Visualizing Science: From Black Holes to the Future with Peter Galison, Director of the Collection of Historical Scientific Instruments


Jennifer Berglund, Peter Galison

Jennifer Berglund 00:04

Welcome to HMSC Connects!, where we go behind the scenes of four Harvard museums to explore the connections between us, our big, beautiful world, and even what lies beyond. My name is Jennifer Berglund, part of the exhibits team here at the Harvard Museums of Science and Culture, and I'll be your host.

Jennifer Berglund 00:34

Today, I'm speaking with Peter Galison, a filmmaker, professor of physics and the history of science, and director of the Collection of Historical Scientific Instruments at Harvard. Peter's work involves the role images play in science. He was part of the team that successfully imaged a black hole, and he made a film about it called The Edge of All We Know. I wanted to hear his views on the ways in which science, art, and images intersect, and the power they exert on the human imagination when used together. Here he is.

Jennifer Berglund

Peter Galison, welcome to the show.

Peter Galison

Pleasure to be here.

Jennifer Berglund

Much of your work involves what you call the problem of imaging in science. What do you mean by that, and how are you addressing it?

Peter Galison 01:33

For a long time, I've been fascinated with the role that images play in persuading scientists that they're looking at something real, something interesting, under their microscope, through their telescope, in their particle detectors. So a lot of my work has been around that. If epistemology is the study of how we gain and secure knowledge, I'm interested in the way the visual participates in the epistemology of science. So that's cut across many different projects that I've worked on over the years. I wrote a book called Image & Logic, which is about two competing ways that particle physicists have extracted information about the micro world. On the one side, they make pictures, cloud chamber pictures of tracks moving through vapor and leaving droplets behind, or of bubble chambers, where a particle goes through and makes little bubbles inside a medium of liquid hydrogen or other substances. And then there's another tradition that is, in a way, anti-visual. It's arguing by statistics and using counters. And so I was interested in the way these two traditions worked in particle physics and how differently they viewed what it would take to persuade them that there was something real in a particular interaction. And then how these two traditions came together in more recent years to make digitally composed images, but on the basis of electronics. And that's a transformation that's happened in many different areas, in astronomy and medicine. There are two traditions in medicine. Doctors listening to the body and feeling the body, and then looking at aspects of the body with different kinds of instruments. And how these came together, for instance, in MRIs or CAT scans, where you can use electronics to extract an image joining these different traditions. And then I've been interested in film as a way of getting at the materiality of science, and what science is actually like in the circumstances in which it's conducted. What does laboratory work really feel like? How is nuclear waste really stored? What does it feel like to work amidst the burial of nuclear waste? Or in my recent film, The Edge of All We Know, about how we can take a picture of a black hole.

Jennifer Berglund 03:58

You are a part of the team that in 2019 captured the first image of a black hole and it of course captivated the world. There were donut shops serving black hole donuts, etc, etc. What do you think it was that really captivated the public's imagination?

Peter Galison 04:18

In a way, the black hole story takes its modern beginning with Einstein and his general theory of relativity in 1915, and the solution of his equations by his friend, Karl Schwarzschild, who scribbled it on the back of a piece of paper while fighting on the Russian front in World War I. But it's been 100 years. It's the kind of people talk about a 100 year handshake between the beginning of thinking about black holes in this way and actually being able to observe them with the great LIGO experiment which measured gravity waves emitted when two black holes spin around each other and merge, and our taking the picture of the black hole, as you said, in 2019. I think that the reason that people are fascinated by this is a combination of different things. The idea of a black hole is, in a way, terrifying and fascinating, and elusive in a certain way. Here's this surface where if you fell through it, you would not feel anything different at the moment you pass through. But nothing you could do would ever get out. You couldn't shine a flashlight out, you couldn't send a rocket to get out, nothing. And so this idea of a one way membrane that separates the universe into parts outside and inside, I think, brings up images of death. You know, you can pass from life into death, but you can't come back out. And I think that idea of the black holes as a symbol of loss, or inaccessibility, or death, is something that has captured the imagination of people in science fiction and fiction. In everyday speech, when we say, ‘oh, you know, somebody is a black hole’, or ‘that institution is a black hole’. We use it all the time. And if you're alerted to this phenomenon, you know, you'll notice it in people's speech everywhere. And then I think the name itself is evocative, this idea of a black hole. There's something terrifying about this object that emits no light, reflects no light, but is a kind of open maw to things coming in. And the more you learn about them, the more evocative they are. Inside a spinning black hole, there's a region where it seems time goes backwards, that time and space seem to switch their roles inside a black hole. Black holes are the darkest object in the universe, but they also shoot out, from the gas that surrounds them, it whips them into a kind of beam called a jet that becomes the brightest beacons in the universe. They are kind of our lighthouses from the edge of the visible universe. They're the farthest away things we can detect. For all these reasons, and more, they help shape our galaxies, they're astoundingly interesting to mathematicians, to physicists, to astronomers, to philosophers. For all these reasons, I think they're not like any other of the many interesting objects in physics or astronomy. There's something, I hate to say it, captivating about them.

