Into the Impossible With Brian Keating - How Black Holes Break Reality | Marcus Chown [Ep. 493]

Episode Date: May 19, 2025

Please join my mailing list here 👉 https://briankeating.com/list to win a meteorite 💥 Could a black hole erase your past? Wipe out every memory, every detail, that makes you who you are? That’s just one of the crazy questions we explore as we encounter the insane paradoxes of black holes.  Black holes don’t just trap matter. They trap information too. This is what makes them one of the greatest mysteries of our universe. They challenge our fundamental understanding of physics and our reality. Everything we know about our world breaks down when we confront their mystifying properties. Today's guest, Marcus Chown, has spent years tracing the history of black holes—not just the science, but also the brilliant scientists who gave us the knowledge and insight into these marvels. From equations scribbled in the trenches of WWI to a vanishing dark star in the 1970s, Marcus takes us on a journey from discovery to understanding…of all that we know so far. His latest book, A Crack in Everything, tells the astonishing story of how black holes went from absurd fantasy to perhaps the fundamental phenomenon that shapes our entire reality. — Key Takeaways:  00:00:00 Intro 00:01:09 The most terrifying object in the universe 00:03:05 Judging a book by its cover  00:05:10 Paradoxes and information in black holes  00:10:26 Historical figures and black holes 00:23:23 The future of black hole research  00:34:44 Are black holes responsible for our existence? 00:38:53 Do black holes create universes?  00:44:06 Human stories that didn’t make it into the book  00:59:37 Outro — Additional resources:  ➡️ Learn more about Marcus Chown:  📚 A Crack in Everything: https://a.co/d/5KI9iZK ➡️ Follow me on your fav platforms: ✖️ Twitter:⁠⁠⁠ ⁠⁠⁠⁠⁠⁠https://twitter.com/DrBrianKeating⁠⁠⁠  🔔 YouTube:⁠⁠⁠ https://www.youtube.com/DrBrianKeating?sub_confirmation=1⁠⁠⁠  📝 Join my mailing list:⁠⁠⁠ ⁠⁠⁠⁠⁠⁠https://briankeating.com/list⁠⁠⁠  ✍️ Check out my blog:⁠⁠⁠ ⁠⁠⁠⁠⁠⁠https://briankeating.com/cosmic-musings/⁠⁠⁠  🎙️ Follow my podcast:⁠⁠⁠ ⁠⁠⁠⁠⁠⁠https://briankeating.com/podcast⁠⁠⁠  — Into the Impossible with Brian Keating is a podcast dedicated to all those who want to explore the universe within and beyond the known. Make sure to follow so you never miss an episode! Learn more about your ad choices. Visit megaphone.fm/adchoices

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Fit for your ambition, First Citizens Bank. Could a black hole erase your past? Wipe out every memory, every detail that makes you who you are? That's just one of the crazy questions we explore as we encounter the insane paradoxes of black holes. Black holes don't just trap matter. They trap information too. This is what makes them one of the greatest mysteries of our universe. They challenge our fundamental understanding of physics and of reality.

Everything we know about our world breaks down when we confront their mystifying properties. Today's guest, Marcus Chown, has spent years tracing the history of black holes, not just the science, but also the brilliant scientists who gave us the knowledge and insight into these marvelous behemoths of space and time. From equations scribbled in the trenches of World War I, to a vanishing dark star in the 1970s, Marcus takes us on a journey from discovery to understanding of all that we know so far

and what we do not yet know. His latest book, A Crack in Everything, tells the astonishing story of how Blackholes went from absurd fantasy to perhaps the most fundamental phenomena that shapes our entire reality. Let's go. Marcus, soon I want to ask you

if Blackholes are actually creators, a type of force that acts as a womb, perhaps for new universes, but certainly for solar systems like our own. But first, let's start where everyone starts, as black holes as destroyers of worlds. What makes black holes the most terrifying objects in the cosmos? Well, the regions of space where gravity is so strong

that nothing not even light can escape. So they do have its reputation for sucking in material relentlessly. And this was really a big mistake that physicists and astronomers, one was made over the last century because they thought that they just suck in material. They're black against the black of space and they'd be actually impossible to see. But actually, one of the most striking features, well, first of all, black holes, the black holes that we know of in the universe include some of the most luminous objects in

creation, so they're far from being black. And although we can just about see material disappearing down the whole of a black hole just about, the most striking feature is often of material coming out. along the Titanic jets of material which stab out through galaxies for millions of light years. So really, you know, the idea of them sucking in material is kind of, they do, but actually they kind of defy that picture. And that's basically because they're embedded in the environment. And physicists and astronomers assume that they would be black because they would be isolated.

