 And now it is my distinct pleasure to welcome Jenna Levin who is the Professor of Physics at Barnard College of Columbia University and also the Director of Sciences at Pioneer Works. Please. Yeah. It's so nice to be here. When I spoke to the organizers, when I was invited, I asked them, what would you like me to speak about? And they said, you know, you should talk about space and your research and also maybe art and design and maybe what you're up to in Brooklyn. And I was like, oh, OK, no problem. No problem. So this talk is, I'm hoping to really reach from the Big Bang to Black Holes to Brooklyn. And I want to kind of use a rallying theme around the idea of light and the constraint of light. This is something I'm sort of personally semi-obsessed with. The idea that an incredibly rigid constraint. Using as absolute and unyielding as the absolute nature and constancy of the speed of light leads to essentially a revolution in another direction. So the idea almost like squeezing a balloon in one direction and it expands in the other. And I think that this is true both in science and in art and in design and in aspects of culture. And so I want to kind of use this as a thread to weave through. So let's start with the constancy of the speed of light. We'll see how this goes. So famously, Maxwell, the end of the 1800s, wrote down his theory of electromagnetism, the beautiful mathematical model, first example of unification. And in this fundamental law of physics, there are these waves, electric fields, magnetic fields, these beautiful oscillating waves. And they have, as a fact of nature, a fundamental constant, which is the speed of light. These are light waves. And they have a speed that is set by the laws of nature. I know I'm being repetitive, but it's on purpose. Think of how odd that is. There is nothing whose speed is a fact of nature, right? The speed of a car is not a fact of nature. It can go slower. It can go faster. It can stop. Light cannot slow down. It cannot speed up. It cannot stop. It has one speed of roughly 300,000 kilometers per second. Now when this was discovered, nearly everybody in the entire physics community said that's just not possible. And here comes Einstein, who's a very young physicist. He can't get a job. His teachers call him a lazy dog. He said about himself, when I was a student, I was no Einstein. So here he is working in a patent office in Bern, Switzerland, where he has what he calls the physics department, which is a drawer in his desk, where he's working on the laws of physics. And he begins to meditate on this idea. And what I want to emphasize is what comes out of it is the theory of relativity, but it could have been called the theory of absolutism, because it began with his adherence to the absolute rigidity of the speed of light as a fact of nature. So while everyone else is scrambling to undo it, he respects it and asks what it means. So let's imagine what it means. So here's my astronaut. This is Alice. She's floating in empty space. I'm lucky to be here with astronauts today, so I love to ask them about their experience floating in space. It is a pretty odd experience. I can imagine. And here's Alice. She's floating in empty space. You could ask her, are you moving Alice? And she would say, she would look around. She would not really notice anything. She'd say, no, I'm not moving. Then on the horizon, she sees in the distance Bob. And there goes Bob. Bob goes scooting by. And she goes, Bob, you're moving. You're the one who's moving. But imagine from his perspective, here's Bob. And this is what he sees. Same experience, but he says, no, Alice, you're the one who's moving. So who's moving? Alice or Bob? This principle of relativity dates back to Galileo. It long predates Einstein. Einstein took it so seriously. He said it is crucial that neither one of them is preferred. Why would the laws of nature pick Alice or Bob to be the one moving? Motion is relative. There is no absolute answer to that question. It's really quite profound. There is no experiment either Alice or Bob could perform that would tell them which one of them is the one that's really moving. It's meaningless. Motion is relative. So now let's introduce the speed of light. Here's Alice and she's shooting out light beams and she's saying, ah, they're moving. At 300,000 kilometers per second, I know this because of Maxwell's fundamental law of nature. It's a fact of nature. I got the speed right. But Bob should have the same experience, right? Because Bob doesn't know if he's moving or if Alice is moving. So here she does a final experiment and Bob comes cruising by, OK? And it seems like he should see light coming at him faster because he's racing at these light pulses. But if you ask Bob, what did you measure for the speed of light? He's going to say 300,000 kilometers per second. It's extraordinary. It is surreal. It is bizarre. And you can see why all the physicists of the time fought it. Now what