Into the Impossible With Brian Keating - Paul Davies: What's Eating The Universe? ​(#207)

Episode Date: January 18, 2022

Paul Davies is an internationally acclaimed physicist, cosmologist, and astrobiologist at Arizona State University, where he runs the pioneering Beyond Center for Fundamental Concepts in Science. He also chairs the Search for Extraterrestrial Intelligence Post-Detection Task group, so that if SETI succeeds in finding intelligent life, he will be among the first to know. The asteroid 1992OG was officially renamed Pauldavies in his honor. In addition to his many scientific awards, Davies is the recipient of the 1995 Templeton Prize--the world's largest annual prize--for his work on science and religion. He is the author of more than twenty books, including The Mind of God, About Time, How to Build a Time Machine, and The Goldilocks Enigma. He lives in Tempe, Arizona. Buy What's Eating The Universe - https://amzn.to/3nyERyB Please join my mailing list; just click here http://briankeating.com/mailing_list.php00:00:00 Intro 00:20:36 How do you know when to pursue a scientific hint with further research? 00:33:40 What's unique about your approach to science? 00:38:26 The laws of nature are not perfectly symmetrical. Why tro to find a unifying theory? 00:46:15 What is the Bunch-Davies Vacuum State? 00:52:14 Why did Stephen Hawking make implausible bets? 00:57:50 On black holes and singularities. 01:00:52 Lorentz Invariance and measuring the expansion of the universe with Hawking Radiation. 01:10:19 What are your thoughts on life as information? 01:16:00 Do you believe in God or is that even a meaningful question? 01:25:00 Have your feelings changed on the multiverse and un-falsifiable conjectures in general? 01:41:11 What advice would you give your younger self about how to venture into the impossible? 01:31:53 What advice would you leave in your ethical will? 01:38:20 What would you put on your billion-year time capsule/monolith for the ages? 📺 Watch my most popular videos:📺 A New Contender is Here! https://www.youtube.com/watch?v=-6A6myur--c Frank Wilczek https://youtu.be/3z8RqKMQHe0?sub_confirmation=1 Weinstein and Wolfram https://www.youtube.com/watch?v=OI0AZ4Y4Ip4?sub_confirmation=1 Sheldon Glashow: https://youtu.be/a0_iaWgxQtA?sub_confirmation=1 Neil deGrasse Tyson https://youtu.be/1kxgK6J4S5Y Michio Kaku: https://youtu.be/3to9ymn-XKI Michael Saylor: https://youtu.be/CaN_CDKqXOg?sub_confirmation=1 Sir Roger Penrose: https://youtu.be/AMuqyAvX7Wo Jill Tarter https://youtu.be/O9K9OBd3vHk?sub_confirmation=1 Sara Seager Venus LIfe: https://youtu.be/QPsEDoOTU6k?sub_confirmation=1 Noam Chomsky: https://youtu.be/Iaz6JIxDh6Y?sub_confirmation=1 Sabine Hossenfelder: https://youtu.be/sh98cwRkzAA Sarah Rugheimer: https://youtu.be/w5DxU-lPYK4 Stephen Wolfram: https://youtu.be/nSAemRxzmXM Avi Loeb: https://youtu.be/N9lUceHsLRw Jim Simons: https://youtu.be/6fr8XOtbPqM Be my friend: 🏄‍♂️ Twitter: https://twitter.com/DrBrianKeating 🔔 Subscribe https://www.youtube.com/DrBrianKeating?sub_confirmation=1 📝 Join my mailing list; just click here http://briankeating.com/mailing_list.php ✍️ Detailed Blog posts here: https://briankeating.com/blog.php 🎙️ Listen on audio-only platforms: https://briankeating.com/podcast.php A production of http://imagination.ucsd.edu/ Support the podcast: https://www.patreon.com/drbriankeating Please contact [e-mail] to learn more about sponsoring Into the Impossible. Learn more about your ad choices. Visit megaphone.fm/adchoices

Ask questions like what happened before the Big Bang, what is the nature of time, and then you go to quantum physics, what's the nature of reality, and then you go to life, what is life, and then what is consciousness, you know, all those things, which I love to think about. You can't think about those without coming up against those same age-old questions of centuries were part of religion. Any sufficiently advanced technology is indistinguishable from magic. Open the pod bay doors, hell.

I am thrilled to welcome to the Into the Impossible podcast, a legendary cosmologist, a physicist, an author, an intellectual, and a scholar who was my last guest live in person before the pandemic set in in January 2020. He was gracious enough to come to UCSD and did an event with one of the Benford boys. I always mix up if is Greg or if it's James, but no mind. we talked about whether or not E.T. is lurking in our cosmic backyard. And we had a great discussion about one of Paul's great books from at that time. It was a 10-year-old book, I believe, and that was about the eerie silence. And today, he's back with a new book. And it is called, what is eating? Not Keating. What is eating the universe? And I want to understand, as we often want to be told not to do, Paul, the advice is often saying, don't judge a book by its cover, but I want to judge

this book by its cover. How did you come up with the title and the cover design, which is actually quasi three-dimensional? I mean, it actually opens up. It's quite beautiful. So tell us, Paul, what is the origin of this very provocative and whimsical title? Well, Brian, let me first say that I'm just the author, so I had no choice over the cover. I thought it was quite a clever idea to cut the holes in the jacket to sort of expose the universe behind. So I like it. But as far as the title is concerned, what's eating the universe? So this book, I should say, was my lockdown creation. I'd intended to write the book anyway, but the lockdown accelerated it. Wasn't it wonderful? We were all confined to quarters with nothing much else to do and all the foreign travel cancelled.

And so I thought, well, I'll just bash on and finish this book. So it's come out six months ahead of what it was supposed to. And it started out really as a collection of chapters, each of which deals with some aspect of cosmology. And let me just preface that by saying that I've lived through what I call the golden age of cosmology. I've had a front row seat during that time. I think cosmology moved from when I was a student to being a speculative backwater of science to really a mainstream precision sounds.

We can measure so many things. But like all golden ages, brought its successes, but also opened up lots of new questions and mysteries. And I wanted this to be both a celebration of the amazing achievements that have occurred during my career, but also to show that for any young people thinking of going into science and fascinated by the, The universe, there's still plenty of things left to do, and it's not impossible that some of these anomalies, the things that don't quite fit, will fundamentally transform our understanding of the large-scale structure of the universe. And what's eating the universe is one of the chapters.

We decided, the publisher and I, decided that it was probably a good title to give to the book, but it's just one of a number of mysteries that are being. discussed and it really has to do with, to be quite specific, a funny patch in the southern hemisphere, a cold patch in the sky, that the entire universe is bathed in heat radiation, the fading afterglow of the Big Bang, and the extraordinary thing about this fading afterglow is that it shows us, it's like a snapshot of the universe in its very early stages and it shows us that the universe was almost totally pristine.

I was sort of flawless, perfect baby. But with one or two scars or blemishes, and one of these blemishes is this patch in the southern hemisphere, which is cooler than the rest, cooler than it's supposed to be. And one particular cosmologist, Laura Messini Houghton, had speculated that it's almost as if a cosmic giant has taken a bite out of the universe, speculated it might be because another universe has bumped into hours and has left a scar, or it might even be swallowing hours, or there are other ways in which the universe can be swallowed.

So that seemed like, you know, a really fun topic to give to the title of the book, and so that's really where it came from. And it is a delightfully whimsical book. It's really a collection of essays in a certain sense that I found quite bewitching and enticing to read. It was an easy, fast read for me, and I was gratified to see even some data from the Bicep 2 experiment that I played a role in way back when. And I want to start there because you have had such a profound influence, not just on me as a physicist, but on all of physics and cosmology, you've interacted with and created

some of the greatest works that are pertinent, more pertinent than ever. In addition to your outreach. But I want to start there with today's news. I don't know if you heard it. It's neutrino news, and it comes out of the microboon experiment, recording this in late October 2021. I don't know when this will be out. But as of today, there is no evidence for sterile neutrinos from the microboon experiment.

And I wanted to kind of get your take on these things, because there are several anomalies that are described at lovingly intense levels of detail, but popular, accessible to a popular audience as well, which is rare that you have a book that appeals to experts like me and the lay audience. But anyway, what do you make of these proliferation of hints, of crises, of, you know, of anomalies? As Stephen Weinberg said, once physics thrives on crises. Luckily, today, there aren't so many. That was back in 1989. We have a, we're living in a golden age of crises.

What do you make of this? And in particular, the lack of finding of this sterile neutrino, you know, evident. or hint today? Well, I'm not up to date with the news about the sterile neutrino, but let me first make a very general comment in case people are wondering we've flipped from talking about a big hole in the universe to talking about one of the tiniest things we can imagine. The great point about our understanding of the universe is that it really combines the very large and the very small.

And so sometimes it said that the Big Bang was the greatest particle physics experiment ever conducted. And our understanding of how the universe is shaped, what it's made of, and what it's going to do, is, in large part, dependent on our understanding of quantum mechanics and particle physics and the physics of the very small, of which neutrinos form a part. And so when you talk about, you know, crises and anomalies, they really come in these two categories. Things like, you know, funny patch in the sky doesn't seem quite right, and also things in the realm of particle physics. And now let me just, again, be quite general about particle physics. There's something that we call the standard model. It's been around for some decades. And it's a sort of patch-up job.