But in fact, pretty much everything in the universe is embedded in an environment. most stars are binary stars. You know, a sun is quite unusual being a solitary star, it's quite unusual. And being embedded in an environment, having a companion, having gas or dust around you, makes all the difference. And this leads to these objects being, in fact, incredibly luminous, even though they're black holes. One thing I really loved about your writing, I always love your writing, but about the book is that you kind of steer away from the kind of pop culture, mythology, of spaghettification. Yes, you mention it. Of course, you have to. It's a law of nature, right? But you really get into the hard facts and physics of it, and it's no surprise because of your scientific training and your past books as well. And speaking of books, I like to do what you're never supposed to do on the show, which is a feature called judging books by their cover. So I actually bought the audiobook and rated it with an asterism of five stars. Nothing less would suffice. It's got the encomium that it well deserves from Richard Dawkins, a pretty wonderful book. And from from my, one of my kids' favorite astrophysicist, also named Brian, Brian May.

He says, Marcus, Chon Rocks. Wow, you can't ask for her better. So please, that's the back cover. But judge the front cover, title, subtitle, and this mysterious, monstrous cover art that's so beautiful. Glad you like it. But I should point out that there are two types of black holes. There are theoretical black holes, which you talk about, which are fantastically important because, you know, major theories of physics collide in black holes, our theory of the microscopic world, quantum theory, a theory of big things, general relativity, and thermodynamics have a theory of heat.

They clash and they're not melded. They predict different things in the same domain, which is gold dust for physicists, because when a theory is shown to break down and Einstein's theory of rabbiting breaks down in the center of a black hole, then we are encouraged to look for a deeper, better theory. So there's

theoretical black holes and of course Stephen Hawking's name is associated with those and then there's the real black holes which are the black holes we've actually found out in the universe and my book is essentially about the real black holes because incredibly not only do they exist

but they're relatively common and as you said in your intro they play a role in us having this conversation today. I need to really understand the nature of black holes. Are they really you know, cosmic safes, hiding away information forever? Are they cosmic shredders, obliterating it beyond recovery? How do you, as a, you know, as a popularizer and an expletor,

exceptional expletor par excellence, how do you think of these things? How do you think of their paradoxical nature and hawking radiation, information paradox, firewalls? Talk about how these objects are fascinating in their own right, but made even more so by the many paradoxes that they bring They are paradoxical. As I said, the real black holes in the universe are paradoxical because they aren't black. They are fantastically luminous because of the material that falls into them and the friction because it turns out that everything in the universe is rotating, the earth is rotating, the galaxy is rotating, which means material doesn't fall directly into a black hole. It kind of swirls down onto it like water down the plug hole and friction cause it, was

it the heat to millions of degrees? And this is what causes them. to shine. But I ought to just point out that black holes are the simplest objects in the whole of physics because there's nothing, they're made of nothing more than space and time. As far as we know, so I want to tell you that stellar mass black holes form when a star gets to the end of its life, runs out of fuel with no fuel to burn, to generate heat, to push outwards, gravity crushes the star. And as far as we know it crushes it down to a point, what we'll be. call a singularity. And really the star, as far as we know, actually vanishes. And all that's left is a bottomless pit in the fabric of space time. This is Einstein's picture. Einstein realized that

gravity was actually the curvature of space time. And we can't visualize it because it's a four-dimensional thing. That's why it took genius of Einstein to realize. So, you know, all there is left after the star has collapsed is this bottomless pit into, from which nothing, not even like, can actually climb out. But you talked about Hawking radiation. You know, a lot of people get puzzled by this. Hawking in 1974 realized that actually black holes

glow. They have a temperature. They're of thermodynamic objects and they glow with this stuff called hawking radiation. It streams outwards. And people are often puzzled because they say, well, surely black holes are defined by nothing ever getting out of them.

