I had it. So, I don't have any obligations to teach students. I could have probably done the same thing had I had tenure, also. It's not overturning all of physics. Einstein did that, but nobody had done one over R. And it wasn't like that was necessarily motivated by anything. So, I wrote up a little proposal, and I sent it to Katinka Matson, who is an agent with the Brockman Group, and she said something which I think is true, now that I know the business a lot better, which was, "It's true maybe it's not the perfect book, but people have a vague idea that there has been the perfect book. So, I still didn't quite learn that lesson, that you should be building to some greater thing. We don't understand dark matter and dark energy. We won't go there, but the point is, I was friends with all of them. Michael Nielsen, who is a brilliant guy and a friend of mine, has been trying, not very successfully, but trying to push the idea of open science. Completely blindsided. I was a fan of science fiction, but not like a super fan. They didn't even realize that I did these things, and they probably wouldn't care if they did. But I get plenty of people listening, and that makes me very pleased. But I want to remove a little bit of the negative connotation from that. Bill Press did us a favor of nominally signing a piece of paper that said he would be the faculty member for this course. So, I wonder, in what ways can you confirm that outside assumption, but also in reflecting on the past near year, what has been difficult that you might not have expected from all of this solitary work? I wrote down Lagrangians and actions and models and so forth. In many ways, it was a great book. There were hints of it. It would be bad. My thesis committee was George Field, Bill Press, who I wrote a long review article on the cosmological constant with. At Los Alamos, yes. It costs me money, but it's a goodwill gesture to them, and they appreciate it. We could discover gravitational waves in the microwave background that might be traced back to inflation. We have been very, very bad about letting people know that. So, I do think that my education as a physicist has been useful in my caring about other fields in a way that other choices would not have been. No, no, I kind of like it here. Soon afterward, they hired Andrey Kravtsov, who does these wonderful numerical simulations. He explains the factors that led to his undergraduate education at Villanova, and his graduate work at Harvard, where he specialized in astronomy under the direction of George Field. So, I kind of talked with my friends. Is writing a graduate-level textbook in general relativity, might that have been perceived as a bit of a bold move for an assistant professor? That was my first choice. With that in mind, given your incredibly unique intellectual and career trajectory, I know there's no grand plan. (2016) The Serengeti Rules: The quest to discover how life works and why it matters. From the outside looking in, you're on record saying that your natural environment for working in theoretical physics is a pen and a pad, and your career as a podcaster, your comfort zone in the digital medium, from the outside looking in, I've been thinking, is there somebody who was better positioned than you to weather the past ten months of social distancing, right? It literally did the least it could possibly do to technically qualify as being on the best seller list, but it did. I should be finishing this paper rather than talking to you, on quantum mechanics and energy conservation. The first super string revolution had happened around 1984. [32][33][34] Some of his work has been on violations of fundamental symmetries, the physics of dark energy, modifications of general relativity and the arrow of time. I've brought in money with a good amount of success, but not lighting the sky on fire, or anything like that. His article "Does the Universe Need God?" Perhaps you'll continue to do this even after the vaccine is completed and the pandemic is over. A coalition of graduate students and scholars sent a letter to the university condemning the decision at the time. There's also the argument from inflationary cosmology, which Alan pioneered back in 1980-'81, which predicted that the universe would be flat. Our senior year in high school, there was a calculus class. I wonder what that says about your sensibilities as a scientist, and perhaps, some uncovered territory in the way that technology, and the rise of computational power, really is useful to the most important questions that are facing you looking into the future. But in 2004, I had written that Arrow of Time paper, and that's what really was fascinating to me. And Sidney Coleman, bless his, answered all the questions. That's not by itself bad. He has also worked on the foundations of quantum mechanics, especially the many-worlds interpretation, including a derivation of the Born rule for probabilities. At the end of the interview, Carroll shares that he will move on from Caltech in two years and that he is open to working on new challenges both as a physicist and as a public intellectual. I'm going to bail from the whole enterprise. No one expects that small curvatures of space time, anything interesting should happen at all. There were some hints, and I could even give you another autobiographical anecdote. We've already established that. There's a lot of inertia. So, if, five or ten years from now, the sort of things that excite me do not include cutting edge theoretical physics, then so be it. There's always some institutional resistance. I remember, even before I got there, I got to pick out my office. He was the one who set me up on interviews for postdocs and told me I need to get my hands dirty a little bit, and do this, and do that. But now, I had this goal of explaining away both dark matter and dark energy. Sean Carroll is a Harvard educated cosmologist, a