Einstein said is, look, speed is really distance over time. So if I'm going to yield, give in to the fact of the limit of the speed of light, then there must be something different about space and time than the way we usually think about it. And here's Bob again. He's traveling in time, but not in space. He thinks he's standing still. So if he were to try to make a map of space and time, he would say, yes, I moved forward in time. I felt my breath move. I watched my clock. But I didn't move in space. And when he thought about his experience with Alice, he would say, you know, Alice, I only moved in time, but you moved in both space and time. Now if we go to Alice's perspective, she would say, let's freeze it for a second. Wait a minute. I'm the one who's not moving. So I'm the one who's only moving in time. And in some profound sense, Einstein thought Alice's time is rotated relative to Bob's. Space and time are not the same for them. They must be measuring in some subtle way a different direction for time, much like you might argue for a different direction for left. We know left is relative and we're not surprised. And we know that my left and your left is roughly rotated by 180 degrees from each other. Similarly Alice and Bob experience a rotation in space and in time. Now it's hard to draw it on a flat sheet of paper. We call this Euclidean space. We now understand that an empty space, what we have is what's called a Minkowski space and that the rotation in space and time is very well understood in that space. So we're saying a map of the round earth is slightly distorted when we put it on this flat screen while a map of space and time is slightly distorted when we put it on this flat screen. So here comes Einstein with this idea that space and time are relative. They can be rotated into each other. Alice measures a different passage of time on her clock than Bob does. They biologically experience a different time. And after 10 years they elevate this to the general theory of relativity which despite the severity of the constraint we started with leads to this revolutionary view of the world. So here is a digital atlas of the known universe. Every object in here has been observed. It's not a cartoon. It's a map that's put together of all of the observations to the best of our knowledge at that point in time so that we can move out through the universe. We're now panning away from the solar system. And this is the legacy of the theory of relativity. The understanding that even though that's the distance light has been able to travel since we sent the first intentional signals into space. There goes our entire galaxy, 100 billion stars. All of this comes subsequent to relativity. Everything you're seeing in this sky right now is itself an entire cluster of galaxies. And right now we're all the way back to the furthest reaches where light has been able to come to us, light from the Big Bang itself, the light left over from the Big Bang. Now we're cruising back in here, and we're coming back to our Milky Way galaxy. And that entire idea of a Big Bang, the expansion of spacetime, the idea that there are other galaxies out there, that they affect the way that we perceive the universe, that when we look back into space, deep into space, we're actually looking back in time, all of that explodes like a revolution out of the adherence to this one constraint. And so that is now the world that we live in where we see it as this vast and unbelievable warped spacetime. Now even though I've shown you all of that, the known universe, that's essentially everything we've been able to observe thus far, it's amazing that that makes up less than 5% of what's out there. So in other words, anything anyone has ever seen, ever, and ever will see in the history of the universe, since Galileo forward makes up less than 5% of what's out there. What's extraordinary is that what comes to us from light is very little. Most of the universe is dark. Most of the universe is in a form of matter called dark matter, a form of energy called dark energy. These are just proxies. These are just random names, signatures, monocles we give to mean we have no idea what that thing is. So most of the universe is in a form of matter and energy that we might as well throw our arms up and say we just don't know what it is. And that's quite extraordinary. But the fact that we know it is only because of how precise we understand everything so we can extrapolate the missing signals, the signals that you cannot see. You might as well call these things also invisible. So dark matter is technically a form of invisible matter. Right now, there are neutrinos from the sun passing through your body, passing through all of this, and the reason it passes through is precisely because it doesn't interact with light. It is invisible to you. It is a form of dark matter. It's just not able to explain the dark matter that we see on the cosmic scales. And presumably, we're