Into the Impossible With Brian Keating - Brian Keating interviews Sean Carroll about his book Something Deeply Hidden & Many Worlds (#029)

Episode Date: December 20, 2019

   Buy Sean’s books on Amazon Find Sean Carrol online and listen to his Mindscape podcast  Sean Carroll on Joe Rogan Sean M. Carroll is a Research Professor of Physics at CalTech. He is a theorist who thinks about the fundamental laws of nature, especially as they connect to cosmology. His research involves theoretical physics and astrophysics, especially cosmology, field theory, and gravitation. He has worked on questions involving dark matter and dark energy, modified gravity, violations of Lorentz invariance, extra dimensions, topological defects, cosmic microwave background anisotropies, causality violation, black holes, and the cosmological constant problem. Currently, most of his attention is focused on the origin of the universe and the arrow of time, including the roles of inflation, baby universes, and quantum gravity. Quantum mechanics is the most important idea in physics, and physicists themselves readily admit that they don’t understand it. But rather than treating this situation as an urgent call to action, they have traditionally pretended that the problem isn’t there. In Something Deeply Hidden, Sean Carroll argues that this situation is embarrassing and unnecessary, as we do have a very promising way of understanding quantum reality: the Many-Worlds theory, pioneered by Hugh Everett. This book demystifies the paradoxes of quantum mechanics, explains the Many-Worlds approach at a level never previously attempted in a popular work, and argues that an improved understanding of the foundations of quantum mechanics is crucial to making progress on quantum gravity and the emergence of spacetime. Learn more about your ad choices. Visit megaphone.fm/adchoices

The only thing we can be sure of about the future is that it will be absolutely fantastic. Five, four, two. Today, it's a great pleasure to be with you. Thank you so much for coming to meet me. We're at the campus of the beautiful Loyal of Marymount University, located in the Travel District of Los Angeles, not far from LAX, convenient to all major freeways. And it's a great pleasure to interview you.

I've had the pleasure of reading your books for many years. I think you've autographed every copy I've had except for the most recent copy because that I've read an audiobook or listened to an audio book. Do you have an opinion on audiobooks? Do you think you get as much out of an audiobook? Because you've read it.

You've read it. This one you read it. You get things out of an audiobook. You might not get the same things. Interestingly, there's a bunch of people who have written in to say that they get both. You know, they get the audio book. And then they, if it's, because my books tend to involve, you know, complicated things, right?

You know, mind-stretchy things. So then you want to go back to certain parts of the world and get it. So get both. Get both. That's the advice. Get all three. Kindle, hard copy. Yeah, absolutely.

I know a lot of people. A lot of people like to read the triple play. We call that. The LaGrangean at the end, that's a big picture. That was a standout. This one, this latest book, your latest opus. I thought your previous book might be, you know, used up all the words you could possibly use in your vast brain.

But this one, even more, I think deeply, truly does involve new ideas, new theories, new, new kind of modes of thinking about reality in the universe. And although, you know, I remember when you mentioned it on Twitter, you're going to write a new book in the coming years. It was a couple of years ago. And you said, you know, this book's going to be at quantum mechanics and it's going to solve everybody's problems.

I'm sure everybody's going to understand it. And certainly we come away with a much better understanding quantum mechanics. But I think the book is this deeply misleading because it's really about gravity. And I felt that it was a very, very interesting and beautiful turn of events that only sort of partway through the book after the requisite explanation of how quantum mechanics has been interpreted and could be interpreted that you turn to a much more kind of exciting frontier, at least for physicists like myself and my colleagues, of course, is a popular book. But really, is this the book you set out intending to write two years ago when you made that famous momentous tweet?

You know, the book has a very natural structure of the three different parts. The first part is explaining quantum mechanics, the basics of it, and including a little light introduction to many worlds. And then the second part is a deep dive into many worlds, what it means, why it's difficult, what the alternatives are, et cetera. And the third part is, as you said, an exploration of gravity in the emergence of space time, an argument that, one of the things holding us back from quantizing gravity is if you don't understand quantum mechanics very well. And in particular, the thinking about things in the many worlds way helps us quantize gravity. So I actually bounced back and forth when conceptualizing a book and when writing it, should it be just about many worlds or should it be many worlds building up to this particular view of quantum gravity?

And literally, with a very short period of time, actually literally after I had written, the first draft of part three, I said, let's take it out. Let's just stick with just many worlds because it's a nice, compact, complete story just by that. It's a smaller book, more easily digestible, right? And my editor said, you know, that he really liked the idea that we could show it inaction in modern physics and research level stuff. You know, he said, it's nice, but when all of your dates are 1960 or before,

that's not as much fun as when some of the dates mentioned are 2016 and 2017. Right. And, yeah, reference to modern results. But I think, yeah, really coming up with a way to hook the reader's natural curiosity by quantum mechanics, and there have been a plethora of books, no short of books, yes, as you point out, which is unusual because, you know, that's for something that's not well understood, and I'm not going to use the famous line by the man who hold you now hold his desk, Richard Feynman at Caltech.

You have the Feynman desk. Some professors are chaired. Some are desks. But in this case, I think with all these books, and as you said in your famous, I'm sure everyone's going to understand my version of. This is really the first one. I mean, there have been other books, but they tend to kind of have a concomitant description of the multiverse. And you get into it. But specifically with regard to Everettian theory, this is, you know, one of the more, I mean,

of notable ones that goes into the actual meat and potatoes of that theory. As I said before we sat down, I don't like podcasts where, you know, the host interviews, the authors, she says, tell us, you know, what is a reader going to get on your book? Because it means that a host did not read the book. B, he or she is trying to undermine your sales. And, you know, I know that's the cat food budget. Although I want to point out that this is the first time, I think, in human history. In your last book, you quoted Bill and Ten, and that was excellent.

In this book, you found a way actually to save Schrodinger's cat from ultimate annihilation. No cats were harmed in any public space. Hence the PETA endorsement on the back of the book. So I want to get a little bit outside the realm. But let me just, you know, on that note, what you just said, you know, there are many books of one of the candidates, and not every single one of them, but the vast majority have the philosophy that isn't this weird. We'll never understand it.