Well, a hawking radiation doesn't get out of them. It's created in the vacuum just outside the perimeter of the black hole. So we define as kind of spherical membrane. This is an imaginary membrane called the event horizon, and it's the point of no return for in-falling light and matter, and the hawking radiation is generated on the outside. But I mean, I know the question you're askingly, and that is that as far as we know in physics, information is not, is never destroyed. This is quite fundamental to our laws of physics. And so the question then is, if the star, the massive star shrinks down to nothing and vanishes, leaving only a kind of bottomless pit in space time,

what happens to the information that described the star? Tremendous amount of information will be required to, you know, tell you the type of atoms, their location, where their electrons are. You know, you can imagine this is an incredible amount of information. The actual event horizon is not a perfect sphere, that it's probably got a microstructure. So if you were to zoom in on it on a very small scale, you would see it's kind of mountainous. And this actually impresses itself on the hawking radiation. You know, just as your voice, or if you're on the radio,

impresses itself on the carrier wave, the radio wave that transmits your voice to the listener. This kind of microscopic terrain actually impresses itself on the hawking radiation. And it's in this microscopic terrain that the information that describe the original star is recorded. So that's kind of one possible way. I think that's probably the consensus. You know you're an after physicist, Brian, you must know.

There's so much to unpack in this lovely book. I recommend the audio version because I always like to hear the author's voice. You didn't record the audiobook, but it's close enough to an American's ear that it sounds like you, Marcus, I have to say. It's wonderfully done. And the printed book is as well. I've actually recorded audiobooks before. So I didn't get asked on it.

Well, I really, really enjoyed it. I mean, have you done it? I bet you have. Yeah, I did it. Well, I did it for seven or eight hours of the dialogue between Galileo's World Systems with my friend Carlo Revelli and others. So, yeah, we did it. We actually recorded the first ever audiobook of Galileo.

The last one I recorded, it was two days in a recording studio. And then the third day, we had one hour left. And when I got in a recording studio, they said, oh, yesterday, when I'd recorded eight hours, we had an unexplained hiss in the background, and could you record it again? And I mean, I was in the studio for 10 hours and I was kind of speechless at the end. Because I thought it was all over. But obviously, there were harder jobs like working down coal mines than reporting your audio book. It's peak pollination season, and my business is scaling fast.

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during times of high network usage. Writing equations in the trenches of World War I. And soon I want to ask you what the next great black hole discovery might be, whether it would be in theory, observation, experiment, ranging from quantum gravity breakthroughs to so-called multi-messinger astronomy and observations that we haven't dreamed of yet. But first, to really understand where we're going,

we have to look at how we got to our understanding of blockholes from the first place because it's a human story, too, not just about cosmic monsters and ruptures in space time. And it involves people like Carl Schwarzschild and Subramonian, Janja Secar, and many, many others.

And I wonder, of all these, these, you know, kind of characters that you got to study, which is the most sympathetic or pathetic, perhaps. There's a lot of sadness. There's a lot of debauchery or, shall I say, you know, kind of skullduggery by some unsavory characters that goes along with it, including the ignorance of underrepresented groups and astronomy to get attention. So talk about the history of the discovery, the theoretical predictions, and the experimental triumphs that led us to the understanding that we have now before we pave paths or to the future. So the book begins with Carl Schwarzschild, who was on the outbreak of the, it was German,

he was the director of the Berlin Observatory on the outbreak of the First World War. He joined the German army immediately. He had no need to. He was 40 years old, but anti-Semitism was on a rise in Germany, and he was Jewish. And he wanted to show he could be a patriotic German. He ended up running a weather station in Belgium, Calcutt and Shelter Straitatories. He ended up at a place called Mulhouse, which was on the northern border of France, between France and Germany. The only bit of the Western Front was mountainous.

