The following is a conversation with Barry Barish, a theoretical physicist at Caltech
and the winner of the Nobel Prize in Physics for his contributions to the LIGO detector
and the observation of gravitational waves. LIGO, or the Laser Interferometer Gravitational
Wave Observatory, is probably the most precise measurement device ever built by humans.
It consists of two detectors with four kilometer long vacuum chambers situated three thousand
kilometers apart operating in unison to measure a motion that is 10,000 times smaller than the
width of a proton. It is the smallest measurement ever attempted by science, a measurement of
gravitational waves caused by the most violent and cataclysmic events in the universe,
occurring over tens of millions of light years away. To support this podcast, please check out
our sponsors in the description. This is the Lex Friedman podcast and here is my conversation
with Barry Barish. You've mentioned that you were always curious about the physical world
and that an early question you remember stood out where you asked your dad,
why does ice float on water? And he couldn't answer. And this was very surprising to you.
So, you went on to learn why. Maybe you can speak to what are some early questions in math
and physics that really sparked your curiosity? Yeah, that memory is kind of something I used
to illustrate, something I think that's common in science is that people that do science somehow
have maintained something that kids always have. A small kid, eight years old or so,
asks you so many questions usually, typically that you consider them pests, you tell them to
stop asking so many questions. And somehow our system manages to kill that in most people.
So, in school we make people do study and do their things, but not to pester them by asking too many
questions. And I think not just myself, but I think it's typical of scientists like myself that
have somehow escaped that. Maybe we're still children or maybe we somehow didn't get it
beaten out of us, but I teach it in college level and it's, to me, one of the biggest deficits is
the lack of curiosity, if you want, that we've beaten out of them because I think it's an innate
human quality. Is there some advice or insights you can give to how to keep that flame of curiosity?
I think it's a problem of both parents and the parents should realize that's a great quality we
have, that you're curious and that's good. Instead, we have expressions like curiosity killed the cat
and more, but basically it's not thought to be a good thing. Curiosity killed the cat
means if you're too curious, you get in trouble. I don't like cats anyway, so maybe it's a good
thing. Yeah, that, to me, needs to be solved really in education and in homes. It's a realization
that there's certain human qualities that we should try to build on and not destroy one of
them is curiosity. Anyway, back to me in curiosity, I was a pest and asked a lot of questions. My
father generally could answer them at that age. And the first one I remember that he couldn't answer
was not a very original question, but basically that ice is made out of water. And so why does it
float on water? And he couldn't answer it. And it may not have been the first question. It's the
first one that I remember. And that was the first time that I realized that to learn and answer your
own curiosity or questions, there's various mechanisms. In this case, it was going to the
librarian or asking people who know more and so forth, but eventually you do it by what we call
research. But it's driven by if you're, hopefully you ask good questions. If you ask good questions
and you have the mechanisms to solve them, then you do what I do in life basically, not necessarily
physics, but, and it's a great quality in humans and we should nurture it.
Do you remember any other kind of in high school, maybe early college, more basic physics ideas
that sparked your curiosity or mathematics or science? I wasn't really into science
until I got to college, to be honest with you. But just staying with water for a minute,
I remembered that I was curious why what happens to water, you know, it rains and there's water in
a wet pavement and then the pavement dries out. What happened to this water that came down?
And I, you know, I didn't know that much. And then eventually I learned in chemistry or something
and water is made out of hydrogen and oxygen. Those are both gases. So how the heck does it make
this substances liquid? Yeah, but so that has to do with states of matter. You've, I know,
perhaps LIGO and the thing for which you've gotten the Nobel Prize and the things much of
your life work, perhaps was a happy accident in some sense in the early days. But is there a moment
where you looked up to the stars and also the same way you wondered about water,
wondered about some of the things that are out there in the universe?
Oh yeah, I think everybody's looks and is in awe and is curious about what it is out there. And,
you know, and as I learned more, I learned, of course, that we don't know very much
about what's there. And the more we learn, the more we know we don't know. I mean, we don't know
what the majority of anything is out there. It's all what we call dark matter or dark energy.
That's one of the big questions. When I was a student, those weren't questions. So we even
know less in a sense the more we look. So of course, I think that's one of the areas that
almost it's universal. People see the sky, they see the stars and they're beautiful and
see it looks different on different nights. And it's a curiosity that we all have.
What are some questions about the universe that in the same way that you felt about the ice,
that today you mentioned to me offline, you're teaching a course on the frontiers of science,
frontiers of physics. What are some questions outside the ones we'll probably talk about that kind
of, yeah, fill you with, get your flame of curiosity up and firing up, fill you with all.
Well, first, I'm a physicist, not an astronomer. So I'm interested in the physical phenomenon,
really. So the question of dark matter and dark energy, which we probably won't talk about
are recent, they're in the last 20, 30 years, certainly dark energy. Dark energy is a complete
puzzle. It goes against what you will ask me about, which is general relativity and Einstein's
general relativity. It basically takes something that he thought was what he called a constant,
which isn't. And if that's even the right theory, and it represents most of the universe. And then
we have something called dark matter. And there's good reason to believe it might be an exotic form
of particles. And that is something I've always worked on, on particle accelerators and so forth.
And it's a big puzzle what it is. It's a bit of a cottage industry in that there's lots and lots
of searches. But it may be a little bit like, you know, looking for a treasure under rocks or
something, you know, it's hard to, we don't have really good guidance, except that we have very,
very good information that is pervasive and it's there. And that it's probably particles, small,
that the evidence is all of those things. But then the most logical solution doesn't seem to work,
something called supersymmetry. And do you think the answer could be something very complicated?
You know, I like to hope that think that most things that appear complicated are actually
simple, if you really understand them. I think we just don't know at the present time, and it
isn't something that affects us. It does affect, it affects how the stars go around each other and
so forth, because we detect that there's missing gravity. But, but it doesn't affect every day
life at all. I tend to think and expect maybe, and that the answers will be simple. We just
haven't found it yet. Do you think those answers might change the way we see other sources of
gravity, black holes, the way we see the parts of the universe that we do study?
It's conceivable. The black holes that we've found in our experiment, and we're trying now to
understand the origin of those. It's conceivable, but not, doesn't seem the most likely that they're
primordial. That is, they were made at the beginning. And they, in that sense, they could
represent at least part of the dark matter. So there can be connections. Dark black holes are
a, how many there are, how much of the mass they encompass is still pretty primitive,
we don't know. So before I talk to you more about black holes, let me take a step back to,
I was actually, went to high school in Chicago and would go to take classes at Fermilab,
watch the buffalo and so on. Yeah. So let me ask about, you mentioned that Enrico for me
was somebody who was inspiring to you in a certain kind of way. Why is that? Can you speak to that?
Sure. He was amazing, actually. He's the last, this is not the, I'll come to the reason in a
minute, but the, he had a big influence on me at a young age. He, but he was the last
physicist of note that was both an experimental physicist and a theorist at the same time.
And he did two amazing things within months in 1933. He, it was, we didn't really know what the
nucleus was, what radioactive decay was, what beta decay was when electrons come out of a nucleus.
And in near, near the end of 1933, he, the neutron had just been discovered. And that meant
that we knew a little bit more about what the nucleus is, that it's made out of neutrons and
protons. The neutron wasn't discovered till 1932. And then once we discovered that there was a
neutron and proton and they made the nucleus and then their electrons that go around, the basic
the basic ingredients were there. And he wrote down not only just the theory, a theory, but a
theory that lasted decades and has only been improved on of beta decay. That is the radiation.
He did this, came out of nowhere. And it was a fantastic theory. He submitted it to Nature Magazine,
which was the primary play, best place to publish even then. And it got rejected as being too
speculative. And so he went back to his drawing board in Rome, where he was, added some to it,
made it even longer, because it's really a classic article and then published it in the local Italian
journal for physics and the German one. At the same time, in 19 January of 1932,
Giulio and Curie for the first time saw artificial radioactivity. This was an important discovery
because radioactivity had been discovered much earlier. You know, they had x-rays and you shouldn't
be using them, but they there was radioactivity. People knew it was useful for medicine.
But radioactive materials are hard to find, and so it wasn't prevalent. But if you could make them,
then they had great use. And Giulio and Curie were able to bombard aluminum or something
with alpha particles and find that they excited something that decayed and had some half-life
and so forth, meaning it was artificial version, or let's call it not a natural version, an induced
version of radioactive materials. And Fermi somehow had the insight, and I still can't see where he
got it, that the right way to follow that up was not using charged particles like alphas and so
forth, but use these newly discovered neutrons as the bombarding particle. It seemed impossible.
They barely had been seen. It was hard to get very many of them, but it had the advantage that they
are not charged, so they go right into the nucleus. And that turned out to be the experimental work
that he did that won him the Nobel Prize, and it was the first step in fission, discovery of fission.
He did two completely different things, an experiment that was a great idea and a tremendous
implementation, because how do you get enough neutrons? And then he learned quickly that not
only do you want neutrons, but you want really slow ones. He learned that experimentally, and he
learned how to make slow ones, and then they were able to go through the periodic table and make
lots of particles. He missed on fission at the moment, but he had the basic information,
and then fission followed soon after that. Forgive me for not knowing, but is the birth
of the idea of bombarding with neutrons, is that an experimental idea? Was it born out of
experiment? He just observed something, or is this an Einstein-style idea where you
come up from basic intuition? I think it took a combination, because he realized that neutrons
had a characteristic that would allow them to go all the way into the nucleus when we didn't really
understand what the structure was of all this. So that took an understanding or recognition
of the physics itself of how a neutron interacts compared to, say, an alpha particle that Julio
and Curie had used. And then he had to invent a way to have enough neutrons, and he had a team
of associates, and he pulled it off quite quickly. So it was pretty astounding.
And probably, maybe you can speak to it, his ability to put together the engineering aspects
of great experiments and doing the theory. They probably fed each other. I wonder,
can you speak to why we don't see more of that? Is that just really difficult to do?
It's difficult to do. Yeah, I think in both theory and experiment in physics anyway,
was it was conceivable if you had the right person to do it, and no one's been able to do
it since. So I had the dream that that was what I was going to be like for me.
So you love both sides of it, the theory. Yeah, I never liked the idea that you did
experiments without really understanding the theory, or the theory should be related very
closely to experiments. And so I've always done experimental work that was closely related
to the theoretical ideas. I think I told you I'm Russian, so I'm going to ask some romantic
questions. But is it tragic to you that he's seen as the architect of the nuclear age,
that some of his creations led to potentially, some of his work has led to potentially still
the destruction of the human species, some of the most destructive weapons?
I think even more general than him, I gave you all the virtues of curiosity a few minutes ago.
