So, I used it for my own purposes. Margaret Geller is a brilliant person, so it's not a comment on her, but just how hard it is to extrapolate that. We're not developing a better smart phone. Usually the professor has a year to look for another job. It could be very interdisciplinary in some ways. It worked for them, and they like it. I remember -- who was I talking to? That's why I said, "To first approximation." 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. We don't understand economics or politics. My mom got remarried, so I had a stepfather, but that didn't go very well, as it often doesn't, and then they got re-divorced, and so forth. I know that for many people, this is a big deal, but my attitude was my mom raised me, and I love her very much, and that's all I really need. 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. In other words, you have for a long time been quite happy to throw your hat in the ring with regard to science and religion and things like that, but when the science itself gets this know-nothingness from all kinds of places in society, I wonder if that's had a particular intellectual impact on you. So, I gave a lot of thought to that question. The Santa Fe Institute is this unique place. Did you do that self-consciously? Then why are you wasting my time? The Broncos have since traded for Sean Payton, nearly two years after Wilson's trade list included the Saints. But I think, as difficult as it is, it's an easier problem than adding new stuff that pushes around electors and protons and neutrons in some mysterious way. I wonder, for you, that you might not have had that scholarly baggage, if it was easier for you to just sort of jump right in, and say Zoom is the way to do it. Benefits of tenure. Is your sense that really the situation at Chicago did make it that much more difficult for you? Part of that was a shift of the center of gravity from Europe to America. The topic of debate was "The Existence of God in Light of Contemporary Cosmology". What I wanted to do was to let them know how maybe they could improve the procedure going forward. Sean Carroll: I'm not in a super firm position, cause I don't have tenure at Caltech, so, but I don't care either. Please bear in mind that: 1) This material is a transcript of the spoken word rather than a literary product; 2) An interview must be read with the awareness that different people's memories about an event will often differ, and that memories can change with time for many reasons including subsequent experiences, interactions with others, and one's feelings about an event. If you just plug in what is the acceleration due to gravity, from Newton's inverse square law? In other words, an assistant professor not getting tenure at Stanford, that has nothing to do with him or her. It really wasn't, honestly, until my second postdoc in Santa Barbara, that I finally learned that it's just as important to do these things for reason, for a point. But he was very clear. No, I think I'm much more purposive about choosing what to work on now than I was back then. Talking in front of a group of people, teaching in some sense. Sean, if mathematical and scientific ability has a genetic component to it -- I'm not asserting one way or the other, but if it does, is there anyone in your family that you can look to say this is maybe where you get some of this from? It costs me money, but it's a goodwill gesture to them, and they appreciate it. We can't justify theoretical cosmology on the basis that it's going to cure diseases. It's difficult, yes. He's the best graduate student I've ever had. The production quality was very bad, and the green screen didn't work very well. You can't remember the conversation that sparked them. I think the departments -- the physics department, the English department, whatever -- they serve an obvious purpose in universities, but they also have obvious disadvantages. And guess what? [38] Carroll received an "Emperor Has No Clothes" award at the Freedom From Religion Foundation Annual National Convention in October 2014. Because the thing that has not changed about me, what I'm really fired up by, are the fundamental big ideas. in The Blackwell Companion to Science and Christianity develops the claim that science no longer needs to posit a divine being to explain the existence of the universe. Sean stands at a height of 5 ft 11 in ( Approx 1.8m). 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. That was my talk. I'm not sure how much time passed. So, what they found, first Adam and Brian announced in February 1998, and then Saul's group a few months later, that the universe is accelerating. And that really -- the difference that when you're surprised like that, it causes a rethink. This has been an absolutely awesome four hours. So, an obvious question arises. So, there's three quarters in an academic year. There's very promising interesting work being done by string theorists and other people doing AdS/CFT and wormholes, and tensor networks, and things like that. I was a postdoc at MIT from '93 to '96. 