Jennifer Berglund 07:23

Why create an image of a black hole?

Peter Galison 07:29

I think what images do is, they present us with a certain kind of openness. That is to say, we make an image of something, it could come out quite differently than we expected. And that openness to what we might see, gives an added degree of persuasiveness to the existence of black holes, building on many steps along the way towards believing in their reality from the first symbolic, mathematical, theoretical calculations by Einstein and his followers to observations about these regions of enormous energy at the center of galaxies, to the observation of these jets that go a distance of many, many times the size of a galaxy itself. I think that this was somehow, for many people, a clincher among scientists. But more than that, I think for those working on the project of imaging the black hole, it was a first step. And once you could image a black hole, you could begin to ask much more detailed questions that will unfold as we improve this instrument, which is the size of the Earth, these telescopes all over the earth, connected in a kind of Cat's Cradle of linkages. And that we could begin to explore like what happens at space-time just outside the horizon of the black hole? What are the really precise mechanism by which these jets are launched? If we could study many black holes, not just one or two, we could begin to understand the demography of them in a certain sense. How do they form? How do they age? How did they die? Not by studying one. That would be too slow. But by seeing them at different stages. It's analogous to the way we know the life cycle of a star, because we see stars in many different states. Recently made stars, middle age stars, older stars that are beginning to die, stars that have expanded out to be these things called red giant stars that are collapsing and become supernova. So by studying many stars, you can learn about the evolution of stars. And that's, in a sense, one of the things that we can hope from this first image is that this will lead to many other developments in science that will tell us about their formation, and how they work, how they act on the universe. The early stages, I think the dream of actually making a picture was too far in the science fiction future to imagine. We never knew whether it would really work, you know, there were no guarantees here.

Jennifer Berglund 10:03

Which is interesting that you decided to make a film about it not knowing if it would succeed or not.

Peter Galison 10:10

You know, one of the things that documentary film can do, which I really like, is to show things unfolding, where you don't know exactly what's gonna happen. A lot of science films and I, all credit to them, they can be great pedagogically, start with the answer, and then go back and tell how an individual or group or two competing groups or two competing individuals got there. I think that possibility of things going wrong or of changing is part of what film can do that's really exciting.

Jennifer Berglund 10:42

And it's also part of the scientific process, as you were talking about. What about that process of discovery is exciting to you, personally? And how did you want to show that through film?

Peter Galison 10:56

One of the things that appealed to me, and that got me involved with The Black Hole Initiative at Harvard, in the beginning with my colleagues, was that black holes seem to be unlike anything else, and that they pull in from so many different aspects of our understanding of the world. But I think that what particularly interested me and what drew me back into working on the science directly, was the collaborative aspect of it. The Event Horizon Telescope collaboration, which is an international collaboration of people from all over the world, observatories all over the world, and it's expanding in number. In 2019, the time of publication, we had about 214 members from dozens of countries and institute's all over, and observatories at the South Pole, and Arizona, and Spain. Now, there are ones in Greenland, and there's one in Mexico that's played a very important role, a huge array of telescopes in Chile. This is a voluntary association of people from all over the world. Nobody's paid by a central authority. There's no central command center that tells people what to do. There's no director who can order different groups. We do have a director, but it's not a command performance. It's a voluntary association of people who are tremendously excited about the problem, and who find a way to work together. And I've really enjoyed that on the scientific side. And I've enjoyed working with this very far flung group. We have a local group here at the Smithsonian Astrophysical Observatory, Harvard, MIT, Haystack Observatory, this, our little local cluster of folks. And I've become very fond and admiring of them. A lot of younger, early career scientists, as well as more senior people who've worked unbelievably hard over the years to make this work. And with the film, in a way, it's quite parallel. It was a kind of experiment. So early on, I decided to just start filming. I couldn't have written a script for it the way a lot of films have to be made, right? Even documentary films. Because I didn't know the ending. And you know, there were ups and downs. And the film is also about a collaboration with Stephen Hawking and Andy Strominger, whom I mentioned a moment ago, Sasha Haco, a young graduate student, then at Cambridge, England, and Malcolm Perry, a senior mathematical physicist there. And they struggled, and there were times when the project seemed to be crashing and burning, and they weren't, it wasn't going to succeed. And they didn't know how to proceed very well, a time when they had to bring in computers because they couldn't calculate, it got so complicated. And then when it got simpler and they understood it better, they didn't need the computers. And then in the midst of it all, Stephen Hawking tragically died. And you know, that was a real blow. So, in the end, they were able to succeed with the project. But it's, I wanted to film the unfolding of science, the practice of science, the places of science, materiality of science, things that I am interested in in my written work, but I think in film can give it a complimentary understanding.

Jennifer Berglund 14:08

Most people don't understand that there's sort of this inherent drama in science that sort of plays out. It totally resonated with me, you talking about films just sort of delivering a result and being sort of just pedagogical and not really covering the human aspect, the excitement, the let downs, you know, all of that emotion that is part of the scientific process.

