Kind: captions
Language: en
Black holes curve space and time around
them in the way that we've been
describing. Things follow along the
curves in space. If the black holes move
around, the curves have to follow them,
right? But they can't travel faster than
the speed of light either. So what
happens is black holes, let's say, move
around. Maybe I've got two black holes
in orbit around each other. That can
happen. It takes a while. A wave is
created in the actual shape of space.
And that wave follows the black holes.
Those black holes are undulating.
Eventually, those two black holes will
merge. And as we were talking about, it
doesn't take an infinite time, even
though there's time dilation because
they're both so big. They're really
deforming spaceime a lot. I don't have a
little tiny marble falling across an
event horizon. I have two event
horizons. And in the simulations, you
can see it bobble and they merge
together. They make one bigger black
hole. And then it radiates in the
gravitational waves. It radiates away
all those imperfections and it settles
down to one quscent perfectly silent
black hole that's spinning. Beautiful
stuff. And it emits E= MC² energy. So
the mass of the final black hole will be
less than the sum of the two starter
black holes. And that energy is radiated
away in this ringing of spaceime. It's
really important to emphasize that it's
not light. None of this has to do
literally with light that we can detect
with normal things that detect light.
X-rays form of light. Gamma rays are a
form of light. Infrared, optical, all
this whole electromagnetic spectrum.
None of it is emitted as light. It's
completely dark. It's only emitted in
the rippling of the shape of space. A
lot of times it's likened closer to
sound. Technically, we've kind of
argued. I mean, I haven't done an
anatomical calculation, but if you're
near enough to two colliding black
holes, they actually ring spaceime in
the human auditory range. The frequency
is actually in the human auditory range
that the shape of space could squeeze
and stretch your eardrum even in vacuum.
And you could hear literally hear these
waves ringing.
The following is a conversation with
Jenna Levan, a theoretical physicist and
cosmologist specializing in black holes,
cosmology of extra dimensions, topology
of the universe, and gravitational waves
in spaceime. She has also written some
incredible books including how the
universe got its spots on the topic of
the shape and the size of the universe,
a mad man dreams of touring machines on
the topic of genius madness and the
limits of knowledge. Black hole blues
and other songs from outer space on the
topic of LIGO and the detection of
gravitational waves and black hole
survival guide all about black holes.
This was a fun and fascinating
conversation. This is a Lexman podcast.
To support it, please check out our
sponsors in the description. And now,
dear friends, here's Jenna 11. I should
say that you sent me a message about not
starting early in the morning, and that
made me feel like we're kindred spirits.
You wrote to me, "When the great
physicist Sydney Coleman was asked to
attend a 9:00 a.m. meeting, his reply
was, "I can't stay up that late." Yeah.
So, classic. Sydney was beloved. I think
all the best thoughts, honestly, maybe
the worst thoughts, too, are all come at
night. There's something There's
something about the night. Maybe it's
the silence. Maybe it's the peace all
around. Maybe it's the darkness and you
just
you could be with yourself and you could
think deeply. I feel like there's stolen
hours in the middle of the night because
it's not busy. Your gadgets aren't
pinging. There's really no pressure to
do anything but I'm off and awake in the
middle of the night and so it's sort of
like these extra hours of the day. I
think we were exchanging messages at 4
in the morning. Okay. So in that way,
many other ways were kindred spirits. M.
So, let's go in the one of the coolest
objects in the universe, black holes.
What are they? And maybe even a good way
to start is to talk about how are they
formed?
Yeah. In a way, people often confuse how
they're formed with the concept of the
black hole in the first place. So when
black holes were first proposed,
Einstein was very surprised that such a
solution could be found so quickly but
really thought nature would protect us
from their formation. And then nature
thinks of a way nature thinks of a way
to make these crazy objects which is to
kill off a few stars. But then I think
that there's a confusion that dead
stars, these very very massive stars
that die are synonymous with the
phenomenon of black hole. And it's
really not the case. Black holes are
more general and more fundamental than
just the death state of a star. But even
the history of how people realize that
stars could form black holes is is is
quite fascinating because the entire
idea really just started as a thought
experiment. And if you think of it's
1915 1916 when Einstein fully describes
relativity in a way that's the canonical
formulation. It was a lot of changing
back and forth before then. And it's
World War I and he gets a message from
the Eastern Front from a friend of his,
Carl Shortfield, who's who solved
Einstein's equations, you know, between
sitting in the trenches and like cannon
fire. Um, it was joked that he was
calculating ballistic trajectories. He's
also perusing the proceedings of the
Prussian Academy of Sciences as you do.
and he was an astronomer um who had
enlisted in his 40s and he finds this
really remarkable solution to Einstein's
equations and it's the first exact
solution. He doesn't call it a black
hole. It's not called a black hole for
decades. But what I love about what
Schwarz shield did is it's a thought
experiment. It's not about observations.
It's not about making these things in
nature. Um it's really just about the
idea. He sets up this completely
untenable situation. and he says,
"Imagine I crush all the mass of a star
to a point." Don't ask how that's done
because that's really absurd. Um, but
let's just pretend and let's just
imagine that that that's a scenario. And
then he wants to decide what happens to
spacetime if I set up this confounding
but somehow very simple scenario. And
really what Einstein's equations were
were telling everybody at the time was
that matter and energy curve space and
time and then curved spacetime tells
matter and energy how to fall once the
spacetime shaped. So he finds this
beautiful solution and the most amazing
thing about a solution is he finds this
demarcation which is the event horizon
which is the region beyond which not
even light can escape. And if you were
to ask me today all these
decass crushed to a point. The black
hole is the event horizon. The event
horizon is really just a point in
spaceime or or a region in spaceime.
It's actually in this case a surface in
spaceime. And it marks uh a separation
in events which is why it's called an
event horizon. Everything outside is
causally separated from the inside in so
far as what's inside the event horizon
can't affect events outside. What's
outside can affect events inside. I can
throw a probe into a black hole and
cause something to happen on the inside.
But the opposite isn't true. Somebody
who fell in can't send a probe out. And
this oneway aspect really is what's
profound about the black hole.
Um, sometimes we talk about the black
holes being nothing because at the event
horizon there's really nothing there.
Uh, sometimes when we when we think
about black holes, we want to imagine a
really dense dead star. But if you go up
to the event horizon, it's an empty
region of spaceime. It's it's more of a
place than it is a thing. And Einstein
found this fascinating. He helped get
the work published, but he really didn't
think these would form in nature. I
doubt Carl Schwarz shield did either. Um
I think they thought they were uh
solving theoretical mathematical
problems. Um but not describing this
what turned out to be the end state of
gravitational collapse. And maybe the
purpose of the thought experiment was to
find the limitations of the theory. So
you you find the most extreme versions
in order to understand where it breaks
down. Yeah. And it just so happens in
this case that might actually predict
these extreme kinds of objects. It does
both. So it also describes the sun from
far away. So the same solution does a
great job helping us understand the
Earth's orbit around the sun. It's
incredible. Does a great job. It's
almost overkill. You don't really need
to be that precise as relativity. Um,
and yes, it predicts the phenomenon of
black holes, but doesn't really explain
how nature would form them. But then it
also on top of that does signal the
breakdown of the theory. I mean, you're
quite right about that. It actually
says, "Oh, man." But you you go all the
way towards the center and yeah, this
doesn't sound right anymore. Um,
sometimes I liken it to, you know, it's
like a dying man marking in the dirt
that something's gone wrong here, right?
it it it's signaling that that there's
some culprit there's something wrong in
the theory and um and even Roger Penrose
who did this general work trying to
understand
uh the formation of black holes from
gravitational collapse he thought oh
yeah there's a singularity that's
inevitable it's in every there's no way
around it once you form a black hole but
he said this is probably just a
shortcoming of the fact that we've
forgotten to include quantum mechanics
and that when we do we'll understand
this um differently. So according to him
the closer you get to the singularity
the more quantum mechanics comes into
play and therefore there is no
singularity there's something else. I
think everybody would say that. I think
everybody would say the closer you get
to the singularity for sure you have to
include quantum mechanics. You just
can't consistently talk about magnifying
such small scales, having such enormous
uh ruptures and and curvatures and
energy scales and not include quantum
mechanics that that's just inconsistent
with the world as we understand it. So
you've described the brainbreaking idea
that a black hole is
uh not so much a super dense matter as
it's sometimes described, but it's more
akin to, you know, a region of space
time, but even more so just nothing.
Yeah, it's nothing. That that's a thing
you seem to like to say. I do I do like
to say that black holes are no thing.
They're nothing. Okay. So what what what
does that mean? That's that's what I
mean. That's the more profound aspect of
the black hole. So you asked originally
um how do they form? And I think that
that that even when you try to form them
in messy astrophysical systems, there's
still nothing at the end of the day left
behind. And um this was a very big
surprise. Even though Einstein accepted
that this was a true prediction, he
didn't think that that they'd be made.
And it was quite astounding that that
people like Oppenheimer actually it's
probably Oenheimer's most important
theoretical work um who are thinking
about nuclear physics and quantum
mechanics but in the context of these
kind of utopian questions why do stars
shine um why is the sun radiant and hot
and this amazing source of light and it
was people like Oenheimer who began to
ask the question well could stars
collapse to form black holes Could they
become so dense that uh eventually not
even light would escape? And that's why
I think people think that black holes
are these dense objects. That's often
how it's described. But actually what
happens these very massive stars,
they're burning thermonuclear fuel. You
know, they're earthfuls of thermonuclear
fuel. They're burning um and emitting
energy in E= MC² energy. So it's fusing.
It's a fusion bomb. It's a constantly
going thermonuclear bomb. And um
eventually it's going to run out of
fuel. It's going to run out of hydrogen,
helium, stuff to fuse. It hits an iron
core. Iron to go past iron with fusion
is actually energetically expensive. So
it's no longer going to do that so
easily. So suddenly it's run out of
fuel. And if the star is very very very
massive, much more massive than our sun,
maybe 20, 30 times the mass of our sun,
it'll collapse under its own weight. And
that collapse is incredibly fast and
dramatic and it creates a shock wave. So
that's the supernova explosion. So a lot
of these they rebound because once they
crunch they've reached a new critical uh
capacity where they can reignite to
higher elements, heavier elements and
that sets off a bomb essentially. So,
the star explodes helpfully because
that's why you and I are here because
stars send their material back out into
space and you and I get to be made of
carbon and oxygen and all this good
stuff. We're not just
hydrogen. So, the suns do that for us.
And then what's left sometimes ends at a
neutron star, which is a very cool
object, very fascinating object, super
dense, uh, but bigger than a black hole,
meaning it's it's it's not compact
enough to become a black hole. It's an
actual thing. A neutron star is a real
thing. It's like a giant neutron.
Literally, electrons get jammed into the
protons and make this giant nucleus and
this superconducting matter. Very
strange, amazing objects. But if it's
heavier than that the core and that's
you know heavier than twice the mass of
the sun um it will become a black hole
and Oenheimer was wrote this beautiful
paper in
1939 with his student uh saying that
they believed that the end state of
gravitational collapse is actually a
black hole. This is stunning and really
um a visionary conclusion. Now, the
paper is published the same day the
Nazis advance on Poland and so it does
not get a lot of fanfare in the
newspapers. Yeah, we think there's a lot
of drama today on social media. Imagine
that. Like here's a guy who predicts how
actually in nature would be the
formation of this most radical of object
that broke even Einstein's brain while
one of the most evil if not the most
evil humans in history starting a uh the
first steps of a global war. What I also
love about that lesson is how agnostic
science is because he was asking these
utopian questions as were other people
of the time about the nuclear physics
and stars. You might know this play
Copenhagen by Michael Fra. There's this
line that he attributes to Boore and
Boore was the great thinker of early
foundations of quantum mechanics, Danish
physicist, where Boore says to his wife,
"Nobody's thought of a way to kill
people using quantum mechanics." Now, of
course, then there's the nuclear bomb.
And what I love about this was the
pressure scientists were under to do
something with this nuclear physics and
and to enter this race over um a nuclear
weapon. But really at the same time,
1939 really uh Oenheimer's thinking
about black holes. There's a there's
even a small line in Chris Nolan's film.
It's very hard to catch. There's a
reference to it in the film where he
they're sort of joking well I guess
nobody's going to pay attention to your
paper now you know because uh because of
the Nazi advance on Poland that's the
other remarkable thing about Oppenheimer
is he's also a central figure in the
construction of the bomb right so it's
theory and experiment clashing together
with the geopolitics exactly so of
course Oppenheimer now known as the
father of the atomic bomb um he talks
about destroyers of worlds um But it's
the same technology and that's what I
mean by science is agnostic, right? It's
the same technology overcoming a
critical mass um igniting thermonuclear
fusion. Eventually there was a fision
the original bomb was a fision bomb and
fision was first shown by Le Mitner who
showed that a certain uranium when you
bombarded it with protons broke into
smaller pieces that were less than the
uranium. Right? So some of that mass
that E= MC² energy had escaped and it
was the first kind of concrete
demonstration of this Einstein's most
famous equation. So all of this comes
together but the story of um they still
weren't called black holes. This is
1939 and they had these very long-winded
ways of describing the end state the
catastrophic end state of gravitational
collapse. But what you have to imagine
is as this star collapses. So now, so
what's the sun? The sun's a million and
a half kilometers across. So imagine a
star much bigger than the sun. Much
bigger radius. And it's so heavy it
collapses. It supernovas. What's left is
still maybe 10 times the mass of the
sun. Just what's left in that core. And
it continues to collapse. And when that
reaches about 60 kilometers across, like
just imagine 10 times the mass of the
sun citys sized. That is a really dense
object. And now the black hole
essentially has begun to form. Meaning
the curve in spaceime is so tremendous
that not even light can escape. The
event horizon forms. But the event
horizon is almost imprinted on the
spacetime because the star can't sit
there in that dense state any more than
it can race outward at the speed of
light because even light is forced to
rain inwards. So the star continues to
fall and that's the magic part. The star
leaves the event horizon behind and it
continues to fall and it falls into the
interior of the black hole. Where it
goes, nobody really knows. But it's gone
from sight. It goes
dark. There's this quote by John Wheeler
who's like granddaddy of American
relativity and he has a line that's
something to the effect. Um, the star
like the Cheshire cat fades from view.
One leaves behind only its grin, the
other only its gravitational attraction.
And he was giving a lecture. It's
actually above Tom's restaurant, you
know, from Seinfeld near Colombia in New
York. Nice. There was a a place or there
still is a place there where people were
giving lectures about astrophysics. And
it's 1967.
Wheeler is exhaustively saying this
loaded term, the end state of
catastrophic gravitational collapse. And
rumor is that someone shouts from the
back row, well, how about black hole?
And um apparently he then foists this
term on the world. Wheelerhead way of
doing that. Well, I love terms like
that. Big bang, black hole. There's some
I mean, it's just pointing out the
elephant in the room and calling it an
elephant. It is a black hole. That's a
pretty uh accurate and deep description.
I just wanted to point out that the just
looking for the first time at a 1939
paper from Oppenheimer. It's like two
page. It's like three pages. Oh yeah,
it's gorgeous. The simplicity of some of
these that's so gangster. Just
revolutionize all of physics with this
with you know Einstein did that multiple
times in a single year. Mhm. When all
thermonuclear sources of energy are
exhausted, a sufficiently heavy star
will collapse. That's an opener. Mhm.
Unless fision due to rotation, the
radiation of mass or the blowing off of
mass by radiation reduce the stars mass
to orders of that of the sun, this
contraction will continue indefinitely.
And it goes on that way. Yeah. Now, I
have to say that Wheeler, who actually
coins the term black hole, uh gives
Oenheimer quite a terrible time about
this. He thinks he's wrong. and they
entered what has sometimes been
described as kind of a bitter I don't
know if you would actually say feud but
there were bad feelings and um Wheeler
actually spent decades uh saying
Oenheimer was wrong and eventually with
his computer work that early work that
Wheeler was doing with computers when he
was also trying to understand nuclear
weapons and in peace time world found
themselves returning again to these
astrophysical questions
uh decided that actually Oenheimer had
been right. He thought it was too
simplistic, too idealized a setup that
they had used and that if you you looked
at something that was more realistic and
more complicated that it it just simply
it just would go away. And in fact, he
he draws the opposite conclusion.
There's a story that Oppenheimer was
sitting outside of the auditorium when
Wheeler was coming forth with his
declaration that in fact black holes
were the likely end state of
gravitational collapse for very very
heavy stars and um when asked about it
Oppenheimer sort of said well I've moved
on to other things because you've
written in many places about the human
beings behind the science I have to ask
you about this about nuclear weapons
where is the greatest of physicists
coming together to create this most
terrifying and powerful of a technology.