It's a halfway house at an attempted unification of all the fundamental particles and forces of physics. And in a way, it's part of the program that began two and a half millennia ago in ancient increase. The idea that the universe is made of some fundamental building blocks and that everything that happens is simply the rearrangement of these building blocks. And that's all there is, the building blocks and the void. They call the building blocks atoms, but today we know the things we call atoms today are not the fundamental blocks, but we can go down a few layers. And then we get a whole bunch of things like quarks and leptons and, you know, we're bothered to enumerate them all, except some of them have quixotic names, and I, in the book, say that many physicists have their

favorite particle, of which mine is the graviton, but that's by-the-bye. The point is that this is not a totally disordered mishmash of particles and falses. There seems to be a mathematical unity there, and over the, well, the decades, really, there's been a sort of convergence in all these disparate things. We used to think when I was a student, there were particles being discovered, you know, every week. Nobody knew what to call them. Nobody understood how they fitted together. We now understand that there is an underlying mathematical scheme, but it, you know, there's a way to go yet. And some of the things we encounter, and have encountered for a while, don't fit into that scheme, don't fit into the standard model. One of these, for example, is neutrino mass. So,

We know of three types of neutrinos that we're definite about, and they are now known to have tiny masses. And the standard model of particle physics has no mechanism to assign them masses. So we know there is some physics beyond the standard model. The other area that is, I would say, is now an anomaly, is that there's a sort of firm belief. I mean, it's really a faith, I think, among theoretical physicists. that the two great classes of particles, fermions and bosons,

these are the particles of matter on the one hand and the particles that convey the forces of nature, on the other hand, that they should somehow be combined together into a single mathematical scheme. And that scheme was worked out years ago. It's called supersymmetry. And when the large Hadron Collider was built in Switzerland

to make the Higgs boson, famously did make it, There was a general expectation that in the lead-up to making the Higgs boson, it would also make supersymmetric partner particles. That is, for every boson there would be a corresponding lepton, and for every lepton there would be a corresponding boson, and that at least one of these particles would manifest itself. Well, that hasn't happened, and so what are we to make of that? Does it mean that supersymmetry is not a symmetry of nature, after all, or does it mean that we need a bigger and better accelerator in order to access the energies of which these super partners might appear?

Nobody knows that, but clearly that is one flaw in our understanding. There are others as well having to do with the possibility of new particles for which there is some suggestive evidence, nothing definitive. And just a general despair would be overstating it, but frustration that the force of nature that we most notice, which is gravitation, it's what keeps our feet on the ground, doesn't have a slick unification with the other forces of nature. So it's like an add-on. It's almost as if, you know, God created the universe and all these particles and three forces of nature and then as an afterthought throwing gravitation. but hadn't quite figured out how to combine it with the others. And we haven't figured that out,

although there's some famous candidate theories. So there's a lot still to be done, and a lot of things don't fit in. One other thing that I suppose I should mention is an obvious, I suppose, anomaly, but you read about it so often, it doesn't seem very anomalous. And that's dark matter, that we know the stuff of which you and I are made and the stars, atoms, basically, is only a tiny fraction of all the matter that is out there.

And what is called dark matter, well, there are plenty of theoretical candidates of what it might be, but so far nobody knows. We can see its effects from its gravitational pull. But again, we would hope that something like a dark matter particle, which would be very weakly interacting, be like neutrinos, but much more massive, would show up at the large Hadron Collider, some clue at least as to what dark matter might be. so far nothing. So we're left in the, literally in the dark, about dark matter, about neutrino masses and any possible additional neutrinos and a host of other auditors about particle physics, as well as

the large-scale structure of the universe. Somehow it's all got to be fitted together. And I want to make reference to a spin-off from the book, which describes even just the question of if there's a proliferation of particles and, you know, the famous words of Wolfgang Polly, you know, conceiver of the neutrino, you know, who ordered that. And then later, the saying that the Nobel Prize should go to the first person who doesn't discover a new particle. Now we've moved on from merely conjecturing and discovering new particles to actually invoking the existence of new forces.

So we hear a lot about fifth forces and so forth. And you even mentioned in the book, the G-minus two anomaly. etc. And I thought, you know, maybe we could get into a discussion of whether or not there are four forces, five forces. You say, the list of particles that I've introduced in this chapter raises the question of why. Is there a deeper reason for the list to be populated in just this way by just those particles and just those masses, electric charges and spins? And is there something magical about four, or as you just said, really three basic forces, rather than five or 50 or 500? I was taught Paul by, by, by, many eminent scientists in my career that you should never ask why as a scientist. You should only ask what, how, when, you know, etc. But you ask this question. I want to ask it back to you. What do you mean by why?

Is that a legitimate question for legitimate physicists such as yourself to even countenance ask it? Oh, well, of course, you're going to ask what you like. And I strongly encourage that scientists should ask the why question, even if we know that in coming up with explanations, we're really dealing with the how, because why is, of course, rather ill-defined term, but it very often carries the connotation of purpose. You know, why did you do that? And if we're caught out doing something, we shouldn't, then we come up with excuses. Right, or why can't I do that? And the parent always has to say, because, because I said so. That's right. But there is some.

a subtext to this. And it's one I've been involved with for my entire career, and the order I get, the more I feel it's significant, that human beings try to make sense of the world. We live in a universe which is not just, it appears,

a rag bag of odds and ends. It does appear to be a sort of coherent scheme of things. And indeed, you wouldn't embark on the scientific enterprise in the first place if you didn't feel that there was a sort of rational and intelligible order beneath the surface phenomena of nature.

And to dig out that order, this is a non-trivial thing. You don't just look around you and say, oh, I can see this, I can see that, I see how it all fits together. It's not apparent at all. So nobody would have ever discovered neutrinos or the Higgs boson just by casual inspection of the world. You never know they even exist in. So we have these arcane procedures of, you know, building weird machines and doing peculiar

stuff to matter that maybe has never been done before. and writing funny symbols on blackboards and bits of paper, and sort of figuring out how the world works, and it's been just spectacularly successful. We've had, well, three and a half centuries of really doing much more than just describing the world. That's not what theoretical physics does. It doesn't just give an account of the world.

It explains the world. It leads to an understanding. If you look at, for example, you could ask, here we go with a why question, Why are there electromagnetic waves? We know light is an electromagnetic waves. So why are there wave-like solutions of the equations? Well, you sit down, you look at the equations, you manipulate them, you solve them,

and out comes the familiar equation for a wave. And so that gives you an answer. Then you look at that and you think, aha, now I understand why there are electromagnetic waves. Well, in a sense, that's asking, you know, how is it that they come about? Okay, fair enough. But you see the point about asking the why questions. It leads you to that aha moment that, ah, I've got it now. I see how it's put together.

We would like to believe, I'm sure all of us are driven by this passion to explain the world, that there are reasons for why things are as they are, that there will be, you know, three generations of particles and all of these other things. that if we work a bit harder, there will be that aha moment. Now it will make sense. But, of course, it's only an act of faith. It may be that the universe doesn't actually make sense or it doesn't make sense to a human being.

After all, what we call common sense and what we arrive at as understanding is something that has been selected by evolution that we've evolved through natural selections, survive in the proverbial jungle. And yet we're equipped with this. cognitive ability to not just observe the world, but to understand it at this deeper level of reality. I consider that pretty stupendous. And it may be we just had a dream run that we've

had a few centuries where we've been really good at this and we're going to soon hit a brick wall and the whole enterprise will grind to a halt. I really hope that isn't the case. I really do think we can go further and that there is some underlying order that we're not quite getting. that we're missing at this stage. And that's for the next generation. We need help to understand what's going on. It's peak pollination season, and my business is scaling fast.

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GoogleFi Wireless is not subject to data traffic deprioritization during times of high network usage. And when we think about, you know, kind of the goals and the teleological driven physics, you know, oftentimes we're at a loss because we want to connect, you know, the reasons, as you're saying, for these phenomena with something that we can, A, comprehend and maybe even B measure. But I want to ask, you know, you've had such an illustrious career. And I've never seen you as a fad or, you know, fashionable chaser as, as our friend Sir Roger Penrose calls, you know, fads and fantasies and fallacies and physics, past guest on the show. And I want to ask you, though, as a theorist, you know, speaking to an experimentalist like me, how do you know when to take a hint from an experimentalist seriously? In other words, we come up with experiments to test theories primarily. Sometimes we discover things serendipitously, like the CMB ball sitting behind me was discovered serendipitously in 1965, as you talk about.

But nevertheless, most of what we do is driven by some teleological purpose, that physicists, such as yourself and other colleagues, have come up with ideas for how the universe, how that pattern got there. And we set out to design tests to unravel perhaps the relic radiation in the form of gravitational waves to maybe indicate the presence of a hyperluminal expansion called inflation. We'll get into inflation and your contributions to it in a minute. But what is it that allows you to have the taste, the good taste and the good sense that you have, as I hope to instill in my students to have good taste to know which theories to investigate?

How do you know when to risk your credibility on something like, you know, the G-minus 2? Or recently there was a hint in my field of cosmic biorefringence and polarization. rotation at the 2.5 Sigma level. Last week, there was a hint from the Large Hadron Collider Beauty Experiment, LHC, lowercase B. We'll be talking with Harry Cliff about that soon. And that was like a 1.5 sigma effect. And yet, when Bicep came out, there were 700 papers, you know, explaining how we could have gotten such a large tensor to scale a ratio. None by you, I should point out. But anyway, Paul, can you explain your rub—is there a rubric that an eminent person such as yourself would use to delineate what is worth my, you know, spending or wasting a considerable amount of my most precious resource, my time, on a new experimental hint? Right. Well, there's a pompous answer to that, and it's the application of Bayes rule. Of course, so Bayes rule tells you you have to assign some prior probability that a particular theory or idea is going to be correct, and then you update it in the light of the experiment. And I'll give you a very simple example that I'm often involved in, that, you know, have we discovered life on Mars? So, you know, wouldn't that be great?

