in new directions.

And that is, what are the states of matter

that are possible?

So in high school or grade school,

you learn about solids, liquids and gases,

but that really just scratches the surface

of different ways that are distinguishable,

that matter can form into macroscopically different,

meaningful patterns that we call phases.

And then there are precise definitions

of what we mean by phases of matter

and that have been worked out fruitful over the decades.

And we’re discovering new states of matter all the time

and kind of having to work at what we mean by matter.

We’re discovering the capabilities of matter

to organize in interesting ways.

And some of them, like liquid crystals,

are important ingredients of life.

Our cell membranes are liquid crystals,

and that’s very important to the way they work.

Recently, there’s been a development

in where we’re talking about states of matter

that are not static, but that have dynamics,

that have characteristic patterns,

not only in space, but in time.

These are called time crystals,

and that’s been a development

that’s just in the last decade or so.

It’s just really, really flourishing.

And so is there a state of matter

or a group of states of matter that corresponds to life?

Maybe, but the answer can’t be any more definite

than the question.

I mean, I gotta push back on the,

those are just words.

I mean, I disagree with you.

The question points to a direction.

The answer might be able to be more precise

than the question, because just as you’re saying,

there is a, we could be discovering

certain characteristics and patterns

that are associated with a certain type of matter,

macroscopically speaking,

and that we can then be able to post facto say,

this is, let’s assign the word life to this kind of matter.

I agree with that completely, that’s what that’s,

but that’s, so it’s not a disagreement.

It’s very frequent in physics that, or in science,

that words that are in common use

get refined and reprocessed into scientific terms

that’s happened for things like force and energy.

And so we, in a way, we find out

what the useful definition is, or symmetry, for instance.

And the common usage may be quite different

from the scientific usage,

but the scientific usage is special

and takes on a life of its own,

and we find out what the useful version of it is,

the fruitful version of it is.

So I do think, so in that spirit,

I think if we can identify states of matter

or linked states of matter that can carry on processes

of self reproduction and development

and information processing,

we might be tempted to classify those things as life.

Well, can I ask you about the craziest one,

which is the one we know maybe least about,

which is consciousness.

Is it possible that there are certain kinds of matter

would be able to classify as conscious,

meaning like, so there’s the panpsychists, right,

who are the philosophers who kind of try to imply

that all matter has some degree of consciousness,

and you can almost construct like a physics of consciousness.

Do you, again, we’re in such early days of this,

but nevertheless, it seems useful to talk about it.

Is there some sense from a physics perspective

to make sense of consciousness?

Is there some hope?

Well, again, consciousness is a very imprecise word

and loaded with connotations that I think we should,

we don’t wanna start a scientific analysis with that,

I don’t think.

It’s often been important in science

to start with simple cases and work up.

Consciousness, I think what most people think of

when you talk about consciousness is,

okay, what am I doing in the world?

This is my experience.

I have a rich inner life and experience,

and where is that in the equations?

And I think that’s a great question,

a great, great question,

and actually, I think I’m gearing up to spend part of,

I mean, to try to address that in coming years.

One version of asking that question,

just as you said now,

is what is the simplest formulation of that to study?

I think I’m much more comfortable

with the idea of studying self awareness

as opposed to consciousness,

because that sort of gets rid of the mystical aura of the thing.

And self awareness is in simple,

you know, I think contiguous at least

with ideas about feedback.

So if you have a system that looks at its own state

and responds to it, that’s a kind of self awareness.

And more sophisticated versions

could be like in information processing things,

computers that look into their own internal state

and do something about it.

And I think that could also be done in neural nets.

This is called recurrent neural nets,

which are hard to understand and kind of a frontier.

So I think understanding those

and gradually building up a kind of profound ability

to conceptualize different levels of self awareness.

What do you have to not know?

And what do you have to know?

And when do you know that you don’t know it?

Or when do you, what do you think you know

that you don’t really know?

And these, I think clarifying those issues,

when we clarify those issues

and get a rich theory around self awareness,

I think that will illuminate the questions

about consciousness in a way that, you know,

scratching your chin and talking about qualia

and blah, blah, blah, blah is never gonna do.

Well, I also have a different approach to the whole thing.

So there’s, from a robotics perspective,

you can engineer things that exhibit qualities

of consciousness without understanding how things work.

And from that perspective, you, it’s like a back door,

like enter through the psychology door.

Precisely, I think we’re on the same wavelength here.

I think that, and let me just add one comment,

which is I think we should try to understand consciousness

as we experience it as, in evolutionary terms,

and ask ourselves, why, why does it happen?

This thing seems useful.

Why is it useful?

Interesting question.

I think we’ve got a conscious eyewatch here.

Interesting question.

Thank you, Siri.


I’ll get back to you later.

The, and I think what we’re gonna,

I’m morally certain that what’s gonna emerge

from analyzing recurrent neural nets

and robotic design and advanced computer design

is that having this kind of looking at the internal state

in a structured way that doesn’t look at everything,

this guy’s has, it’s encapsulated,

looks at highly processed information,

is very selective and makes choices

without knowing how they’re made.

There’s, there’ll also be an unconscious.

I think that that is gonna be,

turn out to be really essential

to doing efficient information processing.

And that’s why it evolved,

because it’s, it’s, it’s, it’s helpful in,

because brains come at a high cost.

So there has to be, there has to be a good why.

And there’s a reason, yeah.

They’re rare in evolution and big brains

are rare in evolution and they, they come at a big cost.

You mean, if you, you, they, they,

they have high metabolic demands.

They require, you know, very active lifestyle,

warm bloodedness and take, take away from the ability

to support metabolism of digestion.

And so, so it’s, it’s, it comes at a high cost.

It has to, it has to pay back.

Yeah, I think it has a lot of value in social interaction.

So I actually am spending the rest of the day today

and with our friends that are,

our legged friends in robotic form at Boston Dynamics.

And I think, so my probably biggest passion

is human robot interaction.

And it seems that consciousness from the perspective

of the robot is very useful to improve

the human robot interaction experience.

The first, the display of consciousness,

but then to me, there’s a gray area

between the display of consciousness and consciousness itself.

If you think of consciousness

from an evolutionary perspective,

it seems like a useful tool in human communication, so.

Yes, it’s certainly, well,

whatever consciousness is will turn out to be.

I think addressing it through its use

and working up from simple cases

and also working up from engineering experience

in trying to do efficient computation,

including efficient management of social interactions

is going to really shed light on these questions.

As I said, in a way that sort of musing abstractly

about consciousness never would.

So as I mentioned, I talked to Sarah Walker

and first of all, she says, hi, spoke very highly of you.

One of her concerns about physics and physicists and humans

is that we may not fully understand the system

that we’re inside of.

Meaning like, there may be limits

to the kind of physics we do

in trying to understand the system of which we’re part of.