It's a mystery, right? And whether or not you believe in the world, I wanted to undo that particular thing. That's why I did think that another book on quantum mechanics was something that had a place in the world, because I want to say, number one, it's not ineffectly mysterious. It's just science, right? And number two, here's a possible way to make sense of it. Now, you might not believe my possible way to make sense of it,

but it can be made sense of, and that's the more important message. Yeah. Yeah, I was questioning whether or not, if I were in your position, would I advocate that a young, you know, science, popular science author, write a book about the foundations of quantum mechanics, you know, as a means to, you know, funding profit. I'm not sure I would. And in the book you point out the fact that nobody writes books

about the interpretations of classical mechanics. I mean, you've touched very deeply on interpretations of statistical mechanics in the origin of time. In your previous books, the Origin Higgs boson, the Park Program universe, et cetera. But I think it's unusual because in our classes, we never sit down. We kind of get pulled a fast one if your physics grad student or even an undergraduate. You don't need to know the foundations of Newtontonian mechanics. As you point out, baseball is going to travel.

It's also true that you probably should spend some time on the homily interpretations of quantum mechanics, and foundations of plumbing mechanics, but we never did. We never teach it to our students that way. So I found this useful, you know, for the professionals in the audience, that this is actually a useful tool for even, you know, advanced or, you know, first year graduate students that are curious about quantum information, cubism, things like that, but also to understand what they're doing, because there's a Merman quote that you use often shut up and calculate.

But he was not saying, no, I know he was. He said and calculated, right. That's right. Yeah, that was sort of the interiors. And I actually have the distinction of being told by none other than, 2019 Nobel Prize laureate Jim Hebel's, to shut up and measure when I start asking him too many questions. He did it. He's the ultimate example. Of course. So he laughed at the colloquium and told me to shut up and measure the C&V. And that's what we're trying to do. And I think what's so interesting about this book and the connections that you make within it is this connection between the small things in the universe, the ultimate quantum things. And the largest thing is the universe, which we study. And, you know, to first order, it might be curious.

for the listener to hear why they should be related at all. I mean, why should the very smallest things be related to the very biggest things? That's maybe question, you know, one, part one of the question. And part two is how can, you know, space time itself, the framework in which Newtonian mechanics is played out upon, how can that emerge from quantum mechanics? And I think that's a key philosophical point in making the book. And I think it's, I think it'll be interesting to hear your thoughts on that. How do we get around this notion that this very small things have almost knowing that?

We don't have to influence ants unless you've done in the basement on the biggest parts of the universe. So to what do you attribute this fascinating connection between the ultra-small, maybe plant-scale structure of space time and the grandness of the cosmos that we see today? Yeah, I mean, I would say that quantum mechanics is not a theory of very small. I think that sometimes we say that. I said that. Everyone says that. But a more precise version of that statement is quantum mechanics becomes necessary when you think about the very small. When you think about it very large, when you get a rocket to the moon, you don't need quantum mechanics.

You just do Mutuania Gravione. You need general relativity to get a rocket to the moon. So quantum mechanics is a theory that has a limit, which we call classical. In certain circumstances, under certain conditions, when things obey certain parameters, then classical mechanics is a very, very good approximation. But that's the puzzle. The puzzle isn't why we need quantum mechanics for the very small. puzzles why classical mechanics works at all, because classical mechanics is so different in quantum mechanics in a fundamental way.

And this, I mean, part of the reason I wrote the book is this is what I'm doing research on right now. Like, why is there a classical and then where does it come from? And what you see, what you do look at the literature on this is everyone cheats. Everyone knows the world is classical, so they just find that the classical mechanics in there, but they don't show why it's necessary or how it could have been the other way. They take certain features of the world for granted, like the existence of space, right, like three-dimensional space, up down, left, right, forward, backward. They just put that in, right?

And as you know, as a physicist, when you learn physics and you want to learn, okay, learning quantum mechanics, let's start with a harmonic oscillator, what do you do? They teach you the classical harmonic oscillator, and there's a process called quantizing each time, right? Quantization. And again, nature doesn't do that. Nature doesn't start with some classical world quantization. it. And my strong conviction is that that's why we haven't quantized gravity. Because we stubbornly insist on starting with a classical theory, whether it's general relativity or string theory or anything

else, and quantizing it. And I think that if we just start with a quantum theory, we're real purely quantum theory from the start without us seeing any classical superstructure. We might be able to show how gravity merges from it. But guess what? That's really hard. It's not at all clear, how do they progress doing that? One thing that is seemingly clear, but even there, I'm going to hesitate, is the laws of physics need to be pretty special to get the classical world emerging at all. So why, or do the laws of physics have that property? I really don't know. I would like to know that. In my more speculative moments, I wonder, like, is there, if you had a random, generic, truly unstructured set of laws of physics, could it somehow

break up into different sectors, all of which had classical limits or something like that. But I don't really see how that happens. Yeah, it seems like, you know, this consistent, you know, fools errand, which is, you know, to find gravity and have it be quantized. But to do it the other way around seems profitable. And, of course, you explore that and the third part of the book. And I think that is a unique, you know, not too often do it. To my knowledge, I haven't seen that explored before.

So to propose, you know, new modalities of think, I think, is very commendable. I mean, let's mention for the people who are not experts out there. You know, one of the things we talk about in classical mechanics is position and momentum, position and velocity. Like momentum classically is just the velocity times the max of a particle. And that in Newtonian physics, that's the state of a particle. You need a position, momentum, I can tell you what it's going to do. But clearly they're not on an equal footing, right?

Like the way that we teach it, the way we conceptualize it, the position comes first, and momentum seems to be derived right out of it. But then you go to this. more advanced supercharged version of classical mechanics called Hamiltonian mechanics, and the distinction becomes a little blurrier, right? Like position momentum now seem to be more equal. And in quantum mechanics, in the formalism of quantum mechanics, they're completely equal. You know, there's an operator P for momentum, there's an operator Q for position.

One might ask why those are letters, but okay, they're the letters. And all the equations they appear in may appear in symmetrical. And that really sort of begins to poke at you and say, why is it like that? Why is there a difference in the position of it? So I have a chapter in the book about that. I'm sure there's no other books that have chapters.

No, that's right. For all you aspiring, coining candidates that's popular science. And I think even in my popular books, I want to say something, something. I don't want to just say, here's the stuff we've discovered and presented pedagogically.