And now I get to talk to world leaders
for whom this technology is part of the
tools that is used perhaps implicitly on
the chessboard of geopolitics. What what
can you say as a person who's a
physicist and who have studied the
physicists and written about the
physicists the humans behind this about
this moment in human history when
physicists came together and created
this weapon that's powerful enough to
destroy all of human civilization. I
think it's an
excruciating moment in in the history of
science and
um people talk about Heisenberg who
stayed in Germany and and uh worked for
the Nazis in their own attempt to build
the bomb. There was this kind of hopeful
talk that maybe Heisenberg had
intentionally derailed the nuclear
weapons program. But I think that's been
largely discredited that he would have
made the bomb could he had he not made
some really kind of simple errors in his
original estimates about how much
material would be required or how they
would get over the energy barriers. And
that's a terrifying thought.
Um, I I don't know that any of us can
really put ourselves in that position of
imagining that we're faced with that
quandry, having to take the initiative
to participate in thinking of a way that
quantum mechanics can kill people and
then making the bomb. I think
overwhelmingly physicists today feel we
should not continue in the proliferation
of nuclear weapons. Very few um
theoretical physicists want to see this
continue. that moment in history, the
Soviet Union had incredible scientists.
Nazi Germany had incredible scientists
and the United States had incredible
scientists. And it's very easy to
imagine that one of those three would
have created the bomb first, not the
United States. And how different would
the world be? The game theory of that I
think say the probability is 33% that it
was the United States. If the Soviet
Union had the
bomb, I think I think they would have
used it in a much more terrifying way in
the in the European theater and maybe
turn on the United States. And obviously
with Hitler, he would have used it. I
think there's no question he would have
used it to to to kill hundreds of
millions of people. In the game theory
version, this was the least harmful
outcome. Yes. Yes. But there is no
outcome with no bomb that that any game
theorist would uh I think would play.
But I I think if we just remove the
geopolitics and the ideology and the
evil dictators,
all of those people are just
scientists. I think they don't
necessarily even think about the
ideology. And it's a it's a it's a deep
lesson about the connection between
great science and the annoying sometimes
evil politicians that use that science
for means that are either
good or bad. Mhm. And the scientists
perhaps don't boy do they even have
control of how that science is used.
It's hard. They don't have control.
Right. once it's once it's made, it's no
longer scientific reasoning that
dictates the use or um it's restraint.
But I will say that I do believe that it
wasn't a 30 one-third down the line
because America was different and I
think that's something we have to think
about right now in this particular
climate. So many scientists fled here.
They fled to here.
Americans weren't fleeing to Nazi
Germany. they came here and and they
were motivated um by uh it's more than a
patriotism, you know, it was um I mean
it was a patriotism obviously, but it
was sort of more than that. It was
really understanding the threat of
Europe, uh what was going on in Europe
and um and what that life, how quickly
it turned, how quickly this freespirited
Berlin culture, you know, was suddenly
in this repressive and terrifying uh
regime. So, I think that it was a much
higher chance that it happened here in
America. Yeah. And there's something
about the American system, the you know
it's cliche to say but the freedom all
the different individual freedoms that
enable a very vibrant at its best a very
vibrant scientific community and that's
really exciting absolutely to scientists
and it's very valuable to ma maintain
that right the the vibrancy of the
debate of the funding those mechanisms
absolutely the world flocked here and
that won't be the case if we no longer
have intellectual freedom yeah there's
there's something interesting to think
about the tension the cold war between
China and the United States in the 21st
century you know some of those same
questions some of those ideas will rise
up again and we want to make sure that
um there's a vibrant free exchange of
scientific ideas I believe most Nobel
prizes come from the United States right
oh yeah I don't have the number but I
disproportionately so disproportionately
so in fact a lot of them from particle
physics came from the Bronx
[Laughter]
and they were European immigrants. How
do you explain this? Fled Europe um
precisely because of the geopolitics
we're describing. Yeah. And so instead
of being Nobel Prize winners from the
Soviet Union or from the Eastern Block,
they were from the Bronx.
And that's the thing you write about and
we'll return to time and time again that
you know science is done by humans. And
some of those humans are fascinating.
There's tensions. There's battles.
There's some are loners. Some are great
collaborators. Some are tormented, some
are easygoing, all this kind of stuff.
And that's the beautiful thing about it.
We forget sometimes is it's humans and
humans are messy and complicated and
beautiful and all of that. Yeah. Uh so
what were we talking about? Oh, the star
is collapsing.
Okay. So can we just return to the
collapse of a star that forms a black
hole? At which point does the super
dense thing become nothing? if we can
just like linger on this concept. Yeah.
So if I were falling into a black hole
and I I I tried really fast right as I
crossed this empty region but this
demarcation I happened to know where it
was. I calculated because there's no
line there. There's no sign that it's
there. There's no signpost. Um I could
emit a little light pulse and try to
send it outward exactly at the event
horizon. So it's racing outward at the
speed of light. It can hover there
because from my perspective, it's very
strange. The spaceime is like a
waterfall raining in and I'm being
dragged in with that waterfall. I can't
stop at the event horizon. It comes, it
goes. It's behind me really quickly.
That light beam can try to sit there
because it's like it's like a fish
swimming against the Niagara, you know,
swimming against the waterfall. It's
like stuck there. But it's like stuck
there. Um, and so that's one way you
could have a little signpost. You know,
if you fly by, you think it's moving at
the speed of light. It flies past you at
the speed of light, but it's sitting
right there at the event horizon. So,
you're falling back, cross the event
horizon. Right at that point, you shoot
outwards a photon. Yes. And it's just
stuck there. It just gets stuck there.
Now, it's very unstable. So, the star
can't sit there is the point. It It just
can't. So, it rains inward with this
waterfall. But from the outside, all we
should ever really care about is the
event horizon because I can't know what
happens to it. It could be pure matter
and antimatter thrown together which
annihilates into photons on the inside
and loses all its mass into the energy
of light. Won't matter to me because I
can't know anything about what happened
on the inside. Okay. Can we just like
linger on this? So what models do we
have about what happens on the inside of
the black hole at that moment? So I
guess that one of the intuitions, one of
the big reminders that you're giving to
us is like, hey, we know very
little about what can happen on the
inside of a black hole. And that's why
we have to be careful about making it's
better to think about the black hole as
an event horizon. But what can we know
and what do we know about the physics of
of space time inside the black hole? I
don't mind being incautious about
thinking about what the math tells us.
So I'm not such
a an observer. I'm very theoretical in
my work. It's really pen on paper a lot.
Um these are thought experiments that I
think we we can perform and contemplate.
Um whether or not we'll ever know is
another question. And um so one of the
most beautiful things that we suspect
happens on the inside of a black hole is
that space and time in some sense swap
places. So while I'm on the outside of
the black hole, let's say I'm in a nice
comfortable space station. This black
hole is maybe 10 times the mass of the
sun, 60 kilometers across. I could be a
100 kilometers out. That's very, very
close. Orbiting quite safely. No big
deal. You know, hanging out. Uh I don't
bug the black hole. Black hole doesn't
bug me. It won't suck me up like a
vacuum or anything crazy. But uh some my
my astronaut friend jumps in.
Um, as they cross the event horizon,
what I'm calling space, I'm looking on
the outside at this spherical shadow of
the black hole cast by maybe light
around it. It's a shadow because
everything gets too close, falls in.
It's just this um uh just contrast
against a bright sky. I think, oh,
there's a center of a sphere and in the
center of the sphere is the singularity.
It's a point in space from my
perspective, but from the perspective of
the astronaut who falls in, it's
actually a point in
time. So their notions of space and time
have rotated so completely that what I'm
calling a direction in space towards the
center of the black hole, like the
center of a physical sphere, they're
going to tell me, well, they can't tell
me, but they're going to come to the
conclusion, oh no, that's not a location
in space. That's a location in time. In
other words, the singularity ends up in
their future and they can no more avoid
the singularity than they can avoid time
coming their way. So there's no
shenanigans you can do once you're
inside the black hole to try to skirt it
the singularity. You can't set yourself
up in orbit around it. You can't try to
fire rockets and stay away from it
because it's in your future and there's
an inevitable moment when you will hit
it. Usually for a stellar mass black
hole, we think it's micros secondsonds.
Micros secondsonds to get from the event
horizon to the to the singularity. To
the singularity. Oh boy. Oh boy. So
that's describing from the your
astronaut friend's perspective. Yes.
From their perspective, the
singularities in their future. But from
your perspective, what do you see when
your friend falls into the black hole
and you're chilling outside and
watching? So, one way to think about
this um is to is to think that as you're
approaching the black hole, the
astronaut's spaceime is rotating
relative to your spacetime. So, let's
say right now my left is your right.
We're not shocked by the fact that
there's this relativity in left and
right. It's completely understood. And I
can perform a spatial rotation to align
my left with your left. Right now I've
completely rotated left out. Right. Um
if I just want to draw a a a kind of uh
compass diagram, not a compass diagram,
but you know at the top of maps there's
a northsoutheast west. But now time is
up down and one direction of space is
let's say east west. As you approach the
black hole it's as though you're
rotating in spaceime is one way of
thinking about it. So what is the effect
of that? The effect of that is as this
astronaut gets closer and closer to the
event
horizon, part of their space is rotated
into my time and part of their time is
rotated into my space. So in other
words, their clocks seem to be less
aligned with my time. And the overall
effect is that their time seems to
dilate. the spacing between ticks on the
clock of their watch, let's say, um on
the on the face of their watch, uh is is
elongated, dilated relative to mine. And
it seems to me that their watches are
running slowly, even though they were
made in the same factory as mine. They
were both synchronized beautifully and
they're excellent Swiss watches. Um, it
seems as though time is elapsing more
slowly for my
companion and uh likewise for them it
seems like mine's going really
fast. So years could elapse in my space
station. My plants come and go. They
die. I age faster. I've got gray hair.
Um, and they're falling in and it's been
minutes in their frame of reference.
Um, flowers in their little rocket ship
haven't rotted. They don't have gray
hair. Their biological clocks have
slowown down relative to ours.
Eventually at the event horizon, it's so
extreme. It's so slow. It's as though
their clocks have stopped altogether
from my point of view. And that's to say
that it's as though their time is
completely rotated into my space. And
this is connected with the idea that
inside the black hole space and time
have switched places.
Um, so I might see them hover there for
millennia. Other astronauts could be
born on my space station. Generations
could be populated there watching this
poor astronaut never fall in. So
basically the time almost comes to a
standstill, but we still they do fall
in, right? They do fall in eventually.
Now that's because they have some mass
of their own. Yeah. So they're not a
perfectly light particle and so they
deform the event horizon a little bit.
You'll actually see the event horizon
bobble and absorb the astronaut. So in
some finite time the astronaut will
actually fall in. So it's a it's like
this weird space-time bubble that we
have around us. Mhm. And then there's a
very big space-time curvature bubble
thing from the black hole and they
there's a nice swirly type situation
going on. That's how you get sucked up.
Yeah. So if you're a perfect like uh
infinitely small particle, you would
just be take longer and longer and
probably just be stuck there or
something. But no, there's quantum
mechanics. Mhm. Eventually you'll fall
in there. Any perturbation will only go
one way. It's unstable in one direction.
In one direction only. Um, but it's it's
really important to remember that from
the point of view of the astronaut, not
much time has passed at all. You just
sail right across as far as you're
concerned and nothing dramatic happens
here. You might not even realize you've
come to the event horizon. You you might
not even realize you've crossed the
event horizon because it's there's
nothing there. Right? This is an empty
region of spaceime. There's no marker to
tell you you've reached this very
dangerous point of no return. You can
fire your rockets like hell when you're
on the outside and maybe even escape,
right? But once you get to that point,
there's no amount of energy. All the
energy in the universe will not save you
from uh this demise. You know, there's
different size black holes. Mhm. And
maybe can we talk about the experience
that you have falling into a black hole
depending on what the size of the black
hole is? Yeah. cuz um as I understand if
the the the bigger it
is, the less drastic the experience of
falling into it. Yeah, that might
surprise people. The bigger it is, the
less noticeable it is that you've you've
crossed the event horizon. One way to
think about it is um curvature is less
noticeable the bigger it is. So, if I'm
standing on a basketball, I'm very aware
I'm I'm balancing on a curved surface. I
my two feet are in different locations
and I really notice. But on the Earth,
you actually have to be kind of clever
to deduce that the Earth is curved. The
bigger the planet, the less you're going
to notice the curvature. Um the the
global curvature. And it's the same
thing with a black hole, a huge huge
black hole. It just is kind of feels
like just flat. You don't really notice.
I'm trying to figure out how the phys
because if you don't notice and there's
nothing there but the physics is weird
in your frame of reference.
No. Well, so another cool thing. So I'd
like to dispel myths.
Yeah. Do you need a
minute? You're holding your head.
There's a sense like you you should be
able to know when you're inside of a
black hole when you've crossed the event
horizon. But no, from your frame of
reference, you might not be able to
know. Yeah, at first at least, you might
not realize what's happened. There are
some hints. For instance, black holes
are dark from the outside, but they're
not necessarily dark on the inside. So
this is uh a kind of fascinating that
your experience could be that it's quite
bright inside the black hole because all
the light from the galaxy can be shining
in behind you and it's focusing down
because you're all approaching this
really focused region in the interior.
And so you actually see a bright white
flash of light as you approach the
singularity. Um, you know, I kind of uh
I joke that it's a, you know, it's like
a near-death experience. You see the
light at the end of the tunnel. So, you
would see millennia pass on Earth. You
could see the evolution of um the entire
galaxy, you know, one big bright flash
of light. So, it's like a near-death
experience, but it's a definitely a
total death experience. It goes pretty
fast. But you looking out, you looking
out, everything's going super fast.
Yeah. the
clocks um on the earth on the space
station seem to be progressing very
rapidly relative to yours. The light can
catch up to you and you get this bright
beam of light as you see the evolution
of the galaxy unfold and
um I mean it sort of depends on the size
of the black hole and how long you have
to hang around. The bigger the black
hole the longer it takes you to expire
in the center. Obviously the human uh
sensory system we're not able to process
that information correctly right it
would be a microcond in a right that
would be too fast. Yeah but it would be
wow it' be so cool to get that
information but a big black hole you
could actually you know hang around for
some months. So yeah what's uh how are
small black holes versus super massive
uh black holes formed just so people can
kind of load that in. Are they are they
all is it always a star? No. So this is
also why it's important to think of
black holes more
abstractly. They are something very
profound in the universe and there are
probably multiple ways to make black
holes. Um making them with stars is most
plentiful. There could be hundreds of
millions maybe even a billion black
holes in our Milky Way galaxy alone.
that many stars. It's only about 1% of
stars that will um end their lives in in
in a death state that is a black hole.
But we now see and this was really quite
a surprise that there are super massive
black holes. They're billions or even
hundreds of billions of times the mass
of the sun and um uh millions to to tens
of billions maybe even hundreds of
billions. So extremely massive. We don't
think that the universe has had enough
time to make them from stars that just
merge. We know that two black holes can
merge and make a bigger black hole and
then those can merge and make a bigger
black hole. We don't think there's been
enough time for that. So, it's suspected
that they're formed very early, maybe
even a hundred few hundred million years
after the big bang and that they're
formed directly by collapsing out of
primordial stuff. Mhm. that there's a
direct collapse right into the black
hole. So like in the in the very early
universe, these are primordial black
holes from the stars. Not quite Wait,
how how do you get from that soup black
holes right away, right? So it's odd,
but it's weirdly easier to make a big
black hole out of something that's just
the density of air if it's really really
as big as what we're talking about. So,
in some sense, if they're just allowed
to directly collapse very early in the
universe's history, they can do that
more easily. Um, and it's so much so
that we think that there's one of these
super massive black holes in the center
of every galaxy. So, they're not rare
and we know where they are. They're in
the nuclei of galaxies. So, they're
bound to the very early formation of
entire galaxies in um in a really
surprising and deeply connected way. I
wonder if the like the chicken or the
egg is it uh like how critical how
essential are the super massive black
holes to the formation of galaxies?
Yeah, I mean it's ongoing, right? It's
ongoing. Which came first, the black
hole or the galaxy? Um probably um big
early stars which were just made out of
hydrogen and helium from the big bang.
Um there wasn't anything else, not much
of anything else. um those early stars
were forming and then maybe the black
holes and kind of the galaxies were like
these gassy clouds around them. Um but
there's probably a deep relationship
between the black hole powering jets,
these jets blowing material out of the
galaxy that that shaped galaxies maybe
kind of curbed their growth. Um and so I
think the mechanisms are still are still
ongoing attempts to understand exactly
the ordering of these things. Can we get
back to spacetime? Just going back to
the beginning of the 20th century. How
do you imagine spacetime? How do we as
human beings supposed to visualize and
think about spacetime where you know
time is just another dimension in this
4D space that combines space and time?