all floating in this dark energy. If we could see it, we would be in a kind of storm, a dark energy storm. But we cannot, so it's invisible to us. Now, in the dark sector, my favorite aspect of the dark sector is black holes. And they might be the smallest of the dark sector. But these are another extraordinary consequence of Einstein's theory of a relative space and time and a curved space and time. And black holes you might think of as a dense crush of matter. But I really want you to think of them as nothing. Black holes are actually empty spacetime. They're more like a place than they are a thing. If you were an astronaut floating around a black hole and you were to cross into this shadow, this is the region beyond which not even light can escape the event horizon. You would find that there is nothing there. It would just be empty. You would sail across fairly unharmed. You would float for another microsecond or so. And you would watch the entire galaxy evolve over millennia, seeing the light spill on top of you so it's dark outside the black hole, but not inside. And then you'd be crushed to death in the singularity. But it's not a bad way to go. I mean, if you're going to go, it's not a bad way to go. If you were to try to shoot a light beam at that horizon, it would race out at the speed of light because that can never change. But it would never escape from the black hole. And that seems also to be counterintuitive. But essentially, you have to think of the spacetime of the black hole as raining down inward, almost like a fish swimming upstream against the Niagara. It still falls into the black hole. And a little light pulse would effectively stay right there as it tried to race out and the spacetime rained in. Now, black holes are real. We know that they exist. But we've never taken a picture of a black hole. Here's a little tiny black hole. Everyone thinks black holes are these monsters and they're terrible, huge, destructive. Actually, black holes are tiny. That's the whole point. If you took the entire sun and you crushed it to a black hole, it would be about six kilometers across. It would fit inside Manhattan. It's a tiny little thing. And so if you try to see a black hole, try to see this shadow against the bright galaxy that we live in, it's hopeless. It's utterly hopeless. We have never taken a picture of a black hole. We've seen them indirectly by the havoc that they wreak on the environment around them. But we have never, at least not yet, taken a picture of the shadow of a black hole. There's a fantastic project called the Event Horizon Telescope, which is going on here in Cambridge. The principal investigator, Shep Doliman at Harvard. And they're trying literally to take a picture of the shadow of the biggest black hole that's closest to us. It's a few million times the mass of the sun. It's about 26,000 light years away. It's in the center of our galaxy. We call it Sagittarius A star because it's in the direction of the constellation Sagittarius. And resolving, even though it's millions of times the mass of the sun, it's only about 20 times as big across. So they liken it at 26,000 light years to resolving a piece of fruit on the moon. That's how hard the project is. And they're using all of these telescopes around the entire Earth in concert to make it like one big eye, one big telescope. And Event Horizon Telescope is imminent. It's imminent the results from that. But that would be the first picture ever taken. So we could say, well, we are limited by light. Black holes are dark by definition. They emit no light. They reflect no light. What else could we do with black holes? And it's this extraordinary idea that, again, dates back to Einstein, that, well, if an object can curve space and time around it, and if it moves, let's say I have two black holes in orbit around each other, then the curves in the shape of space must move with them. It has to follow them. And it has to follow them slower than the speed of light because nothing can travel faster than the speed of light, including the information in the shape of space and time. So these are called gravitational waves. These ripples literally in the shape of space and time. If you were nearby two black holes colliding, you would kind of bob on the wave. It's possible that the changing shape of space and time would literally squeeze and stretch your ear mechanism that you would hear it even in the vacuum of empty space, that it would be a sound. It is not light. It would be a sound. And this idea, again, which dates back to Einstein, was really controversial. Einstein would write papers saying gravitational waves exist. They would get accepted for publication. And then he would pull the paper and submit another one to go to press that said that the opposite conclusion. And this went on for decades. Along comes a young scientist, Ray Weiss, in the 1960s. And he decides, you know, I'm just going to have a listen. Nobody knows if black holes