So like, the observer is also the observed.

In that sense, it seems like

our tools of understanding the world,

I mean, this is mostly centered around the questions

of what is life, trying to understand the patterns

that are characteristic of life and intelligence,

all those kinds of things.

We’re not using the right tools because we’re in the system.

Is there something that resonates with you there?

Almost like…

Well, yes, we have limitations, of course,

in the amount of information we can process.

On the other hand, we can get help from our Silicon friends

and we can get help from all kinds of instruments

that make up for our perceptual deficits.

And we can use, at a conceptual level,

we can use different kinds of concepts

to address different kinds of questions.

So I’m not sure exactly what problem she’s talking about.

It’s a problem akin to an organism living in a 2D plane

trying to understand a three dimensional world.

Well, we can do that.

I mean, in fact, for practical purposes,

most of our experience is two dimensional.

It’s hard to move vertically.

And yet we’ve produced conceptually

a three dimensional symmetry

and in fact, four dimensional space time.

So by thinking in appropriate ways and using instruments

and getting consistent accounts and rich accounts,

we find out what concepts are necessary.

And I don’t see any end in sight of the process

or any showstoppers because, let me give you an example.

I mean, for instance, QCD,

our theory of the strong interaction,

has nice equations, which I helped to discover.

What’s QCD?

Quantum chromodynamics.

So it’s our theory of the strong interaction,

the interaction that is responsible for nuclear physics.

So it’s the interaction that governs

how quarks and gluons interact with each other

and make protons and neutrons

and all the strong, the related particles

and many things in physics.

It’s one of the four basic forces of nature

as we presently understand it.

And so we have beautiful equations,

which we can test in very special circumstances

using at high energies, at accelerators.

So we’re certain that these equations are correct.

Prizes are given for it and so on.

And people try to knock it down and they can’t.

Yeah, but the situations in which we can calculate

the consequences of these equations are very limited.

So for instance, no one has been able to demonstrate

that this theory, which is built on quarks and gluons,

which no one, which you don’t observe,

actually produces protons and neutrons

and the things you do observe.

This is called the problem of confinement.

So no one’s been able to prove that analytically

in a way that a human can understand.

On the other hand, we can take these equations

to a computer, to gigantic computers and compute.

And by God, you get the world from it.

So these equations in a way that we don’t understand

in terms of human concepts, we can’t do the calculations,

but our machines can do them.

So with the help of what I like to call our silicon friends

and their descendants in the future,

we can understand in a different way

that allows us to understand more.

But I don’t think we’ll ever, no human is ever going

to be able to solve those equations in the same way.

So, but I think that’s, you know,

when we find limitations to our natural abilities,

we can try to find workarounds.

And sometimes that’s appropriate concepts.

Sometimes it’s appropriate instruments.

Sometimes it’s a combination of the two.

But I think it’s premature to get defeatist about it.

I don’t see any logical contradiction

or paradox or limitation

that will bring this process to a halt.

Well, I think the idea is to continue thinking

outside the box in different directions,

meaning just like how the math allows us

to think in multiple dimensions

outside of our perception system, sort of thinking,

you know, coming up with new tools

of mathematics or computation or all those kinds of things

to take different perspectives on our universe.

Well, I’m all for that.

You know, and I kind of have even elevated into a principle

which is of complementarity following Bohr

that you need different ways of thinking

even about the same things

in order to do justice to their reality

and answer different kinds of questions about them.

I mean, we’ve several times alluded to the fact

that human beings are hard to understand

and the concepts that you use to understand human beings

if you wanna prescribe drugs for them

or see what’s gonna happen if they move very fast

or are exposed to radiation.

And so that requires one kind of thinking

that’s very physical based on the fact

that the materials that were made out of.

On the other hand, if you want to understand

how a person’s going to behave

in a different kind of situation,

you need entirely different concepts from psychology

and there’s nothing wrong with that.

You can have very different ways

of addressing the same material

that are useful for different purposes, right?

Can you describe this idea

which is fascinating of complementarity a little bit?

Sort of first of all, what state is the principle?

What is it?

And second of all, what are good examples

starting from quantum mechanics?

You used to mention psychology.

Let’s talk about this more.

It’s like in your new book

one of the most fascinating ideas actually.

I think it’s a wonderful, yeah.

To me it’s, well, it’s the culminating chapter of the book

and I think since the whole book is about the big lessons

or big takeaways from profound understanding

of the physical world that we’ve achieved,

including that it’s mysterious in some ways,

this was the final overarching lesson, complementarity.

Lesson, complementarity and it’s a approach.

So unlike some of these other things

which are just facts about the world,

like the world is both big and small

and different sizes and is big but we’re not small,

things we talked about earlier

and the fact that the universe is comprehensible

and how complexity could emerge from simplicity

and so those things are in the broad sense

facts about the world.

Complementarity is more an attitude towards the world

than encouraged by the facts about the world.

And it’s the concept or the approach

or the realization that it can be appropriate

and useful and inevitable and unavoidable

to use very different descriptions of the same object

or the same system or the same situation

to answer different kinds of questions

that may be very different

and even mutually uninterpretable,

immutually incomprehensible.

But both correct somehow.

But both correct and sources of different kinds of insight

which is so weird.

But it seems to work in so many cases.

It works in many cases and I think it’s a deep fact

about the world and how we should approach it.

It’s most rigorous form where it’s actually a theorem

if quantum mechanics is correct,

occurs in quantum mechanics

where the primary description of the world

is in terms of wave functions.

But let’s not talk about the world.

Let’s just talk about a particle, an electron.

The primary description of that electron

is its wave function.

And the wave function can be used to predict

where it’s gonna be.

If you observe, it’ll be in different places

with different probabilities or how fast it’s moving.

And it’ll also be moving in different ways

with different probabilities.

That’s what quantum mechanics says.

And you can predict either set of probabilities

if you know what’s gonna happen

if I make an observation of the position or the velocity.

So the wave function gives you ways of doing both of those.

But to do it, to get those predictions,

you have to process the wave function in different ways.

You process it one way for position

and in a different way for momentum.

And those ways are mathematically incompatible.

It’s like you have a stone

and you can sculpt it into a Venus de Milo

or you can sculpt it into David, but you can’t do both.

And that’s an example of complementarity.

To answer different kinds of questions,

you have to analyze the system in different ways

that are mutually incompatible,

but both valid to answer different kinds of questions.

So in that case, it’s a theorem,

but I think it’s a much more widespread phenomena

that applies to many cases

where we can’t prove it as a theorem,

but it’s a piece of wisdom, if you like,

and appears to be a very important insight.

And if you ignore it,

you can get very confused and misguided.

Do you think this is a useful hack

for ideas that we don’t fully understand?

Or is this somehow a fundamental property

of all or many ideas,

that you can take multiple perspectives

and they’re both true?