Because we've been talking about
morphing in all kinds of different ways.
is a curvature of spacetime like how do
you how are we supposed to conceive of
it? How do you think of it? Yeah, time
is just another dimension. There are
different ways we can think about it. We
can
imagine drawing a map of space and
treating time as another direction in
that
map. But we're limited because as
three-dimensional beings, we can't
really draw four dimensions, which is
what I'd require. three spatial because
I'm pretty sure there's at least three.
I think there's probably more, but um
I'm happy just talking about the large
dimensions, the three we see up, down,
right, east, west, uh north, south,
three spatial dimensions and time is the
fourth. Nobody can really visualize it.
Um but we know mathematically how to
unpack it on paper. I can mathematically
suppress one of the spatial dimensions
and then I can draw it pretty well. Now
the problem is that we'd call it a
ukitian spacetime. A uklitian spacetime
is when all the dimensions are
orthogonal and are treated equally. Time
is not another ukitian dimension. It's
actually a manowskian spacetime. But it
means that the spacetime, we're
misrepresenting it when we draw it, but
we're misrepresenting it in a way that
we deeply understand. I can give you an
example. The Earth, I can project onto a
flat sheet of paper. I am now
misrepresenting a map of the Earth. And
I know that, but I understand the rules
for how to add distances on this
misrepresentation because the Earth is
not a flat sheet of paper. It's a
sphere. And um and as long as I
understand the rules for how I get from
the north pole to the south pole that
I'm moving along really a great arc and
I understand that the distance is not
the distance I would measure on a flat
sheet of paper then I can do a really
great job with a map and understanding
the rules of addition multiplication and
the geometry is not the geometry of a
flat sheet of paper. I can do the same
thing with spacetime. I can draw it on a
flat sheet of paper but I know that it's
not actually a flat uklidian space. And
so my rules for measuring distances are
different than the rules I would use
that for instance cartisian rules of
geometry. I I would know to use the
correct rules for manovski spacetime and
and that will allow me to to to to
calculate how long uh time has elapsed
which is now a kind of a length a
space-time length on my map um between
two relative observers. and I will get
the correct answer. Um but only if I use
these different rules. So then what does
according to general relativity does
uh objects with mass due to the
spacetime? Right. Exactly. So Einstein
struggled for this completely general
theory not a specific solution like a
black hole or an expanding spaceime or
galaxies make lenses or those are all
solutions. That's why what he did was so
enormous. It's an entire paradigm that
says over here is matter and energy. I'm
going to call that the right hand side
of the equation. Everything on the right
hand side of Einstein's equations is how
matter and energy are distributed in
spaceime. On the left hand side tells
you how space and time deform in
response to that matter and energy. And
it can be impossible to solve some of
those equations. What was so amazing
about what Shell did is he found this
very elegant simple solution within like
a month of reading um this final
formulation. But Einstein didn't go
through and try to find all the
solutions. He sort of gave it to us,
right? He shared this and then lots of
people since have been scrambling to try
to ah I can predict the curvature of the
spaceime if I tell you how the matter
and energy is laid out. If it's all
compact in a spherical system like a sun
or even a black hole, I can understand
the curves in the spaceime around it. I
can solve for the for the shape of the
spacetime. I can also say, well, what if
the universe is full of gas or light and
it's all kind of uniform everywhere and
I'll find a different and equally
surprising solution, which is that the
universe would
expand. In response to that, that it's
not static, that the distances between
galaxies would grow. This was a huge
surprise to Einstein. Um, so all of
these consequences of his theory, you
know, came with
revelations that were not at all obvious
when he first wrote down um the general
theory and he was afraid to take the
consequences of that theory seriously,
which is aen the theory itself in its
scope and grandeur and power
is scary. So I can understand. Then
there's, you know, the the edges of the
theory where it falls apart. The
consequences of the theory that are
extreme, it's hard to take seriously. So
you can sort of empathize. Yeah. He very
much resisted the expansion. So if you
think about 1905 when he's writing these
sequence of unbelievable papers as a
25year-old who can't get a job, you
know, as a physicist and he writes all
of these remarkable papers on relativity
and quantum mechanics. Um and then even
in
191516 he does not know that there are
other galaxies out there. This this was
not known. People had mused about it. Um
there were these kind of smudges on the
sky that
people contemplated what if there are
other island universes. You know going
back to Kant thought about this. But it
wasn't until Hubble it really wasn't
until the late 20s um that it's
confirmed that there are other galaxies.
Wow. Yeah. He didn't
obviously there's so much we think of
now that he didn't think of. So there's
no big bang
static universe. But these are all
connected. Wow. Yeah. So he's operating
on very little information. Very little
information. That's absolutely true.
Actually, one of the things I like to
point out is the idea of relativity was
foisted on people in this kind of
cultural way. But there's many ways in
which you could call it a theory of
absolutism. And um the way Einstein got
there with so little information um is
by adhering to certain very strict
absolutes like the
absolute limit of the speed of light and
the absolute constancy of the speed of
light which was completely bizarre when
it was first uh discovered. really that
was observed through experiments trying
to figure out
um you know what would the relative
speed of light be? It's the only really
only massless particles have this
property that they have an absolute
speed and if you think about it it's
incredibly strange. Yeah, it's really
strange. Incredibly strange. And so so
from from a theoretical perspective he
he's he takes that seriously. He takes
it very seriously and everyone else is
trying to come up with models to make it
go away. Um to make uh the speed of
light be a little bit more reasonable
like everything else in the universe. Um
you know if I run at a car, two cars
coming at each other, they're coming at
each other faster than if one of them
stops. It's really a basic observation
of reality right here. This is saying
that if I'm racing at a light beam um
and you're standing still relative to
the source, uh we'll measure the same
exact speed of light. Very strange. And
he gets to relativity by saying, well,
what's speed? Speed is distance. It's
space over time. It's how far you
travel. Um it's the space you travel in
a certain duration of time. And he said,
"Well, I bet something must be wrong
then with space and time." So this is an
enormous leap. He's willing to give up
the absolute character of space and time
in favor of keeping the speed of light
constant. How was he able to
intuitit a world of curved spaceime?
Like I think it's like one of the most
special leaps in human history, right?
Cuz you're it's amazing. like it's very
very very difficult to make that kind of
leap. I I'll tell you it took me I think
a long time to I can't say this is how
he got there exactly. It's not as though
I studied the historical accounts of or
his description of his internal states.
This is more having learned the subject
how I try to tell people how to get
there in a few short steps. Um, one is
to start with the equivalence principle
which he called the happiest thought of
his
life. And the equivalence principle
comes pretty early on in his thinking.
And and um it starts with something like
this. Like right now I think I'm feeling
gravity because I'm sitting in this
chair and I feel the pressure of the
chair and it's stopping me from falling
and um lie down in a bed and I feel
heavy on the bed and I think of that as
gravity.
Ein has a beautiful ability to remove
all of these
extraneous factors, including atoms. So,
let's imagine instead that you're in an
elevator and you feel heavy on your feet
because the floor of the elevator is
resisting your fall, but I want to
remove the elevator. What does the
elevator have to do with fundamental
properties of gravity? So, I cut the
cable. Now, I'm falling, but the
elevator is falling at the same rate as
me. So now I'm floating in the elevator.
And if this happened to me, if I woke up
in this state of falling or floating in
the elevator, I might not know if I was
in empty space just floating
um or if I was falling around the earth.
There would actually equivalent
situations. I would not be able to tell
the difference. I'm actually when I get
rid of the elevator in this way by
cutting the cable, I'm actually
experiencing weightlessness.
And that weightlessness is the purest
experience of
gravity. And um and so this idea of
falling is actually fundamental. It's
how we talk about it all the time. The
earth is in a free fall around the sun.
It's actually falling. It's not firing
engines, right? It's just it's just
falling all the time, but it's just
cruising so fast. So actually Yeah. God,
you said so many profound things. So one
of them is really one of the ways to
experience
spaceime is to be falling. To be falling
that is the purest experience of
gravity. The experience of gravity uh
unfettered uninterrupted by
atoms is weightlessness.
Yeah. That observation no it has an
unhappy ending. the elevator story,
right? Because of atoms. Again, that's
the fault of the atoms in your body
interacting electromagnetically with the
crust of the earth or the bottom of the
building or whatever it is. Um, but this
period of freeall, so the first
observation is that that is the purest
experience of gravity. Now, I can
convince you that things follow along
curved paths because I could take uh,
you know, a pen and if I throw it, we
both know it's going to follow an arc
and it's going to follow an arc until
atoms interfere again and it hits the
ground. But while it's in freef fall
experiencing gravity at its purest, what
the Einsteinian description would say is
it is following the natural curve in
spaceime inscribed by the earth. So the
earth's mass and shape curves the paths
in space and then those curvatures tell
you how to fall, the paths along which
you should fall when you're falling
freely.
And so the Earth has found itself on a
free fall that happens to be a closed
circle, but it's it's actually falling.
The International Space Station uses
this principle all the time. They get
the space station up there and then they
turn off the engines. Can you imagine
how expensive it would be if they had to
fuel that thing at all times? Right.
They turn off the engines. They're just
falling. Yeah, they're falling. And
they're not that far up. Um there there
are certainly people sometimes say, "Oh,
they're so far away they don't feel
gravity." Oh, absolutely. If you stopped
the space station, it's going like
17,500 m an hour, something like that.
If you were to stop that, it would drop
like a stone right to the earth. So,
they're in a state of constant freefall
and they're falling along a curved path.
And that curved path is a result of
curving spacetime and that particular
curved path's calculated in such a way
that it curves onto itself. So, you're
orbiting, right? So it has to be
cruising at a certain speed. So once you
get it at that cruising speed, you turn
off the engines. But yeah, to be able to
visualize at the beginning of the 20th
century Mhm.
that not you know that free falling in
in in curved spaceime. Mhm. Boy, the
human mind is capable of things. I mean
some of that is
um constructing thought experiments that
collide with our understanding of
reality. Maybe in the collisions, in the
contradictions, you try to think of
extreme thought experiments that that uh
exacerbate that contradiction and see
like, okay, what is actually is there
another model that can incorporate this?
But to be able to do that, I mean, it's
it's kind of inspiring
because, you know, there's probably
another general relativity out there.
Yeah. in all not just in physics in all
lines of work in all scientific pursuits
there's certain theories where you're
like okay I just explained like a big
elephant in the room here that everybody
just kind of didn't even think about
there could be uh for stuff we know
about in physics there could be stuff
like that for the origin of life on
earth
everyone's like yeah okay everyone's
like in polite companies
Yeah. Yeah. Yeah. Yeah. Somehow it
started. Mhm. Right. Nobody knows. I
find it wild that that's so elusive.
Yeah. It's it's strange. And the lab
became strange that it's so elusive. I
think it's a general relativity thing.
There's going to be some thing. It's
going to involve aliens and wormholes
and and dimensions that we don't quite
understand or some some field that's
bigger than like it's possible, maybe
not. It's possible that it has it's a
field that is different that will feel
fundamentally different from chemistry
and biology it'll be maybe through
physics again maybe the key to the
origin of life is in physics and the
same there it's like a a weird neighbor
is consciousness. Mhm. It's like all
right a weird neighbor. Yeah. It's like
okay so we all know that life started on
Earth somehow. Mhm. Nobody knows how.
Mhm. We all know that we're
conscious. We have a subjective
experience of things. Nobody understands
that people have ideas and so on. But
it's such a dark sort of we're entering
a dark room where a bunch of people are
whispering about like, "Hey, what's in
this room?" But nobody nobody has a
effing clue. Mhm. So, and then somebody
comes along with a general relativity
kind of conception where like it
reconceives everything and you're like
ah it's like a watershed moment. Yeah.
Yeah. It's there and until we're living
in the mo we're living in a time until
that theory comes along and uh it'll be
obvious in retrospect, but right now
we're right. Well, this it was obvious
to no one that spacetime was curved, but
even Newton understood something wasn't
right. So, he knew there was something
missing. And I think that's always
fascinating when we're in a situation
where we're pressure testing our own
ideas. He did something remarkable,
Newton did, with his theory of gravity.
Just understanding that the same
phenomena was at work with the earth
around the sun as the apple falling from
the tree. That's insane. That's a huge
leap. Understanding that mass, inertial
mass, what makes something hard to push
around is the same thing that feels
gravity in at least in the Newtonian
picture in that simple way. Unbelievable
leap. Absolutely genius. But he didn't
like that the apple fell from the tree
even though the earth wasn't touching
it. Yeah, the action at a distance
thing. The action at a distance thing.
That is weird, too. Well, but that is a
really weird one. It's really weird. But
see, Einstein solves that. Relativity
solves that because it
says the Earth created the curve in
space. The apple wants to fall freely
along it. The problem is the trees in
the way. The tree is the problem. The
tree is actually accelerating the apple.
It's keeping it away from its natural
state of weightlessness in a
gravitational field. And as soon as the
tree lets go of it, the apple will
simply fall along the curve that exists.
I would I would love it if somebody went
back to Newton's time and told him all
this. Probably some like some like
hippie would be like it's a gravity is
just the curvature in space time, man. I
wonder if he would be able to I don't
think there's you know every idea has
its time. He might not he might not even
be able to load that in.
I I mean that sometimes even the
greatest geniuses I mean you can't like
you need too out of context. You need to
be standing on the shoulders of giants
and on the shoulders of those giants and
so on. I heard that Newton used that as
an unkind remark to his competitor Hook.
Oh no, the people talk even back
then. Trash talking.
This is one of the hilarious things
about humans in general, but scientists
too, like these huge minds. There's
these moments in history where you'll
see this in this in universities, but
everywhere else too. Like you have
gigantic minds obviously also coupled
with everybody has an ego and like
sometimes it's just the same soap opera
that played out amongst humans
everywhere else and so you're thinking
about the biggest cosmological objects
and forces and ideas and you're still
like jealous and right I know your your
office is bigger than my office. I know
this chair this or or maybe uh you got
married to this person that I was always
in love with the betrayal of something.
The one woman in the department. Yeah.
And it's just I mean but that is also
the fuel of innovation that jealousy
that tension that's well you know the
expression I'm sure um the battles are
so bitter in academia because the stakes
are so low. That's a beautiful way to
phrase it. But also like we shouldn't
forget I mean that I love seeing that
even in academia because it's humanity
the silliness it's there is a degree to
academia where the reason you're able to
think about some of these grand ideas is
because you still allow yourself to be
childlike. Oh yeah, there's a childlike
nature to be ask questions but children
can also be like children children. So
like you don't I think when um in in in
a corporate context and maybe the world
gets forces you to behave you're
supposed to be a certain kind of way
there's some aspects and it's a really
beautiful aspect to preserve and to
celebrate in academia is like you're
just allowed to be childlike in your
curiosity and your exploration you're
just exploring asking the biggest
questions the best scientists I know
often ask the simplest questions
questions. Um they're they're really um
first of all there's probably some
confidence there, but also they're never
going to lie to themselves that they
understand something that they don't
understand. So even this idea that
Newton didn't understand the apple
falling from the tree, he had he lived
another couple hundred of years, he
would have invented relativity because
he never would have lied to himself that
he understood it. he would have kept
asking this very simple question. Um,
and uh, I think that there is this
childlike beauty to that. Absolutely.
Yeah. Just some of the topics, I don't
know why I'm stuck to those two topics
of origin of life and consciousness, but
there's I'll talk about this. Some of
the most brilliant people I know are
stuck just like with Newton and
Einstein. They're stuck on that. This
doesn't make sense. I know a bunch of
brilliant biologists, physicists,
chemists, they're thinking about the
origin of life. They're like, "This
doesn't I know how evolution works. I
know how the biological systems work.
How genetic information propagates, but
like this this part, the singularity at
the beginning doesn't make sense. We
don't understand. We can't create in the
lab. They're bothered come every single
day. They're bothered by it. And that
being bothered by that tension, by that
gap in knowledge is uh yeah, that's the
catalyst. That's the fuel catalyst for
the discovery. But the discovery yeah
absolutely the discovery is going to
come because somebody couldn't sleep at
night and couldn't rest.
