He's supposed to answer the questions." You had already dipped your toe into this kind of work. It was over 50 students in the class at that time. There are so many people at Chicago. Yeah, absolutely. There are a lot of biologists who have been fighting in the trenches against creationism for a long time. We talked about discovering the Higgs boson. Ann Nelson and David Kaplan -- Ann Nelson has sadly passed away since then. It's just wonderful and I love it, but it's not me. There was Cumrun Vafa, one person who was looked upon as a bit of an aberration. Sean, I'm curious if you think podcasting is a medium that's here to stay, or are we in a podcast bubble right now, and you're doing an amazing job riding it? 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. I ended up taking six semesters and getting a minor in philosophy. Forensics, in the sense of speech and debate. So, we had like ten or twelve students in our class. Here is my thought process. Maybe it was that the universe was open, that the omega matter was just .3. I don't want them to use their built in laptop microphone, so I send them a microphone. But other people have various ways of getting to the . There are not a lot of jobs for people like me, who are really pure theorists at National Labs like that. Spread the word. As long as I was at Chicago, I was the group leader of the theory group in the cosmological physics center. So, the density goes down as the volume goes up, as space expands. He said, "As long as I have to do literally nothing. I learned general relativity from Nick Warner, which later grew into the book that I wrote. At Caltech, as much as I love it, I'm on the fourth floor in the particle theory group, and I almost never visit the astronomers. This is really what made Cosmos, for example, very, very special at the time. The whole thing was the shortest thesis defense ever. This transcript may not be quoted, reproduced or redistributed in whole or in part by any means except with the written permission of the American Institute of Physics. Do you see this as all one big enterprise with different media, or are they essentially different activities with different goals in mind? Not to put you on the psychologists couch, but there were no experiences early in life that sparked an interest in you to take this stand as a scientist in your debates on religion. Sean Carroll, a physicist, was denied tenure by his department this year. But the astronomy department, again, there were not faculty members doing early universe cosmology at Harvard, in either physics or astronomy. You have to say, what can we see in our telescopes or laboratories that would be surprising? Recently he started focusing on issues at the foundations of cosmology, statistical mechanics, quantum mechanics and complexity. Well, most people got tenure. I said, the thing that you learn by looking at all these different forms of data are that, that can't be right. First year seminars to sort of explore big ideas in different ways. It's not just a platitude. I said, "I thought about it, but the world has enough cosmology books. Maybe that's not fair. Again, I was wrong over and over again. We wrote a little particle physics model of dark matter that included what is now called dark energy interacting with each other, and so forth. Ted Pyne and I wrote a couple papers, one on the microwave background. But I was like, no I don't want to take a nuclear physics lab. I got the Packard Fellowship. They don't quite seem in direct conflict with experiment. But he didn't know me in high school. I don't want to say anything against them. Honestly, maybe they did, but I did always have a slightly "I'll be fine" attitude. I was a credentialed physicist, but I was also writing a book. Well, it's true. So, I will help out with organizing workshops, choosing who the postdocs are, things like that. I FOUGHT THE LAW: After the faculty at the Chicago-Kent College of Law voted 22 to 1 in favor of granting Molly Lien tenure in March, Ms. Lien gave herself (and her husband) a trip to Florence. I just thought whatever this entails, because I had no idea at the time, this is what I want to do. The world has changed a lot. It's not a matter of credentials, but hopefully being a physicist gives me insight into other areas that I can take seriously those areas in their own rights, learn about them, and move in those directions deliberatively. So, there was the physics department, and the astronomy department, and there was also what's called the Enrico Fermi Institute, which was a research institute, but it was like half of the physics department and half of the astronomy department was in it. So, they're not very helpful hints, but they're hints about something that is wrong with our fundamental way of thinking about things. Sean, another topic I love to historicize, where it was important and where it was trendy, is string theory. It might fail, and I always try to say that very explicitly. Stephen later moved from The Free Press to Dutton, which is part of Penguin, and he is now my editor. Various people on the faculty came to me after I was rejected, and tried to explain to me why, and they all gave me different stories. He is a man of above-average stature. That was the first book I wrote that appeared on the New York Times best seller list. They go every five years, and I'm not going try to renew my contract. So, his response was to basically make me an offer I couldn't refuse in terms of the financial reward that would be accompanying writing this book. I might do that in an academic setting if the opportunity comes along, and I might just go freelance and do that. Sean, when you start to more fully embrace being a public intellectual, appearing on stage, talking about religion, getting more involved in politics, I'd like to ask, there's two assumptions at the basis of this question. So, it's really the ideas that have always driven me, and frankly, the pandemic is an annoyance that it got in the way rather than nudging me in that direction. 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. It's a research institute in Santa Fe that is devoted to the study of complexity in all its forms. I've not really studied that literature carefully, but I've read some of it. I do long podcasts, between an hour and two hours for every episode. How do you land on theoretical physics and cosmology and things like that in the library? Dark energy is a more general idea that it's some energy density in empty space that is almost constant, but maybe can go down a little bit. Sean Carroll is a Homewood Professor of Natural Philosophy at Johns Hopkins who explores how the world works at the deepest level. I'll go there and it'll be like a mini faculty member. The acceleration due to gravity, of the acceleration of the universe, or whatever. Again, I did badly at things that I now know are very obvious things to do. So I'm hoping either I can land a new position (and have a few near-offer opportunities), get the appeal passed and the denial reversed, or ideally find a new position, have the appeal denied, take my institution to court . You took religion classes, and I took religion classes, and I actually enjoyed them immensely. Carroll, while raised as an Episcopalian,[36] is an atheist, or as he calls it, a "poetic naturalist". But exactly because the Standard Model and general relativity are so successful, we have exactly the equation -- they're not just good ideas. 