class act and his podcast guests are leaders in their fields. People always ask, did science fiction have anything to do with it? So, most research professors at Caltech are that. You should not let w be less than minus one." One is you do get a halfway evaluation. What I wanted to do was to let them know how maybe they could improve the procedure going forward. When I went to Harvard, there were almost zero string theorists there. So, we wrote one paper with my first graduate student at Chicago -- this is kind of a funny story that illustrates how physics gets done. Whereas, for a faculty hire, it's completely the opposite. It also has as one of its goals promoting a positive relationship between science and religion. Like, okay, this is a lot of money. They brought me down, and I gave a talk, but the talk I could give was just not that interesting compared to what was going on in other areas. They wanted me, and every single time I turned them down. So, they keep things at a certain level. Harvard taught a course, but no one liked it. So, yeah, I can definitely look to people throughout history who have tried to do these things. It doesn't always work. I wrote a blog post that has become somewhat infamous, called How to Get Tenure at a Major Research University. I was surprised when people, years later, told me everyone reads that, because the attitude that I took in that blog post was -- and it reflects things I tell my students -- I was intentionally harsh on the process of getting tenure. We will literally not discover, no matter how much more science we do, new particles in fields that are relevant to the physics underlying what's going on in your body, or this computer, or anything else. And the High-z supernova team, my friends, Bob Kirshner, and Brian, and Adam, and so forth, came to me, and were like, "You know, you're a theorist. It was July 4th. We certainly never worked together. But it doesn't hurt. www.aip.org/history-programs/niels-bohr-library/oral-histories/XXXX, American Association of Physicists in Medicine, AVS: Science & Technology of Materials, Interfaces, and Processing. I learned general relativity from Nick Warner, which later grew into the book that I wrote. One of the things that the Santa Fe Institute tries to do is to be very, very tiny in terms of permanent faculty on-site. My parents got divorced very early, when I was six. I explained it, and one of my fellow postdocs, afterwards, came up to me and said, "That was really impressive." So much knowledge, and helpful, but very intimidating if you're a student. But you're good at math. Let's put it that way. Everyone sort of nods along and puts up with it and waits for the next equation to come on. It was true that as you looked at larger and larger scales in the universe, you saw more and more matter, not just on an absolute scale, but also relative to what you needed to see. Sean attached a figure from an old Scientific American article assertingthat sex is not binary, but a spectrum. But there's an enormous influence put on your view of reality by all of these pre-existing propositions that you think are probably true. It was like, if it's Tuesday, this must be Descartes, kind of thing. So, anyway, with the Higgs, I don't think I could have done that, but he made me an offer I couldn't refuse. They'll hire you as a new faculty member, not knowing exactly what you're going to do, but they're like, alright, let's see. He's the best graduate student I've ever had. Hiring managers will sometimes check to see how long a candidate typically stays with the organizations they have worked for. There's this huge gap in between what we give the popular press, where I have to fight for three equations in my book, and a textbook, which is three equations every paragraph. The idea -- the emails or responses that make me the happiest are when someone says, you know, "I used to love physics, and I was turned off by it by like a bad course in high school, and you have reignited my passion for it." If there's less matter than that, then space has a negative curvature. We wrote a lot of papers together. When I told Ed Guinan, my undergraduate advisor, that I had George Field as an advisor, he said, "Oh, you got lucky." Sean recounts his childhood in suburban Pennsylvania and how he became interested in theoretical physics at the age of . -- super pretentious exposition of how the world holds together in the broadest possible sense. They come in different varieties. And I thought about it, and I said, "Well, there are good reasons to not let w be less than minus one. It was really the blackholes and the quarks that really got me going. Video of Sean Carroll's panel discussion, "Quantum to Cosmos", answering the biggest questions in physics today, This page was last edited on 23 February 2023, at 10:29. So far so good. More the latter couple things, between collaborative and letting me do whatever I wanted on my own. All of them had the same idea, that the amount of matter in the universe acts as a break on the expansion rate of the universe. So, no, it is not a perfect situation, and no I'm not going to be there long-term. More than just valid. A lot of my choices throughout my career have not been conscious. The modern world, academically, broadly, but also science in particular, physics in particular, is very, very specialized. [11], He has appeared on the History Channel's The Universe, Science Channel's Through the Wormhole with Morgan Freeman, Closer to Truth (broadcast on PBS),[12] and Comedy Central's The Colbert Report. I was awarded a Packard fellowship which was this wonderful thing where you get like half a million dollars to spend over five years on whatever you want. In 2012, he organized the workshop "Moving Naturalism Forward", which brought together scientists and philosophers to discuss issues associated with a naturalistic worldview. But, I mean, I have no shortage of papers I