And I'm often asked, you know, there's some little hints of evidence. Does that mean there's life on Mars? And I say, well, you know, if you do Bayes rule, in my view, because Earth and Mars trade rocks all the time, they can trade microbes. And so I think it's almost inevitable that there will be life on Mars if only because he got there from Earth. But if you think that a life arose independently on Earth and Mars, well, the probability of life arising de novo from a mishmash of chemicals could be exceedingly small, in which case you'd need very strong evidence that you had found life on Mars. So that's part of it. In practice, of course, unlike you, I have the luxury of being able to do cancer biology in the morning, cosmology in the

afternoon and quantum physics in the evening. And my research moves at the speed of thought. And I don't need to apply for a large research grant and build equipment and hire people to service the lab and all that sort of stuff. And so that makes it very easy to be agile. But in terms of making decisions, so there's a large element of luck, I have to say. So I worked in, let me just give you a little bit of, you know, you can tell how old I am because, you know, I keep reminiscing about the glory days of the past. But it actually is significant in answering your question because I went to Cambridge University

as a postdoc of Fred Hoyle, the cosmologist, in 1970. And, you know, the lads down the corridor, and there was only one female postdoc at that time, included Stephen Hawking and Martin Reese and Jim Hartle, You know, the sort of roll call of now the great and the good. But they were just my colleagues and working on various things. And this is relevant to answer your question in two ways, because one is that Martin Rees was strongly influential on me for the reason that he occupies that sort of intermediate position between theory and in astronomers' cases, more observation than experiment. And I would always figure, can I take this seriously?

you know, what about that point of view? And I would go to him, and I would feel that if he said it's okay, take it seriously, or if he said, don't take it seriously, that was very good. So having those people who can act as a breach between the hard end of the science and of the experiment and observation and the sort of airy-fairy theory, those people are extremely useful. and I'm really grateful and he remains a good friend of mine all these years on. And then the other person, Stephen Hawking, that is a curious thing because at that time, I was interested.

From my PhD, I worked on something called the Wheeler Feynman theory of electrodynamics. So this is an attempt to explain why we see only retarded electromagnetic radiation, roughly speaking, why radio waves are received after their center, not before, even though the fundamental equations of electromagnetism are time-symmetric. And Fred Hoyle, who I went to work with, had connected that through this Wheeler-Finement theory of electrodynamics, which is time-symmetric, has advanced and retarded waves, had connected it up with cosmology and the structure of the universe, and he thought that only in the steady-state theory would you get retarded electromagnetic waves.

Turned out that wasn't true, but that's not the point. The point is that that's what I worked on for my PhD, and it connected the large and the small. I thought it was wonderful that something that told us about radio emissions from the local station would connect to the structure of the universe. Same with Mach's principle. I was always fascinating. So then towards the end of my PhD, which is in the late 1960s,

I noticed a number of people working on a very, obscure backwater of science, which was, if you apply quantum physics, in particular quantum field theory, in an expanding universe, it looked like particles got created. So I thought, well, is that how all the matter came to the universe in the Big Bang? You know, was it just some sort of quantum vacuum disturbance, something like that? That turns out that wasn't the case, but I was sort of intrigued. but the effect seemed to be so tiny that it didn't look like anyone else would be interested. And so I worked on particle creation in expanding universes, a famous paper by Leonard Parker at that time,

and also applying quantum physics to black holes. I thought, you know, there might be some value in that, but it all seemed incredibly theoretical. And this was totally transformed when Stephen Hawking, then in 1974 came up with his idea that black holes are not black, but glow with heat radiation by applying quantum physics to it. And that was something that sort of threw me at the time, because I thought, well, I've been thinking about this for a little while. I'd never discussed that with Stephen, but we had talked a little bit about the particle creation and expanding universes.

But really this sort of came out of the blue. And I thought, well, how can it be the case? Because a black hole, you know, the Schwarzschild solution of a black hole is time symmetric, how can there be a flux of radiation? Because I was already working on my book, the physics of time asymmetry, the arrow of time. So it seemed to sort of fly in the face of that. And it took me a few weeks of head scratching before I could get that aha moment, now I see what's going on here, that there is a, you break the time symmetry of the system with the collapse of the star, you see. So even though a black hole might have been around for billions of years and is glowing, that kind of,

glow reflects the disruption to the quantum vacuum billions of years ago. It's an extraordinary thing that it's like the fading grin at the Cheshire cat living on after all that time. It took a while to figure that out. But you see, because I was sort of in on the ground floor of that, and then worked, I went to King's College in London, to the mathematics department, had a lot of good students and postdocs, and we worked on going beyond what Leonard Parker had done and trying to work out You know, the big problem, you can talk in quantum mechanics, you can use particle language.

People do. They talk about particles, being created from the vacuum and all that sort of stuff. But if you're interested in gravitation, you don't want particles. What you want is this thing called the stress-energy momentum tensor. Think energy, really. That mass gravitates energy's form of mass. It's more complicated than that in Einstein's general theory of relativity. the whole stress energy momentum tensor you need.

And when you work that out in quantum physics, you find you get the unhappy answer of infinity. And the reason for that is just because even in a vacuum, there's a sort of irreducible level of quantum energy, which is flitting around, and when you tot it all up, it's actually divergence, infinite. So we had to develop some techniques for taming that, for getting sensible, final. had results. And again, it looked to us in the, I'm talking mid-70s, late 70s, as very much a theoretical exercise with largely thinking about how do you explain how black holes lose mass, because negative energy flows in, as we found, but also, you know, applying it to the expanding

universe, just, you know, completing the program that Leonard Parker began. And it was really more, I still thought it was a backwater, more of a sort of elegant, enterprise than anything that would have application. And then bang, in the 1980s, along came the inflationary scenario of the early universe. It leapt in size by an enormous factor in the first split second, a phase of exponential expansion. And we'd done all that stuff. We'd looked at a quantum vacuum in an expanding, exponentially expanding space time, sort of ready with the answer. And so I was very fortunate that these things turned out to find application. And to be perfectly honest, by the time all this was settling down in the mid-80s

and everyone was dashing off into string theory. And I thought about that and my colleagues seemed obsessed with it. And I really didn't want to go down that path. And then I began to turn my attention to other topics. I thought, well, I'm sort of bored 10 and 15 years doing quantum fields in curve space. I started getting interested in the origin of life. And I must say in passing, and I'm talking a lot here, but in passing, that was also Martin Rees.

I have to thank for that. Because in 1983, he held a meeting in Cambridge called From Matter to Life. And of course, I read Schrodinger's little book about what is life and viewed through the eyes of a physicist. It looks like magic. And after that conference, I thought, well, it's even more like magic than I thought. But I don't believe in magic. so there have to be mechanisms we don't understand.

The physics of living matter is something that needs a lot more work and a lot more thought. And that became a sort of hobby that fast forward to now, it's very much dominating my thoughts. So I've been able to sort of move all across the map. And maybe that's been to my disadvantage. Maybe if I stayed in some narrow area and just kept plugging away and reemphasizing contributions and so on, You know, I might have had greater glory, if that's what we're after. I don't know what we're after as practicing scientists. But, you know, I'm really pleased to have such diverse interests and to be able to move across these different subjects and disciplines.

So could you clarify for us, you know, the rubric that one might apply, at least deriving from what you just said or distilling it, is really one based on kind of discursive curiosity. It seems to me that you're just relentlessly curious. And I always say that, you know, passion is kind of like a spark. It's important to ignite, you know, a rocket or something. But the real fuel is curiosity. And it seems like the thing that characterized you said at the beginning of this answer was, you know, curiosity, everything from cancer to the cosmos and everything in between. But there's always a through line, which I think I see in you a reluctance to work on, I wouldn't say trivial in the sense of boring or unimportant. But you have done work that's foundational and fundamental, as you just mentioned, but you like to take on the very grand.

And you're not averse to talking about big picture topics in philosophy and even theology, which we'll get into. Not that you're the only physicist. I mean, many, many from Einstein, Galileo, Newton, et cetera, have gotten into these. But, you know, from the standpoint of a, you know, of a practicing work-a-day theorist, at some level, it's important to go deep and sometimes you have to go abroad. And I guess the question is, are you unique? Is there something to be learned from Paul Davies? Or is it just that you have this gift, this discursive curiosity, as I called it?

Or are there ways to, for my audience and people that might be young, aspiring theoretical or experimental physicists, is there a tool? Is there a technique to find the nugget of the most interesting kernel that one could pursue? or is it sometimes just a matter of serendipity or luck? Well, as I mentioned, there is an element of luck, but there are certain guiding principles. One of these is, your curiosity is, of course, important. I'm very tolerant of pretty way out ideas.

And you can be tolerant but skeptical. It's really important you say, well, I don't think this is actually right. But, you know, tell me how you think it is, and, you know, I will pay some attention. So that's one thing. The other thing is for young people. And I think it's probably worse now than when I was embarking on my career, is that if you sort of go off into the weeds and don't establish a reputation in some sort of mainstream discipline, it's actually very hard to build a career.