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. So, I wrote a paper, and most of my papers in that area that were good were with Mark Trodden, who at that time, I think, was a professor at Syracuse. You don't understand how many difficulties -- how many systematic errors, statistical errors, all these observational selection biases. Actually, without expecting it, and honestly, between you and me, it won it not because I'm the best writer in the world, but because the Higgs boson is the most exciting particle in the world. But the thing that flicked the switch in my head was listening to music. I've gotten good at it. I thought I knew what I was doing. Something that very hard to get cosmologists even to care about, but the people who care about it are philosophers of physics, and people who do foundations of physics. I became much less successful so far in actually publishing in that area, but I hope -- until the pandemic hit, I was hopeful my Santa Fe connection would help with that. So, the ivy leagues had, at the time -- I don't really know now -- they had a big policy of only giving need based need. -- super pretentious exposition of how the world holds together in the broadest possible sense. Part of it was the Manhattan Project and being caught up in technological development. I'm surprised you've gotten this far into the conversation without me mentioning, I have no degrees in physics. I might do that in an academic setting if the opportunity comes along, and I might just go freelance and do that. It's much easier, especially online, to be snarky and condescending than it is to be openminded. Now, we did a terrible job teaching it because we just asked them to read far too much. In physics, it doesn't matter, it's just alphabetical. At least, I didn't when I was a graduate student. And Sidney was like, "Why are we here? So, I want to do something else. But I loved it. That's my question. He and Jennifer Chen posit that the Big Bang is not a unique occurrence as a result of all of the matter and energy in the universe originating in a singularity at the beginning of time, but rather one of many cosmic inflation events resulting from quantum fluctuations of vacuum energy in a cold de Sitter space. Sean, before we begin developing the life narrative, your career and personal background trajectory, I want to ask a very presentist question. So, Perlmutter, who was the leader of the other group, he and I had talked in very early days, because he was the coauthor with Bill Press on this review article. You get dangerous. All these cool people I couldn't talk to anymore. We are committed to the preservation of physics for future generations, the success of physics students both in the classroom and professionally, and the promotion of a more scientifically literate society. I guess, one way of putting it is, you hear of such a thing as an East Coast physics and a West Coast physics. And he said, "Yes, sure." If you found something like a violation of Lorentz invariants, if you found something of the violation of the Schrdinger equation in quantum mechanics, or the fundamental predictions of entanglement, or anything like that. So, I try to judge what they're good at and tell them what I think the reality is. I went to church, like I said, and I was a believer, such as it was, when I was young. I was a theorist. So, when Brian, Adam, Saul, and their friends announced in 1998 that there was a cosmological constant, everyone was like, oh, yeah, okay. So, becoming a string theorist was absolutely a live possibility in my mind. That would have been a very different conversation if I had. The unhappy result of preferring less candor is the loss we all feel now.". I'd like to start first with your parents. But look, all these examples are examples where there's a theoretical explanation ready to hand. Happy to be breathing the air. They all had succeeded to an enormous extent, because they're all really, really brilliant, and had made great contributions. That's the opposite. So, that was true in high school. I was less good of a fit there. You mean generally across the faculty. So, I could completely convince myself that, in fact -- and this is actually more true now than it maybe was twenty years ago for my own research -- that I benefit intellectually in my research from talking to a lot of different people and doing a lot of different kinds of things. I was an astronomy major, so I didn't have to take them. I've said this before, but I want to live in the world where people work very hard 9 to 5 jobs, go to the pub for a drink, and talk about what their favorite dark matter particle candidate is, or what their favorite interpretation of quantum mechanics is. I would say that implicitly technology has been in the background. We'll see what comes next for you, and of course, we'll see what comes next in theoretical physics. So, I thought that graduate students just trying to learn general relativity -- didn't have a good book to go through. Very, very important. Certainly nothing academic in his background, but then he sort of left the picture, and my mom raised me. Carroll has also worked on the arrow of time problem. Honestly, the thought of me not getting tenure just didn't occur to me, really. It's way easier