want to write in theoretical physics. They succeeded beyond anyone's wildest expectations. And I knew that. It's a necessary thing but the current state of theoretical physicists is guessing. Having been through all of this that we just talked about, I know what it takes them to get a job. There are a lot of biologists who have been fighting in the trenches against creationism for a long time. Very, very important. Sean, thank you so much for joining me today. So, we made a bet. I think, they're businesspeople. Sean Carroll, bless his physicist's soul, decided to respond to a tweet by Colin Wright (asserting the binary nature of sex) by giving his (Carroll's) own take in on the biological nature of sex. I clearly made the worst of the three choices in terms of the cosmology group, the relativity group, the particle theory group, because I thought in my navet that I should do the thing that was the most challenging and least natural to me, because then I would learn the most. My mom worked as a secretary for U.S. Steel. The whole thing was all stapled together, and that was my thesis. To tell me exactly the way in which this extremely successful quantum field theory fails. What can I write down? So, I think that when I was being considered for tenure, people saw that I was already writing books and doing public outreach, and in their minds, that meant that five years later, I wouldn't be writing any more papers. You have to say, what can we see in our telescopes or laboratories that would be surprising? Also in 2014, Carroll partook in a debate held by Intelligence Squared, the title of the debate was "Death is Not Final". But undoubtedly, Sean, a byproduct of all your outreach work is to demonstrate that scientists are people -- that there isn't necessarily an agenda, that mistakes are made, and that all of the stuff for which conspiracies are made of, your work goes a long way in demonstrating that there's nothing to those ideas. That's not all of it. They don't quite seem in direct conflict with experiment. So, the year before my midterm evaluation, I spent almost all my time doing two things. His recent posting on the matter (at . Being with people who are like yourself and hanging out with them. I taught both undergraduate and graduate students. That just didn't happen. To get started, would you please tell me your current titles and institutional affiliations? I think that's true in terms of the content of the interview, because you can see someone, and you can interrupt them. Honestly, here we're talking in the beginning of 2021. Again, in my philosophy of pluralism, there should be both kinds. Well, I do, but not so much in the conventional theoretical physics realm, for a couple reasons. But, you know, my standard is what is it that excites me at the moment? To be perfectly fair, there are plenty of examples of people who have either gotten tenure, or just gotten older, and their research productivity has gone away. How could I modify R so that it acted normal when space time was curved, but when space time became approximately flat, it changed. Also, I think that my science fiction fandom came after my original interest in physics, rather than before. I think that's the right way to put it. That's actually a whole other conversation that could go on for hours about the specifics of the way the media works. Carroll lives in Los Angeles with . So, I was still sort of judging where I could possibly go on the basis of what the tuition numbers were, even though, really, those are completely irrelevant. As a result, I think I wrote either zero or one papers that year. So, I played around writing down theories, and I asked myself, what is the theory for gravity? That's not what I do for a living. Having said that, the slight footnote is you open yourself up, if you are a physicist who talks about other things, to people saying, "Stick to physics." They actually have gotten some great results. But I do think that there's room for optimism that a big re-think, from the ground up, based on taking quantum mechanics seriously and seeing where you go from there, could have important implications for both of these issues. . Sean Carroll is a theoretical physicist at Caltech, specializing in cosmology and quantum mechanics. If you've been so many years past your PhD, or you're so old, either you're hired with tenure, or you're not hired on the faculty. I think that I read papers by very smart people, smarter than me, doing cutting edge work on quantum gravity, and so forth, and I still find that they're a little hamstrung by old fashioned, classical ideas. Do the same thing for a cluster of galaxies. Carroll has also worked on the arrow of time problem. So, many of my best classes when I was a graduate student I took at MIT. I can't quite see the full picture, otherwise I would, again, be famous. Move on with it. Well, as in many theoretical physics theses, I just stapled together all the papers I had written. That was clear, and there weren't that many theorists at Harvard, honestly. Moving on after tenure denial. Knowing what I know now, I would have thought about philosophy, or even theoretical computer science or something like that, but at the time, law seemed like this wonderful combination of logic and human interest, which I thought was fascinating. No one cares what you think about the existence of God. As ever, he argues that we do have free will, but it's a compatibilist form of free will. It was a little bit of whiplash, because as a young postdoc, one of the things you're supposed to do is bring in seminar speakers. I was in on the ground floor, because I had also worked on theoretical models of it. People know who you are. Everyone knows about that. He's supposed to answer the questions." So, the density goes down as the volume goes up, as space expands. It's really the biggest, if not only source of money in a lot of areas I care about. I remember -- who was I talking to? I do firmly believe that. It was on a quarter system: fall, winter, spring quarters. There's no other input that you have. But very few people in my field jump on that bandwagon. We made a bet not on what the value of omega would be, but on whether or not we would know the value of omega twenty years later. I was kind of forced into it by circumstances. When I was at Harvard, Ted Pyne, who I already mentioned as a fellow graduate student, and still a good friend of mine, he and I sort of stuck together as the two theoretical physicists in the astronomy department. But I was like, no I don't want to take a nuclear physics lab. I'm not sure how much time passed. The unions were anathema. I assume this was really a unique opportunity up until this point to really interact with undergraduate students. Every cubic centimeter has the same amount of energy in it. I am a Research Professor of Physics at Caltech, where I have been since 2006. Did you get any question like that? The theorists were just beginning to become a little uncomfortable by this, and one of the measures of that discomfort is that people like Andrei Linde and Neil Turok and others, wrote papers saying even inflation can predict an open universe, a negatively curved universe. The only way to do that is to try, so let's see what happens. Author admin Reading 4 min Views 5 Published by 2022. So, it would look like I was important, but clearly, I wasn't that important compared to the real observers. So, if you've given them any excuse to think that you will do things other than top-flight research by their lights, they're afraid to keep you on. Of course, Harvard astronomy, at the time, was the home of the CFA redshift survey -- Margaret Geller and John Huchra. The astronomy department was great, the physics department was great. It helped really impress upon me the need for departments to be proactive in taking care of their students. George Rybicki was there, and a couple other people. No, quite the opposite. This is a very interesting fact to learn that completely surprised me. That's why I joined the debate and speech team. I think the reason why is because they haven't really been forced to sit down and think about quantum mechanics as quantum mechanics, all for its own sake. It was a lot of fun because there weren't any good books. Sean has a new book out called The Big Picture, where the topic is "On the Origins of Life, Meaning, and the Universe Itself". But interestingly, the kind of philosophy I liked was moral and political philosophy. Planning, not my forte. They are . It's literally that curvature scalar R, that is the thing you put into what we call the Lagrangian to get the equations of motion. Well, the answer is yes, absolutely. Onondaga County. And I didn't. Well, I was in the physics department, so my desk was -- again, to their credit, they let me choose where I wanted to have my desk. Honestly, the thought of me not getting tenure just didn't occur to me, really. Past tenure cases have been filed over such reasons as contractual issues, gender discrimination, race discrimination, fraud, defamation and more. So, I was invited to write one on levels of reality, whatever that means. I guess, the final thing is that the teaching at that time in the physics department at Harvard, not the best in the world. It was just -- could that explain away both the dark matter and the dark energy, by changing gravity when space time was approximately flat? Ed is a cosmologist, and remember, this is the early to mid '90s. This is real physics. But maybe it could. So, you can think of throwing a ball up into the air, and it goes up, but it goes up ever more slowly, because the Earth's gravitational pull is pulling it down. By the time I got to graduate school, I finally caught on that taking classes for a grade was completely irrelevant. That was the first book I wrote that appeared on the New York Times best seller list. So, then, the decision was, well -- so, to answer your question, yes -- well, sorry, I didn't quite technically get tenured offers, if I'm being very, very honest, but it was clear I was going to. To the extent, to go back to our conversation about filling a niche on the faculty, what was that niche that you would be filling? Sean Carroll. We've only noticed them through their gravitational impact. Carroll has a B.S. In some extent, it didn't. But part of the utopia that we don't live in, that I would like to live in, would be people who are trying to make intellectual contributions [should] be judged on the contributions and less on the format in which they were presented. Right. Our Browse Subjects feature is also affected by this migration. A nontrivial fraction of tenure-track faculty are denied tenure, well over the standard 5% threshold for Type I errors that we use in the sciences. Not just that they should be allowed out of principle, but in different historical circumstances, progress has been made from very different approaches. And then I could use that, and I did use it, quite profligately in all the other videos. We don't understand economics or politics. We get pretty heavily intellectual there sometimes, but it warms my heart that so many people care about that stuff. I'd like to start first with your parents. Honestly, I only got that because Jim Hartle was temporarily the director. As long as it's about interesting ideas, I'm happy to talk about it. I also started a new course, general relativity for undergraduates, which had not been taught before, and they loved it. Again, uniformly, I was horrible. Everyone knows -- Milgrom said many years ago in the case of dark matter, but everyone knows in the case of dark energy -- that maybe you can modify gravity to get rid of the need for dark matter or dark energy. That's one of the things that I wanted to do. But anyway, I never really seriously tried to change advisors from having George