I recently had the chance to interview physicist and author Brian Greene as a part of the 2020 Aspen Ideas Festival, presented by the Aspen Institute. Brian and I have been friends for more than 30 years and met when we were Rhodes Scholars together at Oxford in the 1980s. I have loved watching the arc of his career as a scientist, a creator, and a public intellectual. Today, Brian is a professor of physics and mathematics at Columbia University, where he is director of the Center for Theoretical Physics. We talked about his new book, Until the End of Time, his early education and introduction to science, his progression from reluctant reader to bestselling author, and his quest to explore our significance in an astoundingly vast universe.
(This interview has been edited for clarity and length.)
The Aspen Institute
Dan Porterfield: How did you first get interested in science?
Brian Greene: I grew up across the street from the Hayden Planetarium in New York. One day, I was heading back from an after-school trip there and I felt so tiny. We were thinking about stars and galaxies and other worlds and it just made me feel so tiny. I started asking questions that everybody asked but in a really intense way: “Why are we here?” And it struck me that if there was an answer, we would all know it. But since nobody ever told me the answer, it was clear there was no universal answer. So, if instead of answering the question of “why am I here?” I started to ask, “how am I here?”
DP: You had very good science and math education when you were growing up in New York City. Say a word about that.
BG: I went to public schools. If you have great teachers, you don’t have to be at some fancy, private school. My teachers allowed me to go fast at my own pace and when I exhausted that, one of them gave me a letter that said, “go to Columbia University.” So, my sister and I knocked on doors at Columbia and one guy answered and said, “sure, I’ll teach you for free.” I met with him three days a week over the summer and I took off into all of these areas of mathematics that I never would have experienced if it weren’t for this guy, Neil Bellinson, who really opened the world of math to me as a young kid.
DP: You always had so many diverse interests. Culture, the arts, politics, society. Is that how you were in high school or college? Or did it come later?
BG: Definitely later. I was single-minded when I was a kid. It was just math that I cared about. In fact, I hated reading when I was a kid and it spilled over into college. When I opened a physics textbook and there were a lot of words, my heart sank. When I saw equations, I went “yes!” When I graduated college, I went through a period of deep regret. I got technical training in math and physics, yet I had this opportunity to explore a world of ideas and all I did was move forward in one direction that I had been on for twenty years. When I got to Oxford, where we met, that really shifted for me.
DP: One of our conversations involved popularizing science and making it accessible and exciting to more people. We joined a writing group where we shared what we were working on. Say a little bit about that opportunity of seeing yourself as a writer.
BG: That was a great and unexpected gift to learn about that. To be able to write in a way that wasn’t trying to communicate rigorous ideas of science, but something of the human condition, experience, and how we react to things was kind of a turning point in my recognition of what you could do with language.
DP: I remember you being interested in and struck by some of the absurdities of life. We talked about literature and authors like Albert Camus who pointed to that. Is that something that influences your work as a theorist?
BG: Deeply so. Now, I am working on solving Schrödinger’s Equation of Quantum Mechanics so there’s some absurdity, too. When I was young I had an unexpected introduction to Camus, as my father had a copy of The Myth of Sisyphus, which is all about the deep questions of life when you recognize there might not be some overarching purpose. My life’s work has been, on one trajectory, about trying to understand the physical universe as deeply as possible—but on another trajectory, it has been about how, the deeper we go, we realize there is no overarching purpose. And in the sense of Camus, we try to make sense and meaning. In another sense, that is what my new book, Until the End of Time is about.
DP: How did the book—which is an exploration of time, meaning, and physics—come together?
BG: I’ve written a few books attempting to bring cutting-edge science to people. Every time I was writing one of those books, I felt like there was another story to be told, which is, how do these insights not only show how the world works, but how we fit in and feel? As years have passed, I finally feel like I’m now able to do that in telling this story.
DP: One of the critically important things you write about is a “cosmological timeline.” What does that mean?