There's an interesting book called The Ratchet of Curiosity,
you know, a ratchet is something that goes in one direction. And that is written by a guy
who's probably a sociologist or philosopher or something. And he picks on this particular
problem but other ones. And that is the danger of knowledge, basically. You're curious,
you learn something. So it's a little bit like curiosity killed the cat. You have to be worried
about whether you can handle new information that you get. So in this case, the new information had
to do with really understanding nuclear physics. And that information, maybe we didn't have the
sophistication to know how to keep it under control. And Fermi himself was a very apolitical person.
So he wasn't very driven by or at least he appears in all of his writing, the writing of his wife,
the interactions that others had with him as either he avoided it all or he was pretty apolitical.
I mean, he just saw the world through kind of the lens of a scientist. But he asked if it's
tragic that the bomb was tragic, certainly on Japan. And he had a role in that. So I wouldn't
want it as my legacy, for example. I mean, but brought it to the human species that
that it's the ratchet of curiosity that we
we do stuff just to see what happens that that curiosity that in sort of my area of artificial
intelligence, that's been a concern there on a small scale on a silly scale, perhaps currently,
there's constantly unintended consequences, the equator system. And you put out there and you have
intuitions about how it will work. You have hopes how it will work, but you put it out there just
to see what happens. And in most cases, because artificial intelligence is currently not super
powerful, it doesn't create large scale negative effects. But that same curiosity as it progresses
might lead to something that destroys the human species. And the same may be true for bioengineering.
There's people that, you know, engineer viruses to protect us from viruses, to see, you know,
how do how close is this to mutating so it can jump to humans, or going, you know, or engineering
defenses against those. And it seems exciting in the application, the positive applications
are really exciting at this time. But we don't think about how that runs away in decades to come.
Yeah. And I think it's the same idea as this little book, The Ratchet of Science, the
Ratchet of Curiosity. I mean, whether you pursue, take curiosity and let artificial
intelligence or machine learning run away with having its solutions to whatever you want,
or we do it, is I think a similar consequence. I think from what I've read about Enrico Fermi,
he became a little bit cynical about the human species towards the end of his life,
both having observed what he observed. We didn't write much. I mean, he died young,
he died soon after the World War. There was already, you know, the work by Teller to develop
the hydrogen bomb. And I think he was a little cynical of that, you know, pushing it even further
and rising tensions between the Soviet Union and the U.S. and look like an endless thing.
So, but he didn't say very much, but a little bit, as you said that.
Yeah, there's a few clips to sort of maybe picked on a bad mood, but in a sense that almost like
a sadness, a melancholy sadness to a hope that waned a little bit about that perhaps we can do,
like this curious species can find the way out.
Well, especially I think people who worked like he did at Los Alamos and spent years of their life
somehow had to convince themselves that dropping these bombs would bring lasting peace.
And it did.
And that it didn't, yeah.
As a small, interesting aside, it'd be interesting to hear if you have opinions on this.
His name is also attached to the Fermi Paradox, which asks if there's a, you know,
with, for me, it's a very interesting question, which is if it does seem, if you sort of reason,
basically, that there should be a lot of alien civilizations out there. If the human species,
if Earth is not that unique by basic, no matter the values you pick,
it's likely that there's a lot of alien civilizations out there. And if that's the case,
why have they not at least obviously visited us or sent us loud signals that everybody can hear?
Fermi's quoted as saying, sitting down at lunch, I think it was with
Teller and Herb York, who was kind of the one of the fathers of the atomic bomb.
And he sat down and he says something like, where are they?
Which meant, where are these other? And then he did some numerology where he
calculated, you know, how many, what they knew about how many galaxies there are and how many
stars and how many planets then are like the Earth and blah, blah, blah. That's been done much
better by somebody named Drake. And so people usually refer to the, I don't know whether it's
called the Drake formula or something, but it has the same conclusion. The conclusion is it would
be a miracle if there weren't other, you know, there's the statistics are so high that how can
we be singular and separate? That's so probably there is, but there's almost certainly life
somewhere. Maybe there was even life on Mars a while back, but intelligent life,
probably why are we so, so, you know, the statistics say that communicating with us,
I think that it's harder than people think. We might not know the right way to expect the
communication. But all the communication that we know about travels at the speed of light.
And we don't, we don't think anything can go faster in the speed of light. That
limits the problem quite a bit. And it makes it difficult to have any back and forth communication.
You can send signals like we try to or look for, but to have any communication, it's pretty hard
when you, it has to be close enough that the speed of light would mean we could communicate
with each other. And I think, and we didn't even understand that. I mean, we're in advanced
civilization, but we didn't even understand that a little more than 100 years ago. So are we
just not advanced enough, maybe, to know something about that's the speed of light. Maybe there's
some other way to communicate that isn't based on electromagnetism. I don't, I don't know.
Now, gravity seems to be also this have the same speed that was a principle that Einstein had and
something we've measured actually. So is it possible? I mean, so we'll talk about gravitational
waves. And it in some sense, there's a there's a brainstorming going on, which is like,
how do we detect the signal? Like, what would a signal look like? And how would we detect it?
And that's true for gravitational waves. That's true for basically any physics phenomena.
You have to predict that that signal should exist. You have to have some kind of theory
and model why that signal should exist. I mean, is it possible that aliens are communicating
with us via gravity? Like, why not? Well, yeah, it's true. Why not? For us, it's very hard to
detect these gravitational effects. They have to come from something pretty that has a lot of
gravity like black holes. But we're pretty primitive at this stage. There's very reputable
physicists that look for a fifth force, one that we haven't found yet. Maybe it's the key. So,
you know, it's what would that look like? What would a fifth force of physics look like exactly?
Well, usually they think it's probably a long range for longer range force than we have now.
But they're reputable for the colleagues of mine that spend their life looking for a fifth force.
So, longer range than gravity? Yeah.
Yeah. It doesn't fall off like one over r squared, but maybe separately. Gravity Newton
taught us goes like inversely, one over the square of the distance apart you are. So,
it falls pretty fast. That's okay. So, now we have a theory of what consciousness is. It's just the
fifth force of physics. Yeah. There we go. That's a good hypothesis. Speaking of gravity,
what are gravitational waves? Let's maybe start from the basics.
We learned gravity from Newton, right? You and you were young. You were told that if you jumped
up, the earth pulls you down. And when the apple falls out of the tree, the earth pulls it down.
And maybe you even asked your teacher why. But most of us accepted that. That was Newton's
picture, the apple falling out of the tree. But Newton's theory never told you why the
apple was attracted to the earth. That was a missing in Newton's theory. Newton's theory also,
so Newton recognized at least one of the two problems I'll tell you. One of them is,
there's more than those, but one is why does the earth, what's the mechanism by which
the earth pulls the apple or holds the moon when it goes around, whatever it is.
That's not explained by Newton. Even though he has the most successful theory of physics ever,
went 200 and some years with nobody ever seeing a violation. But he accurately describes the
movement of an object falling down to earth, but he's not answering why that, because it's a distance.
He gives a formula, which it's a product of the earth's mass, the apple's mass, inversely proportional
to the square, the distance between. And then the strength he called capital G, the strength he
couldn't determine, but it was determined 100 years later. But no one ever saw a violation of
this until a possible violation, which Einstein fixed, which was very small that has to do with
Mercury going around the sun, the orbit being slightly wrong, if you calculate it by Newton's
theory. But like most theories then in physics, you can have a wonderful one like Newton's theory.
It isn't wrong, but you have to have an improvement on it to answer things that
it can't answer. And in this case, Einstein's theory is the next step. We don't know if it's
anything like a final theory or even the only way to formulate it either. But he formulated this
theory, which he released in 1915. He took 10 years to develop, but even though in 1905 he solved
three or four of the most important problems in physics in a matter of months, and then he spent 10
years on this problem before he let it out. And this is called general relativity. It's a new theory
of gravity. 1915 and 1916, Einstein wrote a little paper where he did not do some fancy derivation.
Instead, he did, what I would call it, used his intuition, which he was very good at too.
And that is he noticed that if he wrote the formulas for general relativity in a particular way,
they looked a lot like the formulas for electricity and magnetism.
Being Einstein, he then took the leap that electricity and magnetism, we discovered only 20
years before that in the 1880s, have waves. Of course, that's light and electromagnetic
rays, radio waves, everything else. So he said if the formulas look similar, then gravity probably
has waves too. That's such a big leap, by the way. I mean, maybe you can correct me, but that just
seems like a heck of a leap. Yeah. And it was considered to be a heck of a leap.
So first, that paper was, except for this intuition, was poorly written, had a serious
mistake. It had a factor of two wrong in the strength of gravity, which meant if we use those
formulas, we would. And two years later, he wrote a second paper. And in that paper, it turns out
to be important for us, because in that paper, he not only fixed his factor of two mistake,
which he never admitted, he just fixed it like he always did. And then he told us how you make
gravitational waves, what makes gravitational waves. And you might recall in electromagnetism,
we make electromagnetic waves in a simple way. You take a plus charge and minus charge,
you oscillate like this, and that makes an electromagnetic waves. And a physicist named
Hertz made a receiver that could detect the waves and put it in the next room. He saw them and
moved forward and backward and saw that it was wave-like. So Einstein said it won't be a dipole
like that. It'll be a four-pole thing. And that's what it's called a quadrupole moment that gives
the gravitational waves. So he saw that again by insight, not by derivation. That's at the table
for which he needed to do it. At the same time, in the same year, Schwarzschild, not Einstein,
said there were things called black holes. So it's interesting that that came the same.
So what year was that? 1915. It was in parallel. I should probably know this, but did Einstein not
have any intuition that there should be such things as black holes? That came from Schwarzschild.
Oh, interesting. Yeah. So Schwarzschild, who was a German theoretical physicist, he got killed
in the war, I think, in the First World War, two years later or so. He's the one that proposed
black holes, that there were black holes. It feels like a natural conclusion of general
relativity, no? Or is that not? Well, it may seem like it, but I don't know about a natural
conclusion. It's a result of curved space-time, though. Right. But it's such a weird result
that you might have to, it's a special case. Yeah, it's a special case. Yeah. So I don't know.
Anyway, Einstein then, an interesting part of the story is that Einstein then left the problem.
Most physicists, because it really wasn't derived, he just made this, didn't pick up on it, or
general relativity much, because quantum mechanics became the thing in physics. And
Einstein only picked up this problem again after he immigrated to the US. So he came to the US in
1932. And I think in 1934 or five, he was working with another physicist called Rosen, who he did
several important works with, and they revisited the question. And they had a problem that most
of us as students always had that studied general relativity. General relativity is really hard
because it's four-dimensional instead of three-dimensional. And if you don't set it up right,
you get infinities, which don't belong there. We call them coordinate singularities as a name.