And in November 1915, he went on leave to see his family in Berlin. And on the 18th of November, 1915, he attended a lecture by Albert Einstein. And Einstein, in four lectures in November 1915, presented this revolutionary news theory of gravity. And George D. Charles was completely captivated. He went back to the front, and he did something that Einstein thought was impossible. And so what you have to realize is that Einstein had shown, you know, Newton said there was a gravity was effectively an invisible tether that connected the Earth and the Sun and kept the Earth orbiting forever. Einstein realized this was incorrect. What gravity, what a mass like

the Sun actually does, is it kind of warps the space time around it into a valley. I said before you can't actually see that valley. And the Earth kind of goes around the, the, the Earth kind of goes around the upper reaches of that value, rather like a roulette ball in a roulette wheel. So gravity is actually the curvature of space. Now that one thing you need to know is that Newton used one formula to characterize gravity and Einstein used 10. So actually finding a curvature of space for any useful body, like a star, was considered by Einstein to be impossible. But within about a couple of weeks, Schwartzschild, on the Western Front, found the solution, sent it to Einstein. Einstein was amazed to get a letter from the Western Front,

and then to find there was something in it that he considered to be impossible, you know, and he presented this result at a Prussian Academy of Sciences. But Schwartzrader not finished and realized that if the, basically he found the curvature, sorry, around a spherical mass, which was the shape of the valley of space time. And then he realized that if that mass were to become more, more compressed, the valley would become steeper, until eventually it became a bottomless pit from which light could not escape.

and therefore the object will be shut off from the university, it would be black. He sent this to Einstein. Einstein presented it again at the Prussian Academy, never believed in black holes until he died. And there's an obvious reason for that. It taken 10 years of blood and sweat to come up with his new theory and to discover within a few weeks of presenting it,

that there was actually a place where it broke down. I told you before that if a star shrinks, there's nothing to stop it shrinking down to a point. We call it a singularity, when everything skyrockets to infinity, the density or whatever, when you get that in a formula, when you get that in a theory, it tells you your theory has been stretched to a point beyond which is it's got anything sensible to say. So, Schwarzeneghner, and then sadly, you know the story, sadly had a disease called Penficus Vulgaris in late December.

In 1915, when he was writing to Einstein, he got these bisters in his mouth. They spread all over his body, took a long time for him to be. diagnosed, but this is a disease in which the immune system attacks the skin. And the skin, of course, is your barrier against infection, against microorganisms. So he knew he was going to die, and he actually went back to Berlin and died in May 1915. But his idea did not die with him. And I just, there's a lot of things I could tell you, but you asked me about people who I would like to talk about. And one of them is Louise Webster, who has been entirely written out the history of science. She was the current discoverer of Blackholes with Paul Murdin in 1971. And of course,

if you've read my book, you've read my book, of course. I was switched on to Black Holes at the age of 12 because I was a member of the Junior Astronomical Society and my dad took me to a talk in London by someone called Paul Murdin, who hobbled towards the stage on crutches. He had childhood polio and he priscilla to talk about this object called Cynus X-1 which was the first black hole candidate and it blew my

mind, it blew my 12 more old mind you know so but it's only recently I discovered that he actually co-discovered it with a woman called Louise Webster they were both 30 years old she was Australian and she went back to Australia and she had liver disease and she had one of the very first

successful liver transplants in Australia but sadly got dancer and she died at 49 and she's been completely forgotten. So if you remember anything about this podcast today, remember the name of the co-discover of black holes, Louise Webster. And I think you also know that pulsars or neutron stars, these are another collapse form of stars. So if a star is not massive enough to collapse all the way down to singularity, it can form what we call a neutron star,

which is a star basically about the size of, I don't know, half the size of San Diego. But with the mass of the sun and a sugar cube of material of a neutron star would weigh as much as a human race. So they're super dense objects. They were discovered by Josephine Bell, who was a graduate student at Cambridge in 1967. And there have been three Nobel Prizes, four pulsars, and none have gone to her. So the two types of stars, what we call relativistic stars, the two types of stars are endpoints of stellar evolution that require relativity to understand black holes and neutron stars were both discovered by women. I had Dame Bell Burnell on the podcast. I had her on December 10th in 2023, which you'll recognize as the day the Nobel Prizes are given away.