So in that way I think black holes are a
kind of portal into some of the biggest
mysteries of our universe. So it is a
it's a good terrain on which to explore
these ideas. So can can you speak about
some of the mysteries that the black
holes present us with? Yeah, I think
it's important to separate the idea that
there are these astrophysical states
that become black holes
um from being synonymous with black
holes because black holes are kind of
this this larger
um idea and uh they might have been made
primordally when the big bang happened
and they're there's something flawless
about black holes that makes them
fundamental.
um unlike anything else. So, uh they're
flawless in the sense that you can
completely understand a black hole by
looking at just its charge, electric
charge, its mass, and its spin. And
every black hole with that charge, mass,
and spin is identical to every other
black hole. You can't be like, "Oh, that
one's mine. I recognize it. It has this
little feature, and that's how I know
it's mine." They're featureless. They
you you try to put uh Mount Everest on a
black hole and it will shake it off in
these gravitational waves. It will
radiate away this imperfection until it
settles down to be a perfect black hole
again. So there's something about them
that is unlike and another reason why I
don't like to call them objects in a
traditional sense unlike anything else
in the universe that's
macroscopic. It's kind of a little bit
more like a fundamental particle. So, an
electron is described by a certain short
list of properties. Charge, mass, spin,
maybe some other quantum numbers. That's
what it means to be an electron. There's
no electron that's a little bit
different. You can't recognize your
electron. They're all identical in that
sense. Um, and and so in some very
abstract way, black holes share
something in common with microscopic
fundamental particles. And so what they
tell us about the fundamental laws of
physics um can be very
profound and it's
why even theoretical physicists,
mathematical physicists, not just
astronomers who use telescopes, they
rely on the black hole as a terrain to
perform their thought
experiments. And and it's because
there's something fundamental about
them. Yeah. General relativity means
quantum mechanics means singularity
and sadly heartbreakingly so it's out of
reach for experiment at this moment but
but within reach for theoretical it's in
reach for for thought experiments for
thought experiments which are quite
beautiful well on that topic I have to
ask you about the paradox the
information paradox of black holes what
is it so this is what catapulted
Hawkings fame
when he was a young researcher, he was
thinking about black holes and wanted to
just add a little smidge of quantum
mechanics, just a little smidge, you
know, wasn't going for full-blown
quantum gravity, but kind of just
asking, well, what if I allowed this
nothing, this vacuum, this empty space
around the event horizon, the star is
gone, there's nothing there. What if I
allowed it to possess sort of ordinary
quantum properties just a little tiny
bit you know nothing
dramatic don't go crazy you know and one
of the properties of the vacuum that um
is intriguing is this idea that you can
never say the vacuum is actually
completely empty we talked about
Heisenberg but you know the Heisenberg
uncertainty principle really kicked off
a lot of quantum mechanical thinking it
says that you can never exactly know a
particle's position simultaneously ly
with its motion, with its momentum. You
can know one or the other pretty
precisely, but not both precisely. And
the uncertainty isn't a lack of ability
that will technologically overcome. It's
foundational. So that there's in some
sense when it's in a precise location,
it is fundamentally no longer in a
precise motion. And that uncertainty
principle means I can't precisely say a
particle is exactly here, but it also
means I can't say it's not. Okay? And so
it led to this idea that what do I mean
by a vacuum? Because I can't 100%
precisely know. In fact, there's not
really meaningful to say that there's
zero particles here. And so what you can
say, however, is you can say, well,
maybe particles kind of froth around in
this seething quantum sea of the vacuum.
Maybe two particles come into existence
and they're entangled in such a way that
they cancel out each other's properties.
So they they have the properties of the
vacuum, you know, they don't they don't
destroy the kind of properties of the
vacuum because they cancel out each
other's spin, maybe each other's charge,
maybe things like that, but they kind of
froth around. They come, they go, they
come, they go and that's what we really
think is the best that empty space can
do in a quantum mechanical universe.
Now, if you add an event horizon, which
as we said is really fundamentally what
a black hole is, that's the most
important feature of a black hole. The
event horizon, if the particles are
created slightly on either side of that
event horizon, now you have a real
problem. Okay? Now, the pair has been
separated by this event horizon. Now,
they can both fall in. That's okay. But
if one falls in and the other doesn't,
it's stuck. It can't go back into the
vacuum because now it has a charge or it
has a spin or it has something. It's no
longer the property of that vacuum it
came from. It needs its pair to
disappear. Now it's stuck. It exists.
It's like you've made it real. So in a
sense, the black hole steals one of
these virtual particles and forces the
other to live.
And if it is, it'll escape radiate out
to infinity and look like to an observer
far away that the black hole is actually
radiated a particle. Now the particle
did not emanate from inside. It came
from the vacuum. It stole it from empty
space from the nothingness that is the
black hole. Now the reason why this is
very tricky is because in the process
because of this separation on either
side of the event horizon. The particle
it absorbs it has to do with the
switching of space and time that we
talked about. But the particle it
absorbs well from the outside you might
say oh it had negative momentum. It was
falling in from the inside you say well
this is actually motion and time. This
is energy. It has negative energy and it
is absorbs negative energy. Its mass
goes down. the black hole gets a little
lighter and as it continues to do this
the black hole really begins to
evaporate. It does more than just
radiate. It evaporates
away. And um it's intriguing because
Hawking said, "Look, this is going to
look thermal, meaning featureless. It's
going to have
no information in it. It's going to be
the most informationless possibility you
could possibly come up with when you're
radiating particles. It's just going to
look like a thermal distribution of
particles, like a hot body. And the
temperature is going to only tell you
about the mass, which you could tell
from outside the black hole anyway. You
know the mass of the black hole from the
outside. So, it's not telling you
anything about the black hole. It's got
no information about the black hole.
Now, you have a real problem. And when
he first said it, a lot of people
describe that not everyone understood
how really naughty he was
being. He did. Um, but some people who
love quantum mechanics were really
annoyed. Okay, people like Lenny Suskin,
Jerard, Nobel Prize winner, they were
mad because it suggested something was
fundamentally wrong with quantum
mechanics if it was right. Um, and the
reason why it says there's something
fundamentally wrong with quantum
mechanics is because quantum mechanics
does not allow this. It does not allow
quantum information to simply evaporate
away and poof out of the universe and
cease to exist. It's a violation of
something called unitarity. But really
the idea is it's the loss of quantum
information that's intolerable. Quantum
mechanics was built to preserve
information. It's one of the sacred
principles as sacred as conservation of
energy. In this example, more sacred
because you can violate conservation of
energy with Heisenberg's uncertainty
principle a little tiny bit.
um but so sacred that it created what
became um coined as the black hole wars
where people were saying
look general relativity is wrong
something's wrong with our thinking
about the event horizon or quantum
mechanics isn't what we think it is but
the two are not getting along anymore
and just to tell you how dramatic it is
so the temperature goes down with the
mass of the black hole heavier a black
hole the cooler it is so we don't see
Black holes evaporate, they're way too
big. But as they get smaller and
smaller, they get hotter and hotter. So
as the black hole nears the end of this
cycle of evaporating away, it takes a
very long time, much longer than the age
of the universe. Um it will be as though
the curtain, the event horizon's yanked
up, like it'll literally explode away.
Just boom. And the event horizon in
principle would be yanked up.
Everything's gone. all that information
that went into the black hole, all that
sacred quantum stuff gone. Poof. Okay?
Because it's not in the radiation
because the radiation has no
information. And um and
so it was an incredibly productive
debate because in it are the signs of
what will make gravity and quantum
mechanics play nice together. You know,
some quantum theory of gravity. Um,
whatever these clues are, and they're
hard to assemble. Uh, if you want a
quantum gravity theory, it has to
correctly predict the temperature of a
black hole, the entropy of a black hole.
It has to have all of these correct
features. The black hole is the place on
which we can test quantum gravity, but
it still has not been resolved. It has
not been fully resolved. I looked up all
the different ideas for the resolution.
So, there's the information loss, which
is what you referred to. It's perhaps
the simplest yet most radical resolution
is that information is truly lost. This
would mean quantum mechanics as we
currently understand it specifically
unitarity is incomplete or incorrect
under these extreme gravitational
conditions. I'm unhappy with that. I'm I
would not be happy with information
loss. I love that it's telling us that
there's this crisis cuz I do think it's
giving us the clues and we have to take
them seriously. For you the the gut is
like unitarity is going to be preserved
preserved. So quantum mechanics is we
have to come to the rescue as Lenny
Suskin in his book black hole war says
uh his subtitle is um my battle with
Stephen Hawking to make the world safe
for quantum mechanics. Quantum mechanics
I love something to that effect. So then
from string theory one of the
resolutions is called fuzzballs. I love
physicists so much. Originating from
string the theory this proposal suggests
that black holes aren't singularity
surrounded by empty space and an event
horizon. Instead, they are horizonless,
complex, tangled objects, aka fuzzballs,
made of strings and brains roughly the
size of the wouldbe event horizon.
There's no single point of infinite
density and no true horizon to cross. In
some sense, it says there's no interior
to the black hole. Nothing ever crosses.
So, I gave you this very nice story that
there's no drama. Sometimes that's how
it's described at the event horizon and
you fall through and there's nothing
there. This other idea says, well, hold
on a second. If it's really strings, as
I get close to this magnifying quality
and the slowing time down near the event
horizon, it is as though I put a
magnifying glass on things and now the
strings aren't so microscopic. They kind
of shmear around and then they get
caught like a tangle around the event
horizon and they just actually never
fall through. Um, I don't think that
either, but it was interesting. So, it's
just adding a very large number of extra
complex degrees of freedom. Yeah, there
are no teeny tiny marbles to fall
through, but it's similar to what we
already have with quantum mechanics.
It's just giving a
really saying the interior is just not
there ever. Nothing falls in. So, the
information gets out cuz it never went
in in the first place. Oh, interesting.
So, there is a strong statement there. A
strong statement there. Yeah. Okay. Soft
hair challenges the classical no hair
theorem by suggesting that black holes
do possess subtle quantum quote hair.
This isn't classical hairike charge, but
very low energy quantum
excitations, soft gravitons or photons
at the event horizon that can store
information about what fell in. Worth
trying, but I also don't think that
that's the case. So the no hair theorems
are um
formal proofs that the black hole is
this featureless perfect fundamental
particle that we talked about that all
you can ever tell about the black hole
is its electrical charge, its mass and
its spin and that it cannot possess
other features. It has no hair is one
way of describing it and that those are
proven mathematical proofs in the
context of general relativity. So the
idea is well therefore I can know
nothing about what goes into the black
hole. So the information is lost. But if
they could have hair I could say that's
my black hole because it have features
that I could distinguish and it could
encode the information that went in in
this way. And and the event horizon
isn't so serious. There isn't such a
stark demarcation between events inside
and outside and where I can't know what
happened inside or outside. And um I
don't think that's the resolution either
but it was worth a try. Okay. The pros
and cons of that one. The pros, it works
within the framework of quantum field
theory in curved spaceime potentially
requiring less radical modifications
than fuzballs or information loss.
Recent work by Hawking Perry Strongly
revitalized this idea. The cons is that
the precise mechanism by which
information is encoded and transferred
to the radiation is still debated and
technically challenging to work out
fully and indeed it needs to store a
vast amount of information. Okay,
another one. This is a weird one. boy is
uh ER equals EPR. This is probably it
though. Oh boy. So ER equals EPR is
Einstein Rosen Bridge equals Einstein
Podski Rosen Bridge posits a deep
connection between quantum entanglement
and space-time geometry. Uh specifically
Einstein Rosen bridge commonly known as
wormholes. It suggests that entangled
particles are connected by a
non-traversible wormhole. are tiny
wormholes connecting. Okay, I I can say
that this is not
uh a situation we can follow the chalk.
We can't start at the beginning and
calculate to the end. So, it's um it's
still a conjecture. I think it's very
profound though. Um I kind of imagine
Juan Maldsina who's part of this with
Lenny Suskin, they were kind of like h
it's like er equals EPR. They couldn't
even formulate it properly. It was like
an intuition that they had kind of
landed on and now are trying to
formalize. But to take a step back, one
way of thinking about ER equals EPR, you
have to talk about holography first. And
holography both Juan Maldina really
formalized it, Lenny Suskin suggested
it. The idea of a black hole hologram is
that all of the information in the black
hole whatever it is whatever you know
entropy as a measure of information uh
whatever the entropy of the black hole
is which is telling you how much
information is hidden in there how much
information you don't have direct access
to in some sense um is completely
encoded in the area of the black hole
meaning as the area grows the entropy
grows it does not grow as the volume
this actually turns out to be really
really important
If I tried to pack a lot of information
into a volume, more information than I
could pack, let's say, on the surface of
a black hole, I would simply make a
black hole and I would find out, oh, I
can't have more information than I can
fit on the surface. So, Lenny coined
this a hologram. People who take it very
seriously say, well, again, maybe the
interior of the black hole just doesn't
exist. It's a holographic projection of
this two-dimensional surface. In fact,
maybe I should take it all the way and
say, so are we. Mhm. The whole universe
is a holographic projection of a lower
dimensional surface, right? And so
people have struggled, nobody's really
landed it to find a universe version of
it. Oh, maybe there's a boundary to the
universe where all the information is
encoded and this entire
three-dimensional reality that's so
compelling and so convincing is actually
just a holographic projection. Juan
Maldesina did something absolutely
brilliant. It's the most highly cited
paper in the history of physics. It was
published in the late '9s. Uh it has a
very opaque title that would not lead
you to believe it's as revelatory as it
is. But he was able to show that a
universe like in a box with gravity in
it. It's not the same universe we
observe. Doesn't matter. It's just a
hypothetical called an anti-itter space.
It's a universe in a box. It has
gravity. It has black holes. It has
everything gravity can do in it. on its
boundary is a a theory with no gravity,
a universe that can be described with no
gravity at all. So, no black holes and
no information loss
problem. And they're
equivalent. That the interior universe
in a box is a holographic
projection of this quantum mechanics on
the boundary. pure quantum mechanics,
purely unitary, no loss of information.
None of this stuff could possibly be
true. There can't be loss of information
if this dictionary really works. If the
interior is a hologram, a projection of
the boundary. I know that's a lot. Yeah.
So, there's a there's some mathematics
there. There's physics and then there's
trying to conceal what that actually
means practically for for us. Mhm. Well,
what it would mean for us is that
information can't be lost even if we
don't know how to show it in the
description in which there are black
holes. It means it can't possibly be
lost because it's
equivalent to this description with no
gravity in it at all. No event horizons,
no black holes, just quantum mechanics.
So it really strongly suggested that
that quantum mechanics was going to win
in this battle, but it didn't show
exactly how it was going to win. So then
comes ER equals EPR. A visual way to
imagine what this means. So ER has to do
with little
wormholes. EPR Einstein Podski Rosen has
to do with quantum entanglement. The
idea was, well, maybe the stuff that's
interior to the black hole is quantum
entangled, like EPR, quantum entangled
with the Hawking radiation outside the
black hole that's escaping. And that
quantum entanglement is what allows you
to extract the information because it's
not actually physically moving from the
interior to the exterior. It's it's just
subtle quantum entanglement. And in
fact, I can kind of think of the entire
black hole. If I look at it, it looks
like a solid shadow cast on the sky,
some region of spaceime. If I look at it
very closely, I will see, oh no, it's
actually sewn from these quantum
wormholes, like embroidered. And so when
I get up close, it's almost as though
the event horizon isn't the fundamental
uh feature on the spacetime. The
fundamental feature is the quantum
entanglement embroidering the event
horizon. The embroidering is is just
tiny wormholes. So the quantum
entanglement is when two particles are
connected at arbitrary distances and
they're connected by a wormhole. And in
this case they would be connected by a
wormhole. Mhm. So the reason why that's
helpful, it helps you connect the
interior to the exterior without trying
to pass through the horizon. The cons of
this theory is highly conceptual and
abstract. The exact mechanism for
information retrieval via these
non-traversible war polls is not fully
understood. Primarily explored in
theoretical toy models. Whoa, Gemini
going hard. Uh theoretical toy models
like the anti-deitter spaceime rather
than realistic black holes. True. We do
what we can do.
in baby steps. So the uh another idea to
resolve the information paradox is
firewalls
proposed by Mary Marov Pchinski and
Sully amps. This is a more drastic
scenario arising from analyzing the
entanglement requirements of Hawking
radiation to preserve unitarity and
avoid information loss. They argued that
the entanglement structure requires the
event horizon not to be smooth, not to
be the smooth unremarkable place
predicted by general relativity, the
equivalence principle. Instead, it must
be a highly energetic region, a quote
firewall that incinerates anything
attempting to cross it. Okay. So, yeah,
that's a nice solution. Just destroy
everything that crosses them. Um, do you
find this at all a convincing resolution
to the information? would say the
firewall papers were fascinating and
were very provocative and very important
in making progress. I don't even think
the authors of those papers thought
firewalls were real. I think they were
saying, "Look, we've been brushing too
much under the rug." And if you look at
the evaporation process, it's even worse
than what you thought previously. It's
so bad that I can't get away with some
of these prior solutions that I thought
I could get away with. Um there was a
kind of duality idea or a
complimentarity idea that oh well maybe
one person thinks they fell in one
person thinks they never fell in and
that's okay you know no big deal. They
sort of exposed flaws in these kind of
approaches and it actually reinvigorated
the campaign to find a solution. Um so
it stopped it from stalling. I don't
think anyone really believes that the
event horizon, at the event horizon,
you'll find a firewall. But it did lead
to things like the entangled wormholes
embroidering a black hole, which is um
was born out of an attempt to um address
the concerns that amps raised. So it did
lead to progress. So for you, the
resolution would uh I'm going back to
the vacuum. You're going back, the empty
space, the beautiful event horizon. Y
I'll give up um I'll give up locality
meaning that I will allow things to be
connected
non-locally by a wormhole. So that is
the weirdest thing you're willing to
allow for which is arbitrary distance
connection of particles through a
wormhole. But quantum mechanics must be
preserved. I'll entertain pretty weird
things but I think that's the one that
sounds promising. The implications are
so dramatic because this is why you
start to hear things like, "Wait a
minute. If the event horizon only exists
when it's sewn out of these quantum
threads, does that mean that gravity is
fundamentally quantum mechanics?" Not
that gravity and quantum mechanics get
along and I have a quantum gravity
theory and I now know how to quantize
gravity. Actually, something much more
dramatic. Gravity is just kind of
emerging from this quantum description
that gravity isn't fundamental.