But if you get these infinities, you don't get the answers you want. And he was trying to derive
now general relativity from general relativity, gravitational waves. And in doing it, he kept
getting these infinities. And so he wrote a paper with Rosen that he submitted to our most important
journal, Physical Review Letters. And that when it was submitted to Physical Review Letters,
it was entitled, Do Gravitational Waves Exist? A very funny title to write 20 years after he proposed
they exist. But it's because he had found these singularities, these infinities. And so the
editor at that time, and part of it that I don't know, is peer review. We live and die by peer
review as scientists, send our stuff out. And we don't know when peer review actually started,
or what peer review Einstein ever experienced before this time. But the editor of Physical
Review sent this out for review. He had a choice. He could take any article and just accept it. He
could reject it, or he could send it for review. Right. I believe the editors used to have much
more power. Yeah, yeah. And he was a young man. His name was Tate. And he ended up being editor for
years. But so he sent this for review to a theoretical physicist named Robertson, who was
also in this field of general relativity, who happened to be on sabbatical at that moment at
Caltech. Otherwise, his institution was Princeton, where Einstein was. And he saw that the way they
set up the problem, the infinities were like I might get as a student, because if you don't set
it up right in general relativity, you get these infinities. And so he reviewed the article and
told, gave an illustration that if they set it up in what are called cylindrical coordinates,
these infinities went away. The editor of Physical Review was obviously intimidated by
Einstein. He wrote this really not a letter back like I would get saying, you're screwed up in your
paper. Instead, it was kind of, what do you think of the comments of our referee? Einstein wrote back.
It's a well documented letter, wrote back a letter to Physical Review saying, I didn't send you the
paper to send it to one of your so-called experts. I sent it to you to publish. I now, I withdraw the
paper. And he never published again in that journal. That was 1936. Instead, he rewrote it
with the fixes that were made, changed the title, and published it in what was called the Franklin
Review, which is the Franklin Institute in Philadelphia, which is Benjamin Franklin Institute,
which doesn't have a journal now, but did at that time. So the article is published. It's the last
time he ever wrote about it. It remained controversial. So it wasn't until close to 1960, 1958,
where there was a conference that brought together the experts in general relativity
to try to sort out whether there was, whether it was true that there were gravitational waves
or not. And there was a very nice derivation by a British theorist from the heart of the theory
that gets gravitational waves. And that was number one. The second thing that happened at that meeting
is Richard Feynman was there. And Feynman said, well, if there's typical Feynman, if there's
gravitational waves, they need to be able to do something. Otherwise, they don't exist. So they
have to be able to transfer energy. So he made an idea of a Gadankan experiment that is just a
bar with a couple of rings on it. And then if a gravitational wave goes through, it distorts the
bar. And that creates friction on these little rings. And that's heat and that's energy. So that
that meant- Is that a good idea? That sounds like a good idea. Yeah. It means that he showed that
with the distortion of space-time, you could transfer energy just by this little idea. And
it was shown theoretically. So at that point, it was believed theoretically then by people that
gravitational waves should exist. No, we should be able to detect them. We should be able to
detect them except that they're very, very small. And so what kind of- There's a bunch of questions
here, but what kind of events would generate gravitational waves? You have to have this,
what I call quadrupole moment. That comes about if I have, for example, two objects that go around
each other like this, like the earth around the sun or the moon around the earth. Or in our case,
it turns out to be two black holes going around each other like this. So how's that different
than basic oscillation back and forth? Is it just more common in nature to have-
Oscillation is a dipole moment. So it has to be in three-dimensional space kind of oscillation.
So you have to have something that's three-dimensional that'll give what's what I
called a quadrupole moment. That's just built into this. And luckily in nature, you have stuff out.
And luckily things exist. And it is luckily because the effect is so small that you could say,
look, I can take a barbell and spin it, and detect the gravitational waves. But unfortunately,
no matter how fast I spin it, so I know how to make gravitational waves, but they're so weak,
I can't detect them. So we have to take something that's stronger than I can make. Otherwise,
we would do what Hertz did for electromagnetic waves, go in our lab, take a barbell, put it on
something, spin it. Can I ask a dumb question? So a single object that's weirdly shaped, does
that generate gravitational waves? So if it's rotating? Sure. But it's just much weaker signal.
It's weaker. Well, we didn't know what the strongest signal would be that we would see.
We targeted seeing something called neutron stars, actually, because black holes,
we don't know very much about. It turned out we were a little bit lucky there was a stronger source,
which was the black holes. Well, another ridiculous question. So
you say waves. What does a wave mean? The most ridiculous version of that question is,
what does it feel like to ride a wave as you get closer to the source? Or experience it?
Well, if you experience a wave, imagine that this is what happens to you. I don't know what you mean
about getting close. It comes to you. So it's like this light wave or something that comes
through you. So when the light hits you, it makes your eyes detected. I flashed it. What does this
do? It's like going to the amusement park and they have these mirrors. You look in this mirror
and you look short and fat. The one next to you makes you tall and thin. Imagine that you went
back and forth between those two mirrors once a second. That would be a gravitational wave with
a period of once a second. If you did it 60 times a second, go back and forth. Then that's all that
happens. It makes you taller and shorter and fatter back and forth as it goes through you
at the frequency of the gravitational wave. So the frequencies that we detect are higher
than one a second, but that's the idea. And the amount is small. Amount is small. But if you're
closer to the source of the wave, is it the same amount? Yeah, it doesn't dissipate. It doesn't
dissipate. Okay, so it's not that fun of an amusement ride. Well, it does dissipate,
but it's proportional to the distance. It's not a big power. Gotcha. But it would be a fun ride
if you get a little bit closer or a lot closer. I wonder what the, this is a ridiculous question,
but I have you here. Like the getting fatter and taller. I mean, that experience, for some reason,
that's mind blowing to me because it brings the distortion of spacetime to you. I mean,
spacetime is being morphed. Right? This is a wave. That's so weird. And we're in space.
Yeah, we're in space and now it's moving. I don't know what to do with it. I mean, does it, okay.
How much do you think about the philosophical implications of general relativity? Like that
we're in spacetime and it can be bent by gravity? Like, is that just what it is? Are we supposed
to be okay with this? Because like Newton, even Newton is all weird, right? But that at least
like makes sense. That's our physical world. You know, when an apple falls, it makes sense.
But like the fact that entirety of the spacetime we're in can bend.
Well, that's really mind blowing. Let me make another analogy. This is a therapy session for me
at this point. Yeah, right. Another analogy. Thank you. So imagine you have a trampoline.
Yes. Okay. What happens if you put a marble on a trampoline? Doesn't do anything, right?
No. Maybe a little bit, but not much. Yeah. I mean, just if I drop it, it's not going to go
anywhere. Now imagine I put a bowling ball at the center of the trampoline.
Now I come up to the trampoline and put a marble on. What happens?
You know, roll towards the bowling ball. All right. So what's happened is the presence of this
massive object distorted the space that the trampoline did. This is the same thing that happens to
the presence of the earth, the earth and the apple, the presence of the earth affects the space
around it just like the bowling ball on the trampoline. Yeah. This doesn't make me feel better.
I'm referring from the perspective of an ant walking around on that trampoline,
then some guy just dropped a ball and not only dropped a ball, right? It's not just dropping
a bowling ball. It's making the ball go up and down or doing some kind of oscillation thing
where it's like waves. And that's so fundamentally different from the experience on being on flat
land and walking around and just finding delicious sweet things as ant does. It just feels like to
me from a human experience perspective, completely, it's humbling. It's truly humbling. It's humbling,
but we see that kind of phenomenon all the time. Let me give you another example. Imagine that you
walk up to a still pond. Yes. Okay. Now I throw a rock in it. What happens? The rock goes in,
sinks to the bottom, fine. And these little ripples go out and they travel out. That's exactly what
happens. I mean, there's a disturbance, which is these safe, the bowling ball or our black holes.
And then the ripples, they go out in the water. They don't have the rock, any part, pieces of the
rock. The thing is, I guess, what's not disturbing about that is it's a flat two-dimensional surface
that's being disturbed. For a three-dimensional surface, three-dimensional space to be disturbed
feels weird. It's even worse. It's four-dimensional because it's space and time. So that's why you
need Einstein is to make it four-dimensionally. To make it four-dimensional. Yeah. To take the
same phenomenon and look at it in all of space and time. Anyway, luckily for you and I and all of us,
the amount of distortion is incredibly small. So it turns out that if you think of space itself,
now this is going to blow your mind too. If you think of space as being like a material,
like this table, it's very stiff. We have materials that are very pliable, materials that are very
stiff. So space itself is very stiff. So when gravitational waves come through it, luckily
for us, it doesn't distort it so much that it affects our ordinary life very much.
No, I mean, that's great. That's great. I thought there was something bad coming. No,
this is great. No, not bad. That's great news. So I mean, that, I mean, perhaps we evolved
as a life on earth to be such that for us, this particular set of effects of gravitational waves
is not that significant, maybe. Maybe that's why. You probably used this effect today
or yesterday. What? So it's pervasive. Well, you mean gravity or the way, or external,
because I only... Curvature of space. Curvature of space. How? I only care
personally as a human, right? The gravity of earth. But you use it every day almost.
Oh, it's curving. No, no, no. It's in this thing. Every time it tells you where you are,
how does it tell you where you are? It tells you where you are because we have 24 satellites or
some number that are going around in space and it asks how long it takes being to go to the
satellite and come back the signal to different ones and then it triangulates and tells you where
you are. And then if you go down the road, it tells you where you are. Do you know that if you did
that with the satellites and you didn't use Einstein's equations? Oh, no. You won't get the
right answer. That's right. And in fact, if you take a road that's, say, 10 meters wide, I've done
these numbers and you ask how long you'd stay on the road if you didn't make the correction
for general relativity, this thing you're poo-pooing, because you're using every day,
you'd go off the road. You'd go off the road. Well, actually, that might be my problem. So you use it,
so poo-poo it. Well, I think I'm using an Android, so maybe... And the GPS doesn't work, though,
also. Maybe I'm using Newton's physics, so I need to upgrade to general relativity.
So the gravitational waves in Einstein had... Wait, Feynman really does have a part in the story.
Was that one of the first kind of experimental proposed... Well, he did what we call a Godonkin
experiment. That's a thought experiment. Okay, not a real experiment. But then after that,
then people believe gravitational waves must exist. You can kind of calculate how big they are. There's
tiny. And so people started searching. The first idea that was used was Feynman's idea.
And they... Oh, very end of it. And it was to take a great big, huge bar of aluminum
and then put around... And it's made like a cylinder. And then put around it some very,
very sensitive detectors so that if a gravitational wave happened to go through it, it would go...
And you detect this extra strain that was there. And that was this method that was used until we
came along. It wasn't a very good method to use. And what was the... So we're talking about a pretty
weak signal here. Yeah, that's why that method didn't work. So what... Can you tell the story
of figuring out what kind of method would be able to detect this very weak signal of gravitational
waves? So remembering the... Remembering what happens when you go to the amusement park.