So I wanted to make sure that at least we celebrated the proper way. There's one other object that plays, Sort of, it might have been a red herring or it might have been kind of a false start, but is integral to the story of black holes. And that's their, you know, kind of mirror image, white dwarves, at least. The story that you weave so beautifully starts off with a young Supermonian Chandrasekar traveling and then ultimately getting undercut. And that delaying the progress of not only the discovery of black holes, but theoretical astrophysics for decades to come. He eventually did get recognition with a Nobel Prize, but not until he was quite old. So talk about him, his discoveries, why they're so important, and how they segue into the black hole narrative. Well, of course, nobody who thought about it wanted to believe in black holes.

I mean, this is the story of people over the last century being dragged, kicking and screaming, having to consider these objects, because no one wanted to think about the singularity at the center where everything breaks down. And certainly Einstein didn't want to believe it. So anyone after about 1915 who thought, which were very few people, thought there's got to be some other force that intervenes that stops a massive star, or it's the core of a massive star at the end of its life, from shrinking down to an infinitely dense point to a singularity. There's got to be something that stops it. And in the 1920s, something turned up, which was, of course, what we call quantum theory. Quantum theory is our very best description of the microscopic world of atoms and their constituents. You know, it's given us lasers, nuclear reactors, iPhones, you know, basically created the modern world.

There's a principle called the Heisenberg Uncertainty principle. And all we really need to know is that if you try and compress something like a proton or electron or whatever into a small volume, it resists. And this is not anything to do with its temperature. It's not the fact that it's flying around because it's got temperature. This is a fundamental thing. And so anyone who thought about it thought, well, actually, and there were people at Cambridge in England, like Ralph Fowler, who thought about this, well, actually, this runaway catastrophic gravitational collapse will be stopped. And then, as you say, a 19-year-old Indian from Madras, which is now Chennai, I believe, in India, was on his way into Cambridge to do a degree. and he was sitting on the deck of his ship as it went through the Suez Canal

and he was thinking about the death of stars. And he happened to know about quantum theory and he knew a bit about stars. And he realized that everyone who thought about this problem had missed out one key element. And that was Einstein's theory of relativity, which basically gives an upper limit to the speed of anything. So if you compress a star gets the effect,

end of its life and it shrinks and its electrons get pushed together. They can push back through the Heisenberg Uncertainty Principle. They push back, you know, rather like, you know, raindrops on a, on a roof, you know, spattering on a route. But there's a- Pushing New Yorkers. Yeah, there's a limit, there's a limit to how fast they can push back because they cannot move fast in the speed of light. And he realized that there was actually, if the star was more massive, what we called it, what his name was Superman and Chandrasekha. We know, I call it the Chandrasekarl limit. If a star is more than about one and a half times the mass of the sun,

this Heisenberg uncertainty principle, what we call degeneracy pressure, could not prevent the star from collapsing. So if the style, at the end of which I was more massive, a black hole would be the outcome. And as you say, probably one of the greatest astronomers of his day, Arthur Eddington,

one of the two people who had understood Einstein's theory of gravity in 1915, the other was William De Sitter, who was a Dutch physicist, but Eddington understood it and presented it to the English-speaking world. He was, I mean, I remember there was a poll, I think it was in the 20s or 30s, in America of who was the top 10 astronomers in the world,

and he was ranked by American astronomers as the number one astronomer. And Eddington just did not believe in this limit, this Chandles-Sacar limit. And it's very hard to understand why he didn't, because he just said, the world does not work this way. Nature does not work this way, which is not really much of an argument. And he did the best to completely undermine Chandraseko and, in fact, humiliated Chandraseko gave a presentation at the Royal Astronomical Society in London. And he did not know that Eddington, well, Eddington was going to go to talk after him.

And he did not know that Eddington's talk was to entirely. undermine him. And poor old Chandra Seykar had to even move to another field of of astronomy because he knew he could not compete with Eddington because Eddington was such a powerful figure. But as you just say, in 1983, he was vindicated. He got the Nobel Prize. Eddington died, I think, in the Second World War. Never got the Nobel Prize, but Chandler did. And he was very hurt all of his life, although he was always. always said that he admired Eddington. And I was there, actually, on the spot at Caltech, when Willie Fowler got the Nobel Prize in 1983, and Chandrasekhar shared the physics Nobel Prize that

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We went, as I understand the trajectory that this subject took, thanks to your book, white dwarves, then followed by neutron stars and then eventually pulsars and then black holes. And theory was always in front. And even it was in front for a long time with gravitational waves. I've spoken to, you know, all three, Kit Thorne, Barry Barish, and Ray Weiss on this podcast, as well as people like Shep Dolman from the event horizon telescopes. What do you see as the future of this marriage between theory, phenomenology, observation, instrument builders, of chasing down the impossible?