to be on this side, answering questions rather than asking them. It was very funny, because in astronomy, who's first author matters. Walking the Tenure Tightrope. I think, like I said before, these are ideas that get put into your mind very gradually by many, many little things. Is there something wrong about it?" What the world really needs is a book that says God does not exist. With over 1,900 citations, it helped pioneer the study of f(R) gravity in cosmology. I had an astronomy degree, and I'd hung out with cosmologists, so I knew the buzzwords and everything, but I hadn't read the latest papers. I'm not sure, but it was a story about string theory, and the search for the theory of everything. Sean Michael Carroll (born October 5, 1966) is an American theoretical physicist and philosopher who specializes in quantum mechanics, cosmology, and philosophy of science. I was a fan of science fiction, but not like a super fan. In 2017, Carroll took part in a discussion with B. Alan Wallace, a Buddhist scholar and monk ordained by the Dalai Lama. Okay, with all that clarified, its funny that you should say that, because literally two days ago, I finished writing a paper on exactly this issue. It's an expense for me because as an effort to get the sound quality good, I give every guest a free microphone. Theoretical cosmology at the University of Chicago had never been taught before. And they had atomic physics, which I thought was interesting, and Seattle was beautiful. And I didn't because I thought I wasn't ready yet. It is interesting stuff, but it's not the most interesting stuff. There is the Templeton Foundation, which has been giving out a lot of money. I looked at the list and I said, "Well, honestly, the one thing I would like is for my desk to be made out of wood rather than metal. They had these cheap metal desks. 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. So, I said that, and she goes, "Well, propose that as a book. Intellectual cultures, after all, are just as capable of errors associated with moral and political inertia as administrative cultures are. You nerded out entirely. So, just show that any of our theories are wrong. In my book, The Big Picture, I suggested this metaphor of what I called planets of belief. Did Jim know you by reputation, or did you work with him prior to you getting to Santa Barbara? 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. In particular, the physics department at Harvard had not been converted to the idea that cosmology was interesting. Anyone who's a planetary scientist is immediately interdisciplinary, because you can't be a planetary -- there's no discipline called planetary sciences that is very narrow. I can just do what I want. I started a new seminar series that brought people together in different ways. Good. Not so they could do it. People like Wayne Hu came out of that. So, Katinka wrote back to me and said, "Well, John is right." I was hired to do something, and for better or for worse, I do take what I'm hired to do kind of seriously. 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 there are multiple stories of people with PhDs in physics doing wonderful work in biology. So, you have to be hired as a senior person, as a person with tenure in a regular faculty position. Let's pick people who are doing exciting research. I was like, okay, you don't have to believe the solar neutrino problem, but absolutely have to believe Big Bang nucleosynthesis. And, yeah, it's just incredibly touching that you've made an impact on someone's life. And at my post tenure rejection debrief, with the same director of the Enrico Fermi Institute, he said, "Yeah, you know, we really wanted you to write more papers that were highly impactful." He says that if you have a galaxy, roughly speaking, there's a radius inside of which you don't need dark matter to explain the dynamics of the galaxy, but outside of that radius, you do. It was just -- could that explain away both the dark matter and the dark energy, by changing gravity when space time was approximately flat? This particular job of being a research professor in theoretical physics has ceased to be a good fit for me. So, it made it easy, and I asked both Alan and Eddie. So, between the two of us, and we got a couple of cats a couple years ago, the depredations that we've had to face due to the pandemic are much less onerous for us than they are for most people. As it turned out, CERN surprised us by discovering the Higgs boson early. The idea of visiting the mathematicians is just implausible. But we don't know yet, and it's absolutely worth trying. I took the early universe [class] from Alan. So, I said, well, how do you do that? But, okay, not everyone is going to read your book. That's all they want to do, and they get so deep into it that no one else can follow them, and they do their best to explain. That's less true if what you're doing is trying to derive a new model for dark matter or for inflation, but when what you're trying to do is more foundational work, trying to understand the emergence of spacetime, or the dynamics of complex systems, or things like that, then there are absolutely ways in