That's part of it. But I also want to make an argument that people can potentially disagree. I think also the fact that there's a frontier, This is not a dead subject. It's not for people that lived 100 years ago. I mean, it's been said by people, I think David Gross might have said, well, you know, we need interpretations of, you know,

or maybe he said something like this. Particles need particle physicists the same way that birds need ornithologists, you know. I think funding against it something like that. Yes, that's right. So in this case, I mean, do we need it? I mean, as you said, classical boss on brackets, Lagrangian theory, and then promoting it with quantum commutation relations, That's about all you get in Sakharai,

are the classical text for those of you know, non-entrics out there that we use in first-year graduate student classes. But nowhere in there does it say, well, there's a whole panoply of different ways you could interpret what is fundamental and what is the actual entity under which, you know, reality is to be ascribed. And I wonder, you know, in the many worlds interpretation, which obviously you're an advocate of,

you've been a lot-spoken of, you mentioned many times in the book, how it's not only appealing to physicists, but it's also major ways in popular culture and films and so forth. And, you know, to what do you attribute this sort of very dominant kind of, I have to be honest with you. I'm almost like bias against the ever-ready in many worlds interpretation, the standard code, which every physicist in almost every book you have read and I have read

will say, we know this isn't right. Here's there all the rules. Yeah, that's right. Yeah, I think that, of course, most physicists, If you ask them about their favorite group of patient on mechanics, they would just say they don't care, right? They don't even want to think of it. And I think that's bizarre and weird. I mean, I've had professional physicists tell me, I don't care what actually happens in reality.

All I care is what the measurement outcomes or the observational predictions. I don't think that any 12-year-old gets excited by science by saying, someday I'm going to make some observational predictions. I don't care what happens in reality. I think that you get excited because you're actually careful. about the real world and what happens in it. And somehow we managed to beat that out of our students. So there's this thing called the Copenhagen interpretation,

which traces back probably to Heisenberg on anyone else, and no one ever explicitly says what it is, and it's kind of very fuzzy, but it has this, it follows this idea that what we're supposed to do is just make predictions not ask what's happening underneath the hood. And if you believe in the real world, there's something happening underneath the hood,

with that in. So I don't think we should be satisfied with that. And I think that we should let our students not be satisfied with it. Right. And yeah, we always have this image of the old ones, you know, go into this field once their productive career. Once they're done with serious.

Right, yeah. As you point out, you know, Einstein when he was thinking about spooky action at a distance and EPR paradox was at the right old age of 48, which is my age right now. So I feel you know, I should have a more, you know, kind of respect to my beard and mustache and hairstyle.

I want to talk about, you know, some of the criticisms that the many world theory does have, but before I would do that, because I think that's standard. So you probably haven't asked that one. Maybe I want to know more about you and what excites you, what fascinates you about life. I know that you, you know, are a very cultured man and you're very erudite man. Obviously, your interests are highly parapetetic. They range from theology to deepen the heart. of astrophysics, cosmology, fundamental physics.

But I also know that you're an ordinary person. You are fascinated by many different things. With the one hand, one leg at a time. One leg at a time. I've done it twice with two legs, but then I'll talk with them. I know you're interested in time. I know that you are an avid, have an avid fascination with watches because I once watched you at an auction putting a thousand-dollar bit in a G-shock.

I found that very unusual, but to each is a no. So I know that you're... It was in a different world. I do own it. You guys do I. I own a couple. Because they're not, because you know the structure around.

You have a bunch of little kids around there. But outside physics. What is Sean Carroll up to? What kind of things do you do that make time pass by without your other symbol? Yeah, I mean, you know, I'm lucky enough that there are things that I do that other people might think are work, that I think are fun. Like, I have my own podcast, right,

called Mindscape. And I write books. You know, I, it's interesting when you write books because I know many professional science writers. And that's what they do for living is right. But they write articles for magazines or websites or whatever. And many of them hate writing books. And I hate writing articles. But I love writing books because I'm like, give me 100,000 words to set people straight. And that's really what I want. Right. And, you know, one of the reasons why I started the podcast is because I love reading other people's books, but it's very hard to find the time, right? I had a big stack of books, and I'm like, I'm never going to read these. But if I need to interview the author, then maybe I'll at least give it.

Chris, you're here today, and I said a book. Yeah, exactly. That's why the podcast is very eclected. I'm not like a thrill seeker in terms of, you know, skydiving or rock climbing like many of our friends are. I like eating good food, drinking good wine. just got back from our annual vacation in Las Vegas where we eat in Norriside food and I play poker, right?

Which is another kind of thing that it's not surprising me or businessists playing poker. The basis of the room comes up. That's right, very, very often. But yeah, that's what I like to do. You know, read, write, talk to people think we want, that I like.

What about speaking and kind of the classical speaking, where she's debating, where she's being on podcasts. Some people, you know, shy away from them. They don't like they're more comfortable behind a computer screening or notepad. Where do you fall on that spectrum? Yeah, you know, I was as a kid,

one of these people who thought, you know, debating was really fun. I joined the debate team, called the speech team in high school. And I was terrible. Like, I, in fact, over and over again, I got the same comment that, you know, what you're saying is somewhat interesting,

but your delivery is sucks. It's just that you can't give a talk to save your life. And, you know, I worked at it. And there was like a little phase transition. You know, the moment I can pinpoint my senior year in high school where I sort of became a good public speaker. And I loved being on the debate team because it did help teach you logic and argumentation

and speech and so forth. But I actually don't like debating as such anymore. I mean, I think that... Do you have some notable debates with people like, really... I've done it. I've done it. Beamanely, you know, respectful, but... Yeah, I just want to unliked.

Yeah, I just want to unlikable. Pept for example. And, yeah, I do think that it serves a purpose, but, you know, people on Twitter,

for example, like, debate me. I like to me Twitter is, I love Twitter as a medium, but not for discussions. It's just for fun.

It's just pure. Yeah. But, you know, debating, it's a performative act. You know, I'm happy to debate with someone like

William Lane, Craig, or even Alexander by debate on Life, Life and Death with, but not because we are advancing human knowledge, but because we're sharing some existing human knowledge with the audience, right?

I think that if you actually, you know, there's a different thing you do. If you have two people with the same goals of understanding the world, they don't debate, they say, don't talk, right? They discuss, right? And that's much more like what I do on the podcast, right? Like, even when I have people on the podcast

who I disagree with, my goal is to let them have their saty and maybe, you know, note my reasons for not believing them, but then move on. I'm not there to show why they're wrong or anything like that. That just is too much. And a similar kind of canard leveled against science authors, popular science authors, is that it's not really something a serious scientist does. And, you know, I got some criticism along those lines in my book, which you were kind enough to blur with the phrase readable, which I thought was, you know, a little overselling it. It was readable.

No, I think you were much more effusive in your praise, and I'm very grateful that you were so. But, you know, kind of you get comments that, oh, well, you know, you're spending your time writing boats and I'm in the laboratory during the series. I'm in the throes of the calculation. So how do you react to that? How do you have the day job and the night job? And what do you view as the responsibility or maybe lack of of a professional scientist in terms of communicating?