Well, I think it’s both.

So it’s both the answer to all questions.

Yes, that’s right.

It’s not either or, it’s both.

It’s paralyzing to think that we live in a world

that’s fundamentally surrounded by complementary ideas.

Because we somehow want to attach ourselves

to absolute truths,

and absolute truths certainly don’t like the idea

of complementarity.

Yes, Einstein was very uncomfortable with complementarity.

And in a broad sense,

the famous Bohr Einstein debates

revolved around this question

of whether the complementarity

that is a foundational feature of quantum mechanics,

as we have it,

is a permanent feature of the universe

and our description of nature.

And so far, quantum mechanics wins.

And it’s gone from triumph to triumph.

Whether complementarity is rock bottom,

I guess, you can never be sure.

I mean, but it looks awfully good

and it’s been very successful.

And certainly, complementarity has been extremely useful

and fruitful in that domain,

including some of Einstein’s attempts to challenge it

with the famous Einstein Podolsky Rosen experiment

turned out to be confirmations

that have been useful in themselves.

But so thinking about these things was fruitful,

but not in the way that Einstein hoped.

Yeah, so as I said, in the case of quantum mechanics

and this dilemma or dichotomy

between processing the wave function in different ways,

it’s a theorem.

They’re mutually incompatible

and the physical correlate of that

is the Heisenberg uncertainty principle

you can’t have position and momentum determined at once.

But in other cases, like one that I like to think about

or like to point out as an example

is free will and determinism.

It’s much less of a theorem

and more a kind of way of thinking about things

that I think is reassuring

and avoids a lot of unnecessary quarreling and confusion.

The quarreling I’m okay with

and the confusion I’m okay with,

I mean, people debate about difficult ideas,

but the question is whether it could be

almost a fundamental truth.

I think it is a fundamental truth.

That free will is both an illusion and not.

Yes, I think that’s correct.

There’s a reason why people say quantum mechanics is weird

and complementarity is a big part of that.

To say that our actual whole world is weird,

the whole hierarchy of the universe is weird

in this kind of particular way,

and it’s quite profound, but it’s also humbling

because it’s like we’re never going to be on sturdy ground

in the way that humans like to be.

It’s like you have to embrace that this whole thing

is like unsteady mess.

It’s one of many lessons in humility

that we run into in profound understanding of the world.

The Copernican revolution was one,

that the earth is not the center of the universe.

Darwinian evolution is another,

that humans are not the pinnacle of God’s creation and the apparent result

of deep understanding of physical reality,

that mind emerges from matter and there’s no call

on special life forces or souls.

These are all lessons in humility,

and I actually find complementarity a liberating concept.

It’s, okay, you know, we…

Yeah, it is in a way.

That is what I remember.

There’s a story about Dr. Johnson,

and he’s talking with Boswell,

and Boswell was, they were discussing a sermon

that they’d both heard,

and the sort of culmination of the sermon was the speaker saying,

I accept the universe.

And Dr. Johnson said, well, damn well better.

And there’s a certain joy in accepting the universe

because it’s mind expanding.

And to me, complementarity also suggests tolerance,

suggests opportunities for understanding things

in different ways that add to rather than detract

from understanding.

So I think it’s an opportunity for mind expansion

and demanding that there’s only one way

to think about things can be very limiting.

On the free will one, that’s a trippy one, though.

To think like I am the decider of my own actions

and at the same time I’m not is tricky to think about,

but there does seem to be some kind of profound truth in that.

I get, well, I think it is tied up.

It will turn out to be tied up when we understand things better

with these issues of self awareness and where we get,

what we perceive as making choices,

what does that really mean and what’s going on under the hood.

But I’m speculating about a future understanding

that’s not in place at present.

Your sense there will always be,

like as you dig into the self awareness thing,

there’ll always be some places

where complementarity is gonna show up.

Oh, definitely, yeah.

I mean, there will be, how should I say?

There’ll be kind of a God’s eye view

which sees everything that’s going on

in the computer or the brain.

And then there’s the brain’s own view

or the central processor or whatever it is,

what we call the self, the consciousness,

that’s only aware of a very small part of it.

And those are very different.

Those are, so the God’s eye view can be deterministic

while the self view sees free will.

I’m pretty sure that’s how it’s gonna work out actually.

But as it stands, free will is a concept

that we definitely, at least I feel I definitely experience,

I can choose to do one thing then another.

And other people I think are sufficiently similar to me

that I trust that they feel the same way.

And it’s an essential concept in psychology

and law and so forth.

But at the same time, I think that mind emerges from matter

and that there’s an alternative description of matter

that’s up to subtleties about quantum mechanics,

which I don’t think are relevant here,

really is deterministic.

Let me ask you about some particles.


First the absurd question,

almost like a question that like Plato would ask.

What is the smallest thing in the universe?

As far as we know, the fundamental particles

out of which we build our most successful description

of nature are points.

They don’t have any internal structure.

So that’s as small as can be.

So what does that mean operationally?

That means that they obey equations that describe entities

that are singular concentrations of energy,

momentum, angular momentum,

the things that particles have,

but localized at individual points.

Now that mathematical structure

is only revealed partially in the world

because to process the wave function

in a way that accesses information about the precise

position of things, you have to apply a lot of energy

and that’s an idealization

and you can apply infinite amount of energy

to determine a precise position.

But at the mathematical level,

we build the world out of particles that are points.

So do they actually exist and what are we talking about?

Oh, they exist.

So let me ask sort of do quarks exist?

Yes, do electrons exist?

Yes, do photons exist?


But what does it mean for them to exist?

Okay, so well, the hard answer to that,

the precise answer is that we construct the world

out of equations that contain entities

that are reproducible,

that exist in vast numbers throughout the universe,

that have definite properties of mass,

spin and a few others that we call electrons

and what an electron is is defined by the equations

that it satisfies theoretically

and we find that there are many, many exemplars

of that entity in the physical world.

So in the case of electrons,

we can isolate them and study them

and individual ones in great detail

and we can check that they all actually are identical

and that’s why chemistry works and yes.

So in that case, it’s very tangible.

Similarly with photons,

you can study them individually, the units of light

and nowadays, it’s very practical

to study individual photons

and determine their spin and their other basic properties

and check out the equations in great detail.

For quarks and gluons,

which are the other two main ingredients

of our model of matter that’s so successful,

it’s a little more complicated

because the quarks and gluons that appear in our equations

don’t appear directly as particles you can isolate

and study individually.

They always occur within what are called bound states

or structures like protons.

A proton, roughly speaking, is composed of three quarks

and a lot of gluons but we can detect them

in a remarkably direct way actually nowadays,

whereas at relatively low energies,

the behavior of quarks is complicated.

At high energies, they can propagate through space

relatively freely for a while and we can see their tracks.