Field as my advisor. He points out that innovation, no matter how you measure it, whether it's in publications or patents or brilliant ideas, Nobel Prizes, it scales more than linearly with population density. In 2017, Carroll took part in a discussion with B. Alan Wallace, a Buddhist scholar and monk ordained by the Dalai Lama. People were very unclear about what you could learn from the microwave background and what you couldn't. I still don't think we've taken it seriously, the implications of the cosmological constant for fundamental physics. Yeah, and being at Caltech, you have access to some of the very best graduate students that are out there. Otherwise, the obligations are the same. So, I had to go to David Gross, who by then was the director of KITP, and said, "Could you give me another year at Santa Barbara, because I just got stranded here a little bit?" Was the church part of your upbringing at all? Steve Weinberg tells me something very different from Michael Turner, who tells me something very different from Paul Steinhardt, who tells me something very different from Alan Guth. I just want to say. So, he won the Nobel Prize, but I won that little bottle of port. If you actually take a scientific attitude toward the promotion of science, you can study what kinds of things work, and what kinds of approaches are most effective. I still do it sometimes, but mostly it's been professionalized and turned into journalism, or it's just become Twitter or Facebook. Those would really cause re-thinks in a deep way. At Harvard, it's the opposite. As long as they were thinking about something, and writing some equations, and writing papers, and discovering new, cool things about the universe, they were happy. I was thinking of a research project -- here is the thought process. But he does have a very long-lasting interest in magnetic fields. [37] So, as the naive theorist, I said, "Well, it's okay, we'll get there eventually. People had mentioned the accelerating universe in popular books before, but I honestly didn't think they'd done a great job. And it doesn't work well from your approach of being exuberant and wanting to just pursue the fun stuff to work on. If it's more, then it has a positive curvature. So, I said that, and she goes, "Well, propose that as a book. We've done a few thousand, what else are you going to learn from a few million?" Sorry about that. I just drifted away very, very gradually. Often, you can get as good or better sound quality remotely. I thought I knew what I was doing. You really have to make a case. Certain questions are actually kind of exciting, right? Whereas, if you're just a physicalist, you're just successful. Stephen Morrow is his name. I see this over and over again where I'm on a committee to hire someone new, and the physicists want to hire a biophysicist, and all these people apply, and over and over again, the physicists say, "Is it physics?" Do you want to put them all in the same basket? We don't know the theory of everything. In fact, Jeffrey West, who is a former particle physicist who's now at the Santa Fe Institute, has studied this phenomenon quantitatively. Again, because I underestimated this importance of just hanging out with likeminded people. I'm curious if you were thinking long-term about, this being a more soft money position, branching out into those other areas was a safety net, to some degree, to make sure that you would remain financially viable, no matter what happened with this particular position that you were in? The polarization of light from the CMB might be rotated just a little bit as it travels through space. It was very funny, because in astronomy, who's first author matters. Here is the promised follow-up to put my tenure denial ordeal, now more than seven years ago, in some deeper context. We just didn't know how you would measure it at the time. It's the same for a whole bunch of different galaxies. Melville, NY 11747 Maybe it's them. So, let's get off the tenure thing. And he was intrigued by that, and he went back to his editors. He is the Homewood Professor of Natural Philosophy at Johns Hopkins University, teaching in both the . They're like, what is a theory? You don't get that, but there's clearly way more audience in a world as large as ours for people who are willing to work a little bit. [39], His 2016 book The Big Picture: On the Origins of Life, Meaning and the Universe Itself develops the philosophy of poetic naturalism, the term he is credited with coining. Uniquely, in academia the fired professor . This is also the time when the Department of Energy is starting to fully embrace astrophysics, and to a lesser extent, cosmology, at the National Laboratories. Apply for that, we'll hire you for that. The obvious choices were -- the theoretical cosmology effort was mostly split between Fermilab and the astronomy department at Chicago, less so in the physics department. There's a quote that is supposed to be by Niels Bohr, "Making predictions is hard, especially about the future." And number two, I did a lot of organizing of a big international conference, Cosmo '02, that I was the main organizer of. If I had just gone to relativity, they probably would have just kept me. Again, rather than trying to appeal to the largest number of people, and they like it. I think that's a true argument, and I think I can make that argument. For me, it's one big continuum, but not for anybody else. Graduate departments of physics or astronomy or whatever are actually much more similar to each other than undergraduate departments are, because they bring people from all these undergraduate departments. Sean Carroll: I mean, it's a very good point and obviously consciousness is the one place where there's plenty of very, very smart people who decline to go all the way to being pure physicalists for various reasons, various arguments, David Chalmers' hard problem, the zombie argument.