And I benefit very greatly from my collaboration here at Arizona State University with Sarah Walker. And Sarah, I could tell, I knew her as a PhD student, I could tell she shared my passion for, you know, all of these wonderful questions. And she came on an ASA astrobiology postdoc to work with me. And we wanted to solve the problem of life's origin, and we're still working on that. But the advice I gave her, and I think it's very sound and it's worked very well in her case, is that, you know, devote about half of your time to sort of just good, solid contributions at a technical level, I mean, in her case it's all theory, at a technical level to, you know, some sort of mainstream topic that will get, the papers will be published, people pay attention and so on. Then the other half, you can sort of go off into this,

you know, never, never land of these really big questions. And she's done that very well. I saw in her, 10 years ago, a younger version of myself at that age. I recognized. you know, that sort of passion to really get to grips of things. But it's not just a matter of, well, you follow up somebody else's ideas. We need new ideas. She's been very good at saying, we're thinking about this all the wrong way. We should, this is the concept we need, or we should try this out, or try that way of looking at it. And so that would be my advice to any dreamers who are listening to these words,

that they don't neglect your sort of mainstream stuff. And for me, that worked well. The other thing is, of course, in any sort of university setting, there is a small matter of students. They're around, they're important. I love them. They have to be taught. And so some attention needs to be given to just those sort of housekeeping issues,

giving good, inspiring lectures, well put together, and all the other sort of university administration things. So that aspect of one's career can't be neglected. There are very few scientists who have really made it big time by sort of going off and living lives as hermits and doing groundbreaking work. If you're part of the community, you've got to play by the community rules. Very good. I very much appreciate that, and I agree about Sarah. She's an inspiration to me, and she's just so tremendously energetic and thoughtful and considerate. And like you, as you say, she's, well, she's influencing you, so I don't think it's patronizing in any way, but she is only interested in the biggest picture topics.

And I really respect that. And I've had her colleague on Lee Kronin from Glasgow, and I hope to have Sarah on as well. I want to talk about some of the deep dives that we got into in this book. And you have just, again, you know, I'm sorry to just keep praising you with high praise, not faint praise, but strong praise. But you have a true gift that explaining very, very abstract concepts like CP violation, things in my audience, because they're the most brilliant audience in the known universe, have seen and encountered and even had great, great conversations about. I want to talk about these departures from, you know, again, anomalies that don't. seem to make sense. And here's a line of logic that I've been using, and maybe you can disabuse me of it. But the fact that the laws of nature aren't perfectly symmetric. And in a certain

sense, we're trying to enforce things like supersymmetry and so forth, which has to date not really panned out, according to the rubric you outlined two or three questions ago, we should apply Bays' rule. And so I wonder, is it a fool's errand to try to impose kind of this need for beauty, symmetry, parsimony, economy, on the laws of nature, when we know that they're actually in violation of it on a regular basis. And in fact, you know, if I had a bet on it, I might not even suspect that Lorentz's invariance holds over the entirety of the universe. So what do you make of this desire to, I mean, if an alien knew the answer and was looking at our theories and say, why are you looking for something so symmetric? We know the universe isn't symmetric.

And so why are you trying to cram all these theories into one, you know, God equation, which we'll get to in a bit. Do you think that that's a fools, Aaron? Do you think that's more of a projection of physicists as human beings rather than as purely scientific entities? Or do you think there's something to be gained for looking for symmetry, beauty, and parsimony? Well, that's a very important question. And it's certainly true that over the past two or three hundred years, the application of Occam's Razor has really manifested itself by looking for symmetries, it's just sometimes as simplifying features in an approximation. And there's always this danger that something that seems to work so well in so many ways,

we will take a sort of founding principle of the nature of reality. but it's clear that if the universe was symmetric in all its aspects, that we wouldn't be here, that you have to break symmetries to get structure. And the one that, of course, most intrigued me, because it goes right back to my PhD thesis, was the time reversal symmetry breaking. And it's, again, in case of, well, who needs that? Yeah.

We can break the symmetry of the world by setting the universe up in an order. orderly state and letting the second or thermodynamics do the rest. Why do we need to break to have T-violation down at the particle physics level? Nobody's really ever connected those two up. Nobody has ever said, well, T-violation in particle physics explains the ordered nature of the universe just after the Big Bang. Some people have dabbled around in that. So it remains one of these sort of auditors. So why is it there? And it could just be, again, that we've had a dream run of success, We're in a similar situation, I think, with linearity. So the great advances in physics in the 19th century stemmed in large part from the fact that many everyday phenomena are approximately linear and you can go a long way using linear differential equations and free-air analysis, those sorts of things.

And so that works well for heat conduction and wave motion and a whole bunch of things that are important. But in the last 50 years or so, the importance of non-linear phenomena have become very prominent, and in particular chaos theory and various forms of complexity, which have become popular, but difficult to study because they're not tractable by these simple scientific methods, simple equations. And so that raises the interesting question. Have we just cherry-picked the stuff that we're good at? And that we say physics is amazing. Explain all these things.

Look, we know the secrets of the universe, and we've got all these equations. But we're just defining success in terms of this rather small subset of phenomena. We're surrounded by all sorts of things we really don't understand, including things like turbulence, which it boils down to it is a bottle, half full or half empty. And just quite how much longer we can have success with essentially 19th century methods is an interesting thought.

Are we getting to the point where we simply can't do that? I mentioned that I've become sort of obsessed with life and the physics of living matter and so on. I don't think traditional laws of physics linear otherwise are a good fit to the nature of life. To understand life, we need to organize data about the world in a completely different way from underlying laws and initial and boundary conditions. You can try doing that, but you don't get very far. So there must be another way of doing science, which we need to come up with.

Some people think this is also true in cosmology, because if you think there's only one universe, and we can argue about that, but if there is only one universe, but if there is only one, we can And what does it mean to say we apply the laws of physics to the universe? Because if there's only one of it, the whole idea of laws is that they're supposed to be a whole class of similar systems and you can have different initial conditions and so on. If there's only one universe, can we meaningfully apply laws to it or does it need some other way of attack? So, you know, I think we might be approaching the point where we need some radically new thinking, not just. just about the particular equations that we use, but at a deeper level, the way we organize our facts about the world, maybe after three or four hundred years, we need a different way

of thinking about it. Yeah, I wanted to move into that subject, perhaps, and that'll lead us into a discussion of the laws of nature in a universe that is a set of elements within the multiverse. You talk a lot in the book about historical approach to our understanding of the cosmos and even the great debates of previous centuries and even of this current century. And I would say that one of the most prominent among them is, of course, the existence of the multiverse and the concomitant conjecture of a string landscape, perhaps. These are fascinating.

These are very delightful to consider and to contemplate. Until you start to think, you know, are people taking this really seriously? And you, of course, have a very famous article that was in the New York Times, and we'll talk about that. And we talk about God, but specifically relating to the multiverse, which is an allied outcome of most theories of inflation. In other words, the theory that there must be an infinity or at least a very large number of universes, as you say, in order to explain the properties of the features of the universe we do see is just as ad hoc as invoking an unseen creator. The multiverse theory may be dressed up in scientific language, but in essence it requires the same leap of faith. And so I want to get into that, this statement about faith and God and so forth. But first I want to take a step back.

On a personal level, you made fundamental contributions to the theory of inflation, which now comes with this ad hoc addition of the multiverse. First, can you explain this foundational discovery that you and Bunch, I forget what Bunch's first name is, but you can come. Timothy Bunch. Timothy Bunch. the Bunch Davies vacuum state. What is that?

How did you come upon it? And what does it have to do with inflation? Right. So I touched on this a little bit earlier in two ways. One is that we wanted in the late 1970s to try to understand the quantum vacuum in the presence of a gravitational field. And Lina Parker had blazed the trail by looking at particle creation and expanding universes. but there were a lot of unclear aspects at that time.

We didn't quite know how to think about a lot of these things. And the mathematical techniques to regularize, as we say, the stress energy and momentum tends, it hadn't really been worked out. A lot of people were working on that, and that got hammered out in the 1970s. But as I mentioned earlier, that for young people, it's great for them to have dreamy thoughts about the big questions, but they also have to have some solid accomplishments. So the one burden upon anybody who has a student, is you've got to give them something that is not only interesting,

but that they can work out. And so Tim needed his PhD. We needed to find a system, a type of universe and a type of quantum field, where the equations can be solved, and Tim would get his degree. And what appealed to us was DeCyter Space. Now, let me just say, DeCyter Space is a space that doubles in size in a fixed time. So it's exponentially expanding. It was suggested by Willem DeCitter in, I think, 1917,

pretty early on just after Einstein's general theory of relativity. And it was a sort of toy model. The extraordinary thing about DeCitter's spaces, it's got the same number of symmetries, here we go again, as ordinary Minkowski space, flat space time. And so the equations of quantum physics are just as easy to solve in the city space as they would be in the lab. Having said that just as easy to solve, the solutions are less familiar functions. But the technique for solving it is just as easy.

So Tim worked through all of that and Julie got his PhD. and we didn't know at that time that De Sitter Space would play such a prominent role. It seems pretty clear from the astronomical evidence that we weren't living in DeSiterspace. It looked like the universe was decelerating. And so two things then happened over some decades. The first is that inflation came along,

and inflation means a phase of exponential expansion, extremely rapid in the first split second of the universe. And that was posited by Andre Lindy, Alex Valenkin and others in the early 1980s, as a way of explaining why the universe looks, as I said early, like the perfect baby, so smooth and unblemished and uniform. That nicely explains it. And so it was an attempt to get around that mystery. But, of course, it was precisely this exponential expansion that we had worked on

and we had these equations ready for. And if you believe, because the e-folding time for this exponential expansion is stupendously small, 10 to minus 34 seconds or something, quantum effects are going to be all important. And so here we are with quantum effects in an expanding universe. When inflation came to an end, because it has ended, and morphed into a traditional decelerating slow expansion, When that happened, the quantum fluctuations during that inflationary phase got sort of frozen in and writ large and written in the sky imprinted in the pattern in the background, the cosmic microwave background radiation. It's sort of up there for everyone to see.