I think it's not just scientists. I think academics more generally have this weird point of view that says, oh, you are spending your time making what we do for a living accessible and interesting to outsiders, therefore you are trash. You are helping taxpayers fund me, therefore I sustain you. Although they want to verbally say that, but that's sort of, that's the functional end of their criticism. I think that's exactly right.

They won't overtly say. Then what you say, well, what they'll say is we love popularization or outreach or things like that. And then you say, okay, this person who does it, they're like, yeah, they're not that. It's not. They could really, they should really spend their time doing research. So, you know, what can I say? I spend my response to that is to not care. Like, you know, just to do, you know, it has hurt my career in various ways.

It's helped my career in various other ways. So what can I say? It's what I want to do. So as long as they can do it, I'm going to do it, and they can live with it. Right. And it brings you joy, right? Yeah, I think that's not as you. And you also mention about the responsibility aspect.

I mean, I would be not completely honest if I said that I did this out of some sense of duty or obligation. I like it. I do enjoy it. And I enjoy it. Even if no one read it, I like the writing. Like I said, I really do enjoy that sort of puzzle solving of getting the pieces together. And you learn things. You realize you understand things better when you've written.

book about them. I don't think that individual scientists have any responsibility to talk to the general public. I think the field has a responsibility. There's many scientists what I think would be terrible talking to the general public. And that's fine. I should say deeply hidden. That's perfectly fine. But I think that as a field, you know, we rely on the public, and especially the kind of stuff that you and I do, which is not going to cure cancer, right? We're really in it for curiosity, curvy research. I'm understanding how the world works. And if the world of taxpayers and citizenry of the polity comes up with money to pay for you to discover things about reality, and then you don't tell them what you discover.

Like, what is the point of that? Yeah, my late colleague Hans Parr, at least in San Diego, used to tell me, you know, we serve at the pleasure of politicians who currently aren't engaged in any serious war that requires physicists or astronomers to engage their mental capacities. into, right? And that Miller Grass Tizan is written about that, the partnership between alliance, between astronomy and big military industrial campaigns.

I want to talk a little bit just about kind of the places that your mind has taken you, and I think a lot of, as I see you, in the role of a popular science writers, all that's one of your many abilities, but also as a teacher, and I know that your teaching is very important to you

at Caltech and your kind of day job, so to speak, a lot of think you are at night or if you're right during the day or at Feynman's desk. But in terms of that's axis of pleasure and obligation, I mean, where does teaching fall? Is it something that, one thing we're concerned about at the Arthur C. Clark Center for Human Imagination is, can you teach imagination? Can you teach creativity? And as you know, and as I know, and many of our colleagues know, science is eminently creative. I think to think of it as this purely analytic and quantitative aspect of human nature

is not respecting its role as a part of culture. I think science is culture. And yet, you know, some people, there is sort of a distinction between whether creativity, like, you know, brilliance can that be taught? And then where do you fall on that kind of axis? Well, I think, you know, something I've come to appreciate that there was a weird thing that who said to me the very first time I told my own course, which is when I was a postdoc, actually.

One of the professors at MIT, where I was a postdoc, who was scheduled to teach general relativity, went on sabbatical and never came back. So they were stopped without anyone teaching the course. So they asked me as a postdoc to teach general relativity. For better for worse, I said yes. And that ended up turning to lecture notes, which ended up turning to a book.

So it affected me in the world that way. But at the time, I was living, you know, poor postdoc living in someone's house and I was living in the top four of a house owned by this couple of those psychologists and the guy learns that I'm teaching and he was a professor

himself of psychology and he said whatever the subject matter that you're teaching what your students will actually take away from you most importantly is your moral example and I'm like maybe that's true you're teaching psychology I'm teaching general

relativity whether you're take away from me or the symmetry he's the Riemong cancer, right? But years later, I realized he was right. And maybe moral example isn't how a scientist would say it, but I don't know if you can teach brilliance or creativity or imagination. What you can do is show it, right? I don't know how to articulate how to be a good scientist, but I can be an example of a good scientist.

The way that you teach, are you willing to say, I don't know, are you willing to do things in real time? how careful are you about doing different things? How much is it in explaining why things are one way rather than the other way? How much do you care about, how the students are doing, et cetera? All of that is at least probably much more important than the actual subject, rather, which after all, they can get from the book. Yeah, I mean, I've kind of noticed throughout the questions to many different experts,

you know, from Pulitzer Prize winning poets to Nobel Prize winning physicists, that there is sort of a notion that you can, can teach. You can teach certainly well and you can inspire, but potentially creativity has to be something else, something else that's perhaps emergent once they're exposed to these things. You know, it might be like some of my artist friends say, when I made a young person who be an artist, I say go and paint the masters. First do that. First understand where it can, who are the masters in our discipline. Learn the rules and then right. Yeah, that's exactly right. So I think that that is kind of maybe holds true across this aspect of culture.

And that same dear colleague of mine who passed away, unfortunately last year, Hans Bar used to say that general relativity was the crowning accomplishment of Western civilization. I'll just leave that there. I want to add one other thing to what you said a few minutes ago when we're talking about taxpayers and so forth. Science, you know, quantum mechanics, I would say, in astronomy in my case, is something that's apolitical or is sure. should be. I would say, you know, there's no Republican constellation over there, a Democrat comet over, you know, it's just, and yet we see nowadays people waiting into politics, and I think sometimes I think there's a little bit too much of the halo effect. This first Albert Einstein was very smart. He understood the speed of light, so let's ask him about,

you know, what should there be in terms of how many nations should it be on Earth? I know that you have multiple online personalities, not my own thing, not for psychologists, but you have a political Sean Carroll account and do you believe there is an obligation for scientists to be political and if so is there some sort of scientific litmus test

or whatever that you know an authentic scientist should hold or do you believe that you can have you know in front of a full spectrum of. Yeah I mean I think that it's a little bit of an exaggeration to say that science is not the universe. Yeah.

The universe does what it does. It's what a our political beliefs are. But science is a human activity that is embedded in politics and psychology and hopes and dreams and loves and fears just like everything else, right? And admitting that, I think, is important. I think that there's no necessary connection

between one's science and one's politics. I don't think that there's any responsibility on the part of the individual scientists to get involved in politics. I don't think that being a scientist gets you any special expertise points when it comes to politics. But I also don't think that you should shut up about politics just because you're a scientist.

And I think that I completely agree that someone's a famous scientist, they're expounding on politics. There's no reason why the public should spend that much time with seeing them, even if they're Albert Einstein. Likewise, if they're a movie star or a singer is spounding about politics, and yet they do. But I kind of blame the audience for this, right? like let the movie star expound all they want. I'm not going to blame them for expounding, but if CNN wants to report on their, what is the noun form of an expounding?