That it's going to do something like stretch this way and squash that way, squash this way,
and stretch this way. We do have an instrument that can detect that kind of thing. It's called
an interferometer. And what it does is it just basically takes usually light. And the two directions
that we're talking about, you send light down one direction and the perpendicular direction. And if
nothing changes, it takes the same... And the arms are the same length. It just goes down,
bounces back. And if you invert one compared to the other, they cancel. So there's nothing
happens. But if it's like the amusement park and one of the arms got shorter and fatter,
so it took longer to go horizontally than it did to go vertically, then when the light comes back,
that comes back somewhat out of time. And that basically is the scheme. The only problem is
that that's not done very accurately in general. And we had to do it extremely accurately.
So what's the difficulty of doing so accurately? Okay. So the measurement that we have to do
is a distortion in time. How big is it? It's a distortion. That's one part in 10 to the 21.
That's 21 zeros and a one. Okay. Wow. And so this is like a delay in the thing coming back?
It's one of them coming back after the other one, but the difference is just one part in 10 to the
21. So for that reason, we make it big. Let the arms be long. Okay. So one part in 10 to the 21.
In our case, it's kilometers long. So we have an instruments of kilometers in one direction,
kilometers in the other. How many kilometers? We're talking about four kilometers.
Four kilometers in each direction. If you take then one part in 10 to the 21,
we're talking about measuring something to 10 to the minus 18 meters.
Okay. Now to tell you how small that is, the proton thing we're made of,
which you can't go and grab so easily, is 10 to the minus 15 meters.
So this is one 1,000th the size of a proton. That's the size of the effect.
Einstein himself didn't think this could be measured. Have we ever seen actually he said that?
But that's because he didn't anticipate modern lasers and techniques that we developed.
Okay. So maybe can you tell me a little bit what you're referring to as LIGO,
the laser interferometer gravitationally observatory? What is LIGO?
Can you just elaborate kind of the big picture view here before I ask you specific questions
about it? Yeah. So in the same idea that I just said, we have two long vacuum
pipes, 10 to four kilometers long. Okay. We start with a laser beam and we divide the beam
beam going down the two arms and we have a mirror at the other end, reflects it back.
It's more subtle, but we bring it back. If there's no distortion in spacetime and the lengths are
exactly the same, which we calibrate them to be, then when it comes back, if we just
invert one signal compared to the other, they'll just cancel. So we see nothing.
Okay. But if one arm got a little bit longer than the other, then they don't come back at
exactly the same time. They don't exactly cancel. That's what we measure.
So to give a number to it, we have to do that to, we have the change of length to be able to do this
10 to the minus 18 meters to one part in 10 to the 12th. And that was the big experimental
challenge that required a lot of innovation to be able to do.
So you gave a lot of credit to, I think Caltech and MIT for some of the technical
developments within this project. Is there some interesting things you can speak to
at the low level of some cool stuff that had to be solved? I'm a software engineer, so
all of this, I have so much more respect for everything done here than anything I've ever
done. So it's just code. So I'll give you an example of doing
mechanical engineering at a better, at a, basically mechanical engineering and geology,
and maybe at a level. So what do we, what's the problem? The problem is the following,
that I've given you this picture of an instrument that by some magic, I can make good enough to
measure this very short distance, but then I put it down here, it won't work. And the reason it
doesn't work is that the earth itself is moving all over the place all the time. You don't realize
that it seems pretty good to you, but it's moving all the time. So somehow it's moving so much that
you, we can't deal with it. We happen to be trying to do the experiment here on earth,
but we can't deal with it. So we have to make the instrument isolated from the earth. Oh no.
At the frequencies we're at, we've got to float it. That's a mechanical, that's an
engineering problem, not a physics problem. So when you actually, like we're doing, we're
having a conversation on our podcast right now, there's, and people who record music work with
this, you know, how to create an isolated room, and they usually build a room within a room,
but that's still not isolated. In fact, they say it's impossible to truly isolate from sound,
from noise and stuff like that. But that, that's like one step of millions that you took
is building a room inside a room. You basically have to isolate all.
No, this is actually an easier problem. It's just you have to do it really well. So the
making a clean room is really a tough problem because you have to put a room inside a room.
Yeah. So this is really simple engineering or physics. Okay. So what do you have to do?
How do you isolate yourself from the, from the earth? Yes. First, we work at, we're not looking
at all frequencies for gravitational waves. We're looking at particular frequencies
that you can deal with here on earth. So what are frequencies with those be?
You were just talking about frequencies. I mean, I don't know. We know by evolution,
our bodies know, it's the audio band. Okay. The reason our ears work where they work is
that's where the earth isn't going, making too much noise. Okay. So the reason our ears work,
the way they work is because this is where it's quiet. That's right. So if you go to,
if you go to one Hertz instead of 10 Hertz, it's the earth is really moving around. So,
so somehow we live in a, what we call the audio band, it's 10s of Hertz to 1000s of Hertz. That's
where we live. That's where we live. Okay. If we're going to do an experiment on the earth.
Might as well do it. It's the same frequency. That's where the earth is quiet is. So we have
to work in that frequency. So we're not looking at all frequencies. Okay. So the solution for the
shaking of the earth to get rid of it is pretty mundane. If we do the same thing that you do
to make your car drive smoothly down the road. So what happens when your car goes over a bump?
Early cars did that. They bounced. Right. Okay. But you don't feel that in your car.
So what happened to that energy? You can't just disappear energy. So we have these things called
shock absorbers in the car. What they do is they absorb, they take the, the thing that went like
that and they basically can't get rid of the energy, but they move it to very, very low frequency.
So what you feel isn't, you feel like go smoothly. Okay. All right. So
we also work at this frequency. So if we, so we basically why, why do we have to do anything other
than shock absorbers? So we made the world's fanciest shock absorbers. Okay. Not just like in
your car where there's one layer of them, they're just the right squishiness and so forth. They're
better than what's in the cars and we have four layers of it. So whatever shakes and gets through
the first layer, we treat it in a second, third, fourth layer. So some mechanical engineering
problem. Yeah. That's what I said. So it's not, there's no weird tricks to it. Like,
like a chemistry type thing or no, no, just while the right squishiness, you know,
I need the right material inside and ours looks like little springs, but they're
springs. There's springs. So like legitimately like shock absorbers. Yeah.
What? Okay. Okay. And this is now experimental physics at the edits limit. Okay. So you do this
and we make the world's fanciest shock absorbers just mechanical engineering.
Just mechanical engineering. This is hilarious. But we didn't just, we weren't good enough to
discover gravitational waves. So, so we did another, we added another feature and it's
something else that you're aware of, probably have one. And that is to get rid of noise.
You've probably noise, which is you don't like. And that's the same principle that's in these
little Bose earphones. Noise canceling. Noise canceling. So, so how do they work? They basically,
you go on an airplane and they sense the ambient noise from the engines and cancel it because
it's just the same over and over again. They cancel it. And when the stewardess comes and asks
you whether you want coffee or a tea or a drink or something, you hear her fine because she's
not ambient. She's the signal. So. Are we talking about active canceling? Like where?
Active canceling. So. This is, okay. So another. Don't tell me you have active canceling on this.
Yeah. Besides the shock absorbers. So we had this. So inside this array of shock absorbers,
we, you asked for some interesting. This is awesome. So inside this, it's harder than the
earphone problem, but it's just engineering. We have to see measure not just that the
engines still made noise, but the earth is shaking. It's moving in some direction.
So we have to actually tell not only that there's noise and cancel it, but what direction it's from.
So we put this array of seismometers inside this array of shock absorbers and measure the
residual motion and its direction. And we put little actuators that push back against it and
cancel it. This is awesome. So you have the actuators and you have the thing that is sensing the
vibrations and then you have the actual actuators that adjust for that and do so in perfect
synchrony. Yeah. What if it all works right? And so how much do we reduce the shaking of the earth?
I mean, one part in 10 to the 12th. So what gets through us is one part in 10 to the 12th.
That's pretty big reduction. You don't need that in your car, but that's what we do. And so that's
how isolated we are from the earth. And that was the biggest, I'd say, technical problem outside
of the physics instrument, the interferometer. Can I ask you a weird question here? You make it
very poetically and humorously. You're just saying it's just a mechanical engineering problem.
But is this one of the biggest precision mechanical engineering efforts ever?
I mean, this seems exceptionally difficult. It is. And so it took a long time. And I think
nobody seems to challenge the statement that this is the most precise instrument that's ever been
built, LIGO. I wonder what listening to Led Zeppelin sounds on this thing, because it's so isolated.
I mean, this is like, I don't know. No background. No back. It's, wow. Wow. Wow. So when you were
first conceiving this, I would probably, if I was knowledgeable enough, kind of laugh off the
possibility that this is even possible. I'm sure, like, how many people believe that this is possible?
Did you believe this is possible? Oh, I did. I didn't know that we needed, for sure, that we
needed active. When we started, we did just passive, but we were doing the test to develop the active
to add as the second stage, which we ended up needing. But there was a lot of, you know, now
there was a lot of skepticism. A lot of us, especially astronomers, felt that money was being
wasted, as we were also expensive. Doing what I told you is not cheap. So it was kind of controversial.
It was funded by the National Science Foundation. Can you just link on this just for a little longer,
the actuator thing, the active canceling? Do you remember, like, little experiments that were
done along the way to prove to the team to themselves that this is even possible?
So from our, because I work with quite a bit of robots. And to me, the idea that you could do it
this precisely is humbling and embarrassing, frankly, because, like, this is another level
of precision that I can't even, because robots are a mess. And this is basically
one of the most precise robots ever. Right. So like, is there, do you have any, like, small-scale
experiments that were done that just, you know, this is possible?
Yeah. And larger scale. We made, we made tests, that also has to be in vacuum, too. But we made
test chambers that had this system in it, our first mock of this system, so we could test it.
And optimize it and make it work. But it's just a mechanical engineering problem.
Okay. And humans are just ape descendants. I got you. I got you. Is there any video of this,
like, some kind of educational purpose visualizations of this active canceling?
I don't think so. I mean, does this live on?
Well, we work, for parts of it, for the active canceling, we worked with, for the instruments,
for the sensor and instruments, we worked with a small company near where you are,
because it was RMIT people that got them that were, you know, interested in the problem because
they thought they might be able to commercialize it for making stable tables to make microelectronics,
for example, which are limited by how stable the table is. I mean, at this point, it's a little
expensive. So you never know. You never know where this leads. Okay. So maybe on the,
let me ask you just sticking it a little longer, this silly old mechanical engineering problem.