Peter Galison 14:33

It's like the difference between reading a summary guide of a novel and a novel, you know, the summary guide can tell you some plot points and character lists, but if a novel works well, it does much more than that. And my hope, with the film was to capture some of that visceral aspect of people working together, working in real circumstances. You know, what does it mean to make something work at 15,000 feet when there's not enough oxygen? And what does it mean to not know whether a cloud is going to pass over the observatory and ruin the whole run? Or what does it mean for a calculation to alternate between zero and infinity and just nonsense, until finally, it begins to yield something plausible? We made a film called Containment about the attempt to contain nuclear waste for the statutory period of 10,000 years. So when you bury nuclear waste, the government says, you need to mark it and secure it from inadvertent intrusion for 10,000 years. So that meant you had to figure out how to communicate with the 10,000 year future, which fascinated me as a problem.

Jennifer Berglund 15:42

How do we communicate with the future?

Peter Galison 15:45

How do you communicate with the future twice as far from us as recorded human history? You know, it's a staggering problem. And I was riveted by the attempt that people were making to do that. So that used animation in a different way, worked with Peter Cooper, wonderful graphic novelist based in New York, who had done a graphic novel of Kafka's work, and I admired his work tremendously. And he helped us think about the, the scenarios of the future, these imaginary 'what ifs' that people have been using for everything from nuclear war planning to the planning for the future of industry and oil and politics. Scenario planning had become part of the discipline of Futurism, which grew up after World War II. They had Futurists involved in trying to figure out how to speak to the far future. All these scenarios were based in something that was happening in the present, but extended, like asymptotically, like, to the stars. And one of them was people were beginning, when they were first trying to bury this nuclear waste in the late 1980s, early 1990s, there were big earth-mover diggers that were making tunnels for subways, cars, trains, and that technology was advancing very quickly then. So one of the scenarios was, what if they had automated diggers that were digging, say, a transcontinental railroad, underground and underground railway for high speed rail, and it dug into the nuclear waste and released this waste? So that would be an example of a scenario and then people said, okay, well, then we better do something about warning approaches from underground. Maybe we need to bury magnets or metal in various ways that would signal to robots or instruments that they were approaching a no-go area. What if a rocket returned from outer space and crashed landed in this area? It was an area where people were thinking of using rockets, in New Mexico. And so they said, well, let's make radar reflectors on the ground that will warn people, this is not a good place to land or crash land. You know, what if people carted away the stones as they did the markers at Fukushima in Japan, in tidal waves in the past before the Fukushima disaster. So each of these scenarios was designed to create a circumstance that should be countered by the marking group. And so the film would go back and forth between these attempts to imagine a dystopian breakthrough into the nuclear waste and a counter that would be what you would do to try to stop it from happening. These are supposed to be like early warnings of future dangers. The order was to make scenarios of intrusion that happened inadvertently. And they violated that order in one case, where they said there was a successful counter to the way of keeping it from being intruded upon. And that was to keep a kind of living museum there about nuclear power, nuclear waste, what had happened here, and that this would be maintained and visited by schoolchildren and adults in kind of an amusement park way, deep into the future. Well, you know, since then, there have been nuclear disasters, and there is a disaster museum that also is supposed to entertain and inform, in Kyiv about the Chernobyl disaster. There, people have begun to think about building a museum and amusement center, in Fukushima, to warn people about what happened there. And so in a way, as far fetched as some of these scenarios can seem, they also can give us indications of a future.

Jennifer Berglund 19:28

How do you hope your work shapes the world's perception of science? And how do you hope that the Collection of Historical Scientific Instruments exhibits do?

Peter Galison 19:37

I find among my scientist colleagues a tremendous interest, actually, in understanding the history and cultural location of their disciplines. And I think that the Collection of Historical Scientific Instruments can help people approach their own work in a contextualized way. I think it enriches and dimensionalizes the experience both for science students, undergraduates, graduates, postdocs, and for practicing scientists to be able to see their enterprise and their daily work in the laboratory as part of an ongoing project that, you know, lasts decades, in some cases, centuries. Yeah, and then there are particular ways that it can contribute. I mean, when we collaborated with John Huth, colleague and physics on navigation, a show on navigation. We brought in people from psychology when we were doing the Rorschach test show. I find a tremendous interest among the colleagues from across the sciences, and increasingly social sciences, in helping them find their own location in this long train of thought and action.

Jennifer Berglund 20:54

Peter Galison, thank you so much for being here. This has been great.

Peter Galison 20:56

It's been a pleasure, Jennie.

Jennifer Berglund 21:03

Today's HMSC Connects! podcast was produced by me, Jennifer Berglund, and the Harvard Museums of Science and Culture, edited by Amanda Fish. Special thanks to the Collection of Historical Scientific Instruments and to Peter Galison for his wisdom and expertise. And thank you so much for listening. If you liked today's podcast, please subscribe on Apple podcasts, Spotify, Pod Bean, or wherever you get your podcasts. See you in a couple of weeks.