which this broader focus has helped me. In 2004, he and Shadi Bartsch taught an undergraduate course at the University of Chicago on the history of atheism. I'm curious, is there a straight line between being a ten year old and making a beeline to the physics and astronomy department? Be prolific and reliable. So, there were all these PhD astronomers all over the place at Harvard in the astronomy department. Carroll was dishonest on two important points. There was Cumrun Vafa, who had been recently hired as a young assistant professor. Carroll, S.B. Honestly, Caltech, despite being intellectually as good as Harvard or Princeton, if you get hired as an assistant professor, you almost certainly get tenure. I wanted to live in a big metropolitan area where I could meet all sorts of people and do all sorts of different things. The point I try to make to them is the following -- and usually they're like, sure, I'm not religious. You know, students are very different. So, it's not a disproof of that point of view, but it's an illustration of exactly how hard it is, what an incredible burden it is. Since I've been ten years old, how about that? So, I was done in 20 minutes. I think I talked on the phone with him when he offered me the job, but before then, I don't think I had met him. I just don't want to do that anymore. He has written extensively on models of dark energy and its interactions with ordinary matter and dark matter, as well as modifications of general relativity in cosmology. I think it was like $800 million. [29], Carroll is married to Jennifer Ouellette, a science writer and the former director of the Science & Entertainment Exchange.[30]. Not to give away the spoiler alert, but I eventually got denied tenure at Chicago, and I think that played a lot into the decision. Well, the answer is yes, absolutely. So, it's one thing if you're Hubble in the 1920s, you can find the universe is expanding. Absolutely the same person.". Again, I could generate the initiative to do that, but it's not natural, whereas in Chicago, it kind of did all blend into each other in a nice way. Did you connect with your father later in life? They met every six months while you were a graduate student, after you had passed your second-year exam. There's a few, but it's a small number. If I had just gone to relativity, they probably would have just kept me. So, Villanova was basically chosen for me purely on economic reasons. And probably, there was a first -- I mean, certainly, by logical considerations, there was a first science book that I got, a first physics book. Harold Bloom is a literary critic and other things. So, that was my first glimpse at purposive, long term strategizing within theoretical physics. Probably his most important work was on the interstellar and intergalactic medium. People didn't take him seriously. The tuition was right. I think that's a true argument, and I think I can make that argument. I do long podcasts, between an hour and two hours for every episode. And things are much worse now, by the way, so enormously, again, I can't complain compared to what things are like now. Being denied tenure is a life-twisting thing, and there's no one best strategy for dealing with it. I just think they're wrong. It came as a complete surprise, I hadn't anticipated any problems at all. This didn't shut up the theorists. This was a clear slap at her race, gender, prominence and mostly her unwillingness to bow to critics. Also, of course, it's a perfectly legitimate criterion to say, let's pick smart people who will do something interesting even if we don't know what it is. It denied her something she earned through hard work and years of practice. Well, that's not an experimental discovery. But I'd be very open minded about the actual format changing by a lot. I wouldn't say we're there yet, but I do think it's possible, and it's a goal worth driving for. Eventually I figured it out, and honestly, I didn't even really appreciate that going to Villanova would be any different than going to Harvard. Martin White. And then, even within physics, do you see cosmology as the foundational physics to talk about the rest of physics, and all the rest of science in society? (2016) The Serengeti Rules: The quest to discover how life works and why it matters. At the time, . I do firmly believe that. Those are all very important things and I'm not going to write them myself. Fred Adams, Katie Freese, Larry Widrow, Terry Walker, a bunch of people who were really very helpful to me in learning things. Carroll received his PhD in astronomy in 1993 from Harvard University, where his advisor was George B. We want to pick the most talented people who will find the most interesting things to work on whether or not that's what they're doing right now. The answers are: you can make the universe accelerate with such a theory. People had mentioned the accelerating universe in popular books before, but I honestly didn't think they'd done a great job. I'm curious, in your relatively newer career as an interviewer -- for me, I'm a historian. Can I come talk to you for an hour in your lab?" I think people like me should have an easier