So ultimately, they get recaptured into protons

and other mesons and funny things

but for a short time, they propagate freely

and while that happens, we can take snapshots

and see their manifestations.

Actually, this kind of thing is exactly

what I got the Nobel Prize for,

predicting that this would work.

And similarly for gluons,

although you can’t isolate them as individual particles

and study them in the same way that we study electrons,

say, you can use them theoretically as entities

out of which you build tangible things

that we actually do observe

but also you can, at accelerators at high energy,

you can liberate them for brief periods of time

and study and get convincing evidence

that they leave tracks and you can get convincing evidence

that they were there and have the properties

that we wanted them to have.

Can we talk about asymptotic freedom,

this very idea that you won the Nobel Prize for?


So it describes a very weird effect to me,

the weird in the following way.

So the way I think of most forces or interactions,

the closer you are, the stronger the effect,

the stronger the force, right?

With quarks, the close they are,

the less so the strong interaction.

And in fact, they’re basically act like free particles

when they’re very close.

That’s right, yes.

But this requires a huge amount of energy.

Like can you describe me why, how does this even work?

How weird it is?

A proper description must bring in quantum mechanics

and relativity and it’s,

so a proper description and equations,

so a proper description really is probably more

than we have time for and require quite a bit of patience

on your part, but.

How does relativity come into play?

Wait, wait a minute.

Relativity is important because when we talk about

trying to think about short distances,

we have to think about very large momenta

and very large momenta are connected

to very large energy in relativity.

And so the connection between how things behave

at short distances and how things behave at high energy

really is connected through relativity

in sort of a slightly backhanded way.

Quantum mechanics indicates that short,

to get to analyze short distances,

you need to bring in probes that carry a lot of momentum.

This again is related to uncertainty

because it’s the fact that you have to bring in

a lot of momentum that interferes with the possibility

of determining position and momentum at the same time.

If you want to determine position,

you have to use instruments that bring in a lot of momentum.

And because of that, those same instruments

can’t also measure momentum

because they’re disturbing the momentum that,

and then the momentum brings in energy and yeah.

So that there’s also the effect that asymptotic freedom

comes from the possibility of spontaneously making

quarks and gluons for short amounts of time

that fluctuate into existence and out of existence.

And the fact that that can be done

with a very little amount of energy

and uncertainty and energy translates

into uncertainty and time.

So if you do that for a short time, you can do that.

Well, it’s all comes in a package.

So I told you it would take a while to really explain,

but the results can be understood.

I mean, we can state the results pretty simply, I think.

So in everyday life, we do encounter some forces

that increase with distance

and kind of turn off at short distances.

That’s the way rubber bands work, if you think about it,

or if you pull them hard, they resist,

but they get flabby if the rubber band is not pulled.

And so there are, that can happen in the physical world,

but what’s really difficult is to see

how that could be a fundamental force

that’s consistent with everything else we know.

And that’s what asymptotic freedom is.

It says that there’s a very particular kind

of fundamental force that involves special particles

called gluons with very special properties

that enables that kind of behavior.

So there were experiment, at the time we did our work,

there were experimental indications

that quarks and gluons did have this kind of property,

but there were no equations

that were capable of capturing it.

And we found the equations and showed how they work

and showed how they, that they were basically unique.

And this led to a complete theory

of how the strong interaction works,

which is the quantum chromodynamics we mentioned earlier.

And so that’s the phenomenon that quarks and gluons

interact very, very weakly when they’re close together.

That’s connected through relativity

with the fact that they also interact very, very weakly

at high energies.

So if you have, so at high energies,

the simplicity of the fundamental interaction gets revealed.

At the time we did our work,

the clues were very subtle,

but nowadays at what are now high energy accelerators,

it’s all obvious.

So we would have had a much,

well, somebody would have had a much easier time

20 years later, looking at the data,

you can sort of see the quarks and gluons.

As I mentioned, they leave these short tracks

that would have been much, much easier,

but from fundamental, from indirect clues,

we were able to piece together enough

to make that behavior a prediction

rather than a post diction, right?

So it becomes obvious at high energies.

It becomes very obvious.

When we first did this work,

it was frontiers of high energy physics

and at big international conferences,

there would always be sessions on testing QCD

and whether this proposed description

of the strong interaction was in fact correct and so forth.

And it was very exciting.

But nowadays the same kind of work,

but much more precise with calculations

to more accuracy and experiments

that are much more precise

and comparisons that are very precise.

Now it’s called calculating backgrounds

because people take this for granted

and wanna see deviations from the theory,

which would be the new discoveries.

Yeah, the cutting edge becomes a foundation

and the foundation becomes boring.


Is there some, for basic explanation purposes,

is there something to be said about strong interactions

in the context of the strong nuclear force

for the attraction between protons and neutrons

versus the interaction between quarks within protons?

Well, quarks and gluons have the same relation

basically to nuclear physics

as electrons and photons have

to atomic and molecular physics.

So atoms and photons are the dynamic entities

that really come into play in chemistry and atomic physics.

Of course, you have to have the atomic nuclei,

but those are small and relatively inert,

really the dynamical part.

And for most purposes of chemistry,

you just say that you have this tiny little nucleus,

which QCD gives you.

Don’t worry about it.

It just, it’s there.

The real action is the electrons moving around

and exchanging and things like that.

Okay, but we want it to understand the nucleus too.

And so atoms are sort of quantum mechanical clouds

of electrons held together by electrical forces,

which is photons.

And then this radiation,

which is another aspect of photons.

That’s where all the fun happens

is the electrons and the photons.

Yeah, that’s right.

And the nucleus are kind of the,

well, they give the positive charge

and most of the mass of matter,

but they don’t, since they’re so heavy,

they don’t move very much in chemistry.

And I’m oversimplifying drastically.

They’re not contributing much to the interaction in chemistry.

For most purposes in chemistry,

you can just idealize them as concentrations

of positive mass and charge that are,

you don’t have to look inside,

but people are curious what’s inside.

And that was a big thing on the agenda

of 20th century physics starting in the 19,

well, starting with the 20th century

and unfolding throughout of trying to understand

what forces held the atomic nucleus together,

what it was and so.

Anyway, the story that emerges from QCD

is that very similar to the way that,

well, broadly similar to the way

that clouds of electrons held together

by electrical forces give you atoms

and ultimately molecules.

Protons and neutrons are like atoms

made now out of quarks, quark clouds held together

by gluons, which are like the photons

that give the electric forces,

but this is giving a different force, the strong force.

And the residual forces between protons and neutrons

that are leftover from the basic binding

are like the residual forces between atoms

that give molecules, but in the case of protons and neutrons,

it gives you atomic nuclei.

So again, for definitional purposes,

QCD, quantum chromodynamics,

is basically the physics of strong interaction.

Yeah, we understand, we now would understand,

I think most physicists would say

it’s the theory of quarks and gluons

and how they interact.