are real. We've never seen a black hole. Einstein was still arguing about whether or not gravitational waves were real. What if I tried to go out and just have a listen? And he imagined building a kind of cosmic recording device. And he called it a haiku. He said nobody would have thought it was of any interest. And he was working in building 20 on the periphery of the MIT campus right here. It was also known famously as the Plywood Palace, a place of such unbelievable creativity. I think it was nine Nobel prizes came out of this shoddy ramshackle structure that was supposed to be thrown up for five years at most during the war effort to encourage investment in science. And it lasted for 50 years, nine Nobel prizes later. They finally tear it down in 1998. And the building was supposed to be so inspiring precisely because nobody cared what they did in there. They would knock out windows. They would steal each other's electricity. They'd puncture holes in the ceiling. They blew holes in the roof. And they shot atoms out the top of the building. Didn't matter what they did. And here's Ray working on this little instrument, dreaming of recording the sounds from space, starting in the 1960s. Colleagues said, you know, Ray, you're never going to get tenure. And he said, I don't know what tenure was. It didn't matter to me. I don't know what tenure was. But they said, look, your instrument is so crappy that if the sun blew up, you wouldn't be able to record it. And he said, we'd do better looking out the window. And he thought, yeah, actually, they're right. They'd do better looking out the window. Now, he knew this. His instrument sucked. And he didn't have any money. He didn't have any funding. And he wasn't going to get tenure. And fast forward, 50 years and a billion dollars. And Ray builds an instrument four kilometers long. One on, obviously not single-handedly, with a team by hand of about 1,000 people. One on the coast of Louisiana, one in Hanford, Washington. The instrument is called LIGO. And in 2015, after 15 years of hearing nothing, the instrument was first completed in 2015 years of hearing nothing, they advanced the components to a superior machine, a more advanced machine. And on the eve of September 14, 2015, they're about to start their first science run. Ray says to me a couple of days before that, if we don't detect black holes, this thing is a failure. And they decide they're not ready. And they can't begin a science run. So they're interrupting the instruments. And they're interfering with the detections. And in the middle of the night, it's like four in the morning in Louisiana, like two in the morning in Washington state. They decide they're tired to put their instruments down and they go home. And within the span of about an hour, somewhere in the southern sky comes a gravitational wave. It washes over Louisiana. It's perfectly recorded by the instrument. Coasting across the continental US, it rings the instrument in Hanford, Washington. Ray wakes up. He's in his 80s, right? He's been at this thing for 50 years. And he says, what the hell is this? So this is what they recorded. This was the first detection from the LIGO lab. This is a numerical simulation of what happened. It's not something you could possibly see with a telescope. About 1.3 billion years ago, two black holes, each one about 30 times the mass of the sun, orbited each other in the final throws, the end stage of their life together. They could have been orbiting each other for billions of years. And this is the final fraction of a second. This has drastically slowed down so that we could even perceive it. It took about one-fifth of a second. They collided and they formed one bigger black hole. And in those final throws, they were like mallets on a drum, ringing space and time, creating essentially a sound, a recording of themselves. And it raced out into the universe and was recorded in the machines in Louisiana and Washington. And I'm not sure if my sound's going to work, but let's see. This is what it sounded like. No. There it was. Do you want to hear it again? I don't have a back button. Can you back it up? I know it's a little disappointing, let's be honest. Can we play it again? I'm going to skip this part. We're just going to go to the sound. Don't you think it would be like more baritone or something? I don't know. This looks like more. This was the most beautiful sound anyone had ever heard. And this weirdly leads us back to the Earth. So imagine when this was emitted, this ringing in space time. By the way, it was the most powerful event ever detected since the Big Bang itself. More power came out of that collision than the power in all the stars shining in the entire observable universe combined. And yet none of it came out as light. It all came out in this wisp of a sound by the time it gets to us. The detector recorded a ringing in space time of less than one 10,000th the width of a proton over four kilometers. It's