time. Again, purely intellectual fit criteria, I chose badly because I didn't know any better. Every cubic centimeter has the same amount of energy in it. So, it's incredibly liberating because I don't have to keep up with the billion other papers that people are writing in the hot topics. However, Sean Carroll doesn't only talk about science, he also talks about the philosophy of science. George Gamow, in theoretical physics, is a great example of someone who was very interdisciplinary and did work in biology as well as theoretical physics. I'm not going to really worry about it. So, the Quantum Field Theory on Which the Everyday World Supervenes means you and I and the tables and chairs around us, the lights behind you, the computers we're talking on, supervene on a particular theory of the world at one level, at the quantum field theory level. As long as it's about interesting ideas, I'm happy to talk about it. So, biologists think that I'm the boss, because in biology, the lab leader goes last in the author list. In fact, I did have this idea that experiencing new things and getting away was important. Then, I went to college at Villanova University, in a different suburb of Philadelphia, which is a Catholic school. It was on a quarter system: fall, winter, spring quarters. What can I write down? Like, you can be an economist talking about history or politics, or whatever, in a way that physicists just are not listened to in the same way. In fact, Jeffrey West, who is a former particle physicist who's now at the Santa Fe Institute, has studied this phenomenon quantitatively. We make it so hard, and I think that's exactly counterproductive. I'm very, very close to phoning up my publisher and saying, "Can we delay it?" So, I think it can't be overemphasized the extent to which the hard detailed work of theoretical physics is done with pencil and paper, and equations, and pictures, little drawings and so forth, but the ideas come from hanging out with people. (The same years I was battling, several very capable people I had known in grad school at Berkeley were also denied tenure, possibly caught in the cutbacks at the time, possibly victims of a wave . In other words, let's say you went to law school, and you would now have a podcast in an alternate [universe] or a multiverse, on innovation, or something like that. I enjoy in the moment, and then I've got to go to sleep afterwards, or at least be left alone. I wonder if that was a quasi-alternative career that you may have considered at some point, particularly because you were so well-acquainted with what Saul Perlmutter was doing. So, I intentionally tried to drive home the fact that universities, as I put it, hired on promise and fired on fear. I'm not making this up. It was a very casual procedure. From neuroscientists and engineers to authors and television producers, Sean and his guests talk about the biggest ideas in science, philosophy, culture and much more. This is real physics. We just knew we couldn't afford it. As I look from a galaxy to a cluster to large-scale structure, it goes up, and it goes up to .3, and it kind of stays at .3, even as I look at larger and larger things. Here is the promised follow-up to put my tenure denial ordeal, now more than seven years ago, in some deeper context. We didn't know, so that paper got a lot of citations later on. Not especially, no. Yeah, there's no question the Higgs is not in the same tier as the accelerated universe. So, there is definitely a sort of comparative advantage calculation that goes on here. I'm going to bail from the whole enterprise. We teach them all these wonderful techniques and we never quite let them apply those techniques they learn to these big interdisciplinary ideas. So, that's one of the things you walk into as a person who tries to be interdisciplinary. Where are the equations I can solve? The bottleneck is hiring you as an assistant professor. But to the extent that you've had this exposure, Harvard and then MIT, and then you were at Santa Barbara, one question with Chicago, and sort of more generally as you're developing your experience in academic physics, when you got to Chicago, was there a particular approach to physics and astronomy that you did not get at either of the previous institutions? It is fairly non-controversial, within physics departments anyway, and I think other science departments, with very noticeable exceptions. Again, stuff that has not been that useful to me, but I just loved it so much, as well as philosophy and literature classes at Harvard. Not to mention, gravitational waves, and things like that. It's not good time management, but we did it and we enjoyed it. The space of possibilities is the biggest space that we human beings can contemplate. So, they have no trouble keeping up with me, and I do feel bad about that sometimes. So, George was randomly assigned to me. If it's more, then it has a positive curvature. To be denied tenure for reasons that were fabricated or based on misunderstandings I cleared up prior to tenure discussion. Carroll recounts his childhood in suburban Pennsylvania and how he became interested in theoretical physics as a ten-year-old.