But it’s a very precise, and I think it’s fair to say,

very beautiful theory based on mathematical symmetry

of a high order, and another thing that’s beautiful

about it is that it’s kind of

in the same family as electrodynamics.

The conceptual structure of the equations are very similar.

They’re based on having particles that respond to charge

in a very symmetric way.

In the case of electrodynamics,

it’s photons that respond to electric charge.

In the case of quantum chromodynamics,

there are three kinds of charge that we call colors,

but they’re nothing like colors.

They really are like different kinds of charge.

But they rhyme with the same kind of,

like it’s similar kind of dynamics.

Similar kind of dynamics.

I’d like to say that QCD is like QED on steroids.

And instead of one photon, you have eight gluons.

Instead of one charge, you have three color charges.

But there’s a strong family resemblance between them.

But the context in which QCD does this thing

is it’s much higher energies.

Like that’s where it comes to life.

Well, it’s a stronger force,

so that to access how it works and kind of pry things apart,

you have to inject more energy.

And so that gives us, in some sense,

a hint of how things were in the earlier universe.

Yeah, well, in that regard,

asymptotic freedom is a tremendous blessing

because it means things get simpler at high energy.

The universe was born free.

Born free.

That’s very good, yes.

Universe was born.

So in atomic physics,

a similar thing happens in the theory of stars.

Stars are hot enough that the interactions

between electrons and photons, they’re liberated.

They don’t form atoms anymore.

They make a plasma,

which in some ways is simpler to understand.

You don’t have complicated chemistry.

And in the early universe, according to QCD,

similarly atomic nuclei dissolved

and take the constituent quarks and gluons,

which are moving around very fast

and interacting in relatively simple ways.

And so this opened up the early universe

to scientific calculation.

Can I ask you about some other weird particles

that make up our universe?

What are axions?

And what is the strong CP problem?

Okay, so let me start with what the strong CP problem is.

First of all, well, C is charge conjugation,

which is the transformation,

the notional transformation, if you like,

that changes all particles into their antiparticles.

And the concept of C symmetry,

charge conjugation symmetry, is that if you do that,

you find the same laws that would work.

So the laws are symmetric if the behavior

that particles exhibit is the same

as the behavior you get with all their antiparticles.

And then P is parity,

which is also called spatial inversion.

It’s basically looking at a mirror universe

and saying that the laws that are obeyed

in a mirror universe, when you look,

that the mirror images obey the same laws

as the sources of their images.

There’s no way of telling left from right, for instance,

that the laws don’t distinguish between left and right.

Now, in the mid 20th century,

people discovered that both of those are not quite true.

Really, the equation that the mirror universe,

the universe that you see in a mirror

is not gonna obey the same laws

as the universe that we actually interpret.

You would be able to tell

if you did the right kind of experiments,

which was the mirror and which was the real thing.

Anyway, that.

That’s the parity and they show

that the parity doesn’t necessarily hold.

It doesn’t quite hold.

Examining what the exceptions are turned out to be,

to lead to all kinds of insight

about the nature of fundamental interactions,

especially properties of neutrinos

and the weak interaction, it’s a long story.

But it’s a very, it’s a.

So you just define the C and the P,

the conjugation, the charge conjugation.

Now that I’ve done that, I wanna.

What’s the problem?

Shove them off.

Okay, great.

Because it’s easier to talk about T,

which is time reversal symmetry.

We have very good reasons to think CPT

is an accurate symmetry of nature.

It’s on the same level as relativity

and quantum mechanics, basically.

So that better be true.

Or else we.

So it’s symmetric when you.

When you do.

When you do conjugation parity and time.

And time and space reversal.

If you do all three,

then you get the same physical consequences.

Now, so, but that means that CP is equivalent to T.

But what’s observed in the world

is that T is not quite an accurate symmetry of nature,


So most phenomena of, at the fundamental level.

So interactions among elementary particles

and the basic gravitational interaction.

If you ran them backwards in time,

you’d get the same laws.

So if, again, going back.

This time we don’t talk about a mirror,

but we talk about a movie.

If you take a movie and then run it backwards,

that’s the time reversal.

It’s good to think about a mirror in time.

Yeah, it’s like a mirror in time.

If you run the movie backwards,

it would look very strange

if you were looking at complicated objects

and a Charlie Chaplin movie or whatever.

It would look very strange if you ran it backwards in time.

But at the level of basic interactions,

if you were able to look at the atoms

and the quarks involved, they would obey the same laws.

They do a very good approximation, but not exactly.

So this is not exactly, that means you could tell.

You could tell, but you’d have to do very, very

subtle experiments with at high energy accelerators

to take a movie that looked different

when you ran it backwards.

This was a discovery by two great physicists

named Jim Cronin and Val Fitch in the mid 1960s.

Previous to that, over all the centuries

of development of physics with all its precise laws,

they did seem to have this gratuitous property

that they look the same if you run the equations backwards.

It’s kind of an embarrassing property actually

because life isn’t like that.

So empirical reality does not have this imagery

in any obvious way.

And yet the laws did.

It’s almost like the laws of physics

are missing something fundamental about life

if it holds that property, right?

Well, that’s the embarrassing nature of it.

Yeah, it’s embarrassing.

Well, people worked hard at what’s,

this is a problem that’s thought to belong

to the foundations of statistical mechanics

or the foundations of thermodynamics

to understand how behavior,

which is grossly not symmetric

with respect to reversing the direction of time

in large objects, how that can emerge from equations

which are symmetric with respect to changing

the direction of time to a very good approximation.

And that’s still an interesting endeavor.

That’s interesting.

And actually it’s an exciting frontier of physics now

to sort of explore the boundary

between when that’s true and when it’s not true.

When you get to smaller objects

and exceptions like time crystals.

I definitely have to ask you about time crystals

in a second here.

But so the CP problem and T,

so there’s all of these.

We’re in danger of infinite regress,

but we have to convert soon.


Can’t possibly be turtles all the way down.

We’re gonna get to the bottom turtle.

So it became,

so it got to be a real,

I mean, it’s a really puzzling thing

why the laws should have this very odd property

that we don’t need.

And in fact, it’s kind of an embarrassment

in addressing empirical reality.

But it seemed to be almost,

it seemed to be exactly true for a long time.

And then almost true.

And in way, almost true is even,

is more disturbing than exactly true

because exactly true,

it could have been just a fundamental feature of the world.

And at some level you just have to take it as it is.

And if it’s a beautiful, easily articulatable regularity,

you could say that, okay,

that’s fine as a fundamental law of nature.

But to say that it’s approximately true,

but not exactly, that’s weird.

So, and then, so there was great progress

in the late part of the 20th century

in getting to an understanding

of fundamental interactions in general

that shed light on this issue.