I don't know. Yeah. Expostulations. Expostulations. And that's just crazy. Why should CNN do that? And you see it quite frequently. Oh, there are so many no-milled-frizz winners that are in favor of this treaty or should vote for that.

But there is, you know, there is, Sometimes there is an overland, right? You climb the change, obviously, a place or arms control might be a place where there's an overlap in scientific expertise and political equities. And again, I think that scientists should be outspoken about politics if that's what they want to do, but they should be judged and how sensible their statements about politics are, not because they have a PhD in atomic physics. Right. That makes right. Any more so, you know, people who ask me to give a talk about cosmology,

and then at the end, it's an ethical sense of climate change. I always say, you know, I hope when you have a talk about climate change, and someone asks them about cosmology, they say, you know, you should consult a real practicing cosmology. Like Ruffold and Bill Foster, who are physicists who shifted into politics. They're very well with that. So there's no incompatibility there, but there's no necessary connection. So we talked a little bit about what you do outside of physics

and outside the lab and writing. I want to get back into the book in just a bit. I do want to talk just, you know, more broadly speaking about your, as we say in the biz, world line. You know, how you got to hear today, maybe not here. The four ways. That's right, which is more complicated

than all of the cosmology and quantum mechanics. But can you explain for the listeners you might not be familiar with your unique path to becoming a atheist, sorry, I should say, a naturalist, as you say. For one example, I'm being a physicist. I don't believe that you weren't originally intending to be a physicist

when you started off in college and Villanamo, if I recall correctly, perhaps I'm wrong, but you had other intentions? No, I definitely wanted to be a physicist. I was one of these lucky kids who decided when they were 10 years ago. They wanted to do. So I was reading books about the big gang of black holes.

My favorite book was a completely unknown book simply entitled High Energy Physics. They talked about all these particles being created with the Bevatron in the 60s. So I was reading this in the late 70s. And I wanted to do that. I had no idea what that meant to do that. And I even quickly figured out,

I wanted to be a theorist. I mean, theoretical physicists. Right? It's a lap. No one wanted me in the lab. Like, I had a chemistry set. I kept to have a lap.

It's surprising that I kept all my clothes and fingers. I got the one. I got the one. I had. But, you know, I was from, I think, the long line of steel workers, I went to public school,

knowing my that made any idea about this involved. So I got a full tuition scholarship to go to Villanova. And so I said, yes, because it was free. So that was nice. And they had a very good, astronomy department, the Kloenosa, it's probably not that great, but good enough that I can just do research.

And, you know, I got published papers out of my undergraduate research and astronomy. But I also got introduced to a lot of interesting topics and politics and philosophy and literature and things like that. So I became a philosophy minor that became very interesting to me. And because a former Villanova alumnus was a research scientist at the Harvard-Smithsonian Center for Astrophysics, I got rejected by the Harvard Astronomy but physics department but the Harvard Astronomy Department took me. So that's why I stayed an astronomer

even though I'm not an astronomer. Like, you know, I'm not an astronomer. People out there are confused by this. Constellations are not there. An astronomer. I've collected data. That's right. Yes. So I was in an astronomy department,

but again, I got lucky enough to be matched with George Field as my advisor. And at the time, I mean, George is a super famous expert in the interstellar medium. galactic physics and things like that. My needle hydrodynamics, again, what I don't do for a living, but he'd become curious about particle physics and cosmology,

and so we wrote papers together and we learned together. And then I got lucky again because people at MIT, Eddie Farie and Alan Pooh found me and asked me to work with them on general relativity and things like that, then hired me as a postdoc. MIT, I went to the Institute of Theoretic Physics in Santa Barbara. Met a lot of brilliant people like the Joe Bolchinsky and so forth. I made, even though, you know, I should have left behind the fact that I came from the long line of steelworkers, like, I never got either never got good advice or never followed.

Probably I got some good advice in there. What kind of getting an example of advice? Well, so just to set the stage for the non-expert. So I graduated with my PhD in 1993. So if you're on the cosmology side of things, that's right after we discovered the CMD. I saw it. It's COVID, right? If you're on the particle physics side of things, or the particle theory side of things,

that was just before we found dualities in supersymmetry and string theory. And gearing up to build the SSC, that's right. But the point is, when I was in grad school, nothing interesting was happening in my field. It was the desert, right? So I was a hot property in the job market just on the basis of promise. Three years later, when I was on the job market again, millions of interesting things were happening, and I wasn't doing any of them. So I was not a hot property in the job market anymore because people really do with CMB or super symmetric d-grains and things like that, string theory.

And no one, you know, like no one explained to me that I couldn't just putter around doing whatever I wanted to do, even though no one else cared about. So I made a huge mistake. Even when I moved to Santa Barbara, my second postdoc, I never wrote any papers with any development in Santa Barbara, which was just dumb. Like from the network connectivity. Just learning and learning new physics, right? I knew my little area of physics, but there's so much expertise and brilliance there. And I was like, I'm doing my thing. Now, the universe saved me because I was like, you know, by that point I was like,

you know, if I want to get a job as a physicist, I need to be the expert in something other people care about, right? But what am I an expert in? You know, not that many things. There was one thing I was an expert that no one cared about, namely the accelerating universe. because they had discovered it yet. But then in 1998, they discovered the accelerated universe. I had written a theory paper on models of dark energy.

I'd written this well-known review article in the Cosmocle constant. I was best friends with people in both groups. Brian Schmidt, Adam Rees, Saul, promoter. I was someone who advised. I was mentioning acknowledgments of the very first paper Saul wrote on Superdating with Ariel Lubar. And I collaborated with Brian Schmidt and Adam recent and the group on the first paper on the Elysian State.

So suddenly, even though I didn't do anything, I was a hot property of the job, I was going to get. The universe changed so that what I did was interesting. I mean, it didn't turn. You were a professor at Chicago, right? No, I got that professor should be because the universe started accelerating. So that was discovered in 1998. I was hired in 1999.

Okay. I was suddenly, the boy away. Yeah. It came that. Finally, they said the, said the acceleration of the universe isn't good for anything. at least in that case, it turned out to do useful work to get you full employment. So I want to turn back a little bit to the book, as I said, I don't want to steal too much thunder from something deeply hidden.

There is. Published September 10th of this past year, and it's a great Christmas present. It's enough for many awards, including Amazon's best science book for the year, and many other awards, words on the back from the most eminent folks in the fields of philosophy, physics, mathematics, astronomy, et cetera. So pick up your copies, plural.