What's going to be the next frontier? Is it some new developments in theory, or have we reached the end of theory? Is it some new technological device that we don't have yet? Or is it some huge budget to build larger and larger instruments to the kind of which we do have? Where do you see the future of this field going? Well, I mean, it's incredibly exciting. So first of all, you just mentioned gravitational waves, which are like ripples in the fabric of spacetime.

I mean, basically a tsunami in the fabric of space time. But, of course, by the time we pick up these signals, they filled a huge volume of space and become massively diluted. But they were detected in on the 14th of September 2015, predicted by Einstein in 1960, because, you know, mass or energy can warp space. It can also ripple it. it can also jiggleick and knows what gravitational waves are.

The first discovery was of two black holes which had merged, and I think there were something like one was about 35 times the mass of the sun, the other one about 50, something like that. This was much, much bigger than anyone had expected. And we're now seeing mergers. We've seen about 100 now, including neutron-style mergers and black hole neutron-style mergers. And we're seeing black holes which are much more massive

than actually could. possibly exist. So there is actually a gap, a mass gap where we do not expect to see max black holes, and that is because when a star is massive enough, we get what was called a pair instability supernova, and the star blows it all completely apart. So there is no implosion at the centre to form of black holes. We shouldn't see any black holes in a particular range, yet we do see them. So what we're learning is that the black holes we're seeing merging, pairs that we're seeing merging, spiraling together and merging, individually, had actually merged before. So this process of merging is quite common. That's going to continue,

and we're going to be surprised by what we actually discover. I think probably one of the most amazing things is the James Webb Space Telescope, which is showing us the pretty newborn universe when it was maybe 2 or 3 percent its current age. And we're seeing these supermassive black holes, or we're seeing evidence of these supermassive black holes very, very large, very early on. So we're seeing billion solar mass supermassive black holes. And we're seeing billion solar, holes within, you know, three or four hundred million years of the Big Bang. And that's quite difficult to understand, but I think there's some evidence. I mean, there are these things called red dots you've probably heard about, which have been seen,

and they may well be back holes enshrouded in a very, very dense shell of material. And so sucking in material at a rate greater than they ought to be able to do. So we may get this pretty soon, I hope, the solution to where these supermassive black hole, come from. Now, I ought to just say, what I haven't told you is there's probably a complete spectrum of black holes from stellar mass up to really large ones. But we basically see two populations. One is stellar mass black holes, which we believe form when in supernovae, a star blows itself apart. Paradoxically, the core implodes. In fact, it's the implosion that drives the explosion. And then we see these supermassive black holes and the biggest ones,

are something like 60 billion times the mass of the sun. And their origin is a complete mystery. We're seeing them very, very early on in the universe. So we believe that black holes start off quite small. I mean, it could have been an early generation of stars that formed very shortly after the Big Bang. There's a lot of evidence that they would have been more massive than stars today. So it's quite possible they would have gone through their livestock stories.

Their life history is quite quickly, exploded up for produced black hole. Those black holes maybe would have merged, sucked in material. but it's quite difficult to see how a black hole could grow from stellar mass to a billion times the mass of the sun in the available time. So that's a really big mystery. I mean, it could be, and see,ably, that they are spawned in some way in the Big Bang itself,

in the turbulent conditions in the Big Bang. That would be very interesting. So I think, you know, to answer you a question, I think the origin of supermassive black holes would be, that's an incredibly important question to answer. So let's face it, There's one Hubble Space Telescope discovers in the 1990s that there's actually a supermassive black hole in the heart of pretty much every galaxy,

in fact, essentially every galaxy. So we don't know what they're doing there? Did they come first? Were there supermassive black holes formed in the universe? And then maybe they gathered material ratin which then collapsed to form stars. So were they the seeds around which galaxies form? Or were the galaxies formed first? And then maybe there were very dense clouds?