It turns out that the basic principles of relativity

and quantum mechanics,

plus the kind of high degree of symmetry that we found,

the so called gauge symmetry

that characterizes the fundamental interactions,

when you put all that together,

it’s a very, very constraining framework.

And it has some indirect consequences

because the possible interactions are so constrained.

And one of the indirect consequences

is that the possibilities for violating the symmetry

between forwards and backwards in time are very limited.

They’re basically only two.

And one of them occurs and leads to a very rich theory

that explains the Cronin Fish experiment

and a lot of things that have been done subsequently

has been used to make all kinds of successful predictions.

So that’s turned out to be a very rich interaction.

It’s esoteric and the effects only show up at accelerators

and are small and so on,

but they might’ve been very important in the early universe

and lead to them be connected to the asymmetry

between matter and antimatter in the present universe.

And so, but that’s another digression.

The point is that that was fine.

That was a triumph to say

that there was one possible kind of interaction

that would violate time reversal symmetry.

And sure enough, there it is.

But the other kind doesn’t occur.

So we still got a problem.

Why doesn’t it occur?

So we’re close to really finally understanding

this profound gratuitous feature of the world

that is almost but not quite symmetric

under reversing the direction of time, but not quite there.

And to understand that last bit

is a challenging frontier of physics today.

And we have a promising proposal for how it works,

which is a kind of theory of evolution.

So there’s this possible interaction,

which we call a coupling,

and there’s a numerical quantity

that tells us how strong that is.

And traditionally in physics,

we think of these kinds of numerical quantities

as constants of nature that you just have to put them in.

From experiment, they have a certain value and that’s it.

And who am I to question what God doing?

They’re just constant.

Well, they seem to be just constants.

I’m just wondering.

But in this case,

it’s been fruitful to think and work out a theory

where that strength of interaction

is actually not a constant.

It’s a fun, it’s a field.

It’s a, fields are the fundamental ingredients

of modern physics.

Like there’s an electron field,

there’s a photon field,

which is also called the electromagnetic field.

And so all of these particles

are manifestations of different fields.

And there could be a field,

something that depends on space and time.

So a dynamical entity instead of just a constant here.

And if you do things in a nice way,

that’s very symmetric,

very much suggested aesthetically by the theory.

But the theory we do have,

then you find that you get a field

which as it evolves from the early universe,

settles down to a value

that’s just right to make the laws

very nearly exact, invariant or symmetric

with respect to reversal of time.

It might appear as a constant,

but it’s actually a field that evolved over time.

It evolved over time, okay.

But when you examine this proposal in detail,

you find that it hasn’t quite settled down to exactly zero.

There it’s still,

the field is still moving around a little bit.

And because the motion is so,

the motion is so difficult.

The material is so rigid.

And this material,

the field that fills all space is so rigid.

Even small amounts of motion can involve lots of energy.

And that energy takes the form of particles,

fields that are in motion

are always associated with particles.

And those are the axioms.

And if you calculate how much energy

is in these residual oscillations,

this axiom gas that fills all the universe,

if this fundamental theory is correct,

you get just the right amount

to make the dark matter that astronomers want.

And it has just the right properties.

So I’d love to believe that.

So that might be a thing that unlocks,

might be the key to understanding dark matter.

Yeah, I’d like to think so.

And many, many physicists are coming around

to this point of view,

which I’ve been a voice in the wilderness.

I was a voice in the wilderness for a long time,

but now it’s become very popular, maybe even dominant.

So almost like,

so this axion particle slash field

would be the thing that explains dark matter.

It explains, yeah,

would solve this fundamental question of finally,

of why the laws are almost, but not quite exactly the same

if you run them backwards in time.

And then seemingly in a totally different

conceptual universe,

it would also provide,

give us an understanding of the dark matter.

That’s not what it was designed for.

And the theory wasn’t proposed with that in mind,

but when you work out the equations, that’s what you get.

That’s always a good sign.


I think I vaguely read somewhere

that there may be early experimental validation of axion.

Is that, am I reading the wrong?

Well, there’ve been quite a few false alarms

and I think there are some of them still,

people desperately wanna find this thing.

And, but I don’t think any of them are convincing

at this point,

but there are very ambitious experiments

and kind of new,

you have to design new kinds of antennas

that are capable of detecting these predicted particles.

And it’s very difficult.

They interact very, very weakly.

If it were easy, it would have been done already.

But I think there’s good hope

that we can get down to the required sensitivity

and actually test whether these ideas are right

in coming years or maybe decades.

And then understand one of the big mysteries,

like literally big in terms of its fraction

of the universe is dark matter.


Let me ask you about, you mentioned a few times,

time crystals.

What are they?

These things are, it’s a very beautiful idea

when we start to treat space and time

as similar frameworks.

Yes, right.

Physical phenomena.

Right, that’s what motivated it.

First of all, what are crystals?


And what are time crystals?

Okay, so crystals are orderly arrangements

of atoms in space.

And many materials,

if you cool them down gently, will form crystals.

And so we say that that’s a state of matter

that forms spontaneously.

And an important feature of that state of matter

is that the end result, the crystal,

has less symmetry than the equations

that give rise to the crystal.

So the equations, the basic equations of physics

are the same if you move a little bit.

So you can move, they’re homogeneous,

but crystals aren’t.

The atoms are in particular place,

so they have less symmetry.

And time crystals are the same thing in time, basically.

But of course, so it’s not positions of atoms,

but it’s orderly behavior that certain states of matter

will arrange themselves into spontaneously

if you treat them gently

and let them do what they want to do.

But repeat in that same way indefinitely.

That’s the crystalline form.

You can also have time liquids,

or you can have all kinds of other states of matter.

You can also have space time crystals

where the pattern only repeats if with each step of time,

you also move at a certain direction in space.

So yeah, basically it’s states of matter

that displace structure in time spontaneously.

So here’s the difference.

When it happens in time,

it sure looks a lot like it’s motion,

and if it repeats indefinitely,

it sure looks a lot like perpetual motion.


Like looks like free lunch.

And I was told that there’s no such thing as free lunch.

Does this violate laws of thermodynamics?

No, but it requires a critical examination

of the laws of thermodynamics.

I mean, let me say on background

that the laws of thermodynamics

are not fundamental laws of physics.

There are things we prove

under certain circumstances emerge

from the fundamental laws of physics.

They’re not, we don’t posit them separately.

They’re meant to be deduced,

and they can be deduced under limited circumstances,

but not necessarily universally.

And we’re finding some of the subtleties

and sort of accept edge cases

where they don’t apply in a straightforward way.

And this is one.

So time crystals do obey,

do have this structure in time,

but it’s not a free lunch

because although in a sense, things are moving,

they’re already doing what they want to do.

They’re in the,

so if you want to extract energy from it,

you’re gonna be foiled

because there’s no spare energy there.