And speaking of contributions to GDP, some people estimate that quantum mechanics contributes 30 to 40% of world GDP, if you consider all things like computers, the Internet. As I said before, as we both kind of maybe hinted that we find it and set it or gross. Does quantum mechanics need us to understand it? And in one place, do the foundations of quantum mechanics, are they important or is it just to kind of establish your bonus fee days you're a true you know physicists used to be called natural

philosophers and you've spoken about this in the past to the extent of that physicists will utter the word philosopher it's in utter disgust and derision so how do we how do we handle that yeah I think that you know you don't need to care right about the foundations of fun it's like if you want to calculate the scattering cross-section of electron positron pairs, or if you want to build a better superconductor, or whatever, you don't need to care about how much anymore. The only reason you need to care is if you care how nature works, if you're curious about. Personally, I am curious about how nature works. Like, when I'm not thinking about quantum mechanics, I'm thinking about what happened

at the Big Bang, which is also not going to build a better smartphone or anything like that, right? But it is, you know, there's a tiny fraction of us that have this enormous privilege that we're paid to think about the deepest mysteries of the universe. And philosophers are among them, right? Like, there's not a bright line in between physics and philosophy. There's a strong overlap, but continuing between them. And I'm going to take however I can get, whether it's from physicists or mathematicians or philosophers or whatever to try to understand me. So another interesting aspect of the book is that you talk a lot about the reality of the ever-ready interpretation of many worlds and splitting the wave function.

So maybe for the non-experts, if you could just delve a little bit into what does it mean to split the wave function? What are many worlds? Even though it is not, I would say it's not the core aspect of the book. And that, I mean, it's an important part of it takes up most of the first two sections. But still, it's not the ultimate conclusion. I think a lot of the conclusion depends on that, obviously. But can you first say a few words about what is in many worlds, what is the many worlds interpretation?

And maybe explain what is an interpretation? Yeah. So it's not an interpretation, by the way. It's been called that. Everyone calls it that. I call it that. It's a theory. What we're dealing with now, like maybe back in 1960s we're debating different interpretations

in one of the comments. But as I say in the book, like it's not debating interpretations of war in peace or doubles. It's a different scientific theories with different variables, different experimental predictions in many cases. And many worlds is one of these theories. And the idea is simply every version of quantum mechanics says an electron can be in a superposition of spin up and spin down, right? And when you measure it, it's either spin up or spin down. But when you're not measuring it, it's both. It really can be a combination of both.

And Everett, if you ever, whoever was a grad student in the 1950s who invented this theory, said, well, look, you are made of electrons and also protons, but you're made of particles which you certainly believe obeyed rules of quantum mechanics. And as we started the podcast with, everything should obey the rules of quantum mechanics, so you should obey the mechanics. So let's not do the Copenhagen thing, which is treat you as classical and imagine that you look at the electron. Let's treat you as quantum mechanics also.

So that's a sort of move that he makes, which if it didn't lead down a certain road, everyone would be happy with, right? And Wheeler did approach that question before Ebert. I mean, he was in the way of function of the universe. Everett's thesis topic was quantized graphic. And then, but he realized, you know,

that no one stands outside the universe to observe it. So I need to do a little bit better. But anyway, he said, look, if you obey the rules of quantum mechanics, then you can be a superposition. So let's ask what the Schrodinger equation, the fundamental dynamical equation, upon mechanics, let's ask what it predicts when you measure this electron. And again, everyone agrees on the answer to that question.

The system, U plus electron, evolves into a superposition of the electron who spin up and you saw it spin up, plus the electron will spin down and you saw it spin up. And Everett's brilliant second move was to say, and that's okay. It's more therapeutic than, you know, physicists. He's like, just believe that. Don't bend over backwards to deny the reality. This is what the equation says. What if that were just true?

And he argues if it were just true, we would interpret that as two separate worlds because what happens in that one part of the weight function and the other part, once they're created, they have nothing to do with the thing. Nothing that happens in one part of the wave function ever affects the other part. So it's as if they are completely different copies of reality.

So the point of many worlds is that he never put in a bunch of worlds. The worlds were always there. All he did was say, let's accept that the worlds are there, ask whether or not people living in those worlds would see the kind of world we see, the kind of events we see. And he says, yes. To be fair, that is an interpretate. I mean, that's sort of an interpretation, right? I mean, saying, let's assume it's okay sort of giving, you know, in Vermont or that it's okay to treat them for the purposes of this exercise, right? For now, we have not actually come up with a, you know, to this point in this particular question.

We have not come out with something specific that was an experimental test of many worlds or something that you would observe differently were many worlds to be accurate description of reality. Well, it's a theory because it's a set of mathematical structures that evolves in a certain level. Now, that's just like classical mechanics, with their relativity or whatever. And of course, you have to point to things in the world and say, this is what is being represented by that mathematical structure. You have to do that in any theory. And Everett has a way of doing that that is more problematic than classical. mechanics where everything is pretty straightforward. So that's fine, and we can argue about that.

But it's eminently falsifiable because all Everett says is there are wave functions and they obey the shrewditor. All you need to show me is a wave function, either a weight function not obeyed the short of your function, or something in the world that is not a wave function. If you do either one of those things, you have falsified many worlds interpretation. But one does apply to Copenhagen interpretation too? Who knows what the Copenhagen interpretation is? I mean, Copenhagen is a certain. I mean, It certainly says that quantum systems do not obey the shorter equation when they find them. Sure. And ever says they always.

Smooth and uniform behavior and that collapse. And that's finally sort of a one. Right. Okay. So for somebody that did want to, you know, as he talked about in the book in a very acute conversation between the daughter, physicist and the father philosopher, maybe a father. She talks to her father and says, you know, imagine you're a billionaire long. billionaire llama.

I'm interested in both because, you know, my experiment right now, the Simons Observatories in Chile. There's no shortage of llamas that we could eventually obtain, and there's a shortage of billionaires. I mean, maybe one of these llamas was willing. So you're a billionaire llama,

and I want to know, how would you go about actually creating a test that you could endow, you know, the Carroll Institute of Technology or the Simons of Touritory? You know, we're taking, we're accepting donations. It's the season. what kind of experiment

could you do? It's unlimited resources. People are doing it. It's not a thought experiment. People are doing this experiment. Get a bunch of atoms together. Get them cool them down. So it's like a boson sign condensators. There are theories in which very explicitly the weight function undergoes spontaneous

without even looking at it. Without the shortening group. So it's an explicit violation of the shortening bureau. And you can calculate that that basically dumps energy into the system. So it will ruin the boz-instein of it. Right. The fact that it's a condensate, right. So it's very rare for any one particle to undergo one of these transitions, but if we had enough particles together, it would eventually happen. So like the rate per particle

something like once for 300 million. So you need a bunch of particles. So it's not an easy experiment to do, but it's a very clear signal that would rule out many worlds. How close would you say we aren't to that type of, and it does, I want to take one other step back. Previously, you and I have spoken about Carl Popper and the things, demarcation, you know, supposition that, you know, Popper suggested that something is not scientific if it cannot be falsified. And you and I have talked about this and his original targets, and you discuss a little bit in the book as well, you know, were things like Marxist dialectic materialism.