And what is the only thing that we have
when we go rock bottom, when we go
deeper and deeper, smaller and smaller
is quantum mechanics. So all of this
like spacetime looks nice and smooth and
continuous. But if I look at the quantum
realm, I'll see everything sewn together
out of quantum threads and that
spacetime is not a smooth continuum all
the way down. Now people already thought
that, but they thought it kind of came
in chunks of spaceime. instead. Maybe
it's just quantum mechanics all the way
down. Quantum threads. So these
entangled particles connected by
wormholes.
So that's what that's how you would how
would you even visualize a black hole in
that way. So it's all
um I mean it's all sort of from our
perspective in terms of detecting things
the light goes going in it's all still
the same. But when you zoom in a lot,
when you zoom in a lot to the quantum
mechanical scale at which you're seeing
the Hawking radiation, you would be
noticing that there's there's some
entanglement between the radiation that
I could not explain before and the
interior of the black hole. So, it's now
no longer a
perfectly thermal spectrum with no
features that only depends on the mass.
it actually has a way to have an imprint
of the information interior to the black
hole in the particles that um escape.
And so now in principle I could sit
there for a very long time. It might
take longer than the age of the universe
and collect all the Hawking radiation
and see that it actually had details in
it that are going to explain to me what
was interior to the black hole. So the
information is no longer lost. So yeah,
so information is not being destroyed.
So in theory, you should be able to get
information. Now I can't do that anymore
than I can recover the words on that
piece of paper once it's been burnt. But
that's a practical limitation, not a
fundamental one. It's just too hard. But
when I burn a piece of paper,
technically the information is all there
somewhere. It's in the smoke. It's in
the currents. It's in the molecules.
It's in the ink molecules. But in
principle, if I had took the age of the
universe, I could probably reconstru I
should be able to in principle
reconstruct the piece of paper and all
the words on it.
Do you think a theory of everything that
unifies general relativity, quantum
mechanics is possible? So, we're like uh
skirting around it. Yeah, we're skirting
around it. I think that this is the way
to find that out. It's going to be on
the train of black holes that we figure
out if that's possible.
Um I think that this is suggesting that
there might not be a theory of quantum
gravity that gravity will emerge at a
macroscopic level out of quantum
phenomena. Now we don't know how to do
that yet but these are all hints emerge.
So a lot of the mathematics of anything
that emerges from complex system is very
difficult to the transition is very
difficult right so if that's the case
there might not be a simple clean
equation that that connects everything
there are examples of emerging phenomena
which are very simple and clean like I
can just take electromagnetic scattering
just um law of physics where particles
scatter just by electromagnetically and
I have a lot of them and I have a lot of
them in this room and they come to some
average well I call that temperature,
right? And that one number, the fact
that there's one number describing all
of these gazillions of particles is an
emergent quantity. It's there's no
particle that carries around this
fundamental property called temperature,
right? Um it emerges from the collective
behavior of tons and tons of particles.
In some sense, temperature is not a
fundamental quantity. It's not a
fundamental law of nature, right? It's
just what
happens from the collective behavior.
And that's what we'd be saying. We'd be
saying,
"Oh, this this emerges from the
collective behavior of lots and lots and
lots of um quantum interactions." So
when do you think we would have some
breakthroughs on
uh the path towards theory of everything
showing that it's possible or impossible
all that kind of stuff? If you look at
the 21st century, say you're move 100
years into the future and looking back,
when do you think the breakthroughs will
come? So I'll give you some hard
problems. I guess my question is how
hard is this problem? Your like what
does your gut say? Because you know
finding the origin of life, figuring out
consciousness, solving some of the major
diseases. Then there's the theory of
everything, understanding this,
resolving the information paradox.
So these puzzles that are before us as a
human civilization,
physics, this feels like really one of
the big ones. Of course, there could be
other breakthroughs in
physics that don't solve this. Yeah, we
could discover dark matter, dark energy.
We could discover extra spatial
dimensions. We could discover that those
three things are linked, that there's
like a dark sector to the universe
that's hiding in these extra dimensions.
And that's something that I love to work
on. I think is really
fascinating. All of those would also be
clues about this question, but they
wouldn't solve this problem.
Um I think there I think it's impossible
to predict. There has been real progress
and the progress as we've said comes
from the childlike curiosity of saying,
"Well, I don't actually understand this.
I'm going to keep leaning on it because
I don't understand it." And then
suddenly you realize nobody really
understood it. Um so I don't I don't
know. Do I think it's a harder problem
than the problem of the origin of life?
I think it's technically a harder
problem. Um, but I don't know. Maybe
maybe the breakthrough will come. So,
when you mentioned discovering extra
dimensions, what do you mean? What could
that possibly mean?
Well, we we know that there are three
spatial dimensions. We like to talk
about time as a dimension. We can argue
about whether that's the right thing to
do, but we don't know why there are only
three. It very well could be that there
are extra spatial dimensions that
there's like a little origami of these
tightly rolled up dimensions. Um, not
all of them, not all the models require
that they're small, but most do. String
theory requires extra dimensions to make
sense. But even if you uh feel very um
hostile towards string theory, there are
there are lots of reasons to consider
the viability of extra
dimensions. And we think that they can
trap little quantum energies in such a
way that might align with the dark
energy. And the numerology is not
perfect. It's a little bit subtle. it's
hard to stabilize them. Um, it's
possible that there are these kind of
quantum exitations that look a lot like
dark matter. It's kind of an interesting
idea that in the Big Bang, the universe
was born with lots of these dimensions.
They were all kind of wrapped up in the
early universe. And what we're really
trying to understand is why did three
get so
big and and why did the others stay so
small? Is it possible to have some kind
of natural selection of dimensions kind
of situation? There is actually and
people have worked on that. Is there a
reason why it's uh easier to unravel
three? Some people think about strings
and brains wrapping up in the extra
dimensions causing a kind of
constriction but preferentially
loosening up in three. Um, sometimes we
look at exactly models like that which
have to do with the origami uh being
resistant to change in a certain way
that only allows three to unravel and
keeps the others really taught. But then
there are other ideas that we're
actually living on a three-dimensional
membrane that moves through these higher
dimensions. And so the reason we don't
notice them isn't because they're small.
Maybe they're not small at all. But it's
because we're stuck to this membrane.
So, we're unaware of these extra
directions. Is it possible that there's
other intelligent alien civilizations
out there that are
operating on a different
membrane? Is is this a bit of an out
there question? But I I ask it more kind
of seriously like is it possible do you
think from a physics perspective to
exist on a
slice of uh what the universe is capable
of? I think it is
certainly mathematically possible on
paper to imagine a higher dimensional
universe with more than one
membrane.
And if things are mathematically
possible, I often wonder if nature will
try it out. Yeah. Um, which is how
people get into the the strange
territory of talking about a multiverse.
Because if you start to say one of the
aspirations was in the same way that we
identified the law of electroeak theory
of matter that it was a single
description and exactly um landed on the
description that matched observations.
People were hoping the same thing would
happen for a kind of theory that also
incorporated gravity. there would be
this one beautiful law, but instead they
got a proliferation, all of which did
okay or did equally badly. Um, they
suddenly had trouble finding not only
finding a single one, but sort of that
would just beg a new question, which is,
well, why that one? And if if nature can
do something, won't she do anything she
can try? And so maybe we really are just
one example in an infinite sea of
possible universes with slightly
different laws of physics. So if I can
do some of these things on paper, like
imagine a higher dimensional space in
which I'm confined to a brain and
there's another brain or maybe a whole
array of them. Maybe nature's tried that
out somewhere. Maybe that's been tried
out here. Um, and then yes, is it
possible that there's life and
civilizations on those other brains?
Yeah, but we can't communicate with
them. They'd be like in a shadow space.
Can you seriously say we can't
communicate with them? No, that's fair.
I there I'm limited in my communication
cuz I'm glued to the brain. But some
things can move. We call the bulk
through the bulk. Gravity, for instance,
a gravitational wave. So I could design
a gravitational
communicator communication system and I
could send gravitational waves through
the bulk and how SETI is doing with
light into space. I could um send
signals into the bulk. Nice. Telling
them where we are and what we do and of
course singing songs. Sending
gravitational waves is very expensive.
We don't know how to very expensive very
hard to localize. They tend to be long
wavelength and very hard to do. lot of
energy moving around. A lot of energy.
Uh, so is it possible that the membranes
are quote unquote hairy in other ways,
like some kind of weird? It is possible
that there's other things that live in
the bulk. I mean, last night I was
calculating away looking at something
that lives in the bulk. Okay, this is
fascinating. So, I mean, okay, can we
take a little bit more seriously about
the the whole when I look out there
at the stars? Mhm. I from a basic
intuition cannot possibly imagine
there's not just alien civilizations
everywhere. Yeah. Life is so damn good.
Like you said, nature tries stuff out.
Yeah. Nature's an experimentter. And I
just can't just basic sort of uh
observation life uh you said somewhere
that you like extreop files life just
figures out it just finds a way to
survive. Now there could be something
magical about the origin of life the
first spark but like I can't even see
that it's over and over and over. I bet
actually once once the story is fully
told and figured out, life originated on
Earth almost right away and did that. So
like billions of
times uh in multiple places just over
and over and over and over. Uh that
seems to be the thing that just whatever
is the life force behind this whole
thing seems to uh seems to create life
seems to be a creator of different
sorts. Yeah. the the the very from the
very original primordial soup of things.
It just creates stuff. So, I just can't
imagine, but we don't see the aliens.
So, right. Yeah. We don't even have to
go to something as crazy as extra
dimensions and brain worlds and all of
that. What's happening right now in the
past 30 years in astronomy looking at
real objects is that the number of
planets, exoplanets outside our solar
system has absolutely proliferated.
There are probably more planets in the
Milky Way galaxy than there are stars.
And now we have a real quandry. Not I
don't think it's quandry. I think it's
really exciting. It becomes impossible.
What you just said, I totally agree
with. It becomes impossible to imagine
that life was not sparked somewhere else
in our Milky Way galaxy and maybe even
in our local neighborhood of the Milky
Way galaxy, maybe within a few hundred
lighty years of the Milky of of of our
solar system. So my my my gut says like
some crazy amount of uh solar systems
have life bacterial life somewhere at
some point in their history had some
bacterial type of life something like
bacterial maybe it's totally different
kinds of life so then I'm just facing
with a question it's like why have we
not clearly seen alien civilizations and
there the answer I I just I I don't find
any great filter answer convincing.
There's just no way I can imagine an
advanced alien civilization not avoiding
its own destruction. I can see a lot of
them getting into trouble. I could see
how we humans are really like 50/50
here. Well, isn't that kind of
appalling? I mean, just take that
statement. We've only been around for
like I mean couple hundred thousand
years tops, you know? Um, that is not
very long and we're at a 50/50. I mean,
that's unbelievable. I mean, it's
indisputable that we have created the
means at least potentially for our own
destruction. Will we learn from our
mistakes? Will we avert course and save
ourselves? One hopes so, right? But but
even the concept that it's conceivable
whales have not invented a way to kill
themselves to wipe out all whales and
earth and life on earth. That's one way
to see it. But I I actually see it as a
feature not a bug when you look at the
entirety of the universe because uh it
does seem that the mechanism of
evolution constantly
creates you want to operate on the verge
of destruction. It seems like I mean the
predator and prey dynamic is really
effective at
creating a at accelerating evolution and
development. It seems like us being able
to destroy ourselves is a really
powerful way to give us a chance to
really get our together and to
flourish to develop to innovate to to uh
go out amongst the stars or 50/50
destroy ourselves. But like, which I
think me as a human is a horrible thing.
But if there's a lot of other alien
civilizations, that's a pretty cool
thing. You want to give everybody
nuclear weapons,
half of them will figure it out, half of
them won't. And the ones that give
everyone all these civilizations, all
these civilizations, and then the ones
that figure it out will figure out some
incredible technologies about how to
expand, how to develop, and all that
kind of stuff, right? You could use a
kind of evolutionary Darwinian natural
selection on that where in survival
isn't just in a harsh naturally induced
climate change but is because of a
nuclear holocaust and so but and then
and then something will will be created
that is now impervious to that that now
knows how to survive. Yep. Exactly. So
why haven't we seen them? Right. Well
because that's a pretty big bar. So if
you look at the just to say for a
comparison dinosaurs you know 250
million
years I mean maybe not very bright
um didn't invent but fire didn't write
sonnets they didn't contemplate the
origin of the universe but they they
lived
and um in a benign situation without
confronting their own demise at their
own hands pause
um so It's just a sheer numbers game.
That's a long time, 250 million years. I
do think though that life can flourish
without wanting to manipulate its
environment. And that we do see many
examples of species on Earth that are
very longived, very very longived. Um,
and have very different states of
consciousness. They have the jellyfish
does not even have a localized brain.
Um, I don't think they have a heart or
blood. I mean, they're really different
from us. Okay? And that's what I think
we have to start thinking about when we
think about aliens. Those, uh, species
have lived for a very, very long time.
They even show some evidence of
immortality. You can wound one badly,
and there are certain jellyfish that
will go back into a kind of pre-state
and start over. So, I think we're very
attached to imagining creatures like us
that manipulate technology. Um, and um,
and I think we have to be way more
imaginative
uh, if we're going to really take
seriously life in the universe. Yeah.
They might not prioritize conquest and
expansion. Mhm. They might not be
violent. They might not be violent like
us humans. They might be solitary. They
might not be social. They might not move
in groups. They might not want to leave
records. Um, uh, they might again not
have a localized brain or have a
completely different kind of nervous
system. I think all we can say about
life is it has something to do with
moving electrons
around and um, like neurologically we
move electrons through our nervous
system. Our brain has electrical
configurations. We metabolize food and
that has to do with uh getting energy,
electrical energy in some sense out of
um what we're eating. You we organisms
on the earth that can eat rocks. It's
quite amazing. Minerals. I mean, talk
about extreophiles. They can metabolize
things that I would have thought uh were
impossible to metabolize. And so, again,
I think we we have to kind of open our
minds to how strange that could be
um and how different from us. And we are
the only example even here on earth that
that does manipulate its environment in
that extreme way. I mean can you think
of life as cuz you said
electrons is is there some degree of
information processing required? So like
it does something interesting in quotes
with information. I think there are
arguments like that. um how entropy is
changing from the beginning of the
universe to today. How life uh lowers
entropy by organizing things but it
costs more as a whole system. So the
whole entropy of the whole system goes
up. But um but of course I I organized
things today and reduced the entropy of
certain things in order to get up and
get here. um and even having this
conversation organizing thoughts um out
of the cloud of information but it comes
at the cost of the entire system
increasing um entropy so I do think
there's probably a very interesting way
to talk about life in this way I'm sure
somebody has yeah yeah it creates local
pockets of low entropy and then the kind
of mechanism the kind of object the kind
of life form that could do that probably
can take arbitrary forms and you could
think now if you you reduce it all to
information. Now you can start to think
about physics and in the realm of
physics with with the multiverse and all
this kind of
stuff. You could start to think about
okay how do I detect those pockets of
low entropy? Mhm. Yeah. I mean people
have tried to make arguments like that
like can I look for entropic arguments
that might suggest we've done this
before? the big bang has happened
before. So, is it possible that there's
some kind of physics explanation why we
haven't seen the aliens? Like we said,
membranes, I don't think membranes is
going to explain why we don't see them
in the Milky Way. I think that is just a
problem we're stuck with. whether or not
there are extra dimensions or whether or
not there's life in another membrane. Um
I think we know that even just in our
galaxy which is a very small part of the
universe um 300 billion stars something
like that a whole kind of variety of
possibilities to be explored by nature
in the same way that we're describing.
And I think you're absolutely right when
when life was kicked off first sparked
here on Earth it was voracious. Now, it
took a really long time though to get to
multisellularity. I think that's
interesting. That's weird. It's weird.