So you can add energy to it and kind of disturb it,

but you can’t extract energy from this motion

because it’s gonna, it wants to do,

that’s the lowest energy configuration that there is,

so you can’t get further energy out of it.

So in theory, I guess perpetual motion,

you would be able to extract energy from it

if such a thing was to be created,

you can then milk it for energy.

Well, what’s usually meant

in the literature of perpetual motion

is a kind of macroscopic motion

that you could extract energy from

and somehow it would crank back up.

That’s not the case here.

If you want to extract energy,

this motion is not something you can extract energy from.

If you intervene in the behavior,

you can change it, but only by injecting energy,

not by taking away energy.

You mentioned that a theory of everything

may be quite difficult to come by.

A theory of everything broadly defined

meaning like truly a theory of everything,

but let’s look at a more narrow theory of everything,

which is the way it’s used often in physics

is a theory that unifies our current laws of physics,

general relativity, quantum field theory.

Do you have thoughts on this dream

of a theory of everything in physics?

How close are we?

Is there any promising ideas out there in your view?

Well, it would be nice to have.

It would be aesthetically pleasing.

Will it be useful?

No, probably not.

Well, I shouldn’t, it’s dangerous to say that,

but probably not.

I think we, certainly not in the foreseeable future.

Maybe to understand black holes.

Yeah, but that’s, yes, maybe to understand black holes,

but that’s not useful.

That’s my book.

And well, not only, I mean,

to understand it’s worse,

it’s not useful in the sense

that we’re not gonna be basing any technology anytime soon

on black holes, but it’s more severe than that,

I would say it’s that the kinds of questions

about black holes that we can’t answer

within the framework of existing theory

are ones that are not going to be susceptible

to astronomical observation in the foreseeable future.

They’re questions about very, very small black holes

when quantum effects come into play

so that black holes are,

not black holes, they’re emitting this discovery

of Hawking called Hawking radiation,

which for astronomical black holes is a tiny, tiny effect

that no one has ever observed, it’s a prediction

that’s never been checked.

So like supermassive black holes, that doesn’t apply?

No, no, the predicted rate of radiation

from those black holes is so tiny

that it’s absolutely unobservable

and is overwhelmed by all kinds of other effects.

So it’s not practical in the sense of technology,

it’s not even practical in the sense

of application to astronomy, our existing theory

of general relativity and quantum theory

and our theory of the different fundamental forces

is perfectly adequate to all problems of technology,

of technology, for sure, and almost all problems

of astrophysics and cosmology that appear

except with the notable exception

of the extremely early universe, if you want to ask,

what happened before the Big Bang

or what happened right at the Big Bang,

which would be a great thing to understand, of course.

Yes. We don’t, but.

But what about the engineering question?

So if we look at space travel,

so I think you’ve spoken with him, Eric Weinstein.

Oh, yeah. Really, you know,

he says things like we want to get off this planet.

His intuition is almost motivated

for the engineering project of space exploration

in order for us to crack this problem

of becoming a multi planetary species,

we have to solve the physics problem.

His intuition is like, if we figure out this,

what he calls the source code, which is like,

like a theory of everything might give us clues

on how to start hacking the fabric of reality,

like getting shortcuts, right?

It might. I can’t say that, you know,

I can’t say that it won’t,

but I can say that in the 1970s and early 1980s,

we achieved huge steps in understanding matter.

QCD, much better understanding of the weak interaction,

much better understanding of quantum mechanics in general.

And it’s had minimal impact on technology.

On rocket design, on propulsion.

On rocket design, on anything, any technology whatsoever.

And now we’re talking about much more esoteric things.

And since I don’t know what they are,

I can’t say for sure that they won’t affect technology,

but I’m very, very skeptical

that they would affect technology.

Because, you know, to access them,

you need very exotic circumstances

to make new kinds of particles with high energy.

You need accelerators that are very expensive

and you don’t produce many of them, and so forth.

You know, it’s just, it’s a pipe dream, I think.

Yeah, about space exploration.

I’m not sure exactly what he has in mind,

but to me, it’s more a problem of,

I don’t know, something between biology and…

And information processing.

Processing, what you mean, how should I…

I think human bodies are not well adapted to space.

Even Mars, which is the closest thing

to a kind of human environment

that we’re gonna find anywhere close by.

Very, very difficult to maintain humans on Mars.

And it’s gonna be very expensive and very unstable.

But I think, however, if we take a broader view

of what it means to bring human civilization

outside of the Earth, if we’re satisfied

with sending mines out there that we can converse with

and actuators that we can manipulate

and sensors that we can get feedback from,

I think that’s where it’s at.

And I think that’s so much more realistic.

And I think that’s the long term future

of space exploration.

It’s not hauling human bodies all over the place.

That’s just silly.

It’s possible that human bodies…

So like you said, it’s a biology problem.

What’s possible is that we extend human life span

in some way, we have to look at a bigger picture.

It could be just like you’re saying,

by sending robots with actuators

and kind of extending our limbs.

But it could also be extending some aspect of our minds,

some information, all those kinds of things.

And it could be cyborgs, it could be, it could be…

No, we’re talking, not getting the fun.

It could be, you know, it could be human brains

or cells that realize something

like human brain architecture

within artificial environments,

you know, shells, if you like,

that are more adapted to the conditions of space.

And that, yeah, so that’s entirely man machine hybrids,

as well as sort of remote outposts

that we can communicate with.

I think those will happen.

Yeah, to me, there’s some sense in which,

as opposed to understanding the physics

of the fundamental fabric of the universe,

I think getting to the physics of life,

the physics of intelligence,

the physics of consciousness will,

the physics of information that brings,

from which life emerges,

that will allow us to do space exploration.

Yeah, well, I think physics in the larger sense

has a lot to contribute here.

Not the physics of finding fundamental new laws

in the sense of another quark or axions even.

But physics in the sense of,

physics has a lot of experience

in analyzing complex situations

and analyzing new states of matter

and devising new kinds of instruments

that do clever things.

Physics in that sense has enormous amounts

to contribute to this kind of endeavor.

But I don’t think that looking

for a so called theory of everything

has much to do with it at all.

What advice would you give to a young person today

with a bit of fire in their eyes,

high school student, college student,

thinking about what to do with their life,

maybe advice about career or bigger advice

about life in general?

Well, first read fundamentals

because there I’ve tried to give some coherent deep advice.

That’s fundamentals, 10 keys to reality by Frank Kulczyk.

So that’s a good place to start.

Available everywhere.

If you wanna learn what I can tell you.

Is there an audio book?

I read that ebook.

Yes, there is an audio book.

There’s an audio book, that’s awesome.

I think it’s, I can give three pieces of wise advice

that I think are generally applicable.

One is to cast a wide net,

to really look around and see what looks promising,

what catches your imagination and promising.

Yeah, and those, you have to balance those two things.