What was, to you, kind of the darkest moment of what was the hardest stumbling block to get over
on the engineer side? Like, was there any time where there was a doubt, whereas, like, I'm not
sure we would be able to do this, a kind of engineering challenge that was hit? Do you
remember anything like that? I think the one that, that my colleague at MIT, Ray Weiss,
worked on so hard and was much more of a worry than this. This is only a question. If you'd not
do it well enough, you have to keep making it better somehow. But this whole huge instrument
has to be in vacuum. And the vacuum tanks are, you know, this big around. And so it's the world's
biggest high vacuum system. And how do you make it, first of all? How do you make this four meter
long sealed vacuum system? It has to be made out of four kilometers long. Four kilometers long,
would I say something else? Meters. For four kilometers long. Big difference. Yeah. And so,
but to make it, yeah, we started with a roll of stainless steel. And then we roll it out like a
spiral so that there's a spiral weld on it. Okay, so the engineering was fine. We did that. We
worked through very good companies and so forth to build it. But the big worry, it was, what if you
develop a leak? This is a high vacuum, not just vacuum system. Typically in a laboratory, if there's
a leak, you put helium around the thing you have. And then you detect where the helium is coming in.
But if you have something as big as this, you can't surround it with helium. So you might not
actually even know that there's a leak and it will be affecting? Well, we have, we can measure the
how good the vacuum is. So we can know that, but there are leak and develop and then we don't,
how do we fix it? Or how do we find it? And so that was, you asked about a worry. That was always
a really big worry. What's the difference in a high vacuum and a vacuum? What is high vacuum?
That's like some, a delta of close to vacuum. Is there some threshold? Well, there's a unit.
High vacuum is when the vacuum and the units that are used, which are TOR, so it's 10 to the minus
none. And there's high vacuum is usually used in small places. The biggest vacuum system
period is that CERN in this big particle accelerator, but the high vacuum where they
need really good vacuum so particles don't scatter and it is smaller than ours. So ours is a really
large high vacuum system. I don't know. This is so cool. I mean, this is basically by far the
greatest listening device ever built by human. The fact that like descendants of apes could do this,
that evolution started with single cell organisms. I mean, is there any more? I'm a huge
theory is like, yeah, yeah. But like bridges, when I look at bridges from a civil engineering
perspective is one of the most beautiful creations by human beings. It's physics.
You're using physics to construct objects that can support huge amount of mass.
And it's like structural, but it's also beautiful and that humans can collaborate to create that
throughout history. And then you take this on another level. This is exciting to me beyond
measure that humans can create something so precise. But another concept lost in this,
you just said you started talking about single cell. Yeah. Okay. You have to realize this
discovery that we made that everybody's bought off on happened 1.3 billion years ago,
somewhere. And then the signal came to us 1.3 billion years ago, we were just converting
on the earth from single cell to multi cell life. So when this actually happened, this collision
of two black holes, we weren't here. We weren't even close to being here. We're both developing
slowly. Yeah, we were going from single cell to multi cell life at that point.
All to meet up at this point. Yeah. Wow, that's like, that's almost romantic.
It is. Okay. So on the human side of things, it's kind of fascinating because you're talking
about over a thousand people team for LIGO. Yeah. They started out with around 100.
For parts of the time at least led this team. What does it take to lead a team like this
of incredibly brilliant theoreticians and engineers and just a lot of different parties
involved, a lot of egos, a lot of ideas. You had this funny example, I forget where,
where in publishing a paper, you have to all agree on the phrasing of a certain sentence
or the title of the paper and so on. That's a very interesting, simple example. I'd love you
to speak to that, but just in general, what does it take to lead this kind of team?
Okay. I think the general idea is one we all know. You want to get where the
sum of something is more than the individual parts is what we say, right?
So that's what you're trying to achieve. Yes. Okay. How do you do that actually?
Mostly if we take multiple objects or people, I mean, you put them together, the sum is less.
Yes. Why? Because they overlap. So you don't have individual things that, you know, this person
does that, this person does that, then you get exactly the sum. But what you want is to develop
where you get more than what the individual contributions are. We know that's very common.
People use that expression everywhere. And it's the expression that has to be kind of
built into how people feel it's working. Because if you're part of a team and you realize that
somehow the team is able to do more than the individuals could do themselves, then they buy
on kind of in terms of the process. So that's the goal that you have to have is to achieve that.
And that means that you have to realize parts of what you're trying to do that require
not that one person couldn't do it. It requires the combined talents to be able to do something
that neither of them could do themselves. And we have a lot of that kind of thing. And I think,
I'm going to build into some of the examples that I gave you. And so the key almost in anything you
do is the people themselves, right? So in our case, the first and most important was to attract,
to spend years of their life on this, the best possible people in the world to do it.
So the only way to convince them is that somehow it's better and more interesting for them than
what they could do themselves. And so that's part of this idea.
I got you. Yeah, that's powerful. But nevertheless, there's best people in the world, there's egos.
Is there something to be said about managing egos?
The human problem is always the hardest. And so that's an art, not a science, I think.
I think the fact here that combined, there was a romantic goal that we had to do something that
people hadn't done before, which was important scientifically and a huge challenge enabled us
to say take and get, I mean, just to take an example, we use the light to go in this thing,
comes from lasers. We need a certain kind of laser. So the kind of laser that we use,
there were three different institutions in the world that had the experts that do this,
maybe in competition with each other. So we got all three to join together and work with us
to work on this as an example. And they had the thing that they were working together on a kind
of object that they wouldn't have otherwise. And we're part of a bigger team where they could
discover something that isn't even engineers. These are engineers that do lasers. And they're
part of our laser physicists. So could you describe the moment or the period of time
when finally this incredible creation of human beings led to a detection of gravitational waves?
It's a long story. Unfortunately, this is a part that we started failures along the way kind of
thing or all failures. That's all that's built into it. If you're not a mechanical engineer,
you build on your failures. That's expected. So we're trying things that no one's done before.
So it's technically not just gravitational waves. And so it's built on failures. But anyway, we did
it before me, even the people did R&D on the concepts. But starting in 1994, we got money
from the National Science Foundation to build this thing. It took about five years to build it. So
by 1999, we had built the basic unit. It did not have active seismic isolation at that stage. Didn't
have some other things that we have now. What we did at the beginning was stick to technologies that
we had at least enough knowledge that we could make work or had tested in our own laboratories.
And so then we put together the instrument. We made it work. It didn't work very well,
but it worked. And we didn't see any gravitational waves. Then we figured out what limited us.
And we went through this every year for almost 10 years, never seeing gravitational waves.
We would run it, looking for gravitational waves for months,
learn what limited us, fix it for months, then run it again. Eventually, we knew we had to take
another big step. And that's when we made several changes, including adding these active seismic
isolation, which turned out to be a key. And we fortunately got the National Science Foundation
to give us another couple hundred million dollars, 100 million more. And we rebuilt it,
our fixed, our improved it. And then in 2015, we turned it on. And we almost instantly saw
this first collision of two black holes. And then we went through a process of
do we believe what we've seen? Yeah, I think you're one of the people that went through that
process. It sounds like some people immediately believed it. Yeah. And then you were like us.
As human beings, we all have different reactions to almost anything. And so quite a few of my
colleagues had a Eureka moment immediately. I mean, it's the figure that we put in our paper
first is just data. We didn't have to go through fancy computer programs to do anything. And we
showed next to it the calculations of Einstein's equations. It looks just like what we detected.
And we did it in two different detectors halfway across the U.S. So it was pretty convincing,
but you don't want to fool yourself. So being a scientist, for me, we had to go through and try
to understand that the instrument itself, which was new, I said we had rebuilt it, couldn't somehow
generate things that look like this. That took some tests. And then the second, you'll appreciate
more. We had to somehow convince ourselves we weren't hacked in some clever way. Cyber security
question. Yeah. Even though we're not on the internet, but yeah. No, it can be physical access
too. Yeah. That's fascinating. It's fascinating that you would think about that. I mean, not enough.
I mean, because it matches prediction. So the chances of it actually being manipulated is very,
very low. But nevertheless, we still could have disgruntled all graduate students who had worked
with us earlier. Who want you to, I don't know how that's supposed to embarrass you. I suppose,
yeah, I suppose I see. But about what I think you said, within a month, you kind of convinced
yourself officially. Within a month, we convinced ourselves. We kept a thousand collaborators quiet
during that time. Then we spent another month or so trying to understand what we'd seen so that we
could do the science with it instead of just putting it out to the world and let somebody else
understand that it was two black holes and what it was. The fact that a thousand collaborators were
quiet is a really strong indication that this is a really close knit team. Yeah. And they're
around the world. Either a strong knit or a tight knit or had a strong dictatorship or something.
Yeah. Either fear or love. You can rule by fear or love. You can go back to Machiavelli.
This is really exciting that that's a success story because it didn't have to be a success
story. I mean, eventually, perhaps you could say it would be an event, but it could have taken it
over a century to get it. Yeah. And it's only downhill now. What do you mean? You mean with
gravitational waves? Well, yeah. Well, now we're off because of the pandemic. But when we turned
off, we were seeing some sort of gravitational wave event each week. And now we're fixing,
we're fixing, we're adding features where it'll probably be when we turn back on next year, it'll
probably be every one, every couple of days. And they're not all the same. So it's learning about
what's out there in gravity instead of just optics. And so it's all great. We're only limited by
the fantastic thing other than that this is a great field and it's all new and so forth is
that experimentally, the great thing is that we're limited by technology and technical limitations,
not by science. So another really important discovery that was made before ours was what's
called the Higgs boson, made on the big accelerator at CERN. This huge accelerator, they discovered
a really important thing. We have Einstein's equation, E equals MC squared. So energy makes
mass or mass can make energy and that's the bomb. But the mechanism by which that happens,
not vision, but how do you create mass from energy was never understood until there was
a theory of it about 70 years ago now. And so they discovered it's named after a man named
Higgs. It's called the Higgs boson. And so it was discovered. But since that time, and I worked on
those experiments, since that time, they haven't been able to progress very much further, a little
bit, but not a lot further. And the difference is that we're really lucky. We're in what we're
doing in that there, you see this Higgs boson, but there's tremendous amount of other physics
that goes on and you have to pick out the needle and the haystack kind of physics. You can't make
the physics go away. It's there. In our case, we have a very weak signal, but once we get good enough
to see it, it's weak compared to where we've reduced the background. But the background is not physics.
It's just technology. It's getting ourselves better isolated from the earth or getting a
more powerful laser. And so each time, each since 2015, when we saw the first one, we continually
can make improvements that are enabling us to turn this into a real science to do astronomy,
a new kind of astronomy. It's a little like astronomy. I mean, Galileo started the field.
I mean, he basically took lenses that were made for classes and he didn't invent the first telescope,
but made a telescope, looked at Neptune and saw that it had four moons. That was the birth of
not just using your eyes to understand what's out there. And since that time, we've made better
and better telescopes, obviously, and astronomy thrives. And in a similar way, we're starting to
be able to crawl, but we're starting to be able to do that with gravitational waves. And it's
going to be more and more that we can do as we can make better and better instruments because,
as I say, it's not limited by picking it out of others. Yeah, it's not limited by the physics.
So you have an optimism about engineering that as human progress marches on,
engineering will always find a way to build a large enough device, accurate enough device
to detect the physics. As long as it's not limited by physics, yeah, they'll do it.