If you believe this, those are quantum fluctuations in the sky, but it's a snapshot of them. They're not fluctuating anymore. And so that's really how that came to exist. Then the other thing that happened, of course, is that in the late 1990s, astronomers discovered that maybe the universe isn't decelerating after all, but it's actually the expansion rate speeding up on that we're now embarking on another phase of exponential expansion, but now with an e-folding time of billions of years and not a tiny fraction of a second. So suddenly, you know, de Sitter space, which was a curiosity in the 70s,

turns out to have at least two applications to modern physics. So that's how I came to be involved. And nowadays we hear a lot, or at least we did up until 2018 when sadly your friend and colleague Stephen Hawking passed away. We heard a lot about these bets involving black holes and information, and you talk a little bit about the information paradox. I always don't like to reveal all the contents of the book because I want everybody to buy a copy of it in both hard copy and in digital media formats as I have. But I want to go back to that because, as I understand it, Stephen would concede all these bets. And as Sir Roger Penrose said once to me, you know, the good thing about making a bet with Stephen is that you could always be on his side,

no matter which side you chose. But Stephen would concede these bets, for example, by congenre, as Juan Maldesana has done, that you could solve the black hole information loss paradox, and you could do so, but you can only do so in anti-dissitter space. As far as I know, we don't live in anti-desciter space. So why did he concede these bets on the basis of something that not only is falsifiable, but was false is falsified? Why would you think that he would concede such things? Was it merely for attention?

I hope not. But how do you reconcile this fascination with all these things like, you know, extra dimensions and so forth and anti-desider space when we have zero evidence and maybe contradictory evidence to those claims? Well, first of all, you know, Stephen and the bet. So he was very fond of doing U-turns and I loved him for it. The one that I was most involved in myself is when for a time he thought that if the universe recontracts, arrow of time would be reversed. And seeing as I'd written a PhD thesis on that, I thought, oh, not that again, because sometimes this idea that we live in a cyclic universe, cycle in time, a groundhog day type universe. It's referred to by anthropologists as the myth of the eternal return. And so I was

fond of saying, oh, the eternal return has made another return. And the number of scientists who got caught up on this. So the first I knew was Tommy Gold. And then John Wheeler, who would sometimes talk about the turning of the tide, wonderful metaphor, typical Wheeler. And then, you know, along came Stephen saying that this might be the case. And then Murray Gellman and Jim Hartle. But, you know, this is an idea that won't go away. But I have not just theoretical reasons for objecting to it. I think there are observational reasons why we shouldn't take it too seriously. But in that particular case, Stephen did retract.

I was there at the retraction. It was in Spain, a conference there, and he gave a lecture entitled, My Greatest Mistake, echoing Einstein whose rejection of the cosmological constant was his greatest mistake. And so Stephen flipped

around on that. I'm not sure that any bed, I didn't take the bet. I didn't think to place a bet on that one. But the black, coming to the black hole case, and that was a long-standing bet. And it was always a mystery, you see, way back in the 70s. That's, okay, black holes glow with heat. How does

the energy get out of the black hole? Because nothing's supposed to come out of a black hole. That seemed a bit strange. And that's something I've already alluded to, that my colleagues and I, and I must thank Larry Ford and Stephen Fulling and Bill Unruh and others who helped work out the stress energy momentum tense around a black hole. And we showed that the, what happens is you have a flux of negative energy flowing into the black hole, not positive energy coming out. And there's negative energy around all the time. What it means is that if you take the energy of the quantum vacuum in just sort of ordinary vacuum in the lab or something like that, if you can contrive a state of affairs where the energy is less than that, then we would call

that negative energy. And a very well-known example is the Casimir effect. You have a couple of mirrors facing each other, and the energy of the vacuum between those mirrors is a little bit less than what it would be if the mirrors weren't there. So that idea is not so bad. Gravity can produce negative energies. So the gravity of the earth produces a cloud of negative energy around it. It's tiny. But around a black hole, it's really quite big. And Paul, is it semantic in that, you know, if we called it positive, we'd be asking why is there positive energy flowing into a blockhole? Or is it, you know, Ben Franklin, you know, called the charge carrier, and it was a negative charge carrier and the electron. Is it, is a semantic,

or is there something truly, you know, fundamental about the aspect of it being negative as opposed to positive? Right. There is. So when we're in high school, we were told, well, the zero of energy is arbitrary and it's energy differences, only that you can measure. And that's true until you come to gravitation. And if what you say is, well, energy gravitates, then that's a physical effect. And you can say, will this particular state exert a gravity bend in space time, basically?

So if you define flat space time, so you're not bent, then the quantum vacuum in flat space time has got to be defined as zero energy. I think that's a very reasonable thing. So anything that is less than that, we would call negative energy. And gravitational fields can make it negative,

or positive. So it has both of those effects. Around a black hole, it's negative, it flows in, and it pays for the hawking radiation. And so that was a fairly simple one. But then there was this other one. Well, you know, what happens to the information that falls down a black hole, or the stuff that falls in, if you have a star, or if you have a black hole there and you throw in, the famous example, throw in some encyclopedias, you know, what happens to all that information. The feeling was in the 70s it's swallowed up forever, it's never going to come back, and that information is simply lost down the black hole. That didn't seem so shocking because Hawking and Penrose and others told us that there were singularities inside the black hole

and a singularity is an age of space-time, boundary. So if information hit that boundary, it would cease to exist, at least in our space time, gone. That's it. It didn't seem so shocking. But But this didn't sit well with people from a particle physics background and now a string theory background, but they don't like the idea of gravitation, space-time structure, calling the shots. They want quantum mechanics to call the shots. They want that to be the founding set of principles that govern the universe. And quantum mechanics, there's a simple theorem that information can't be created or destroyed, defined in a certain way. And, you know, what were we going to do about that?

Well, a lot of people at the time thought, and I think they still do, but Blackholt simply violate that quantum principle. But Stephen, towards the end of his career, decided to do one of his U-terms, and having said, well, it was violated, then said, well, maybe there is a way for it to get out. But the problem here is that when you look at this as a technical, challenge. You want to solve the back reaction of a quantum field on a black hole and see how it shrinks and what happens, what its end state might be. Well, the simple answer is we don't have a good theory of quantum gravitation that can handle that very dense final state. Would it be

singular? Will it be something else? What will happen to it when the black hole evaporates? We don't know how to do those calculations. But we do know from the work of Dom Page that you hit a problem long before the black hole shrinks down to a plank size or something like that, you hit a problem about the headcounts of all the bits of information. And so there is something we don't fully understand. And the mathematical models that people have appealed to to say, well, the information gets out by this or that mechanism are all extremely idealized and totally unrealistic cases, which, which have got a great deal of appeal because people can manipulate the equations. I think this is still one of the great unsolved problems of theoretical physics. It's one of the things I alluded to in the book as we need the next generation of young people to tackle that one.

And if we also look at the concomitant realization or most wonderful realization of his life, according to Albert Einstein was that a freely falling observer would experience no gravitational field. The corollary that you and Bill Unruh and maybe it was Paige, I forget who, came up with, was that you could actually detect acceleration in the universe via an equivalent to the hawking radiation effect. I wonder if we can talk a little bit about that. I've developed a great interest nowadays in thinking about the possibility that

perhaps the universe doesn't respect Lorentzian variance, and why that shouldn't be thought of us so sacrosanct without some further degree of evidence. It's a nice shortcut, a hack, and it certainly seems to hold locally, but as we know, things that hold locally don't often hold globally. So as Einstein, you know, called this the happiest thought of his life. And I, by the way, I think that that is a reason that we should never fear artificially intelligent physicists, because I don't know, first of all, if an artificial intelligence could experience happiness and therefore come up with the strong equivalence principle, or the weak equivalence principle. But I also don't know if it could experience, you know, what free fall really would mean,

because it's sort of a visceral sensation attached to a body. So I could probably debate that with Noam Chomsky again. But I want to ask you, it's sort of taken for granted that motion is relative since the of Galileo and the first relativistic discovery that you talk about in eating the universe, what's eating the universe. But that acceleration could be absolute. Can you explain and walk us through that logic? How can velocity be strictly, you know, strictly not, strictly relative, but acceleration could be absolute? How could those two, after all, isn't one just a time derivative of the other? Well, I touched on this a little bit earlier when I talked about Mach's principle.