You could have things that catch your imagination,

but don’t look promising in the sense

that the questions aren’t ripe or,

and things that you,

and part of what makes things attractive is that,

whether you thought you liked them or not,

is if you can see that there’s ferment

and new ideas coming up that become,

that’s attractive in itself.

So when I started out, I thought I was,

and when I was an undergraduate,

I intended to study philosophy

or questions of how mind emerges from matter.

But I thought that that wasn’t really right.

Timing isn’t right yet.

The right, the timing wasn’t right

for the kind of mathematical thinking

and conceptualization that I really enjoy and am good at.

But, so that’s one thing, cast a wide net, look around.

And that’s a pretty easy thing to do today

because of the internet.

You can look at all kinds of things.

You have to be careful though

because there’s a lot of crap also.

But you can sort of tell the difference

if you do a little digging.

So don’t settle on just,

what your thesis advisor tells you to do

or what your teacher tells you to do.

Look for yourself and get a sense of what seems promising,

not what seemed promising 10 years ago or, so that’s one.

Another thing is to, is kind of complimentary to that.

Well, they’re all complimentary.

Complimentary to that is to read history

and read the masters,

the history of ideas and masters of ideas.

I’d benefited enormously from, as early in my career,

from reading in physics, Einstein in the original

and Feynman’s lectures as they were coming out and Darwin.

You know, these, you can learn what it, and Galileo,

you can learn what it is to wrestle with difficult ideas

and how great minds did that.

You can learn a lot about style,

how to write your ideas up and express them in clear ways.

And also just a couple of that with,

I also enjoy reading biographies.

And biographies, yes, similarly, right, yeah.

So it gives you the context of the human being

that created those ideas.

Right, and brings it down to earth in the sense that,

you know, it was really human beings who did this.

It’s not, and they made mistakes.

And yeah, I also got inspiration from Bertrand Russell

who was a big hero and H.G. Wells and yeah.

So read the masters, make contact with great minds.

And when you are sort of narrowing down on a subject,

learn about the history of the subject

because that really puts in context

what you’re trying to do and also gives a sense of community

and grandeur to the whole enterprise.

And then the third piece of advice

is complimentary to both those,

which is sort of to get the basics under control

as soon as possible.

So if you wanna do theoretical work in science,

you know, you have to learn calculus,

multivariable calculus, complex variables, group theory.

Nowadays, you have to be highly computer literate

if you want to do experimental work.

You also have to be computer literate

and you have to learn about electronics

and optics and instruments.

So get that under control as soon as possible

because it’s like learning a language to produce great works

and express yourself fluently and with confidence.

It should be your native language.

These things should be like your native language.

So you’re not wondering what is the derivative?

This is just part of your, it’s in your bones,

so to speak, and the sooner that you can do that,

then the better.

So all those things can be done in parallel and should be.

You’ve accomplished some incredible things in your life,

but the sad thing about this thing we have is it ends.

Do you think about your mortality?

Are you afraid of death?

Well, afraid is the wrong word.

I mean, I wish it weren’t going to happen

and I’d like to, but.

Do you think about it?

I, you know, occasionally I think about,

well, I think about it very operationally

in the sense that there’s always a trade off

between exploration and exploitation.

This is a classic subject in computer science,

actually in machine learning that when you’re

in an unusual circumstance, you want to explore

to see what the landscape is and what, and gather data.

But then at some point you want to use that,

make, decide, make choices and say,

this is what I’m going to do and exploit the knowledge

you’ve accumulated.

And the longer the period of exploitation you anticipate,

the more exploration you should do in new directions.

And so for me, I’ve had to sort of adjust the balance

of exploration and exploitation and.

That’s it, you’ve explored quite a lot.

Yeah, well, I haven’t shut off the exploitation at all.

I’m still hoping for. The exploration.

The exploration, right.

I’m still hoping for 10 or 15 years

of top flight performance.

But the, several years ago now when I was 50 years old,

I was at the Institute for Advanced Study

and my office was right under Freeman Dyson’s office

and we were kind of friendly.

And, you know, he found out it was my 50th birthday

and said, congratulations.

And you should feel liberated because no one expects much

of a 50 year old theoretical physicist.

And he, and he obviously had felt liberated

by reaching a certain age.

And yeah, there is something to that.

I feel, you know, I feel I don’t have to catch,

I don’t have to keep in touch

with the latest hypertechnical developments

in particle physics or string theory or something.

I, because I’m not gonna, I’m really not gonna

be exploiting that.

But I, but where I am exploring in these directions

of machine learning and things like that.

And, but then, but I’m also concentrating

within physics on exploiting directions

that I’ve already established

and the laws that we already have

and doing things like,

I’m very actively involved in trying to design,

helping people, experimentalists and engineers even

to design antennas that are capable of detecting axions.

So there, and that’s, there we’re deep

in the exploitation stage.

It’s not a matter of finding the new laws,

but of really, you know, using the laws we have

to kind of finish the story off.

So it’s complicated, but I’m, you know,

I’m very happy with my life right now

and I’m enjoying it and I don’t wanna cloud that

by thinking too much that it’s gonna come to an end.

You know, it’s a gift I didn’t earn.

Is there a good thing to say about

why this gift that you’ve gotten

and didn’t deserve is so damn enjoyable?

So like, what’s the meaning of this thing, of life?

To me, interacting with people I love, my family,

and I have a very wide circle of friends now

and I’m trying to produce some institutions

that will survive me as well as my work

and it’s just, it’s, how should I say?

It’s a positive feedback loop when you do something

and people appreciate it and then you wanna do more

and you get rewarded and it’s just, how should I say?

This is another gift that I didn’t earn

and don’t understand, but I have a dopamine system

and yeah, I’m happy to use it.

It seems to get energized by the creative process,

by the process of exploration.

Very much so.

And all of that started from the little fluctuations

shortly after the Big Bang.

Frank, well, whatever those initial conditions

and fluctuations did that created you, I’m glad they did.

This is, thank you for all the work you’ve done,

for the many people you’ve inspired,

for the many, of the billion, most of your ideas

were pretty useless of the several billions,

as it is for all humans, but you had quite a few

truly special ideas and thank you for bringing those

to the world and thank you for wasting your valuable time

with me today, it’s truly an honor.

It’s been a joy and I hope people enjoy it

and I think the kind of mind expansion that I’ve enjoyed

by interacting with physical reality at this deep level,

I think can be conveyed to and enjoyed by many, many people

and that’s one of my missions in life, to share it.


Thanks for listening to this conversation

with Frank Wilczek and thank you to The Information,

NatSuite, ExpressVPN, Blinkist and 8sleep.

Check them out in the description to support this podcast

and now let me leave you with some words

from Albert Einstein, nothing happens until something moves.

Thanks for listening and hope to see you next time.

comments powered by Disqus