So you two other folks and the entire team won the Nobel Prize for this big effort.
There's a million questions I can ask for, but looking back,
where does the Nobel Prize fit into all of this? If you think hundreds of years from now,
I venture to say that people will not remember the winners of a prize,
but they'll remember creations like these. Maybe I'm romanticizing engineering,
but I guess I want to ask how important is the Nobel Prize in all of this?
Well, that's a complicated question. As a physicist, it's something if you're
trying to win a Nobel Prize, forget it because they give one a year. So there's been 200 physicists
who have won the Nobel Prize since 1900. So things just have to fall right. So your goal
cannot be to win an Nobel Prize. It wasn't my dream. It's tremendous for science. I mean,
why the Nobel Prize for a guy that made dynamite and stuff is what it is. It's a long story, but
it's the one day a year where actually the science that people have done is all over the world and
so forth. Forget about the people again. It is really good for science.
Celebrating science.
It celebrates science for several days, different fields, chemistry, medicine, and so forth.
Everybody doesn't understand everything about these. They're generally fairly abstract, but then
it's on the front page of newspapers around the world. So it's really good for science.
It's not easy to get science on the front page of the New York Times. It's not there.
It should be, but it's not. So the Nobel Prize is important in that way.
Otherwise, I have a certain celebrity that I didn't have before.
And now you get to be a celebrity that advertises science. It's a mechanism to
remind us how incredible, how much credit science deserves and everything.
Well, it has a little bit more. One thing I didn't expect, which is good, is that we have a
government. I'm not picking on ours necessarily, but it's true of all governments are not run by
scientists. In our case, it's run by lawyers and businessmen. And at best, they may have an
aide or something that knows a little science. So our country is, and all countries, are hardly
hardly taken into account science in making decisions. And having a Nobel Prize, the
people in those positions actually listen. So you have more influence. I don't care
whether it's about global warming or what the issue is. There's some influence, which is lacking
otherwise. And people pay attention to what I say. If I talk about global warming, they wouldn't have
before I had the Nobel Prize. Yeah, this is very true. You're like the celebrities who talk.
Celebrity has power. Celebrity has power. And that's important. And that's a good thing.
That's a good thing, yeah. Singling out people. I mean, on the other side of it,
singling out people has all kinds of, whether it's for Academy Awards or for this,
have unfairness and arbitrariness and so forth and so on. So that's the other side of the coin.
Just like you said, especially with the huge experimental projects like this,
it's a large team. And it does the nature of the Nobel Prizes singles out a few individuals to
represent the team. Yeah. Nevertheless, it's a beautiful thing. What are ways to improve LIGO
in the future, increase the sensitivity? I've seen a few ideas that are kind of fascinating.
Is, are you interested in them? Sort of looking, I'm not speaking about five years.
Perhaps you could speak to the next five years, but also the next hundred years.
Yeah. So let me talk to both the instrument and the science. Sure. So that's, they go hand in hand.
I mean, the thing that I said is if we make it better, we see more kinds of weaker objects and
we do astronomy. Okay. We're very motivated to make a new instrument, which will be a big step,
the next step, like making a new kind of telescopers. And the ideas of what that instrument should be
haven't converged yet. There's different ideas in Europe. They've done more work to kind of
develop the ideas, but they're different from ours and we have ideas. So, but I think over
the next few years we'll develop those. The idea is to make an instrument that's at least 10 times
better than what we have, what we can do with this instrument, 10 times better than that.
10 times better means you can look 10 times further out. 10 times further out is 1000 times more
volume. So you're seeing much, much more of the universe. The big change is that if you can see
far out, you see further back in history. Yeah. You're traveling back in time.
Yeah. And so we can start to do what we call cosmology instead of astronomy or astrophysics.
Cosmology is really the study of the evolution of the... Oh, interesting. Yeah. And so then you
can start to hope to get to the important problems having to do with how the universe began, how it
evolved and so forth, which we really only study now with optical instruments or electromagnetic
waves. And early in the universe, those were blocked because basically it wasn't transparent,
so the photons couldn't get out when everything was too dense.
What do you think, sorry on this tangent, what do you think an understanding of gravitational
waves from earlier in the universe can help us understand about the Big Bang and all that kind
of stuff? Yeah. Yeah. That's so... But it's a non... It's another perspective on the thing. Is there
some insights you think could be revealed just to help a layman understand? Sure. First, we
don't understand. We use the word Big Bang. We don't understand the physics of what the Big Bang
itself was. So I think my... And in the early stage, there were particles and there was a huge
amount of gravity and mass being made. And so the big... So I'll say two things. One is, how did it
all start? How did it happen? And I'll give you at least one example that we don't understand,
what we should understand. We don't know why we're here. Yes. No, we do not.
I don't mean it philosophically. I mean it in terms of physics. Okay? Now, what do I mean by
that? If I go into my laboratory at CERN or somewhere and I collide particles together or put
energy together, I make as much antimatter as matter. Why? Antimatter then annihilates matter
and makes energy. So in the early universe there, you made somehow, somehow a lot of matter and
antimatter, but there was an asymmetry. Somehow there was more matter and antimatter. Then matter
and antimatter annihilated each other. At least that's what we think. And there was only matter
left over and we live in a universe that we see. This all matter. We don't have any idea. We have
an idea, but we don't have any way to understand that at the present time with the physics that we
know. Can I ask a dumb question? Does antimatter have anything like a gravitational field to
send signals? So how does this asymmetry of matter and antimatter could be investigated or further
understood by observing gravitational fields or weirdnesses in gravitational fields? I think that
in principle, if there were anti-neutron stars instead of just neutron stars,
we would see different kind of signals, but it didn't get to that. We live in a universe that
we've done enough looking because we don't see antimatter, anti-protons anywhere, no matter what
we look at, that it's all made out of matter. There is no antimatter except when we go in our
laboratories. But when we go in our laboratories, we make as much antimatter as matter. So there's
something about the early universe that made this asymmetry. So we can't even explain why we're here.
That's what I meant. Physics-wise, not in terms of how we evolved and all that kind of stuff.
So there might be inklings of
the physics that gravitational waves would do. So gravitational waves don't get obstructed like
light. So I said light only goes to 300,000 years. So it goes back to the beginning. So if you could
study the early universe with gravitational waves, we can't do that yet. Then it took 400 years to
be able to do that with optical. But then you can really understand the very, maybe understand the
very early universe. So in terms of questions like why we're here or what the Big Bang was,
we can in principle study that with gravitational waves. So to keep moving in this direction,
it's a unique kind of way to understand our universe. So you think there's more Nobel Prize level
ideas to be discovered in relation to gravitational waves? I'd be shocked if there isn't. Not even
going to that, which is a very long range problem. But I think that we only see with electromagnetic
waves four percent of what's out there. There must be, we looked for things that we knew should be
there. There should be, I would be shocked if there wasn't physics, objects, science and with
gravity that doesn't show up in everything we do with telescopes. So I think we're just limited by
not having powerful enough instruments yet to do this. Do you have a preference? I keep seeing this
E. Lisa idea. Yeah. Is it, do you have a preference for earthbound or space faring
mechanisms for? They're complementary. It's a little bit like, it's completely analogous to what's
been done in astronomy. So astronomy from the time of Galileo was done with visible light.
The big advances in astronomy in the last 50 years are because we have instruments that look at the
infrared, microwave, ultraviolet and so forth. So looking at different wavelengths has been important.
Basically going into space means that we'll look at instead of the audio band, which we look at,
as we said on the Earth's surface, we'll look at lower frequencies. So it's completely complementary
and it starts to be looking at different frequencies just like we do with astronomy.
It seems almost incredible to me engineering wise, just like on Earth,
to send something that's kilometers across into space. Is that harder to engineer?
Then it actually is a little different. It's three satellites separated by hundreds of thousands
of kilometers and they send a laser beam from one to the other. And if the distance, if the
triangle changes shape a little bit, they detect that from a passenger. Sorry, did you say hundreds
of thousands of kilometers? Yeah. Sending lasers to each other. Okay. It's just engineering.
Is it possible though? Yes. That's just incredible because they have to maintain,
I mean the precision here is probably, there might be some more, what is it? Maybe noise is a smaller
problem. I guess there's no vibration to worry about like seismic stuff. So getting away from
Earth, maybe you get away from the seismic stuff. Yeah, those parts are easier. They don't have to
measure it as accurately at low frequencies, but they have a lot of tough engineering problems.
In order to detect that the gravitational waves affect things, the sensors have to be
what we call free masses, just like ours, are isolated from the Earth. They have to isolate it
from the satellite. And that's a hard problem. They have to do that pretty not as well as we
have to do it, but very well. And they've done a test mission and the engineering seems to be
at least in principle in hand. This will be in the 2030s. This is incredible. Let me ask about
black holes. So what we're talking about is observing orbiting black holes. I saw the
terminology of binary black hole systems. That's when they're dancing. We're going
around each other just like the Earth around the sun. Is that weird that there's black holes
going around each other? So the finding binary systems of stars is similar to finding binary
systems of black holes. Well, they were once stars. So we haven't said what a black hole is
physically yet. Yeah, what's a black hole? So black hole is first, it's a mathematical concept
or a physical concept. And that is a region of space. So it's simply a region of space where
the curvature of spacetime in the gravitational field is so strong that nothing can get out,
yeah, including light. And there's light gets bent in gravitational, if the gravitational,
if the spacetime is warped enough. And so even light gets bent around and stays in it. So that's
concept of a black hole. So it's not a, and maybe you can make, maybe it's a concept that didn't
say how they come about. And there could be different ways they come about. The ones that
we are seeing, there's a, we're not sure. That's what we're trying to learn now is what they,
but the general expectation is that they come, these black holes happen when a star dies.
So what does that mean that a star dies? What happens? A star like our sun
basically makes heat and light by fusion. It's made up. And as it burns, it burns up the hydrogen
and then the helium and then, and slowly works its way up to the heavier and heavier elements that
are in the star. And when it gets up to iron, the fusion process doesn't work anymore. And so the
stars die and that happens to stars. And then they do what's called a supernova. What happens then
is that a star is a delicate balance between an outward pressure from fusion and light and burning
and an inward pressure of gravity trying to pull the masses together. Once it burns itself out,
it goes and it collapses. And that's a supernova. When it collapses, all the mass that was there is
in a very much smaller space. And if a star, if you do the calculations, if a star is big enough,
that can create a strong enough gravitational field to make a black hole. Our sun won't.
It's too small. Too small. And we don't know exactly what it, but it's usually thought that a star has
to be at least three times as big as our sun to make a black hole. But that's the physical way
there. You can make black holes. That's the first explanation that one would give for the,
for what we see. But it's not necessarily true. We're not sure yet.
What we see in terms of for the origins of the black holes?