And so this really goes right back to the founding fathers of modern physics, Galileo, Newton, Leibniz, Descartes, and others about the nature of motion. And I think everybody came to accept that linear motion or unaccelerated motion is purely relative. You can't sit in empty space and measure your speed relative to space itself. But acceleration seems quite different because you feel it. And the example I give in the book, you're flying at some altitude at a steady rate and you fall asleep, as I often do on takeoff. I can't tell if you're static on the ground or whether you're actually 500 miles an hour in the air. I do that too, but I'm a pilot, so it's a little more dangerous. Ah, right, right. Don't fall asleep then.

but you know if you hit turbulence you know immediately you can feel it and so make every get together chill this memorial day get up to an extra thousand dollars off select top brand appliances like LG plus get free delivery at the Home Depot tackle pool towels and camp laundry with a large capacity washer and host in style with the fridge serving craft ice mini craft ice cube dice and crushed ice shop appliance savings now through June 3rd at the Hallm Depot. Offer valid May 14th through June 3rd, US only, free delivery on appliance purchases of $998 or more. See Store Online for details. For Newton, something like rotation, he regarded as absolute. The earth bulges at the equator, and he felt that that would be true even in an empty universe. But there's a long alternative tradition which says no even rotation

and acceleration more generally has to be gauged against the distant matter in the universe. after all, the world goes round, it bulges at the equator, and we look up at the sky, and the stars are going round. And so we can tell the earth is spinning by looking at the stars, but we can also tell it's spinning by measuring how wide it is around the waist. And so these are obviously connected through Newton's equations. But this idea that maybe even accelerated motion is relative to distant matter in the universe continues. And it went, well, Ernst Mahz gave us the famous Mach numbers, believed that there was a way of somehow incorporating the local, technical terms, compass of inertia, but I mean basically these forces, like centrifugal force,

could be attributed to the distant matter in the universe. And I mentioned about my work in my PhD, the wheel of fireman theory of electrodynamics, which has, it's a time symmetric thing where radiation goes out into the universe, but advanced radiation comes back at you, and you're coupling what's happening in the radio station to what's happening in the distant matter. Marx's principle is a similar sort of thing. If you can make it work, it's a way of connecting local physics to the stars, you know, to put it romantically. The trouble is nobody's really been able to make it work terribly well.

Einstein was a great fan of it, hoped it would be there in his general theory of relativity, but it's not. There's something called the Kerr solution of rotating black holes, and it's empty space outside of this black hole. And so there's no other matter. And yet, the Kerr solution has, you've put a test particle, and you can measure the rotation of this spinning black hole. So this is unfinished business, but I don't know if you want me to connect it to the story of accelerating.

I would, I would. I would like to know how could we actually measure our absolute acceleration using the effect that you and colleagues discover? Well, you see, we were all brought up on this idea that gravitation and acceleration were the same, which is, of course, as you say, debatable, but I didn't need to think too much about it. So when Stephen Hawking announced his black hole result, and I thought, how can that be? I'm a bit skeptical. Can I think, and I wasn't sure I understood the calculation, that can I think of a simpler example,

then I thought, well, you know, what about uniform acceleration? And I was already familiar with Ringler's textbook on uniformly accelerating observers, and you have a horizon there, just like it's a black hole horizon. And I knew of the work of Stephen Fulling, who then became a close colleague of mine, in which he looked at quantum fields in the Rindler coordinate system. And I thought, well, I just need some sort of simple argument that ties all this together that would suggest that an accelerating observer would basically see hawking radiation in the same way. and I produced and published and published that.

I didn't think anybody would pay too much attention. Funny little postscript, and here's a lesson for students. I also thought I knew, of course, from simple enough physics that de-sitter space would have a similar coordinate system and there would be a temperature of the sitter space. I remember sitting there. In those days, I didn't even have an office, didn't have a desk. I was sitting at my wife's dressing table.

And I thought, well, yes, okay, so I can work out temperature to sitterspace. What is it? Well, what do I put in for the rate, for the Hubble constant? And I put in, you know, the currently measured value. And out came the temperature of, I don't know, 10 to the minus 30 degrees or something. Well, no one would be interested in that. I won't bother to mention it. So I wrote the paper and left out the decider space bit.

And then the next year, Bill Unruh wrote, sort of discovered the same effect by different arguments involving a model of a somewhat cumbersome model in those days of an accelerated detector that would go click, click, click. And then Bryce DeWitt did a very nice job producing a, you know, more usable model of an accelerating detector. And, you know, the rest is history, as they say, this turnout. It's still unclear to me whether anybody has experimentally verified this acceleration effect from time time I get papers and claims that this is sort of done either directly or indirectly. The numbers are very small. You need a very, very high acceleration to have a detectable, you know, one degree or something.

But I think we're sort of, we're beginning to see hints of it anyway. So that's how I came into it. Looking back on it, it didn't seem any big deal at the time. But some people think it's important. Dennis Shiamer, I might say, who was the PhD thesis advisor of Hawking and Peros and many other Martin Reeds as well. He was very fond of this and he thought this was very significant that this acceleration effect really told us something very deep about the nature of the universe.

And I think that dream lives on, but several decades on from this one. work in the sectors and not sure how much more progress we've made. Yeah, and that's somewhat delightful in some ways, but I think these things really elicit. The biggest picture questions that human beings might be capable of answering or asking, at least, maybe not answering, but at least asking them. And I wanted to segue that into a talk about God, if you'll indulge me with some forbearance. You and I have talked in person when I visited you and colleagues at Arizona State University, where you have been for many years and continue to contribute in public fora and in research and education as well in such a monumental fashion.

But we chatted on a walk about this notion of life as sort of information. And I wonder if, you know, you're familiar with this famous monograph by Schrodinger, what is life? And, you know, he comes up with some ideas and he even mentions, you know, molecular basis that, you know, was wrong. It was a crystal that was a periodic, not a double helix of nucleotides. But I wonder if you could recapitulate a little bit of your thoughts on life as information, which I believe you touched upon in a previous book. But what is life to answer the, if you can answer Schrodinger's question, left unanswered in his book? Well, we've gone from God to life. So let's tell you.

We'll go back to God. Don't worry. It's a big one. But the life is. So I read that book when I was a student, and I thought, hmm, yeah, it does seem, life does seem pretty remarkable to a physicist. I think I said earlier, it's like magic. But, you know, what do we need?

Now, his aperiodic crystal actually turned out to be very prescient, because although he didn't say, well, it's a double helical structure, he was exactly right that what life needs, what genetic information needs. It needs some stability, if it's to be handed on from one generation to the next, shouldn't be firmly disrupted. So it needs to be, have the property, stable property of a crystal, needs to lock in its structure.

But it needs, crystals don't contain any information. They're just periodic structures. And so what you need to encode information is to have, to break the symmetry, as we've talked about earlier. and you have irregularities of some sort. And so the idea of an a periodic crystal is exactly, it's an information-rich, stable molecule. It's just what DNA is.

And because of the four-letter alphabet of DNA, you can encode a staggering amount of information in a strand of DNA, but it is relatively stable. It's not disrupted by thermal fluctuations of room temperature. So that was pretty good. But I don't think he answered the question. I think he hoped that somehow quantum mechanics would come to the rescue.

After all quantum mechanics explains all other matter, but it sort of curiously can't explain living matter. But rather more venturously, and I take this as the jumping off point from my own recent interests, he said that we must be prepared to find a new kind of physical law prevailing in it by it he meant living systems. Not just a new physical law, not just alongside Maxwell's equations. and so forth, we've got, you know, Schroding is a life equation, a new kind of physical law. And as I said earlier, I think that traditional laws of physics are not a good fit in biology.

For reasons we could talk about at length, but one of them has to do with the separation of scales by which we make so much progress in most areas of physics. Take solar physics, for example, we can talk about turbulence in the, in the, in the, photosphere without worrying about the nuclear reactions taking place in the core and so forth. So we can sort of separate the scales out very well. With life, you can't do that. There's top up and top down and bottom up causation, and it's all a tangled sort of self-consistent mess. But to actually directly answer your question, what is life, I would say it's a sort of catchphrase,

but a lot of people use that life is chemistry plus information. The essential thing about life is that the information is not just any old mishmash of bits. It's actually, I can say that again, it's not any mishmash of bits, it's actually information which is organized and which can bring about the organization of matter. In other words, it serves a management role. And so if you measure it. information in bits, as Shannon taught us many decades ago, it doesn't somehow capture the contextual nature of biological information. So, for example, if we've been talking about DNA, take a gene, what is a gene? Well, it's a gene is a set of instructions for ribosome to make

a protein, for example. But you can't tell by looking at a particular sequence of DNA, whether it's instructional information or just junk. You just shuffled the bits. You couldn't tell. It's only in the context of the system as a whole that you can tell that that information is instructional, that it is functional. And so we can't, you see, this is what I said earlier,

the scales, you can't decompose it in the same way that we like to in physics. It's a systemic property. So we need information which is potent only in the context of the system as a whole. And there has to be a molecular milieu that can interpret those instructions and act on it. So we're into this sort of dodgy area like semantic information and meaning and so on, that the instructions in DNA have to mean something to the organism. Philosophers jump on you to say, well, you can't use terms like meaning.

and so you sort of slide around with the terminology. But there's no getting away from it that we're dealing in living systems with not just Shannon bits, but with something that goes beyond that we have not yet properly captured, I don't think. Yeah. And, of course, that does evoke concepts of creation and the ultimate teleological entity and all knowing omnipresent, omniscient, nipotent, creator. and I do want to pivot there to questions of theology. You've been on unbelievable and you've had debates with believers and non-believers.

I want to ask you, because it's not exactly clear. It's sort of a little bit ambiguous or has been to me. Where do you come down? I mean, is that a proper question, first of all? I've heard people like, you know, Jordan Peterson and others say things like, you know, how can you say believe in God, you know? And it's better to say, does God believe in me? Is that even a meaningful question, first of all, for me to even ask you?