an absolutely stunning achievement. And if you imagine when that sound was emitted, when those gravitational waves were emitted, multi-celled organisms were just differentiating on the Earth. By the time it starts to come near our galaxy, anywhere near our galaxy, it gets within the most distant stars Einstein's born. It's on the way, halfway closer, and people like Ray are neck deep in trying to make this experiment real. By the time it enters a solar system, those experimentalists are just putting the tools down and going home. And you think about it as this race, right, to try to capture something like this. And so here we are back at Earth, which really means Brooklyn. Here I am in Brooklyn with Ray. This is two weeks after Ray received the Nobel Prize, shared the Nobel Prize with Kip Thorne and Barry Barish. Two weeks after that, we're in conversation with Ray, celebrating the accomplishment, celebrating the achievement. And here we are talking about the experiment, LIGO, and how it works. And if you don't know Ray, he's still Professor Emeritus here at MIT. He is one of the most candid, fascinating, best storytellers, wonderful people you'll ever meet. And here I am talking with Ray. And he says at this time, you know, when I started as a kid building high-fives of the first sort, I would carry speaker systems from the Brooklyn Paramount that had just had a fire and they had these huge speakers. And I brought them all, lugged them all on the subway back to Manhattan, where I built high-fi units for the immigrants in the city to listen to the Philharmonic through the speaker systems. He said it was extraordinary. It's extraordinary and all I ever wanted to do was to make music easier to hear. And he describes wanting to record music and had an odd trajectory to then be the first to record the sounds from the universe. Now this, as promised, leads us weirdly back to Brooklyn where we're having this conversation in this particular building, which is called Pioneer Works. It is Center for Experimentation and Art and Music and Science. And it started as an old ironworks factory from the 1850s. This is the view of Pioneer Works. You would see if you were coming off the ferry off the East River and walking up to it. It was originally built and reconstructed by Dustin Yellen, the artist and co-founder of the founding artistic director, Gabriel Florence. And they rebuilt it again after Sandy hit. And it's just an extraordinary, stunning place. And we started the sciences here not long ago, only about two and a half, three years ago, we started doing sciences here. Our commitment is that science just is part of culture. Bringing these stories about the universe, bringing Ray to Brooklyn, that is just part of culture. We don't have to package it into anything else. We don't hide it into anything else. We're not doing site art. We're not doing anything like that. We have these conversations directly with Ray. We have conversations about black holes. 1,200 people show up. Here, I'm talking to George Church, who some of you may know, who's brilliant geneticist here at Harvard. And we're talking to Siddhartha Mukherjee, who won the Pulitzer Prize for his book, The Emperor of All Malades. Here's Richard Dawkins, the famous evolutionary biologist talking about the tyranny of socks. Here's our own Leland Melvin. Yes, applause for the hand. Shout out to Leland talking about chasing space. We just have these incredible public events. And I'll tell you the truth. People ask me all the time, how do you account for you getting these crowds of thousands of people? Or we had an eclipse event. We had 4,000 people lining up outside of the block. And we have no idea. We have no idea. We just know that we're doing something we believe in and people seem to want to be part of it. This is our staff naked in our garden. I know they're really cute. I should tell you who each of them is. When they're not naked in our garden, there's other people in our garden. This is during the eclipse event of August, the Great American Eclipse, a total eclipse event of August a couple of years ago. And we had about 150 solar glasses. And we thought, some people will come to our garden during the eclipse event to see the eclipse. This was one where, 9 in the morning, the eclipse didn't actually start to hit in New York until around 1 PM. I get a call from the director, Gabriel Florence, and he's like, Jana, there's people outside. There's people outside. What are we going to do? The line went around a huge city block twice. We had 4,000 people showing up to look through our telescopes just to get their hands on a pair of solar glasses and be part of the eclipse. Then we have projects like this. I say we don't do science and art, we don't. But what we do is allow some tremendous friction. Between different people and different ideas with very strongly directed visions and concepts. And this is the kind of art project that comes out just naturally. This