No, the black holes that we see in gravitational waves.
But you're also looking for the ones who are binary solar systems?
So they're binary systems, but they could have been made from binary stars. So there's binary
stars around. So that's the first explanation is that that's what they are. Other explanation,
but what we see has some puzzles. This is the way science works, I guess. We see heavier ones than
up to, we've seen one system that was 140 times the mass of our own sun. That's not believed to be
possible with the parent being a big star because big stars can only be so big or they
are unstable. It's just the fact that they live in an environment that makes them unstable.
So the fact that we see bigger ones, they maybe come from something else. It's possible that they
were made in a different way by little ones eating each other up, or maybe they came with
the big bang, what we call primordial, which means they're really different. They came from that.
We don't know at this point. If they came with a big bang, then maybe they account for
what we call dark matter or some of it. There's a lot of them, because there's a lot
of dark matter. But double gravitational waves give you any kind of intuition about the origin
of these oscillating? We think that if we see the distributions enough of them, the distributions of
their masses, the distributions of how they're spinning, so we can actually measure when they're
going around each other, whether they're spinning like this or around. The direction of the spin?
Or no, the orientation? Whether the whole system has any wobbles.
So this is now, okay. We're doing that. And then you're constantly kind of crawling back and back
in time. And we're crawling back in time and seeing how many there are as we go back. And so
do they point back? So you're like, what is that discipline called, cartography or something? You're
like mapping the early universe via the lens of gravitational waves.
Not yet the early universe, but it's back earlier. So black holes are this mathematical
phenomenon, but they come about in different ways. We have a huge black hole at the center of our
galaxy and other galaxies. Those probably were made some other way. We don't know when the galaxies
themselves had to do with the formation of galaxies. We don't really know. So the fact that
we use the word black hole, the origin of black holes might be quite different depending on
how they happen. They just have to, in the end, have a gravitational field that will bend everything
in. How do you feel about black holes as a human being? There's this thing that's nearly infinitely
dense. It doesn't let light escape. Isn't that kind of terrifying? It feels like the stuff of
nightmares. I think it's an opportunity to do what exactly? So like the early universe is an
opportunity. In fact, we can study the early universe. We can learn things like I told you
and hear again. We have an embarrassing situation in physics. We have two wonderful theories of
physics, one based on quantum mechanics, quantum field theory. We can go to a big accelerator
like at CERN and smash particles together and almost explain anything that happens
beautifully using quantum field theory and quantum mechanics. Then we have another theory of physics
called general relativity, which is what we've been talking about most of the time,
which is fantastic at describing things at high velocities, long distances,
and so forth. So that's not the way it's supposed to be. We're trying to create a theory of physics,
not two theories of physics. So we have an embarrassment that we have two different theories
of physics. People have tried to make a unified theory, what they call a unified theory. You've
heard those words for decades. They still haven't. That's been primarily done theoretically, or tried
these people actively do that. My personal belief is that like much of physics, we need some clues.
So we need some experimental evidence. So where is their place? If we go to CERN and do those
experiments, gravitational waves or general relativity don't matter. If we go to study our
black holes, elementary particle physics doesn't matter. We're studying these huge objects. So
where might we have a place where both phenomenon have to be satisfied? An example is black holes.
Inside black holes. Yeah. So we can't do that today. But when I think of black hole, it's a potential
treasure chest of understanding the fundamental problems of physics and maybe can give us clues
to how we bring to the embarrassment of having two theories of physics together.
That's my own romantic idea. What's the worst that could happen? It's so enticing. Just go in and look.
Look, do you think how far are we away from figuring out the unified theory of physics,
the theory of everything? What's your sense? Who will solve it? Like what discipline will solve it?
Yeah. I think so little progress has been made
without more experimental clues, as I said, that we're just not able to
say that we're close without some clues. The best, the closest, the most popular theory these days
that might lead to that is called string theory. And the problem with string theory is it works,
it solves a lot of beautiful mathematical problems we have in physics. And it's very satisfying
theoretically. But it has almost no predictive, maybe no predictive ability because it is a theory
that works in 11 dimensions. We live in a physical world of three space and one time dimension. In
order to make predictions in our world with string theory, you have to somehow get rid of these other
seven dimensions. That's done mathematically by saying they curl up on each other on scales that
are too small to affect anything here. But how you do that, and that's okay, that's an okay argument,
but how you do that is not unique. So that means if I start with that theory and I go to our world
here, I can't uniquely go to it. Which means it's not predictive. It's not predictive.
And that's a killer. And string theory is, it seems like from my outsider's perspective,
is lost favor over the years, perhaps because of this very idea. It's a lack of predictive power.
I mean, that science has to connect to something where you make predictions as beautiful as it
might be. So I don't think we're close. I think we need some experimental clues. It may be that
information on something we don't understand presently at all like dark energy or probably not
dark matter, but dark energy or something might give us some ideas. But I don't think we're,
I can't envision right now in the short term, meaning the horizon that we can see
how we're going to bring these two theories together.
A kind of two-part question, maybe just asking the same thing in two different ways.
One question is, do you have hope that humans will colonize the galaxy, so expand out, become a
multiplanetary species? Another way of asking that from a gravitational and a propulsion
perspective, do you think we'll come up with ways to travel closer to the speed of light or maybe
faster than the speed of light, which would make it a whole heck of a lot easier to expand out into
the universe? Yeah. Well, I think that's very futuristic. I think we're not that far from
being able to make a one-way trip to Mars. That's then a question of whether people are
willing to send somebody on a one-way trip. Oh, I think they are. I think there's a lot of the
explorers burn bright with their hearts. Yeah, exactly. There's a lot of people willing to die
for the opportunity to explore new territory. Yeah. So this recent landing on Mars is pretty
impressive. They have a little helicopter that can fly around. You can imagine in the not too
distant future that you could have, I don't think civilizations colonizing, I can envision,
but I can envision something more like the South Pole. We haven't colonized Antarctica because it's
all ice and cold and so forth, but we have stations. So we have a station that's self-sustaining at
the South Pole that I've been there. Wow, really? Yeah. What's that like? Because there's parallels
there to go to Mars. It's fantastic. What's the journey like? The journey involves going. The
South Pole station is run in the US by the National Science Foundation. I went because I was on the
National Science Board that runs the National Science Foundation. And so you get a VIP trip,
if you're healthy enough, to the South Pole to see it, which I took. You fly from the US to
Australia to Christchurch in Southern Australia. And from there, you fly to McMurdo Station,
which is on the coast. And it's the station with about 1,000 people right on the coast of Antarctica.
It's about a seven or eight hour flight and they can't predict the weather. So when I flew from
Christchurch to McMurdo Station, they tell you in advance, you do it in a military aircraft,
they tell you in advance that they can't predict whether they can land because they have to land
on reassuring. Yeah. And so about halfway, the pilot got on and said, sorry, they call it a boomerang
flight. Boomerang goes out and goes back. So we had to stay a little while in Christchurch,
but then we eventually went to McMurdo Station and then flew to the South Pole. The South Pole
itself is, when I was there, it was minus 51 degrees. That was summer. It has zero humidity.
And it's about 11,000 feet altitude because it's never warm enough for anything to melt,
so it doesn't snow very much, but it's about 11,000 feet of snowpack. So you land in a place
that's high altitude, cold as could be, and incredibly dry, which means you have a physical
adjustment. The place itself is fantastic. They have this great station there. They do
astronomy at the South Pole. Nature-wise, is it beautiful? What's the experience like,
or is it like visiting any town? No, it's very small. There's only less than 100 people there,
even when I was there. There were about 50 or 60 there, and in the winter, there's less,
half of that. They're winter. It gets really cold. But it's a station. We haven't gone beyond that.
On the coast of Antarctica, they have greenhouses and they're self-sustaining in McMurdo Station,
but we haven't really settled more than that kind of thing in Antarctica, which is a big
plot, a big piece of land. So I can't envision colonizing people living so much as much as I can
see of the equivalent of the South Pole Station. Well, in the computing world, there's an idea of
backing up your data, and then you want to do off-site backup to make sure that if your whole
house burns down, that you can have a backup off-site of the data. I think the difference in
Antarctica and Mars is Mars is an off-site backup, that if we have nuclear war, whatever the heck
might happen here on Earth, it'd be nice to have a backup elsewhere. It'd be nice to have a large
enough colony where we sent a variety of people, except a few silly astronauts in suits, have an
actual vibrant, get a few musicians and artists up there, maybe one or two computer scientists,
those are essential, maybe even a physicist. Maybe not. So that comes back to something you talked
about earlier, which is the paradox, family's paradox, because you talked about having to
escape. One number you don't know how to use in Fermi's calculation or Drake who's done it better
is how long do civilizations last? We've barely gotten to where we can communicate with
electricity and magnetism, and maybe we'll wipe ourselves out pretty soon. Are you hopeful in
general? Do you think we've got another couple hundred years at least, or are you worried?
Well, no, I'm hopeful, but I don't know if I'm hopeful in the long term. If you say, are we able
to go for another couple thousand years, I'm not sure. I think we have where we started,
the fact that we can do things that don't allow us to keep going, or there can be,
whether it ends up being a virus that we create, or ends up being the equivalent of nuclear war,
or something else. It's not clear that we can control things well enough.
So speaking of really cold conditions and not being hopeful and eventual suffering and
destruction of the human species, let me ask you about Russian literature. You mentioned,
how's that for transition? I'm doing my best here. You mentioned that you used to love literature
when you were younger, or hoping to be a writer yourself. That was the motivation,
and some of the books I've seen that you listed that were inspiring to you was from Russian
literature, like Tolstoy, Dostoevsky, Solzhenitsyn. Maybe in general, you can speak to your
fascination with Russian literature, or in general, would you picked up from those?
I'm not surprised you picked up on the Russian literature with your background.
You should be surprised that didn't make the entire conversation about this. That's the
real surprise. I didn't really become a physicist or want to go in science until I started college.
So when I was younger, I was good at math and that kind of stuff. But I didn't really, I came
from a family, nobody went to college and I didn't have any mentors. But I'd like to read when I was
really young. And so when I was very young, I read, I always carried it around a pocket book and
read it. And my mother read these mystery stories and I got bored by those eventually. And then I
discovered real literature. I don't know at what age, but about 12 or 13. And so then I started
reading good literature. And there's nothing better than Russian literature, of course.
And reading good literature. So I read quite a bit of Russian literature at that time.
And so you asked me about, well, I don't know, say a few words, Dostoevsky. So what about Dostoevsky?
For me, Dostoevsky was important. I mean, I've read a lot of literature because it's kind of
the other thing I do with my life. And he made two incredible, in addition to his own literature,
he influenced literature tremendously by having, I don't know how to pronounce polyphony. So he's
the first real serious author that had multiple narrators. And that's a, that he absolutely is
the first. And he also was the first, he began existential literature. So the most important
book that I've read in the last year when I've been forced to be isolated was existential literature.