Well, I'm asked that all the time. And my answer is, well, I'm not a conventionally religious person. That's number one. And number two is that as a scientist, I don't have to say, well, this is the way it is, and I'm not going to change my mind. And so I'm interested in the issues and the concept that you can't work in areas like cosmology, where you ask questions like what happened before the Big Bang, what is the nature of time

and then you go to quantum physics, what's the nature of reality, and then you go to life, what is life, and then what is consciousness, you know, all those things, which I love to think about. You can't think about those without coming up against those same age-old questions

of centuries were part of religion. And so I naturally find myself talking to those people. They seem interested in what I have to say. But my advice is always this, for anyone listening to these words, that in my view, it's perfectly okay to be a scientist and think, well, what does my scientific work suggest about, and I've got to use the dreaded M word again, meaning or purpose in the universe,

see if anything, you know, because it's just there is or there isn't, that you can arrive at a conclusion, while there's something going on, as I prefer to say, there is a rational scheme of things that science is busy, unraveling that the universe is not just hodgepodge of odds and ends. It is a coherent scheme that we can come to understand, and I think that's deeply significant. So through your science, you can arrive at a position, and if that happens to concur with some particular religious point of view, well, then that's of some interest. But what you absolutely don't do is decide in advance

what you want to believe. I think there's a god that did this and that, and shoehorn the same. scientific facts to fit. And I'm afraid there's far too many people in that latter category. They've already made up their minds that they believe in a particular type of God. And the worst example is, of course, the so-called God of the Gap. So if somebody's convinced that there is a God and God created life, and they'll turn around and they say, well, you scientists can't explain the origin of life, so therefore we need God. I mean, that's an appalling line of reasoning. So, first of all, I haven't really got a fixed position. on these things. Secondly, I'm not conventionally religious. I don't go to church or anything

of that sort. But I like to talk to theologians. Some of them are very smart. You see, some, if you think back like 500 years, the greatest intellectuals were actually, you know, theologians and mathematicians. And these people dealt with these really tough topics, like if there is a god, is God within time or outside of time. time and can something come from nothing and why does mathematics work and how you know they've thought very carefully about those things and i have found found that you know entertaining and sometimes productive to revisit some of those old arguments i'm particularly interested in one that theologians don't want to talk about anymore um which is the concept of a necessary being you know

we're we're all engaged in trying to explain the universe and then religious people say well it's all goes down to God and then you say, well, how do you explain God? Well, God doesn't need an explanation. Well, that's no good. But then they turn it around and say, well, what do you think? And I think, well, the laws of physics seem to do a nice job. Well, where do they come from? What's the origin of those? And I say, oh, well, most scientists don't like asking their question. They just sort of accept it as given. And they say, well, point made. You know, we both have what I sometimes call a levitating super turtle that holds the tower of turtles up. And the question is whether you call it God, laws of physics, or something else we haven't invented yet, is it the case that we could

be sure of something absolutely that there is something that would form the bedrock on which the rest of our explanatory scheme would rest? And the concept of a necessary being came out of monotheism as a notion that God's non-existence would be logically impossible. That that is, a necessary being is a being that cannot not exist. And is it possible to make that argument? And people try to do that. And so say very few theologians these days will want to dabble around in that. They regard it as a, you know, not proper subject for theology.

But I think it's, you know, really important whether it's science or theology or any ultimate explanations, is it going to be an infinite regress, an infinite tower of turtles? or can we somehow come up with a conceptual scheme that gives us great confidence for that we can build upon? Now, this necessary being, if such a thing is coherent concept, doesn't necessarily bear any relation at all to traditional gods. And I don't really have very much time for traditional notions of deities. It doesn't appear to me very much.

But I do think the way I prefer to put it is that that the existence of a universe that self-complexifies that brings forth life and brings forth beings like ourselves who can not only observe the universe but comprehend it in some deep mathematical sense I think is tremendously significant and so I think we are, there is a scheme of things

and we humble human beings are not the pinnacle of creation or anything But we're embedded in this scheme of things in a manner that our science manifests that embedding. It's through, for me, through science and mathematics that I feel I'm part of this bigger scheme. It's a long way from traditional religion, but then I think we need to get away from traditional religion. You need to go beyond traditional religion. It's fine if it gives people comfort and fulfills a social function. But it's an explanation for the physical world where its world passes used by date.

So that's really my position. I'm expressing it pretty bluntly, but that's the way I feel. No, I think that's wonderful. And actually that you are willing to grapple with it is in concert with the greatest, you know, minds of history, including, you know, Paul Dirac and Stephen Hawking, both of whose gravestones you show rather macab in this Halloween season, you show both of their tombstones. Yeah, I was waiting for Boltzman's tombstone to make an appearance. But Dirac, of course, said God is a mathematician of a very high order.

and he used advanced mathematics in constructing the universe. Albert Einstein once remarked, What interests me is whether God had any choice in the creation of the world? And Stephen Hawking said, if we do discover a theory of everything, it would be the ultimate triumph of human reason. For then, we would truly know the mind of God, the God equation. Of course, at least one of those, you know, is essentially a militant or at least a self-declared atheist, Stephen Hawking, of course,

as ambiguous whether or not Albert Einstein and Paul Dirac were actually, you know, theologically inclined. But this brings us to the final topic, which has to do before we get into my patented existential questions, which I will remind folks that you need to subscribe to my mailing list to get the answers to Paul's responses to my thrilling three existential questions that I'll be asking in just a minute. But before we get there, I want to ask if your thoughts in the multiverse have evolved. and you famously said, invoking an infinity of unseen universes, in other words, the multiverse,

to explain the unusual features of the one we do see is just as ad hoc is invoking an unseen creator. The multiverse theory may be dressed up in scientific language, but in essence, it requires the same leap of faith. And I use that in a Prager University video that I shared with you once. But I want to ask you, those, you know, hawking and clearly was not literally taking seriously the notion of God's existence. and the mind of God. It's ambiguous. Again, Leonard Mladenau was on the podcast last year and said, you know, that was basically to not turn off, you know, 90% of the possible readership who do believe in God and his ex-wife, et cetera, et cetera. Einstein, as I said, was, you know, said as many kind of atheistic allied statements as pro-theistic statements, if you will. And Dirac, as I said, never once really mentioned it besides God in that one sentence about mathematics. Are you using Creator here, are using God here and the notion of God as a, as sort of a bromide or to chastise the kind of approach of modern physicists, including your former colleague there, Lawrence Krause, who is on the show not too long ago, you know, that they invoke this multiverse and it's tantamount to God without you obviously believing and ascribing in a specific instantiation of God?

In other words, is this more of a commentary on physicist willingness to accept potentially unfalsifiable notions, or is it something else? And have your feelings evolved since that article in the Times a couple of maybe 10 years ago? I don't think my feelings have evolved. I do believe that to be a scientist, you have to have, accept as an act of faith. I mean, you've got to believe that the universe is ordered in a rational manner. And the furthermore, it's intelligible, at least in part to us, because it would be a fruitless exercise. It was all too baffling.

You wouldn't bother to do it. And so that's the sort of founding faith that you need to start doing science. So the question is, is that somehow, you know, just as bad, if you like, or just as much a leap of faith as people who say, well, I believe in a rational God who created it all? And, of course, as I indicated earlier, I'm interested in those sorts of concepts. And as a matter of fact, I have come up with a research project, and if anyone listening to this is interested in doing this, then there may even be a source of funding. And it's the following.

People bandy these words around, like, my Tower of Turtles, is better than your Tower of Turtles because it's simpler, that sort of thing. And there's a famous argument that Richard Dawkins had with Richard Swinburne, the Theologian, that what's the point of invoking a God to explain the universe?

We might just as well accept the universe. And Swinburne's answer was it simpler to accept an omnipotent God who then created the universe as a simpler explanation to which Richard replied, if I remember correctly, well, the creative

have to be at least as complex as the system it created. And so words like simplicity and complexity get banded around. And the question is, what is a simple explanation? And we're back to Occam's Razor. Well, there's a whole branch of mathematics called algorithmic information theory, which in part was invented to quantify the simplicity or the complexity of the explanations of the world. And if you believe in Occam's Razor, then you would believe that we should opt for the one that is simplest. And so the simplicity argument is a good one. If you think, oh, yes, a single super being

is a simpler thing to believe in than an infinity of universe, most of which are unseen, then you can make that argument. But the point is, we can actually quantify this. You could take, in principle anyway, you could take your favorite model of God, you know, this God has following properties. You could quantify. You could work out the algorithmic complexity of this God.

and then you can put that alongside, this is my favorite multiverse model, and compare it with the algorithmic complexity of that. And I bet you that mostly they come out about the same, that in other words, there's an awful lot of things you have to sort of take on board. And I don't think, at the moment, we've got the right conceptual framework for being able to say, ah, this explains all of existence because this is so obviously simple in a measurable way, much simpler than the other. So I think it's an open question that could be literally investigated at a quantitative way as to, you know, who, which is the greater leap of faith?

An unseen, uncreated, uncaused agent with the power to create a universe or an infinite number of universes. There's both an awful lot of information that has to go into that. So that interests me. And I'm open. I often say two cheers for the multiverse, because the reason it's so appealing to so many of my colleagues is it explains the weird bio-friendliness of the universe. It does look like, often called the anthropic principle. It looks like the universe is rigged in favor of life.

There are many examples. I won't go through them. But the feeling is, well, this looks too much like design. But if you have an infinite number of universes, then some of them will get it right. and it's a selection effect. The only one, it's no surprise we live in a universe that's bio-friendly because we couldn't live in one that's sterile. And so it sort of gets around that, which is better, in my view,

than just saying, well, God did it. So I say two cheers to the multiverse, but then people go on and say, well, that's all you need. That explains all of existence. Of course, it doesn't, because when you've got a multiverse, it needs its own laws, and usually the laws are, involve quantum mechanics and gravitation and all those things in the multiverse, where they come from? So you're really pushing the problem up a level.