is by artist Andrea Lauer, who's here, who is an MIT Media Lab Director's Fellow as well. And really the reason I'm here today. Andrea was looking at our events in particular one called Scientific Controversies, one series. And she said, I'm going to make you patches. And the patches are these puzzles. So each patch, you have to kind of unlock, right? There's a game to each one of them. Just to name some of them, we have one-way ticket to Mars, string theory. These are all the different events we did. Many worlds, containment. We have a little pill here with a genetic sequence in it for engineering a cure. Can we know the world, dark matter, artificial intelligence? My favorite, the goddamn particle. And that led to other collaborations. Oh, and I'm wearing some of them today. That led to other collaborations, including this one, which I think is really representative of the kind of use of constraints to find something limitless in art and design. This is a project of Andrea's called Under the Same Sky. And this is very much in progress. So it's showing a jumpsuit that she's going to make for me, a flight suit, based around the Eclipse Expedition of 1919 by Sir Arthur Eddington May 29. So we're coming up to the centenary. And you see behind the textile, the fitting garment for the jumpsuit, and then the textile. The textile is very much based in drawings from the 1700s and the Eclipse. And what I love about it is the idea, and again, these are very early in progress videos and showings. But I'm going to have this whole augmented reality so that if you look at me through the screen in my jumpsuit, which features these drawings, ancient drawings from the Eclipse, you will actually be able to see the Eclipse happening. So this shows a little video demo of how that will proceed. You can actually see the clouds part, and you'll see the Eclipse in progress. And this referenced what actually happened in 1919. So in 1919, it's right at the end of World War I. The Europe is in despair. You know, it's an incredibly brutal, vicious war. All countries limped out of World War I. Eddington, who was a pacifist within six months after the end of the war, decides to lead an expedition to Africa to view an eclipse with the purpose of confirming a German's theory. English scientists confirming a German's theory. This is already a crazy idea, a crazy thing to do. Einstein's famous new theory, which has not yet been proven, the general theory of relativity. And the reason he needed an eclipse, here's the idea that if you imagine a star behind the sun, if space-time is curved, the path of the light would be bent around the sun, and it would appear that the star was actually in a different direction. And you would see it, even though it's directly behind the sun. Now, you can't do this experiment with the sun because the sun is blindingly bright. So you need the coincidence of the fact that the Earth subtends exactly the right size in the sky to completely occult the sun, darkening the sun and allowing you to see this thin ray of light of what should be behind it. And in fact, there was the Haiti star cluster, which they measured to look like it was over there when it was really behind the sun, proving that the path of the light was bent, proving Einstein's theory, catapulting Einstein's fame internationally, making him famous in the English-speaking world. And in some sense, more importantly, confirming that science allowed us to be citizens of the same Earth and not citizens of warring nations. So this changed everything, and it was the first confirmed proof of relativity. When they went out to Africa and they started the expedition, they were under cloud cover and rain. And finally, when the clouds broke, they thought they were going to be out of luck when the clouds broke and parted, the eclipse was already underway, and they were able to capture their somewhat shoddy, let's be honest, in retrospect data. When Einstein was asked, what would you have done if they hadn't observed the bending of the path of light? And Einstein said, I would have been sorry for the dear Lord because the theory is correct. And some people think he was making reference to God. God missed an opportunity to do something beautiful, like the general theory of relativity. Some people think he was saying Eddington, Lord Eddington would have been incorrect. Although honestly, I think that's apocryphal, because I don't know if he had been knighted yet. But anyway, we'll look up the history later. And this leads us in some sense back to where we started, which is in kind of homage to the limit of the speed of light conceding that this cannot be transcended, it is an absolute, but instead of interpreting it as something that hampers us or limits creativity to see it instead as an opportunity to find a kind of explosion and revolution in another direction and to have some gratitude for everything that that fundamental limit has actually brought us. Thank you.