It took a really really long time to
become
multisellular. But it it did not take
long just to start. Yeah. What do you
think is the hardest thing on the chain
of leaps that got to humans? I would say
multisellularity, which is strictly an
energy problem. I I think again it's
just like can electrons flow the right
way? Uh and is it energetically
favorable for
multisellularity to exist? Because if
it's energetically expensive, it's not
going to succeed. And if it's
energetically favorable, it's going to
take off. It's really just and that's
why I also think that going from
inanimate
um to animate is probably gray. Like the
transition is gray. At what point we
call something fully alive? Famously,
it's hard to make a nice list of bullet
points that need to be met in order to
declare something alive. Is a virus
alive? I mean, I don't know. Was a PON
alive? Those are they seem to do some
things, but they kind of rely on
stealing other DNA and replicating. And
I don't know. I guess they're not alive.
But I mean, the point is is that it
really at the end of the day, I really
think it's just, you asked if it's just
physics. I mean, I think it's just this
these rules of energetics. And the gray
area between the non-living and the
living is way simpler just on Earth. And
you said it's already complicated on
Earth, but it's probably even more
complicated elsewhere where the
chemistry could be anything. Carbon is
really cool and really useful because it
finds a lot. It's nice. It finds a lot
of ways to combine with other things.
And that's complexity. And complexity is
the kind of thing you need for life. You
can't have a very simple linear chain
and expect to get life. But I don't
know, maybe sulfur would do. Okay. Okay.
As we get progressively towards crazier
and crazier ideas. So, we talked about
these microscopic wormholes, which you
know, my mind is still blown away by
that. But if we talk about a little bit
more seriously about wormholes in
general, also called the Einstein rose
and bridges, to what degree do you think
they're actually possible as a thing to
study, creeping towards the
possibility, maybe centuries from now,
of engineering ways of using them, of
creating wormholes and using them for
transportation of humanlike organisms. I
think wormholes are a perfectly valid
construction to
consider. They're just they're just a
curve in spaceime.
Um the topologically, which has to do
with the connectedness of the space, is
a little tricky because we know that
Einstein's description is completely in
terms of local curves and distortions,
expansion, contraction. But it doesn't
say anything about the global
connectedness of the space because he
knew that it could be globally connected
on the largest scales. This kind of
origami that we're talking about that
you could travel in a straight line
through the universe, leave our galaxy
behind, watch the Virgo cluster drift
behind us and travel in a straight line
as possible and find ourselves coming
back again to the Virgo cluster and
eventually the Milky Way and eventually
the Earth that we could find ourselves
on a connected compact spaceime. And so
topologically
um there's something we know for sure
something beyond Einstein's theory that
has to explain that to us. Now wormholes
are a little funky because they're
topological. You know they create these
handles and holes in these sneaky by
topological I mean these connected
spaces and yes it's like Swiss cheese or
something. like Swiss cheese and they
right and they so I could have you know
I I could have two like flat sheets that
are connected by a wormhole but then
wrap around on the largest scale you
know all this cool stuff um there's
nothing wrong with it as far as I can
see there's nothing abusive towards the
laws about a wormhole but we can reverse
engineer you we were saying oh look if I
know how matter and energy are
distributed I can predict how spaceime
is curved I can reverse engineer I can
say I want to build a curved spaceime
like a wormhole. What matter and energy
do I need to do that? It's a simple
process and it's kind of thing Hip
Thorne uh worked on very imaginative
creative person. Um and the problem was
that he said, "Oh, you know, here's the
bummer. The matter and energy you need
doesn't seem to be like anything we've
ever seen before. It has to have like
negative energy." And that's that's not
great. Um there are some conjectures
that we shouldn't allow things that have
that kind of a property that have
negative energies. U only things that
have positive energies are going to be
stable and longived. But we actually
know of quantum examples of negative
energy. So it's not that crazy. There's
something called the Casmir effect. You
have two metal plates and put them
really close together. You can see this
kind of quantum fluctuation between the
plates. It's called a kasmir energy. And
that can have a negative energy can
actually um cause the place to attract
or repel depending on how they're
configured. And and so you could kind of
imagine doing something like that, like
having wormholes propped up by these
kinds of quantum energies. And people
have thought of imaginative
configurations to try to keep them
propped up. Is it are we at the point of
me saying, "Oh, this is an engineering
problem." I'm not saying that quite yet,
but it's certainly plausible.
Yeah. So, you have to get a lot of this
kind of weird matter. You need a lot of
this weird matter to send a person
through, right? That's going to be
really telling. So, I'm not saying we're
it's simply an engineering problem, but
it's all within the realm of plausible
physics. I think I I think that's super
interesting. I think it's obviously
intricately deeply connected to black
holes. H is is it fair to think of
wormholes as just two black holes that
are connected somehow? Is that people
have looked at that? They tend to be
non-traversible wormholes. They're
they're not trying to prop them open. Um
but yeah, I mean some of this
er equals EPR, quantum entanglement,
they're trying to connect black holes.
Um you know, it's it's really cool. It's
not quite again it's not quite following
the chalk. And by that I mean we can't
exactly start at a concrete place
calculate all the way to the end yet. So
if I may read off some of the ideas that
kept throwing his head about how to
artificially construct wormholes. So the
first method involves quantum mechanics
and the concept of quantum foam. And
this is the thing we've been talking
about. Now to create a wormhole these
tiny wormholes would need to be enlarged
and stabilized to be useful for travel.
But the exact method of doing this
remains entirely theoretical. No
You think so? So this these tiny
wormholes that are basically um for the
quantum entanglement of the particles
somehow enlarged.
Man, playing with the topology of the
Swiss cheese would be so interesting.
Even to get a hint. Mhm. That would be
like top three if not one of maybe even
number one question for me to ask if I
got a a chance to ask an omnicient
being. omnicient being of like a
question that I can get answer to. Mhm.
Maybe with some visualization. Mhm. Like
the shape the topology of the universe.
Yeah. Like but like I need some details.
Unfortunately, I'll get an answer that I
can't possibly comprehend. Right. It's a
hyperbolic manifold that's identified
across Exactly.
You need to be able to ask a follow-up
question. Exactly. Yeah. That would be
so interesting. Anyway, um classical
quantum strategy. The second approach
combines classical physics with quantum
effects. This method would this method
would require an advanced civilization
to manipulate quantum gravity effects in
ways we don't yet understand. There's a
lot of in ways we don't understand.
Yeah, there's a lot of And then there's
exotic matter requirements. There's a
lot of But I can tell you I'm pretty
sure all of them have in common the
feature that they're saying here's what
I want my wormhole to look like first.
So it's like saying I want to build a
building first. So they ar they
construct there's an architecture of the
spaceime that they're after and then
they reverse the Einstein equations to
say what must matter and energy uh what
are the conditions that I impose on
matter and energy to build this
architecture which is unfortunately a
very early step of figuring out but it's
important because it's how they realized
oh wow they have to have these negative
energies they have to violate certain uh
energy conditions that we often assume
are true and then you either say, "Oh,
well then all bets are off they'll never
exist or you uh look a little harder and
you say, "Well, I can violate that
energy condition without it being that
big a deal." And um and again, quantum
mechanics often does violate those
energy conditions. So, do you think the
studying of black holes and some of the
topics we've been talking about will
allow us to travel faster than the speed
of light or travel close to the speed of
light or do some kind of really
innovative breakthroughs on the
propulsion technology we use for
traveling in space? Yeah. I mean,
sometimes I assign in an advanced
general relativity class the assignment
of inventing a warp drive and it's kind
of similar. So the idea is uh here's a
place you want to get to and can you
contract the spaceime between you with
some some kind of some something
antithetical to dark energy the opposite
and skip across and then push it back
out again. That's all can you can do
that in the context of general
relativity. Now I I can't find the
energy that has these properties but I
also can't find dark energy. So, so
we've already been confronted with
something that we look at the spaceime.
The spaceime is expanding ever faster.
We say, "What could possibly do that?"
We don't know what it is. But I can tell
you about its pressure. I can tell you
certain features about it. And I just
call it dark energy, but I actually have
no idea. It's just that name's just a
proxy for what this it should be called
invisible because it's not actually
dark. It's in this room. It's not hard
to see through. It's not dark. It's It's
literally invisible. Um, so maybe that
was a misnomer. But the point being, I
still don't fundamentally know what it
is. That's not so terrible. That's
that's the state of the world that we're
actually in. So maybe warp drive is just
kind of like a version of that. I I
don't know what form of matter can do
that yet, but at least I can identify
the features that are needed. So
figuring out what dark energy is might
land some clues. Yeah, it actually it
might. Um, it it is it is positive
energy. Um um and a negative pressure
which is kind of like a rubber band sort
of quality. We think of pressure as
pushing things outward and dark energy
has a very strange sort of quality that
as things move outward you feel more
energy as opposed to less energy. The
energy doesn't get lower, it gets more.
And um but it so it doesn't have the
right features for the wormhole. But
those are some pretty surprising
features. And we we again can conjecture
like oh hey you know the quantum energy
of the vacuum kind of behaves that way.
That would be a great resolution to the
dark energy problem. It's just the
energy of empty space and it's the
quantum energy of empty space. That's an
excellent answer. The problem is is by
all our methods and all the
understanding we have that energy is
either really really huge huge
um way bigger than what we see today or
it's like
zero. So that's a numbers problem. We
can't
naturally fine-tune the energy of empty
space to give us this really weird value
so that we just happen to be seeing it
today. But again we can think of a kind
of dark energy that exists. Um so the
question is just why is it it becomes
why is it such such a weird value. Um
not how is this conceivable because we
can't conceive of it. Yeah. But if it's
a weird value that means there is a
phenomena we don't understand. Yes.
There's absolutely a phenomenon.
Nobody's going to say they're happy with
that. We're all going to say there's
something we don't understand. which is
why we look to the extra dimensions
because then you can say, "Oh, maybe it
has to do with the size of the extra
dimensions or the way that they're
wrapped up or um and so maybe there it's
foisted on us because of the the
topology, the connectedness of the
higher dimensional space. These are all
things that we're exploring. Nobody's
landed one that's so compelling that uh
your friends like it as much as you do."
What what what do you think would lead
to the breakthroughs on dark matter and
dark energy? I think dark matter might
be
uh less peculiar
um than dark energy. My hope is that
they're tied together. That's that would
be very gratifying. These aren't just
separate problems coming from different
sectors, but that they're actually
connected. um that the reason the dark
matter is where it is in terms of how
much it's contributing to the universe
is is connected with why the dark energy
is showing up right now. I would love
that. That would be a solution like no
other, right? And and like I said, if it
revealed something about dark
dimensions, you know, that's that would
be a happy day. Correct me if I'm wrong.
Dark matter could be localized in space.
Yeah, dark matter is localized in space.
So, it clumps. I mean, it doesn't it
doesn't clump a lot, you know, but but I
mean, it's around the galaxy. It's in a
halo around the galaxy. So, people get
increasingly more confident that it
doesn't Oh, it's really compelling.
Yeah. I mean, you see um these images of
uh galaxies that clusters that that pass
through each other and you can see where
the light is, the luminous matter is
distributed. And then by looking at the
gravitational lensing which shows you
where the actual mass is distributed so
that light bends around the most massive
parts in a particular way. So you can
reconstruct where the mass is
gravitationally quite separate from
looking at the luminous matter which is
not dark and they are
separate because the stuff as they pass
through each other the interacting stuff
the luminous stuff collides and gets
stuck and you can see it colliding and
lighting up the dark stuff which by
definition it's dark because it doesn't
interact passes right through it's right
through each other right and this is I
mean it's so compelling And there's lots
of other um observations, but but that
one is just before you just look at it,
you can see that the mass is distributed
differently than the interacting
luminous matter. So, uh dark energy is
harder to get a hold of. Dark energy is
much harder to get a hold of. But, you
know, I mean, the Higs field could have
also explained dark energy. Yeah. Um, if
you've heard of the God particle, I
don't know if you know the originally
Leon Letterman co-authored a book and he
wanted to call it the goddamn particle
because I couldn't find it and his his
publisher convinced him to call it the
God particle. Uh, and he said he said
they managed to offend two groups, those
that believed in God and those that
didn't. That's a good line, too. Oh,
boy. He was very funny. He was very
witty. So, you know, Higs turned out to
be Higs great discovery. I mean,
unbelievable. Um, there it was. Build
this massive collider in CERN in
Switzerland and there it is.
Unbelievable. Kind of where you expect
it to be. Now, the reason I say it could
be dark energy is because the Higs
particle like a particle of light also
has a field like an electromagnetic
field. So light can have this field
that's distributed through all space,
electric magnetic field, and you shake
it around and it creates little
particles. So the Higs field is actually
more important than the Higs particle,
the complement to the Higs particle
because that's what you and I connect
with to get mass in our atoms. So the
idea is that our atoms are interacting
with this gooey field that's everywhere.
Mhm. And um and that's what's giving us
this experience of inertial mass, but we
don't actually inter there's not a lot
of quanta lying around. There's not a
lot of Higs particles lying around cuz
they decay. So it's the field that's
really important. And that field could
act like a dark energy. It's just
not in the right place, meaning it's not
at the right the energy's too high in to
explain this tiny tiny value today. And
again, we're back to this mismatch. It's
not that we can't conceive of forms of
dark energy, it's that we can't make one
where we where we're finding it. So, uh
I wonder if you can comment on something
that I've I've heard recently. There's
some people who say
uh people outside of physics say that,
you know, dark matter and dark energy is
just something physicists made up. Yeah.
to uh put a label on the fact that they
don't understand
a very large fraction of the universe
and how it operates. Is there some truth
to that? What's your response to that?
There's some truth to it, but but it's
really missing a huge point, which is
that if we did not understand the
universe as incredibly precisely as we
do, it's stunning that there's modern
precision cosmology. It's absolutely
incredible. uh when Kobe which is an
experiment that measured the light left
over from uh the big bang in the 80s
first revealed its observations I mean
there was applause you know people were
cheering right it was unbelievable we
had predicted and measured the light
left over from the big bang and because
of all the precision that's happened
since then that's how we're able to
confront that there's things that we
don't know and that's how we're able to
confront like, "Wow, this is really
everything everybody has ever seen and
ever will see as far as we understand
makes up less than 5% of what's out
there." Yeah. And and so I would say
yes, we're just giving proxy names to
things we don't understand. But to
dismiss that as some kind of oh, they
just don't know that it is actually
quite the opposite. It is a stunning
achievement to be able to stare that
down and to have that um so precise and
so compelling that we're able to to to
know that there's dark energy and dark
matter. I don't think those are disputed
anymore and they were up until, you
know, recently. They were still
disputed. I think we're still at such
early stages where we're not really even
at a good explanation. Right. You've
mentioned a few. Well, I can think of
examples of dark matter that exist that
we really know for sure are real
versions of dark matter, like nutrinos.
Right now, they're radiating through us.
That's very well confirmed. And they're
technically dark. They don't interact
with light and so we can't see them.
Right now, they're raining through us.
If we could see the dark matter in this
room and we absolutely know is coming
from the sun, it would be wild. Be a
rainstorm, you know, but they're just
invisible to us. Um, mostly they pass
through our bodies. Mostly they pass
through the earth. Occasionally they get
caught in some fancy detector experiment
that somebody built specifically to
catch solar. So dark matter is known to
exist. It's just again there's not
enough of it. It's not the right mass to
be the dark matter that makes up this
missing component. I wanted to say that
I was been recently fascinated by the
flat earth people because there's been a
split in the community. Mhm.
First of all, the community is
fascinating study of human psychology.
uh they did
um this experiment where I I forgot who
funded it, but they sent like physicists
and flatearthers Mhm. to Antarctica.
Really? And this split happened because
half of them got converted into round
earthers. Wow. Well, good for them. And
then but then the other half just went
that it was all a sigh out. Really?
That's fascinating. Did somebody film
that? That'd be a great documentary.
Yeah, it did. They did. I made a whole
thing. This was just at the end of last
year. There was a big I meaning cuz I I
I think that's such a clean study of
conspiracy theories because like there's
so many conspiracy theories have some
inkling of truth in them.
Like there's some elements about the way
governments operate or human psychology
that there's it's too messy. Flat Earth
to me is just clean. It's like spaghetti
monster or something like right. It's
just a cleanly wrong thing. So it's a
nice way to understand the psychology
how a large number of people can believe
a thing. Yeah. And why do they want to
believe a thing? What's very interesting
is um use trying to use rational
arguments. So I that makes it even more
confounding to me. I would understand
more somebody who just said, "Look, I
have faith and I believe these things
and it's not about reason and it's not
about logic and
okay. I mean, I don't relate to it, but
okay." Um, but to say I'm going to use
reason and
logic and to prove to you this
completely orthogonal conclusion that I
find really interesting. So, there's
some kind of romance. There's about
reason and logic. Yeah. But also there's
a questioning of institutions that's
really interesting and important to
understand. Well, I mean I
I actually
appreciate the
skeptics's stance. I don't scientists
also have to be skeptics. We have to be
childlike, naive, and somewhat in some
sense really open to anything, right?