clusters in the centre that ended up forming supermassive black holes. We don't understand anything really about the origin of supermassive black holes. So the story of my book basically is how black holes will come in from the cold. So as you said in your introduction, Brian, at the very beginning, they were so ridiculous as not even be considered the preserve of science fiction. But gradually, last century, they moved more and more into the centre of science. When we realized that they had to exist because we discovered Martin Schmidt at Caltech, discovered quasars, which are often pump out a hundred times the amount of light of a normal galaxy

from a volume, maybe the size of the solar system. So that was 1963. Within a year, theorists had realized that it was only one possible source of that energy, and that was material swirling down, like water down a plug hole, you know, onto a black hole. being heated to millions of degrees and shining that way, but not a black hole of a few times the mass of the sun, a black hole of billions or tens of billions to ties to the sun. So supermassive black holes.

But then we thought, well, quasars, they are what we call active galaxies. There's a whole lot of zoo of them. But basically, they're galaxies. We define them as galaxies that generate most of their light, not from stars, but from a cretion disk, what we call around a supermassive black hole. And at that point, you know,

only 1% of galaxies were active galaxies, so we could think, well, they're not really important. We can sweep them on the carpet, they're anomalies, and then we discover there's one in every single galaxy. And the reason that we only see them in only 1% of galaxies are active is because in only 1% of galaxies are they being fed. So in 99% of the galaxies, they've sucked in all the gas and Ripsobot stars, and they're slumbering.

You know, they're slumbering. And, of course, there's a supermassive black hole. in the center of our own galaxy, although it's a tidler. That's right, compared to our big brothers in M87. I want to quote a lyric from the famous astrophysicist, not Brian May, but from Leonard Cohen. And it goes like this, ring the bells that still can ring.

Forget your perfect offering. There's a crack, a crack in everything. That's how the light gets in. And I interpreted the title of your book along those lines in that you present black holes as this confluence between all the major ideas, of physics, modern physics, quantum mechanics, thermodynamics, information theory, general relativity, special relativity,

they all sort of break down at one level or another. How important is that narrative, you know, where the cracks are what reveal the truth and why we shouldn't, as physicists, be afraid of, of flaws and cracks in our most cherished theories and ideas? Well, you've put your finger on exactly what the title means, you know, because, you know, in physics, Places where our known laws of physics break down are gold mines.

You know, they're really what we look for. You know, we look for paradoxes. We look for places where there are, certainly where there are two theories that predict in the same domain different things. Then we know that one or both of those theories is wrong. And there is a great, I saw this survey, a psychological survey, and it was about people who were willing to change their point of view. You know, it was talking about politics, but people are willing to change their point of view. and the people who scored highest the people who were most likely

to change their view were people of a scientific background and that is because they actually enjoy seeing, you know, they enjoy being proved wrong. So really scientists get a lot of joy out of finding out that their theories don't work because they're constantly looking for the deeper,

better theory and really our scientific theories are provisional, you know, they are the best description we have at this moment, but we know they break down. So, you know, to everyone but Einstein, who was not happy with black holes, black holes are of gold dust, you know. I mean, there if we get contradictions in physics, and we are challenged by nature to come up with a better theory.

And a better theory we expect, but we could be wrong, is what we call a quantum theory of gravity, where we unite our theory of the very small, which is quantum theory, with our theory, the very big, which is general relativity. Because in a black hole, something very big becomes very small. You know, a star shrinks, smaller than an atom. So we need to unite these to understand what happens in the center of a black hole.

And coincidentally, where the universe came from, because we believe that the universe also began in a singularity, although a singularity in time rather than a singularity in space, but similar kind of things. So, yeah, and I was saying about how scientists actually revel in how. having to change their mind, you know, because really, I mean, if you go back 50 years, I mean, our picture of the universe is entirely different to the portrait we have now. I mean, imagine how many objects that we know of now in the universe that we didn't know about. I'm thinking of things like gamma ray bursters, which were actually, they were known about,

but the US military was keeping them a secret, discovered them because it was trying to find the gamma rays produced by clandestine Russian nuclear tests. It was using spy satellites to do that, and it discovered this, you know, a burst of gamma rays once a day from somewhere in the sky. Fortunately, those satellites, they could tell where they were coming from. Otherwise, they would have triggered a nuclear war, and they knew that they were not coming from the Russians,

they were coming from space. Black holes are just really challenging. When you need to build up your team to handle the growing chaos at work, use Indeed-sponsored jobs. It gives your job posts, boost it needs to be seen and helps reach people with the right skills, certifications, and more. Spend less time searching and more time actually interviewing candidates who check all your boxes. Listeners of this show will get a $75-sponsored job credit at Indeed.com slash podcast.