So it's sort of an improvement on just sort of declaring there was a god that's one universe. But I think it's a mirage to suppose it's explained everything. Right. As an explanatory feature to explain what we do observe to actually posit that we have to wait, you know, perhaps billions of years for our universe to eat another universe, as you depict on the cover and the famous cold spot and the axis of evil and all sorts of other anomalies that we've been discussing and we could go on for hours and hours more, but I want to be respectful of your time and you've been so gracious. I would like to wrap up with the thrilling three

questions that I ask all my beloved guests who come on the show. And two of these, involve your future, one, your immediate future, or perhaps not immediate, but at age 120. And then the next one goes out of billionaires, and then we're going to go and actually go back to your past. So I'm going to start, if you will, with a question that I ask, which has to do with what form of wisdom, what value system, what articulation would you like to provide for future generations, biological and ideological, if you will, as an inheritance, a sort of ethical will that would be coming into effect when you reach the biblical age of 120, hopefully, in many, many years from now.

So, Paul, what ethical or wisdom teaching, not material inheritance would you leave, but what ethical or wisdom advice would you leave as an inheritance to the millions of people who look up to you for wisdom and advice? Well, I'm going to say something which doesn't seem very profound, but it's actually very important. And I think we all learned it during the pandemic that we have to be nice to one another. And through my life, I was born just after World War II and the horrors of Nazi Germany and then the horrors of the Soviet Union. And in China, the great leap forward. the great leap forward and it's greatly backward and all of those things.

And then, you know, for a decade or two, it looked like the world really was moving into the sunny uplands and that we were, that democracy was spreading and that, I was impressed by Stephen Pinker's book that, you know, we're actually getting less violent, less wars and all the rest of it. And now just in the last few years, it all seems to be going backwards. And I really, and this homicides,

We've got to be nice to one another. It served us very well. So my wife and I found ourselves in a somewhat happy situation. We were in Sydney. We went for a week for spring break and we stayed a year because of the lockdown and the travel ban. And there was so little COVID in Australia, it was a good place to be. But, you know, if ever we would squabble about something, you know, who's going to wash the dishes, I would always say, you know, we're in a lockdown.

to be nice to one another. That's really important. And, you know, a lot of what has happened, I just heard about it today, a lot of domestic violence that has come during the pandemic and so on, stems from the fact that people have forgotten how important it is that if you're living together with someone and it applies in households, it applies in countries, it applies globally, you really have to go out of your way to be nice to the other side. And when we see the sort of, you know, the saber rattling and the tit for tat violence and all of these things. It's such a basic human instinct. You may not agree with somebody else.

You may have grievances against them. But at the end of the day, you know, we're on one planet and we have to learn to live together. Now, you touched upon another topic, which is, I think, about a lot. and we actually have a meeting coming up at Arizona State University on this very topic, which is that in the age of AI, we're going to try to embed human values into our artificial intelligent descendants. And it's a real problem that how we embed those human values in perpetuity, because these AIs will be generating, designing the next generation of AIs and the next generation and making them, is there any way we can enshrine fundamental principles of decency that will perpetuate indefinitely?

I don't know how to do that. Asimov's famous laws of robotics, you know, we're at an attempt to state that. But how do we actually do that, or will these AIs develop their own system of values that could be very different from ours? So talking about the age of 120, I think we're already going to, we're hitting that problem now. If I were to lift to 120, I think it would become a really major issue. Now, I'm not sure how wise that is. It's sort of common sense, isn't it, really, rather than anything terribly profound about human nature, which is obviously deeply flawed. The other point I would like to make in answer to that, it's to echo E.O. Wilson, you said that we have paleolithic emotions and we have medieval institutions and we have 21st century technology. That's a dangerous mix.

We can't change our human nature much. Technology will be what it will be. We can't change our institutions. It seems to me they're not well suited for many of the problems we confront. And so we used to look up to things like, you know, the United Nations or elected governments or the World Health Organization or, you know, the large banks that were sort of oiling the wheels of the system. We've lost faith in a lot of those institutions and the church. You know, it's been very solid by sexual abuse and celebrities seem to always be, you know, We can't really look up to celebrities, whether sports celebrities or film stars anymore because they seem to always be getting themselves into trouble. You know, what are the institutions that we can build that can cope with this next challenge?

We need new ideas and we need them now. Yeah, I agree. And science used to fill that role and it's dismaying to see science become politicized and used and used and as a cudgel to, force certain aspects of state-sponsored agendas, but for good and for bad, that has been a little dismaying because it used to be science was apolitical. I always say I love astronomy because there are no, you know, democratic comets and Republican asteroids or things like that. But, you know, nowadays, there is an undergirding of politics and almost everything.

And that leads to polarization, not of the CMB type that I like, but, um, but. of the political type. Next question takes us a little further into the future. And you may remember fellow countryman, Sir Arthur C. Clark and his movie, or his book The Sentinel, that became the movie 2001, a Space Odyssey, where these monoliths, and they're floating around in space sometimes, and first they're encountered

on the plains of the African Savannah. And we're not really sure what they are. Maybe they're time capsules, maybe they're not. And I wanted to ask you, if you had a time capsule, a monolith that would last for a billion years, and lurking in our solar system, perhaps. What would you put on it or in it that would encapsulate not just your career, but the pinnacle of what human beings have achieved, not unlike Richard Feynman's famous cataclysm question? So what would you put on a billion-year lasting time capsule

to kind of swagger and show the great heights that humanity has achieved? Well, it's no surprise that I would pick something from the world of theoretical physics, because that's what I think is such an achievement, not just because we're good at it and we've explained so many things, but because he does touch on what we were talking about earlier, that is there something like meaning or purpose in the universe, and I said, well, that there is a coherent rational scheme of things that we tap into.

Another way I like to put it is that there's like a cosmic code or a hidden and encrypted subtext in nature, which we call the mathematical laws of physics, which you have to work hard to uncover. So I think that our enterprise in uncovering that deeper layer of reality is what is finest about humanity. Now, of course, some people will object and they'll say, but great works of music or art, surely are more significant,

and I'm not decrying those. It's just that if we're leaving a time capsule for an alien mind, the question is, what would it mean? It always seemed to me that if we had to communicate with the aliens, there'd been no point in sending them the latest football scores or the outcome of somebody or other's election or anything like that. It would mean nothing and be of no interest anyway. But if we were to send the fine structure constant in binary, they would know we detained a certain level of understanding of quantum mechanics and electromagnetism and so on. So it would convey an awful lot. So it depends where this time capsule is supposed to represent the finest achievements of humanity,

which would mean nothing to an alien mind, or whether we're trying to really communicate, look, we got this far. This is something you can surely understand. And that's where we got to. Very nice. And the final question and the troika of questions has to do with the far distant past, if you will. And that harkens back to our namesake, Arthur C. Clark's famous third law, that the only way to discover the limits of the possible is to venture beyond them into the impossible. So I want to ask you, Paul, what advice would you give to your former self, a 20-year-old Paul, etc?

What would you give advice-wise to give him the courage to go as you've gone into the impossible? more. That's an excellent question. And I often think about this. I often, in my mind, you know, send a little message back in time to that, you know, poor, bewildered, you know, frightened child trying to make sense of the world. The world is frightening to a child. And when I embarked on a scientific career was a huge risk. My family, I was the first in our family, even the extended family, aunts and uncles and so on, ever to go to university. So that in itself was a big departure. But becoming a scientist, a physicist, you know, I don't think there was anyone in my family knew what physics was. And so really this was a very lonely venture. And I thought,

well, is this foolhardy? Am I going into something that would lead nowhere? And, and My parents are very anxious that I should, you know, quit the university and go work for a large company that will provide me with a decent pension. And for them, stability was the important thing. The idea that you would – my father worked in the same job for 40 years. The idea that you'd switch jobs, switch careers, switch countries, you know, was completely outside their experience. And so I was doing something which looked a bit scary. which didn't have a lot of support, a lot of encouragement. And I suppose I would say to my young self, well, be adventurous, be bold.

Because there were a few times when I thought, well, this is going to lead nowhere, but I didn't know what else to do. And so I sort of hung in there, and by good luck, we talked about it, good fortune. I picked the right topics. I picked the right places to work, the right colleagues, and I soldiered on. but it was a worrying I think all young people I mean it's not just when you're a child

at the university is scary but people embarking on their early career you know do PhD postdoc that sort of phase will they ever settle down or can they buy a house have a family those sorts of things very daunting and so to my younger self I would say

well don't be too you know just stick to your guns it'll all come right in the end but of course for many of my colleagues it didn't come right in the end they quit and they went into other fields, but I think they've all done very well. Tim Bunch, we're just talking about Tim earlier, the Bunch Davies vacuum. And Tim, after his PhD, I think he did one postdoc, and then he left the field and went into the financial services sector.

I've lost touch with him these days. I'm sure he's made a good career. It's creating virtual money out of the vacuum. I'll hope he sends you a bunch of money, Paul, because you deserve it. It's been such an honor talking with you, as it always is, that you're so gracious all the time as we get together. You are a cosmic mensch. If the multiverse exists, I only hope it does. So there'll be plenty of you to go around.

Paul Davies, congratulations on this phenomenal book, What's Eating the Universe and other cosmic questions? A delightful, delicious treat for the mind and soul, I should say, as well. Paul, thank you so much for joining us and Into the Impossible. Well, Brian, thank you and for your huge interest and support for my endeavors. Any sufficiently advanced technology is indistinguishable from magic. Hey, y'all, just a simple request before you head out to the rest of your day or night. And that's to sign up for my Monday Magic messages. These are simple, sweet, short conversations that I want to have with you.

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