Otherwise, you're not going to be a
flexible. You're not going to be at the
forefront. But but also to be skeptical.
Um, so I have respect for I guess I
that's exactly what I'm saying is more
confusing because to invoke skepticism
and then to want to use rational
argument. What is the other component
that's that's going into this because as
you said this is something that's easily
verified. I mean, we have people in
space. So, you have to believe a lot
more machinery
um that's a lot more difficult to
justify,
explain as a wild conspiracy. So,
there's something about the conspiracy
that stirs an emo a positive emotion. I
think one of the most incredible things
I have to talk to you about this, one of
the most incredible things that humans
have ever accomplished is LIGO. Hm.
We have to talk about gravitational
waves. And the the very fact that we're
able to detect gravitational waves from
the early
universe is effing wild. It's crazy.
Yeah. Can you explain what gravitational
waves are? And we should mention you
wrote a book about the humans about the
whole journey of detecting gravitational
waves and LIGO Black Hole Blues is the
book. But can you talk about
gravitational waves and how the hell
we're able to actually do it? Let's just
start with the idea of gravitational
waves. I have to move around a lot of
mass to make anything interesting
happening in gravity. I mean, if you
think about it, gravity is incredibly
weak. I mean, right now, the whole Earth
is pulling on me and I can still get out
of this chair and walk around. Like,
that's insane. The whole Earth, you
know, gravity's weak, right? Um, so to
get something going on in gravity, I
need like big objects and things like
black holes. So the idea is if black
holes curve space and time around them
in the way that we've been describing
things follow along the curves in space.
If the black holes move around, the
curves have to follow them, right? But
they can't travel faster than the speed
of light either. So what happens is as
black holes, let's say, move around,
maybe I've got two black holes in orbit
around each other. That can happen. It
takes a while. a wave is created in the
actual shape of space and that wave
follows the black holes as black holes
are undulating. Eventually, those two
black holes will merge and as we were
talking about, it doesn't take an
infinite time even though there's time
dilation because they're both so big.
They're really deforming spaceime a lot.
I don't have a little tiny marble
falling across an event horizon. I have
two event horizons. And in the
simulations, you can see it bobble and
they merge together and they make one
bigger black hole. And then it radiates
in the gravitational waves. It radiates
away all those imperfections and it
settles down to one quscent perfectly
silent black hole that's spinning.
Beautiful stuff. And it emits E= MC²
energy. So the mass of the final black
hole will be less than the sum of the
two starter black holes. And that energy
is radiated away in this ringing of
spaceime. It's really important to
emphasize that it's not light. None of
this has to do literally with light that
we can detect with normal things that
detect light. X-rays form of light.
Gamma rays are a form of light.
Infrared, optical, all this whole
electromagnetic spectrum. None of it is
emitted as light. It's completely dark.
It's only emitted in the rippling of the
shape of space. A lot of times it's
likened closer to sound. Technically,
we've kind of argued, I mean, I haven't
done an anatomical calculation, but if
you're near enough to two colliding
black holes, they actually ring spaceime
in the human auditory range. The
frequency is actually in the human
auditory range that the shape of space
could squeeze and stretch your eardrum
even in vacuum. And you could hear
literally hear these waves ringing.
[Music]
So the idea is that they're closer um to
something that you would want to map as
a sound than it's something as a
picture. Sorry. So what do you think it
would feel like to ride the
gravitational wave? So like to be to
exist to exist as you mentioned here
would literally bob around like your
orbit would change right if you were
orbiting these black holes two black
holes you'd be on a kind of complicated
orbit but your orbit would get tossed
about well how would the experience be
because you're inside spaceime yes I see
so the the the the black hole is
experienced within spacetime as a
squeezing and stretching. So you would
feel it as a sort of squeezing and
stretching and you would also find your
location change where your where you
would fall would be
redirected. Um so it's literally like a
squeezing and stretching. That's the way
to think about it. And and and it's very
detailed the sort of nature of this and
um but for many years people thought
well these gravitational waves kind of
have to exist for these intuitive
reasons I've described. spacetime's
curved. I move the curve. The wave has
to propagate um through that curved
spaceime. But people didn't know if they
really carried energy. The arguments
went on and back and forth and papers
written in decades, right? Um but I like
this sound an more than an analogy
because I I liken the black holes as
like mallets on the drum. The drum is
spacetime. Yeah. As they move, they bang
on the drum of spaceime and it rings.
Mhm. Remarkably, those gravitational
waves do things don't interfere with
them very much. So, they can travel for
two billion years, light years, you
know, in distance, two billion years in
time, and get to us kind of as they were
when they were emitted, quieter, more
diffuse, maybe they've stretched out a
little bit from the expansion of the
universe, but they're pretty preserved.
And so the idea of LIGO, this
instrument, is to build a gigantic
musical instrument. It's kind of like
building an electric guitar where the
electric guitar is recording the shape
of the string and it plays it back to
you through an amplifier. LIGO is trying
to record the shape of the ringing drum
and they literally listen to it in the
control room. just sort of hums and
wobbles and they're like trying to play
this recording drum back to you as
opposed to taking a snapshot. It's like
a in time. Yeah. But to construct this
guitar Yes. gigantic instrument has to
be very large and extremely precise.
It's unbelievable. I can't believe they
succeeded. I honestly I can't believe
they succeeded. It was so insane. It was
such a crazy thing to even attempt. It
took them 50 years. Really? It's people
who started in their 30s and 40s who
were in their 80s when when it
succeeded. I mean, imagine that
tenacity, the unbelievable commitment.
Um, but the sensitivity that we're
talking about is we have a this musical
instrument the s four kilometers
spanning four kilometers in a kind of
L-shape with these tunnels where there's
this the largest holes in the earth's
atmosphere because they pulled a vacuum
in these tunnels to build this
instrument. Um, and they're measuring
they're they're trying to record the
wobbling of spaceime right as it passes
this sort of undulation. Uh, that
amounts to less than
110,000th the variation in a proton over
the four kilometers. It's an insane
insane achievement. Oh, great
engineering. I don't know how they did I
swear I follow them around from so I
just for fun I'm I'm very theoretical. I
don't build things. I'm always super
impressed that people can translate
something on the page and and it looks
like wires and I don't know how I'm
always surprised at what it looks like
and but I walked the tunnels with Ray
Weiss who won the Nobel Prize along with
Kip Thorne and Barry Barish one of the
project managers and I walked the
tunnels with Ray. It was a delight. I
mean Ray is one of the most delightful
people. Kip is one of the most wonderful
people I've ever known. Um, and uh, Rey
said to me, you know, the reason why it
was called Black Hole Blues is because
about a month before they succeeded, he
said to me, if we don't detect black
holes, this whole thing's a failure.
And, um, we've led this country, you
know, down this wrong path. And, um, he
really felt like this tremendous
responsibility for this project to
succeed. And it weighed on him, you
know, it was uh it was just quite
tremendous what the the integrity,
right, the scientific integrity. And the
first instruments he built, he was
building outside of MIT and on a
tabletop and his his colleagues said,
"You're not going to get tenure, you
know, you're never going to succeed."
Um, and they just kept going. People
like that. So huge teams, huge
collaborations are just uh is how the
world moves forward because it's an
example. It's you know there's building
cynicism about bureaucracies when a
large number of people especially
connected to government can be
productive. You know bureaucracies slow
everything down. So it's nice to see an
incredibly unlikely exceptionally
difficult engineering project like this
succeed. Oh yeah. So I I understand why
there's this weight on his shoulders and
I'm great there's I'm grateful that
there's great
leaders that push it forward like that.
Yeah, it really is. You see so many u
moments when they could have stumbled.
Yeah. Um and they built a first
generation machine just after 2000 and
it wasn't a surprise to them but it
detected nothing. Crickets. Crickets.
And they just, you know, they have the
wherewithal to keep going. second
generation. They're about to turn the
machine on, quote unquote. You It's a
little bit of a simplification, but do
their first science run and they decide
to postpone um because they feel they're
not ready yet. It's September 14th in
2015 and the experimentalists are out
there. They're in the middle of the
night, you know, they're working all
night long and they're they're banging
on the thing, you know, literally
driving trucks, slamming the brakes on
to see the noise that it creates. And um
so they're really messing with the
machine, really interfering with it just
to kind of calibrate how much noise can
this thing tolerate. And I guess the
story is is they get tired. There's
there's an instrument in Louisiana and
there's one in Washington state. And
they go home, put their tools down, they
go home. It's um they leave the
instrument locked though, mercifully.
And um it's something like within the
span of an hour of them driving back to
their humble abodess that they have in
these remote uh regions where they built
these
instruments, this gravitational wave
washes over, I think it hits Louisiana
first. It travels across the US, brings
the instrument in Washington state. It
began, you know, over a billion and a
half years ago before multisellular
organisms had emerged on the earth. Just
imagine this from like a distant view,
this collision course, right? And um
it's the centenerary. It's it's it's the
year Einstein published general
relativity. That's so it was this, you
know, a hundred years. I mean, just
think about where that where that signal
was when Einstein in, you know, 1915
wrote down the general theory of
relativity. It was on its way here. It
was almost here.
Uh, what do you think is cooler? Uh,
Einstein's general relativity or LIGO.
Well, I can't disparage my friends, but
of course, relativity is just so
all-encompassing. No, but see, so hold
on a second. All-encompassing, super
powerful leap of a theory. Yeah. And
they built it. They built it. I don't
know, man. the greatest engineering on
the in the you know cuz I I don't know
cuz
you know yeah humans getting together
and building the thing that's really
ultimately what
uh what impacts the world right yeah uh
I mean I I just as I said my admiration
for for Ry and Kip and the entire team
is is enormous and you know just
imagining Rey had been out there on site
he had just left to go back home um
wakes up in the middle night and sees
it, you know, can you imagine? And
there's a signal, you know, there's
something in the log. He's like, "What
the hell is that?"
So, speaking of the human story, you uh
also wrote the book A Mad Man: Dreams of
Touring Machines. It connects two
geniuses of the 20th century, Alan
Touring and Girdle. What specific
threads connect these two minds? Yeah, I
was um was really mesmerized by these
two characters. They people know of Alan
Turing for having
ideiated about the computer being the
person to really imagine that. But his
work began with thinking about God's
work. That's where it began and it began
with this phenomenon of undecidable
propositions or unprovable propositions.
So um uh there was something huge that
happened in mathematics which is people
imagined that any problem in math could
technically be proven to be true.
doesn't mean human beings are going to
prove every fact about everything in
mathematics but you know it should be
provable right I mean it seemed kind of
it's not that wild supposition and
everyone believed this all the great
mathematicians Hilbert was a call of his
to prove that and go to a very strange
character
uh very unusual he he was a platonist he
he literally believed that mathematical
objects had a existential reality he
wasn't so sure about this reality. This
reality he struggled with. He he was
distrustful
um a physical reality but he absolutely
took very seriously a platonic reality
and often his own way of thinking and he
proved that there were facts even among
the numbers that could never be proven
to be true. You have to think about that
how wild that is that even a fact about
numbers seems very simple uh could be
true and
unprovable could never exist as a
theorem for instance in mathematics
unreachable
um this incompleteness result was very
disturbing essentially it's equivalent
to saying there's no theory of
everything for mathematics it was very
disturbing to people but it was very
profound and Alan Turing
got involved in this because he was you
know he was thinking about uncomputable
numbers. So um and that led him what's
an uncomputable number? A number like
0.175. It just goes on forever with no
pattern and I can't I can't even figure
out how to generate it. There's no rule
for making that number. And he was able
to prove that there were such things as
these uncomputable effectively
unknowable numbers. That might not sound
like a big deal was actually was
actually actually really quite profound.
He was relating to godal intellectually
right in the space of ideas. But he goes
a very different path almost
philosophically the opposite direction.
He he he builds he starts to to think
about machines. He starts to think about
mechanizing thought. Starts to think
what is a proof? How does a
mathematician reason? What does it mean
to reason at all? What does it mean to
think? And he begins to imagine
inventing a
machine that
will execute certain orders, you know,
mechanize thought in a specific way.
Well, maybe I can get a machine. I can
imagine a machine that does this kind of
thinking and that he can prove that even
a machine could not compute these
uncomputable numbers. But where he ends
up is the idea of a universal machine
that computes. Um, essentially can take
different software and execute different
jobs, right? We don't have a different
computer to connect to the internet than
we do to write papers. It's one machine
and um, one piece of hardware, but it
can do all of these this huge variety of
tasks. And so he really does invent the
computer essentially. Um, and famously
he uses that thinking in a very
primitive form in the war effort where
he's recruited to help break the German
enigma code. Um, which is heavily
encrypted and largely believed to be
uncrackable code. and um and and people
believe that Turing and his very small
group actually turned the tide of the
war in favor of the allies precisely
um by using a combination of this
thinking and just sheer ingenuity and
some luck. Um but uh but the other
profound revelation that Turring has is
that well maybe we're just
machines right and uh just biological
machines and this is a huge shift for
him. feels very different from God who
doesn't really believe in reality and
thinks numbers are are platonic
realities and and Turing kind of
thinking we're kind of like we're
actually machines and we could be
replicated.
So of course Turing's influence is still
widely felt on many levels. So as to the
on many levels yeah in complexity
theories theoretical computer science
and mathematics but also in philosophy
with his famous touring test paper. So
like you said conceiving like what what
is the connection that I guess Ger never
really made between mathematics and
humanity
uh touring did but I think there's
another connection to those two people
is that they're both in their own way
kind of tormented yeah humans. I think
they were very tormented. What aspect of
that contributed to who they are and
what ideas they developed? I mean I
think so much. I don't I don't want
to promote the kind of trit trope of the
mad genius, you know, if you're
brilliant, you are insane. I don't think
that. I don't think if you're insane,
you're brilliant. Um but I do think if
somebody who's very brilliant who also
chooses not to go for regular
gratification in life Mhm. they don't go
for money. They don't necessarily
value creature comforts. They're they're
not leveraging for fame. I mean they're
really after something different. I
think that can lead to a kind of runaway
instability actually. Yeah. sometimes um
they're already outside of kind of
social norms. They're already outside of
normal connections with people. They've
already made that
break. Um and I think that makes them
more
vulnerable. So God, you did have a wife
and an strong relationship as far as I
understand and had a was a successful
mathematician and ended up at the
Institute for Advanced Study where he
walked with Einstein to the institute
every day. Um and they talked about and
he proved certain really unusual things
in relativity. You you made reference to
these rotating galaxies. We were talking
and actually Goodel had a model of a
rotating universe that you could travel
backwards in time. It was mathematically
correct. Showed Einstein that within
relativity you could time travel. Um
just a unbelievably influential and
brilliant man. But um he was probably a
paranoid schizophrenic. Um he did have
breaks with reality. Um he uh was I
think quite distrustful and feared the
government feared his food was being
poisoned and you know
ultimately literally starved himself to
death. Um
and it's such an extreme
outcome for such a fil mind you know for
for such a brilliant mind. I think it's
important to sort of not to glorify or
romanticize madness or or um suffering,
but to me, you can flip that around and
just be inspired
by the peculiar maladies of a of a human
mind, how they can be leveraged and
channeled creatively. Oh yeah. I think a
lot of us obviously probably every human
has those peculiar qualities.
You know, uh I talk to people sometimes
about just my own psychology and I'm
extremely self-critical
and uh I'm drawn to the beauty in
people, but because I make myself
vulnerable to the world, I can really be
hurt by people and that thing. Okay, you
can lay that out. That's this particular
human. Okay.
And you know, there's a bunch of people
that will say, well, you many of those
things you don't want to do. Mhm. Maybe
don't be so self-critical. Maybe don't
be so open to the world. Maybe have a
little bit more reason about how you
interact with the outside world. It's
like, yeah, maybe. Or maybe be that and
be that fully and channel that into a
productive life into we're all going to
die
in the time we have on this earth. Make
the best of the
particular weirdness that you have. Mhm.
And maybe you'll create something
special in this world and in the end it
might destroy you. And I think a lot of
these stories are that it's not that Oh
yeah. It's not like saying, "Oh, because
uh in order to achieve anything great,
you have to suffer." No. If you're
already suffering Mhm. if you're already
weird, if you're already somehow don't
quite fit in your particular
environment, your particular part of
society, use that somehow. I use the
tension of that, the friction of that to
create something. I mean that's what I
you know um ner who suffered a lot from
even like stupid stuff like stomach
issues like oh yeah kind of right
migraines is like psychosmatic or
psychophysical but and all those that's
the real it's like
that can somehow be
channeled into a productive life. It's
it should be inspiring. A lot of us
suffer in different ways. Yeah. I'm a
big believer in the tragic flaw.
Actually, I think the Greeks really had
that right. Um, you're describing it.
What makes us great is ultimately our
downfall. Maybe that's just inevitable.
The choice could be not to be great.