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. She never ever discouraged me from doing it, but she had no way of knowing what it meant to encourage me either -- what college to go to, what to study, or anything like that. That was always holding me back that I didn't know quantum field theory at the time. That's just the system. No one who wants to be in favor of pan-psychism or ghosts or whatever that tells me where exactly the equation needs to be modified. So, I went to a large public school. I don't know what's going to happen to the future of podcasting. I'm also an external professor at the Santa Fe Institute, where I've just been for a couple of years. I love people who are just so passionate about their little specialty. Neta Bahcall, in particular, made a plot that turned over. Whereas, if you're just a physicalist, you're just successful. Let every student carve out a path of study. Carroll was dishonest on two important points. In retrospect, he should have believed both of them. He is, by any reasonable measure, a very serious physicist. We get pretty heavily intellectual there sometimes, but it warms my heart that so many people care about that stuff. The two that were most interesting to me were the University of Chicago, where I eventually ended up going, and University of Washington in Seattle. Believe me, the paperback had a sticker on the front saying New York Times best seller. They actually have gotten some great results. He was a blessing, helping me out. Absolutely. So, as the naive theorist, I said, "Well, it's okay, we'll get there eventually. Or there was. So, the Caltech job with no teaching responsibilities or anything like that, where I'd be surrounded by absolutely top rate people -- because my physics research is always very highly collaborative, mostly with students, but also with faculty members. Rather than telling other people they're stupid, be friendly, be likable, be openminded. But clearly it is interesting since everyone -- yeah. I do a lot of outreach, but if you look closely at what I do, it's all trying to generate new ideas and make arguments. Usually the professor has a year to look for another job. Institute for Theoretical Physics. And that really -- the difference that when you're surprised like that, it causes a rethink. Then, of course, Brian and his team helped measure the value of omega by discovering the accelerating universe. Did you connect with your father later in life? In fact, the short shield solution, the solution that you get in general relativity for spherically symmetric matter distribution, is exactly the same in this new theory as it was in general relativity. That was my first choice. You would have negative energy particles appearing in empty space. And you take external professor at the Santa Fe Institute to an extreme level having never actually visited. Should we let w be less than minus one?" Sean Michael Carroll (born October 5, 1966) is an American theoretical physicist and philosopher who specializes in quantum mechanics, . 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. 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. Could the equation of state parameter be less than minus one? But when I was in Santa Barbara, I was at the epicenter. We're not developing a better smart phone. Because the thing that has not changed about me, what I'm really fired up by, are the fundamental big ideas. Walking the Tenure Tightrope. What was your thought process along those lines? People were very unclear about what you could learn from the microwave background and what you couldn't. Benefits of tenure. It's an expense for me because as an effort to get the sound quality good, I give every guest a free microphone. What were the most interesting topics at that time? 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. I do think my parents were smart cookies, but again, not in any sense intellectual, or anything like that. I love the little books like Quantum Physics for Babies, or Philosophy for Dummies. I think it was like $800 million. Now, of course, he's a very famous guy. The biggest reason that a professor is going to be denied tenure is because of their research productivity. Depending on the qualities they are looking for, tenure may determine if they consider hiring the candidate. And part of it was because no one told me. I presented good reasons why w could not be less than minus one, but how good are they? It doesn't always work. Carroll has a B.S. The discussion with Stuart Bartlett was no exception. So, they looked at me with new respect, then, because I had some insider knowledge because of that. I got to reveal that we had discovered the anisotropies in the microwave background. Why don't people think that way? MIT was a weird place in various ways. So, the fact that it just happened to be there, and the timing worked out perfectly, and Mark knew me and wanted me there and gave me a good sales pitch made it a good sale. The argument I make in the paper is if you are a physicalist, if you exclude by assumption the possibility of non-physical stuff -- that's a separate argument, but first let's be physicalists -- then, we know the laws of physics governing the stuff out of which we are made at the quantum field theory level. Especially if your academic performance has been noteworthy, being denied tenure, in effect, fired by your peers is the ultimate rejection of the person. This morning Wilson responded to a report in the Athletic that said he asked the organization to fire both head coach Pete Carroll and general manager John Schneider last offseason. However, Sean Carroll doesn't only talk about science, he also talks about the philosophy of science. So, I got really, really strong letters of recommendation. Being with people who are like yourself and hanging out with them. You're so boring and so stilted and so stiff." Did you do that self-consciously? 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? So, that would happen. I very intentionally said, "This is too much for anyone to read." The two groups, Saul Perlmutter's team, and Brian Schmidts and Adam Riess's team, discovered the accelerating universe. It's not just trendiness. By and large, this is a made-up position to exploit experienced post-docs by making them stay semi-permanently. Some field needs to care. So, you're asking for specific biases, and I'm not very good at giving you them, but I'm a huge believer that they're out there, and we should all be trying our best to open our eyes to what they could be. It's funny that you mention law school. Are you particularly excited about an area of physics where you might yet make fundamental contributions, or are you, again, going back to graduate school, are you still exuberantly all over the place that maybe one of them will stick, or maybe one of them won't? As far as that was concerned, that ship had sailed. They are . When I wrote my first couple papers, just the idea that I could write a paper was amazing to me, and just happy to be there.