And I always point out there's a lot more Marxist dictatorships on Earth today than in Popper's time, so even he's been falsified. But physicists take that as sort of a sacrosanct law of nature. I personally think that that owes to a deep sort of envy, a philosophical envy of the girdles' incompleteness, you know, theorem in mathematics, which says that you can't make sure that a formal system of mathematics is self-consistent. And so to obtain a parallel structure in physics, we kind of rely on this Popper's definition. and it leads people to say some pretty hostile thing,

but the same things about like the multiverse and even many worlds that is not scientific because it cannot be falsified. Now you're talking about a falsification and, you know, due respect to my experimental colleagues who make Bose Einstein comments, it's all over San Diego. You know, my laboratory is not the coldest part of San Diego. It's pretty close, but six mili-keleton currently.

But they can get a lot colder. So why have, when will this occur? I mean, we've had bosaics psychosis for 30 years, and I'll 40 years or more. So what are some of the practical impediments behind this? Is it a matter of time? I mean, are there things that come into the way it function, splitting, the timescales for that.

You mentioned 300 million years. What kinds of things could we do just to accelerate the discovery pace? Yes, let me just mention parenthetically. We already agreed that listening to physicists found about politics, She couldn't give them any more credit than a person on the street. Likewise for philosophers, right? Likewise for physicists expounding about philosophers. Like, physicists love to think that with 15 minutes of thought,

they could solve all the philosophy problems in the world. That's not true. So when you listen to physicists or other scientists talk about the scientific method or what is where it's not science, just, you know, kind of, it's a pretty country. They can go ahead and do that, but they have no expertise whatsoever in that particular question. But, yeah, but even if you take Popper at base value, many worlds is perfectly falsifiable for exactly these reasons.

And Popper said good things about many worlds. And I had to put note, he didn't agree with it. He didn't like it, right? He said it was much better than Copenhagen. He said he was a monstrosse. Yeah, he had his own weird interpretation. He was a non-a-cuitous. Not a good statistic, right?

But, you know, he felt that many worlds was fine. in terms of philosophy, and it is very impulsifiable. Now, this example of getting boson, sign, condensate, and looking for spontaneous collapses is an unusual one just because it's so good. It's like so crystal clear. If you found this, it would be ruled out. There are other alternatives to many worlds, such as bonyin mechanics, which is much harder to see how to rule them out.

In fact, there's plenty of people who believe that they cannot be ruled out. They're experimentally indistinguishable from many world. I'm not so sure about that. I think that this is part of the ramifications of the factories haven't taken the foundations of one mechanic seriously. So we haven't really thought as hard as they can about these questions. It's interesting to see now at colleagues at UC San Diego and Dr. Friedman and David Kaiser and Booth that are working with me and others on so-called cosmic bell tests. And some of these have really ruled out as many loopholes. or the face-based of available loopholes that could plausibly explain using in variables.

So, you know, it does seem there as a resurgence, and they're not the only Chinese groups are very national academy. Very interested in this type of work, quantum information. Maybe we're at the, you know, precipice of a revolution when these types of experiments will be taken, you know, with the seriousness that perhaps they deserve. So I think it is interesting to note that this is something that is potentially falsifiable. It sounds like you're willing to grant falsifiability as having some measure or contributing to a metric of success of a theory. Maybe not the definitive one, as Popper might have argued.

Well, I think it's sufficient but not necessary. If you can say that it's falsifiable, then what's your complaint? Right. You just have to falsify it. You know, one thing I took away from the big picture of your previous book, you know, is sort of this contention that the only that which can interact with the core theory. and is real or can be considered real. So therefore, you know,

poltergeist astrology and maybe even God and things like that, that cannot be, you know, there's no God particle despite the environment terminology for it. So love books with that terminology. That's right. I don't blame it. Yeah, it's got to move your books. But the question of, you know,

whether or not these men in worlds, I mean, is there an interaction with them with the core theory? I mean, can you overlay the superstructure of many worlds itself and ask, does it interact with the core theory? Or can, you might want to explain, what is the core theory,

Franklin checks, definition for what if you would explain that. Yeah, and so, well, just to answer the question, of course, they do interact. I mean, they slipped. They came from the same place, right?

We shared the same past. The world came from the same place. There's a very physical, tangible, interacting between them in the past, just not in the future, right? So the core theory is this way thinking about the laws of physics that govern our everyday lives. And that's a very expansive definition of our everyday lives

to basically include almost every experiment ever done here on Earth, right? So the idea that the world is a bundle of quantum fields, describing electrons and sparks and neutrinos and so forth, interacting through the rules of quantum field theory and the forces of nature of electromagnetism, the strong force, and even gravity at the quantum level is included here. Because as long as you're within a weak field, weak gravitational field, far away from black holes or the Big Bang or whatever, we understand quantum gravity problems. So literally, everything you've ever seen with your eyes, touched your fingers, et cetera, is well-defined, well-described by this core theory.

And people continually misunderstand what I say in. But I don't think you do, but other people do. So I'll say it out loud. Like, they think what I'm saying is that this existence of this core theory either proves that God doesn't exist or prove that life, after death, doesn't exist. exist or prove that collectivity doesn't exist, but none of that is right. What it proves is that if you want to believe in any of these things that somehow affect the world in a way that we show up in your everyday life, then you're saying that this core theory, which I give the equation for in the end of the book, you buy a T-shirt that people

are saying that's wrong. You're saying it has to be modified it somewhat. It's sufficient. So this theory has been tested six ways from Sunday. So if you're going to say it's wrong, fine. tell me how it's wrong, tell me exactly where it goes wrong. Forget about God and all that stuff. If you think that consciousness is something other than a manifestation of physical stuff,

tell me where this equation goes wrong. That's your burden, because we established the equation is pretty good. And could one not say, well, in the future, we didn't know what the weak force, and the core theory of 1929 is very different in the core theory of 1939, et cetera, so are you just thinking of the sort? Could one say, well, we don't know how the sole part, you know, the Solon or whatever, the crouton interacts with the core theory now,

but you're shortchanged against criminalized social teacher. Could one not say that? One cannot say that. That's the thing, because it's a special feature of quantum field. There's different ways of talking about it, but in the book I explain this idea of crossing symmetry, that if something can affect an electron in some way, then you can rotate by 90 degrees,

and you can make that thing by smashing electrons together, right? Fields that talk to each other and have an influence, on each other can be created or destroyed by each other. So if there were things that affected the quantum fields of the core theory, we could make them. They either are just not there or they interact so weakly, they have zero on our everyday life. And no discoveries in future physics will change that unless those discoveries say quantum field theory is entirely wrong.