It was, I decided to reread Camus the Plague. Oh yeah, that's a great book. It's a great book.
And it's right now to read it. It's fantastic. I think that book is about love, actually,
love for humanity. It is, but it has all the, it has all the, if you haven't read it in recent
years, I had read it before, of course, but to read it during this, because it's about a plague.
So it's really fantastic to read now. But that reminds me of, you know, he was a great existentialist,
but the beginning of existential literature was Dostoevsky. So in addition to his own,
you know, great novels, he had a tremendous impact on literature.
And there's also, for Dostoevsky, unlike most other existentialists, he was at least in part
religious. I mean, their religiosity permeated his idea. I mean, one of my favorite books of his
is The Idiot, which is a Christ-like figure in there. Well, there's Prince Mishkin, is that
it? Prince Mishkin, yeah. Yeah, Mishkin. That's one thing about, you read it in English, I presume.
Yeah, yeah. Yeah, so that's the names. That's what gets a lot of people. There's so many names,
so hard to pronounce. You have to remember all of them. It's like, you have the same problem.
But he was a great character, so that, yeah. I kind of, I have a connection with him, because I often,
then the title of the book, The Idiot, is, I kind of, I often call myself an idiot,
because that's how I feel. I feel so naive about this world. And I'm not sure, I'm not sure why
that is. Maybe it's genetic or so on, but I have a connection, a spiritual connection to that
character. To Mishkin. To Mishkin, yeah. That you're just in the- But he was far from an idiot.
No, in some sense, in some sense. But in another sense, maybe not of this world. In another sense,
he was. Yeah. I mean, he was a bumbler, a bumbler. Yeah. But you also mentioned Solzhenitsyn.
Yes. Very interesting. Yes, he did. And he always confused me. Of course, he was really,
really important in writing about the Stalin, and first getting in trouble. And then he later,
he wrote about Stalin in a way, I forget what it was, what the book was, in a way that was
very critical of Lenin. Yeah, he's evolved through the years, and he actually showed support for
Putin eventually. It was a very interesting transition he took. No, journey he took through
thinking about Russia and the Soviet Union. But I think what I get from him is basic,
it's like Viktor Frankl has a man search for meaning. I have a similar kind of sense of
the cruelty of human nature, cruelty of indifference, but also the ability to find happiness in the
small joys of life. There's nothing like a prison camp that makes you realize you could
still be happy with a very, very little. Well, yeah, his description of how to make,
how to go through a day and actually enjoy it in a prison camp is pretty amazing.
And some prison camp, I mean, it's the worst of the worst. And also just,
I do think about the role of authoritarian states in hopeful, idealistic systems somehow
leading to the suffering of millions. And this might be arguable, but I think a lot of people
believe that Stalin, I think genuinely believed that he's doing good for the world,
and he wasn't. It's a very valuable lesson that even evil people think they're doing good.
Otherwise, it's too difficult to do the evil. The best way to do evil is to believe framing
in a way like you're doing good. And then this is a very clear picture of that, which is the
gulags. And Solzhenitsyn is one of the best people to reveal that. Yeah. The most recent
thing I read, it isn't actually fiction, was the woman, I can't remember her name, who got the
Nobel Prize about within the last five years. I don't know whether she's Ukrainian or Russian,
but their interviews, have you read that? Interview of Ukrainian survivors of...
Well, I think she may be originally Ukrainian. The book's written in Russian and translated
in English, and many of the interviews are in Moscow and places. But she won the Nobel Prize
within the last five years or so. But what's interesting is that these are people of all
different ages, all different occupations and so forth, and they're reflecting on their reaction
to basically the present Soviet system, the system they live with before. There's a lot of
looking back by a lot of them with, well, it being much better before.
Yeah. I don't know what... In America, we think we know the right answer, what it means to be,
to build a better world. I'm not so sure. I think we're all just trying to figure it out.
Yeah, there's... We're doing our best. I think you're right.
Is there advice you can give to young people today, besides reading Russian literature at a
young age, about how to find their way in life, how to find success in career or just life in general?
I just... My own belief, it may not be very deep, but I believe it. I think you should follow your
dreams and you should have dreams and follow your dreams, if you can, to the extent that you can.
And we spend a lot of our time doing something with ourselves, in my case, physics, in your case,
I don't know, whatever it is, machine learning and this. We should have fun.
What was... Wait, wait, wait. Follow your dreams. What dream did you have?
Well, originally, I was... Because you didn't follow your dream.
I changed along the way. I was going to be, but I changed.
What happened? That was... What happened? Oh, I read... I decided to take the most
serious literature course in my high school, which was a mistake. I'd probably be a
second-right writer now. And... Could be a Nobel Prize-winning writer.
And the book that we read, even though I had read Russian novels, I was 15, I think.
...cured me from being a novelist.
Destroyed your dream?
Yes.
Cured you? Okay. What was the book?
Moby Dick.
Okay.
So why Moby Dick?
Yeah, why?
So I've read it since and it's a great novel. Maybe it's as good as the Russian novel.
I've never made it through. It was too long.
Okay. Your words are going to mesh with what I say.
Excellent.
And you may have the same problem at an older age. Maybe that's why I'm not a writer.
It may be. So the problem is, Moby Dick is... What I remember was there was a chapter,
there was maybe 100 pages long, all describing this why there was Ahab and the White Whale.
And it was the battle between Ahab with his wooden peg leg and the White Whale.
And there was a chapter that was 100 pages long in my memory. I don't know how long it really was.
That described in detail though, Great White Whale and what he was doing and what his fins
were like and this and that. And it was so incredibly boring, the word you used,
that I thought, if this is great literature, screw it.
Oh, fascinating.
Okay. Now why did I have a problem? I know now in reflection because I still read a lot.
And I read that novel after I was 30 or 40 years old.
And the problem was simple. I diagnosed what the problem was.
That novel, in contrast to the Russian novels, which are very realistic and point of view,
is one huge metaphor.
Oh, yeah.
Yeah. At 15 years old, I probably didn't know the word and I certainly didn't know the meaning
of a metaphor.
Yeah, like why do I care about a fish? Why are you telling me all about this fish?
Yeah, exactly. It's one big metaphor. So reading it later as a metaphor, I could really enjoy it.
But the teacher gave me the wrong book or maybe it was the right book because I went into physics.
But it was truly, I think, I may oversimplify, but it was really that I was too young to read
that book because not too young to read the Russian novels, interestingly, but too young
to read that because I probably didn't even know the word and I certainly didn't understand it as
a metaphor.
Well, in terms of fish, I recommend people read Old Man in the Sea much shorter, much better.
Still metaphor though. But you can read it just as a story about a guy catching a fish and it's
still fun to read. I had the same experience as you, not with Moby Dick, but later in college,
I took a course on James Joyce. I don't know why. I was majoring in computer science and took a
course on James Joyce. And I was kept being told that he is widely considered by many considered
to be the greatest literary writer of the 20th century. And I kept reading, I think,
so his short story is The Dead, I think it's called. It was very good. Well, not very good,
but pretty good. And then Ulysses. It's actually very good. It is very good. I mean, The Dead,
the final story, it still rings with me today. But then Ulysses was, I got through Ulysses with
the help of some cliff notes and so on. And so I did Ulysses and then Finnegan's Wake. The moment
I started Finnegan's Wake, I said, this is stupid. That's when I went full into, I don't know,
that's when I went full Kafka, Bukowski, people who just talk about the darkness of the human
condition in the fewest words possible and without any of the music of language. So it was a turning
point as well. I wonder when is the right time to appreciate the beauty of language,
like even Shakespeare. I was very much off-put by Shakespeare in high school,
and only later I started to appreciate its value in the same way. Let me ask you a ridiculous
question. I mean, because you've read our literature, let me ask this one last question. I might be
lying. There might be a couple more. But what do you think is the meaning of this whole thing?
You got a Nobel Prize for looking out into the, trying to reach back into the beginning of the
universe, listening to the gravitational waves, but that still doesn't answer the why. Why are we
here beyond just the matter and anti-matter, the philosophical question? The philosophical
question about the meaning of life I'm probably not really good at. I think that
the individual meaning, I would say rather simplistically, is whether you've made
a difference, a positive difference, I'd say, for anything besides yourself,
meaning you could have been important to other people, or you could have discovered
gravitational waves that matter to other people or something, but something beyond just existing
on the earth as an individual. So your life has meaning if you have affected
either knowledge or people or something beyond yourself. It's a simplistic statement,
but it's about as good as I am. In all of its simplicity, it may be
very true. Do you think about, does it make you sad that this ride ends? Do you think about your
mortality? Yeah. Are you afraid of it? I'm not exactly afraid of it, but saddened by it and
I'm old enough to know that I've lived most of my life and I enjoy being alive. I can imagine
being sick and not wanting to be alive, but I'm not. It's been a good ride.
Yeah. I'm not happy to see it come to an end. I'd like to see it prolong, but I don't
fear the dying itself or that kind of thing. It's more, I'd like to prolong
what is, I think, a good life that I'm living and still living.
Okay. It's sad to think that the finiteness of it
is the thing that makes it special and also sad to have, to me at least, it's kind of,
I don't think I'm using too strong of a word, but it's kind of terrifying the uncertainty of it,
the mystery of it. The mystery of death. The mystery of death. When we're talking about
the mystery of black holes that's somehow distant, that's somehow out there and the
mystery of our own. But even life, the mystery of consciousness, I find so hard to deal with too.
I mean, it's not as painful. I mean, we're conscious, but the whole magic of life,
we can understand about consciousness where we can actually think and so forth. It's
pretty, it's such, it seems like such a beautiful gift that it really sucks that
we get to let go of it. We'll have to let go of it. What do you hope your legacy is?
As I'm sure they will, aliens when they visit and humans have destroyed all of human civilization,
aliens read about you and encyclopedia that will leave behind. What do you hope it says?
Well, I would hope they, to the extent that they evaluated me, felt that I helped move
science forward as a tangible contribution and that I served as a good role model for
how humans should live their lives. And we're part of creating one of the most incredible things
humans have ever created. So yes, there's the science. That's the Fermi thing, right?
And the instrument, I guess. And the instrument. The instrument is a magical creation,
not just by a human, by a collection of humans. The collaboration is, that's humanity at its best.
I do hope, I do hope we last quite a bit longer, but if we don't,
this is a good thing to remember humans by. At least they built that thing.
That's pretty impressive. Barry, this was an amazing conversation. Thank you so much for
wasting your time and explaining so many things so well. I appreciate your time today. Thank you.
Thanks for listening to this conversation with Barry Barish. To support this podcast,
please check out our sponsors in the description. And now let me leave you some words from Werner
Heisenberg, a theoretical physicist and one of the key pioneers of quantum mechanics.
Not only is the universe stranger than we think, it is stranger than we can think.
Thank you for listening and hope to see you next time.