BG: We all have a sense of the time scales of our lives. What I wanted to get a deep sense of was how that time scale fits into the cosmological unfolding, from the Big Bang to what scientists might call “The End.” When you follow that grand sweep, it gives you a radically different perspective that has an impact on how you think of yourself within life.
DP: What about the meaning part? With that cosmological timeframe and sense of enormity, as well as the idea that time will end, how, then, do you drive meaning?
BG: When you learn that stars, planets, and life disintegrate, and even that consciousness has a finite duration on a cosmological timeline, it can leave you asking, “what is the point of it all?” If your sense of meaning is derived from legacy and looking to the future, it is going to crumble with time. The argument I make in the book is about the familiar “here and now.” While it’s nothing novel, the way I take you there from the cosmological perspective adds a heft and weight to focus you here. I did have dark periods when I tried to better understand the far future and I went through a transformation where I recognized that the focus needs to be here because there, it disintegrates.
DP: Some people having that same experience of wonder as you as a child combined with deep reflection find themselves sensing the presence of a larger, creating “other.” Could all of this come together with some form of design?
BG: They may be right. Behind it all, there could be some intelligence that has set it up and let it unfold. It’s very difficult to prove that perspective is wrong. But I don’t see the evidence for it, and I’m drawn to the evidence, experiment, and observation behind conclusions. The objective world is important to understand, but the subjective—the spiritual, inner experience of conscious self-reflection—is just as important.
DP: How does this help you ground a sense of your personal morality and ethics?
BG: It’s an interesting and deep question. I, for instance, am not a believer in free will. I believe that the arguments we are touching on here establish that every action we take is the product of the physical constituents that make us up. Some people say if you do not have free will, then morality is gone. I think that is wrong. We are responsible for what our particles do. Period. The question is this: should we be punished? If punishment is for retribution, I do not see any role for it. If punishment is for education, you can learn even if you don’t have free will. If punishment is a consequential perspective to shape future behaviors, then I think that is a justifiable way to dole it out.
DP: Do you mean that we should think of punishment as a form of conditioning?
BG: In some sense. At the end of the day, our behaviors are a product of our genetic and physical makeup that is affected by the stimulus that we receive and the responses that we yield across our lives. If I see something in the world and I see the agent being punished for their actions, my particles get rearranged and say “hey, I don’t want that to happen to me!”
DP: You made the choice to write four books and your particles are the only ones on the planet who could write those books. Don’t tell me they were pre-written, and you happened to grab them! How do you account for that?
BG: You are right. The individual has a particulate arrangement that is iconic, and, therefore, your actions reflect your particle arrangement. So, when Beethoven wrote his Symphony No. 9, it was Beethoven’s particles that had the capacity to do that. But did they freely do that? No. Did I freely write my books? No. In a conventional sense—that I can claim that the actions originated fully and totally within me, that I somehow transcended the forces of the world around me and was able to do something that was not a product of those physical particles acting on me—then no, it was not me.
DP: Yet still, if we don’t have unlimited free will, doesn’t that mean we have some free will?
BG: I would say the answer to that is yes. But it is a kind of freedom that you may not find satisfying, which is: I have a greater arrangement of behavioral responses in me than a rock because a rock doesn’t have the internal organization to respond through a rich spectrum of behaviors. I have this rich spectrum of behaviors. I don’t choose them but, again, if there are stimuli from the environment that are slightly different, my responses will be different. One such response is writing a book. A rock doesn’t do that. It’s not freedom from physical law, its freedom from the constrained behavior that governs the inanimate world. If I write a good sentence or solve an equation, I don’t take credit for it in the way that we usually think about it. I say to myself, “hey particles, nice job! I’m really pleased that the forces came together to yield that outcome.” I am not joking. This is how I really think about how we fit in the world.
DP: Well, let me just say this: my particles love your particles. You are an awesome person, an incredible teacher, a creator, and a great friend.
BG: Well, thank you, I feel the same way.