What about in the other areas? Obviously, a soul is something human-centered, would have to be a low-energy phenomenon. What about those who say, well, we haven't reached high enough in it. You know, when you reach, you know, 10 to 16 TV, you know, looking at the early quantum universe, perhaps. You might see evidence of some part of us. What about the other end? That's not our everyday life.

Yeah, so outside of our everyday life in the very, very early universe, of course, the core theory is nowhere near a position. And in one of your talks, I think it was at Oxford on the philosophy, theology. You have a talk about God is not a good theory, but not God is not a good theory. They just printed the title, actually. Yeah. I'm joking about that.

And in the talk, you talk, yeah, right, that's true. And in that talk, you give a few different arguments. And one of them, which I took issue with, was the notion of, you know, you show the Hubble D.C. And he's like, yeah, what's the point of all these galaxies if there is a creator? So I wonder if you can maybe re-capitulate that argument. But, you know, I can say, well, there's 116 elements on the Piraak table, you know, and maybe God's advocate in this case would say, well, what are the purpose of any of those? You know, why do we need it? We're only made of maybe three dozen different elements in the body.

So aren't you being too enteropocentric? When you talk about what's the purpose of these galaxies out of who knows? I mean, what is, so as an argument against the existence of God is a good theory, not existence of God itself, but why is that sort of a persuasive argument in your opinion? Well, because good theories make good predictions, and we're thinking about this as good basements. So we have different theories of the universe, atheistic models, atheistic models, whatever, and then little subcategories within there.

And then you ask yourself, the whole job of testing theories, is you say, if this theory were true, what should I observe? And then you update. You have a prior probability for all of your theories, and you update that, say, depending on the likelihood, would you have observed that? So if all you knew was that God created the universe and God loves us and God has some special place for us in its heart,

what do you predict should be a large-scale features of the universe? Well, we've done that experiment because there were people thousands of years ago who had this belief, and none of them predicted 200 billion galaxies spread uniformly throughout the world with no human beings on them, right? Completely irrelevant to us. If all you needed was to make humankind, there's much easier ways to do that than create all these universes. So either, let me just finish it.

Either you say, well, I have no idea what God predicts, or you say, well, God wouldn't predict that, therefore, lower the possibility. And if you say, I have no idea what God predicts, you're saying God's not good theory. Right, okay, yeah. So I would say just the same, it might be to paraphrase, but you're saying the existence of the extra 108 elements or whatever on the PR table is further justification in a non, maybe perhaps parsimonious God. But, you know, to use a trivial case, I have, you know, eight colonies in San Diego

who study the Hubble Deep Field who study every one of those galaxies. And, you know, it might be a God's advocate. The purpose of those galaxies, you know, is for human curiosity to understand the universe. Again, I think when you overlay on top of it, the notion that, you know, these attributes of God, that's another thing. but perhaps it's again, just speaking trying to summarize

the excess of these elements and things that we can't interact with or see no purpose for it's not clear to me that that entirely invalidates the notion of even a personal god but certainly taking away the personal aspect to a god entirely a god

of a creator that created the universe perhaps I don't know that that necessarily invalidates it because it's just a I want to say, come on. I mean, of course, you can, after the fact, invent some ex post facto justification. Oh, God would have wanted you do exactly that. And this is the entire history of theology,

discovering new facts about the universe and go, that's just how God would have wanted to do it. And never did they say ahead of time, God will want it to be this way, this fair we're going to have predicted. That's why it's a crappy theory. Okay, good. So I want to conclude the last few minutes

with the plug zone. I want to go and refer people. I will put a bunch of links to that talk that we just mentioned. I want to talk the links to the book. Any other things that are coming up in Sean Carroll's universe that would like the audience? No. I mean,

subscribe to the podcast, but you know, it's the usual thing where after the book comes out, Mindscape podcast, after a book comes out, then it's back to science book. So, like, I'm feeling very chagrins. This is a very low publication. year for me because I got the book out and everything.

I have like three or four publications that are within Epsilon being written. But I want to get these papers done. So, you know, there are many businesses out there. Yeah, by all means, look for papers. I think it was coming out on quantum mechanics, cosmology, and one that I'm really very excited about, about statistical mechanics and causality, why the past and what you cause have causal influence over the future

for not the past, right? remember that you do they can do sort of jay of pearls ideas about causality and things like that so it's something that people have mumbled about i think you can make a bit more than this okay last question dream guest for the podcast alive people who are alive today do i get to like ask you can't violate the core theory show all right people who are alive um you know i've been asked this before and i've never given a satisfactory answer and part of it is i've done pretty well getting my dream guests. And I have a few more coming up

who are pretty good. And I have a long list of people who I have not invited, but if I did invite them, they might say yes. So, you know, I'd love to have Martha Nussbaum on the podcast. I'd let have Barack Obama on the podcast, actually. I have a rule against current politicians or candidates.

Because I think that they have the vested interest in trying to get elected, not telling the truth, right? And Obama probably also has that, even though he's out of office, so he probably wouldn't count either. But I'll have you on his Netflix version. All these people recently passed away. I mean, Nome Chomsky? I mean, Nome Chomsky.

Yeah. David Doidge. I do want to have one of the time. Jennifer is one of the way. She wants to say, you know, she's a woman of the physicist. She wants to stay a lawyer. She must be a liar. We've had her down for a matter of America.

You can, you can, you can. Cokes are in doing it, but he's much happier at home with the cats, write it. All right, that's great. Let me show you the book one more time out there in Hilbert's space. Hilbert Space is real or not? Probably real. Okay. So the universe is real and it's now one of the books.

Get the book. Audio, visual, Kindle, any form possible. Something deeply hidden by Dr. Sean Carroll, physicist at California Institute of Technology. Thank you, Sean. All right, thanks, Brian. The only thing we can be short of about the future. about the future is that it will be absolutely fantastic. Five, four.