Um, and I guess I I that's sort of what
I mean by they had already broken from a
traditional path because they decided to
pursue
something so elusive and um that would
isolate them to some extent
inevitably and that could fail, right?
And whose rewards were hard to predict
even. Um, and I do think that that all
the character traits that went into
their
accomplishments were the same traits
that went into their demise. And um, I
think you're right. You could say, well,
you know, Lex, maybe you should not be
so
empathetic, hold yourself, cut yourself
off a little, but protect yourself,
right? But isn't that exactly what
you're bringing? one of the elements
that you're bringing that makes
something extraordinary in a space that
lots of people try um to break through.
Yeah. And but we should mention that for
every girl on touring, there's millions
of people who have tried and who have
destroyed themselves and without without
reason. I would find it impossible
to not pursue
uh a discovery that I could I could
imagine my way through. If I can really
see how to get there, I I cannot imagine
abandoning it for some other reason. Uh
uh fear that it would be misused, which
is a real fear. Mhm. Right. I mean, it's
a real concern. Um I don't think in my
work since I'm doing extra dimensions in
the early universe, but or black holes,
you know, I feel pretty safe. But I
mean, who knows, right? Bore couldn't
think of a way to use quantum mechanics
to kill people. Mhm. Um I cannot imagine
pulling back and saying, "Nope, I'm not
going to finish this." You know, I'll
give you a counter example of an
exceptionally brilliant person. Terrence
Tao, brilliant. Brilliant mathematician.
Brilliant. Mhm. He is better than out of
all the brilliant people I've ever met
in the world. He's better than anybody
else at
working on a hard problem and then
realizing when it's for now a little too
hard. Oh, that I can do. and stepping
stepping away and he's like, "Okay, this
is now a weekend problem." Uhhuh. Cuz he
has he has seen too much for him.
Everybody's different, but Gregori
Pearlman Mhm. or Andrew Wilds who who
give themselves a great story completely
for many years over to a problem. Yes.
And for every every Gigor and they might
not have cracked it. Yep. So you choose
your life story like I totally agree.
Now I'm not going to say sometimes I
take too long to come to that conclusion
but I will proudly say as most
theoretical physicists should that I
kill most my ideas myself. Okay. So, you
walk away. I am absolutely able to say,
"Ah, that's just not I mean, I'm not
going to deny that sometimes I maybe
take a while to come to that conclusion
longer than I should, but I will I
absolutely will. I will drop it." And
that is that is any self-respecting
physicist should be able to do that. The
problem is with somebody like Andrew
Wilds, you were describing who to prove
last theorem, it took him seven years.
Was that the number? Something like
that. he went up into his mother's attic
or something and did not emerge for
seven years is that maybe he did he was
on the right track. He wasn't wrong and
and but that's so it could have been
interminable. He still might not have
gotten there in the end and and so
that's the the really difficult space to
be in uh where you're not wrong, you are
on to something, but it's just asically
approaching that solution and you're
never actually going to land it. Um that
happens and he had a really I it would
break me straight up break me. He had he
had a proof. Yes. He announced it and
they somebody found a mistake in it.
That would just break me. Yeah. Because
you now everybody gets excited, right?
And now you you you realize that it's a
failure and to go back taking a year for
people to check it. It's not the kind of
thing you look over in an afternoon and
then to to have the will to have the
confidence and the patience to go back.
unbelievable rigorously go through work
through it. It's a great story. But then
there's another great story, Gregori
Pearlman, who uh spent seven years he
and turned down the Fields Medal. He did
it all alone. And then after he turned
on the Fields Medal and the Millennial
Prize, proving the porn conjecture, he
just walked away. Yeah. Now that's a
very different psychology. That's wired
differently. Doesn't care about money,
doesn't care about fame, doesn't care
about anything else. Yep. In fact, where
is he now? Uh in St. in Petersburg,
Russia trying to trying to get a
conversation with him. It turns out when
you walk away and you're a recluse and
you enjoy that, you also don't want to
take some weird dude in a tie. So, turns
out I'm trying. I'm trying. Well, if you
look at someone like
Tarring,
his his eccentricities were were
completely different, right? It's not as
though there's some mold. And I I really
don't like it when it's portrayed that
way. These are really individuals who um
who were still lost in their own minds
but in very different ways. And Turring
was openly gay really um during this
time. You know, he was working during
the war, World War II, so we understand
the era and it was illegal um in Britain
uh at the time. and he kind of refused
to
conceal himself.
Um there was a time when the kind of
attitude was, well, we're just going to
ignore it. But he had been robbed by
somebody that he had picked up
somewhere. I think it was in Manchester.
And it was such a small thing. I don't
know what they took. It took like
nothing, you know? It was nothing. But
he he couldn't tolerate. He goes to the
police and he tells them and then he's
arrested. He's the criminal because it
involved this homosexual act. Now here
you have somebody who made a major
contribution to the allies winning the
war. I mean it's just unbelievable. Not
to mention the genius mathematical
genius. I mean he saved the lives of the
people that were doing this to him and
they essentially chemically castrated
him as as a punishment. That was his
sentence. And he became very depressed
and suicidal. And um the story is he was
he was obsessed with Snow White, which
was recently released. And he used to
chant one of the uh little I don't know
if you would call them poem songs. Uh
dip the apple in the brew, let the
sleeping death seep through was a chant
from Snow White. And um the the belief
is is that he dipped an apple in cyanide
and bit from the poison apple. Now I
don't know if this is apocryphal, but
people think that the apple on the
Macintosh with the bite out of it is a
reference to Turring. Now some people
deny this. That's nice. That's nice. Um
but uh some people say he did that so
his mother could believe that maybe it
was an accident,
but yeah, quite a terrible end. Yeah.
but to two of the greatest humans ever.
I think the reason why um I I tie them
together, not just because ultimately
their work is so connected, but but
because there's this sort of
impossibility of understanding them,
there's this sort of impossibility of
proving something about their lives that
even if you try to write factual
biography, there's something that eludes
you. And I felt like that's kind of
fundamental to the mathematics. the
incompleteness, the undecidable, the
uncomputable. Yeah. Um, so structurally
it was it was about what we can kind of
know and what we can believe to be true
but can't ever really know. Yeah.
Limitations of formal systems,
limitations. Exactly. Biography,
limitations of fiction and non-fiction.
Limitations. So you I there's so many
layers to you. So one of which there's
this romantic notion of just
understanding humans exploring humans
and there's the exploring science there
exploring the very rigorous detailed
physics and cosmology of things. So uh
there's art the kind of artistry. So I I
I saw that you're the chief science
officer of Pioneer Works which is mostly
like an artist type of situation. It's a
place in Brooklyn. Can you explain to me
what that is and what role does art play
in your life? Yeah, I can start with
Pioneer Works. Pioneerics in some sense
it was inevitable that I would land at
Pioneerics. It felt like I was marching
there for many years and and just it it
came together again like at this
collision. Um it was founded by this
artist Dustin Yellen. Very utopian idea.
He bought this building this old iron
works factory called Pioneer Iron Works
in in Brooklyn. was in complete
disrepair, but a beautiful old um
building uh from the late 1800s. And he
wanted to make this kind of collage.
Dustin's definitely a collage artist.
Works in glass, very big pieces, very
imaginative and and wild and narrative
and into nature and consciousness and
and I think he wanted to do that with
people. He wanted a place of a collage,
a living example of artists and
scientists. And it was founded by Dustin
and and Gabriel Florence was the
founding artistic director. Um, it it
was started just before Hurricane Sandy.
I don't know if people feel as strongly
about Hurricane Sandy as New Yorkers do,
but it was a real moment around 2012,
2013. Sort of paused the project and you
can even see the kind of waterline on
the brick of where Sandy was. I came in
and collided with these two uh shortly
after that and it really was like a
collision. I'm science, you know, their
art. Gabe makes everything, builds
everything with his bare hands. Dustin's
a dreamer. They love science. They
really wanted science, but science is
hard to access. Um I have always loved
the translation of science in
literature, in art. Uh, I love fiction
writers, like really literary fiction
writers who dabble thinking about
science. And I I I I very firmly believe
science is part of culture. I just I
know it to be true. I don't think of
myself as doing outreach or education. I
I don't like those labels. I'm I'm doing
culture.
an artist in their uh studio working out
problems, understanding materials,
building a body of work. Nobody says to
them when they exhibit, why are you
doing outreach or uh or are you doing
education? You know, it's the logical
extension.
So I feel that if you've had the
privilege of knowing some of these
people, of seeing a little bit from the
summit, if you've had a little glimpse
yourself, that that you bring it back to
to to to the world. So we boom exploded.
Pioneerics became science and art. It's
not artists who all do science or
scientists who do art. It's real
hardcore scientists talking about
science and a lot of live events. We
have a magazine called Broadcast where
we feature all of the disciplines
rubbing together artists working on all
kinds of things. When I first started
doing events there, my my first guest um
like you, I was talking to people and
this was like I know how to talk to
people because I know these guys and
I've been on the interviewe side so much
I know exactly it was like fully formed
for me how to do those conversations.
Yeah, you're extremely good at that
also. Yeah, thank you. I appreciate
that. I You learn how to do it too
though. I mean, I don't think the first
one I did. I think I've learned, right?
And you acquire, you get better. It's
really interesting. Um, and I love to
study. I think you do, too. I really
look into the material and that and I I
love science. I really do. I want to
talk to a crisper biologist because I
don't understand it and I want to
understand it. And I saw there's a bunch
of cool events and very very fascinating
variety of humans. Yes, we have a really
fascinating variety of humans. That's a
good way of putting it. Yeah. So, it
made me put in my mental map of like
it's a cool place to go and visit when
in New York. Yes. You have to come see
us. I think you would love it. Also, I
should mention fashion. I've seen you do
a bunch of talks and there's there's a
lot of fashion. Yeah. Oh, appreciation
of fashion going on. I am so you're
giving me an opportunity to give a shout
out um to Andrea Lara who's a designer
who makes these amazing jumpsuits that I
often wear in a lot of my events. She
has a jumpsuit um design line called
Risen Division and she just makes these
incredible. They're fantastic. We also
design patches for all of our events. So
there are these string theory patches
and consciousness patches and we should
show this as overlays. Hopefully
there'll be nice pictures floating about
everywhere. So, you know, I think all of
this is is just I just like to
experiment with life. I think making the
magazine was a big wild experiment. You
said with life. With life. Nice. Yeah.
Um this kind of idea that we were just
describing is I I I find it hard to stop
the momentum if I think something can I
can make something. Um I have to try to
make it. Um, and to me this is the
closest I come to experimentation and
collaboration because even though I I
collaborate theoretically, I have great
collaborators, Brian Green, Masimo
Paratti, Dan Kat, these are my really
close collaborators. Um, a lot of
theoretical physics is alone and you're
in your mind a lot. Um, this is
something that really was was was built
this triad of Dustin, Gabe, and I and
all our amazing people who work there
and our amazing board. we really are
doing it together. You take one element
out and it starts to um it starts to
change shape and that's a very
interesting experience I think and
making things is an interesting
experience. Since you mentioned
literature, is there is there books that
had an impact on your life, whether it's
literature, uh, fiction, non-fiction.
I love fiction, which I think people
expect me to read a lot of sort of
sci-fi or non-fiction. I mostly read
fiction. I had a syllabus of great
fiction writers that had science in it
and um, I love that syllabus. Can you
ever make that public or no? Yeah, I
suppose I could, but I can tell you some
of them as they come to mind. Um, Katsu
Ishiguru, who won the Nobel Prize, wrote
Remains of the Day, probably most
famously. Um, his book Never Let Me Go,
it's unbelievable, totally devastating,
stunning. I see. I really love
literature. So, when when people can do
that with these very abstract themes,
um, it's sort of my favorite space for
for literature. Martin Amos wrote a book
that runs backwards, Times Arrow. I love
some of his other books even more, but
Times Zero is pretty clever. So, you
like it when uh these non-traditional
mechanisms are applied to tell a story
that's fundamentally human that there's
some Yes. some beauty of language like I
really appreciate that. Even Orwell is
amazing. You know, Hitchens writing on
Orwell is amazing. Um there was there
were some plays on the syllabus. I have
to think of what else was in there. But
there was one book that I think was kind
of surprising that I think is an
absolute masterpiece which is the road.
And you might say in what sense is the
road to science? Well, first of all,
Cormick McCarthy absolutely loves
scientists and science. And you can feel
this very subtle influence in that book
is um it's it's
an remarkable
uh precise, stunning, ethereal, all of
these things at once. And there's no
who, what, where, when, or how. Um, you
might guess it's a nuclear event that
kicks off the book or a lot of people
know the road I I think from the movie,
but really the book is magnificent. Um,
and it's very very abstract, but there's
a sense to me in which it is science is
structuring the and still fundamentally
that book is about the human story, the
human connection. Boy, yeah. So, the
science plays a role in creating the
world and within it there's still really
it's it's a it's a different way to
explore human dynamics in a way that's
maybe land
some clarity and depth that maybe a more
direct telling of the story would not
Yeah. Yeah. even surreal worlds that I
mean to me I don't know why but um I
return to Orwell's Animal Farm a lot and
there's these kind of like
it's another art form to be able to tell
a simple story with some surreal
elements. Mhm. Yeah. Well, just simple
language. Mhm. Oh, animal form is
incredible. And in fact, some of the
I've kind of played with you know some
animals are more equal than others.
There are there are in good old
Turring's work there were some
infinities that are bigger than others.
Yeah, there certain books just kind of
inject themselves into our culture in a
way that just rever reverberates and
uh I don't know hasn't creates culture
not just like influences. It's just like
it's quite incredible how writing and
literature can do that. Yeah. If you
could have one definitive answer to one
single question. This is the thing I
mentioned to you. So hard. Yeah. Well,
there's a there's an oracle and you get
to talk to that oracle. You can ask
multiple questions, but it has to be on
that topic. So, just clarify. What What
mystery of of the universe would you
want that oracle to help you with? You
know, it's funny. I should say the
obvious thing and but I feel like I
almost feel like it would be greedy. I I
think I have a complicated response to
this. The obvious thing for me to say
would be I want to understand quantum
gravity or if gravity's emergent. Um
it's not even something I work on
daytoday. You know I I mostly
just look with interest at what others
are doing and if I think I can jump in I
would but I'm not jumping into the fray.
But obviously that's the big that's the
big one and and there is a sort of sense
that with that will come the answers to
all these other things. My complicated
relationship is that well, you know,
part of the scientific disposition isn't
having stuff you don't know the answer
to. I mean, we're not going to have all
the answers. I hope because then sort of
then what, right? It's sort of
dystopian. I totally agree with you.
There's some I like the mysteries we
have. Yeah. Uh I kind of had this
assumption that there will always be
mysteries, so you want to keep solving
them. They will lead to more. In the
same way that relativity led to black
holes, black holes led to the
information loss paradox or the big bang
or what happened before or the
multiverse. It's because we learned so
much we were able to escalate to the
next level of abstraction. Yeah. Yeah,
by the way, we should mention that if
you're talking historical and even if
you ask the obvious question about
quantum gravity, I almost guarantee with
100% probability
that even if all your questions are
answered, it's impossible to get to the
end of your questions because it says um
you know Oracle will say no, you can't
unify.
But then you say well wait yeah yeah
yeah and then you say emergent and then
the or you know Oracle say well uh
everything you think is fundamental is
not it's emergent. It's like okay well
this is this is we need to more
questions right I mean it's been a
hundred years more since relativity and
we're still picking it apart. Yeah. No
and there will be there may be new ones.
Mhm. You write that eventually all our
history in this universe will be erased.
M how does that make you feel?
Yeah, that's a tough thought. But again,
I think there's a way in which we can
come to terms with that that that's kind
of poetic. You know, you build something
in the sand and then you erase it.
Yeah. So, I think it's just a reminder
that we have to be concerned about our
immediate experience too, right? how we
are to those around us, how they are to
us, what we leave behind in the near
term, what we leave behind in the long
term, have we contributed and and did
we, you know, did we contribute overall
net
positive?
Um eventually I think it's kind of hard
to imagine but yes all of these Nobel
prizes all of these mathematical proofs
all of these conversations all these
ideas all the influence we have on each
other even the AI
eventually will expire.
Well at the very least we can uh focus
on drawing something beautiful in the
sand. Yeah. Before it's washed away.
Well, this was an incredible
conversation. I'm truly grateful for the
work you do and me for your work. Thanks
so much for having me. Thank you for
talking today. Yeah, lots of fun. Thanks
for listening to this conversation with
Channel 11. To support this podcast,
please check out our sponsors in the
description. And now, let me leave you
with some words from Albert Einstein on
the topic of
relativity. When you're courting a nice
girl, an hour seems like a second. When
you sit on a red hot cinder, a second
seems like an hour. That's
relativity. Thank you for listening and
hope to see you next time.