That's Indeed.com slash podcast. Terms and conditions apply. Need a hiring hero? This is a job for Indeed sponsored jobs. Yes. Yeah, it's a unique laboratory for understanding physics at the extremes. I want to mention something you hinted that before I get to the creation of the universe from black holes, maybe we can touch upon the interesting theory that you discuss in the book, which, by the way, you don't discuss cosmic natural selection, which we're going to get to in a minute,

but you do discuss how our existence might be owed, in fact, to black holes. Can you elaborate on that for listeners that might be shocked again to hear such a wild idea? This is the greatest irony. So, you know, they start off, you know, as really not even a preserve of science fiction. and they move so far into the center of our picture that we actually think that, first of all, they play some key and mysterious role, still mysterious role in generating the universe we see around us,

but specifically in us having this conversation. It comes down to, I told you, every galaxy's got a supermassive black hole in its core, and we've got one. It's called Sagittarius A Star. It was discovered in 1974, so 51 years ago. Two people in 2020, Andrew Gettis, a astronomer in California, and Reinhard Gendez, in Germany won a Nobel Prize in 2024, working at its mass, and its mass is 4.2 million

times the mass of the sum. But this is a mystery because this is really, really tiny. This is thousands of times smaller than the supermassive black holes in active galaxies like Quasasots. And if we compare the Milky Way with Andromeda, Andromeda is the nearest big galaxy. A galaxy that's a spiral galaxy, and really, very similar to the Milky Way, its supermastic black hole is 50 times bigger. So why have we got such a tiny, tiny supermaster black hole connected to us being here? Because I said in the beginning, in the guise with big black holes, they have these tremendous

titanic jacks that stab outwards from the north and south poles of the spinning black holes, stab outwards often not many millions of light years through space, but sometimes 100 billion like this with space. I mean, it's shockingly. How they stay collimated, how they stay narrow for that long, is still the mystery. But what in the galaxies with the big submissive black holes, these jets can push away, drive away,

all the gas in the center of galaxies. Now, that's the raw material of new stars. So in these galaxies, the star formation is kind of snuffed out after one generation. But it didn't happen in our galaxy because we've got a tidler of a black hole. We've probably never had any powerful jets at all.

And so we've had multiple generations of stars, and our sun is a third generation style. And in each successive generation, which forms from the raw material, you know, of the exploding stars of the previous generation, in each successive generation, more heavy elements are forged. So more carbon, more oxygen, more iron, more calcium. That brings up this little artifact that I give away to my listeners. If you go to Brian Keene.com slash list, this is a meteorite,

which is a fragment probably of a population two star that eventually coalesced to be a part of our solar system. as a bridge between the earlier and later generations. So these stars give their lives to make our lives possible. Yeah, and now, because of our small black light hole, it has been possible for there have been multiple generations of stars. And I just listed those elements, and those elements that have been forged because we've had multiple generations, because we have a small submasible black hole,

those elements are precisely the ones needed to make your meteorite, to make a rocky planet like the Earth, and to make biological life like you and me. We could not be having this conversation in, for instance, M87. You mentioned M87. This is a nearby galaxy with a 6.5 billion solar-mast black hole image was habitized in 2019, the first ever image of a black hole. And we could not have arisen in that galaxy.

So we believe that that galaxy is probably a biological desert. It's remarkable that we've come from thinking that these objects were so ridiculous as not to be to preserve a fun fiction to thinking that we're having this conversation because of a black hole, Sagittary, or you stall. And that brings me to this provocative question that I've been teasing the listeners about since the first few seconds. We started off the conversation

with a description of black holes as predators, as paradox machines. And I promised I'd come back to this idea that the black hole might not be the end of the story when it comes to producing life on Earth. What about if it's the cause not only of our existence on this beautiful podcast, but of entire universes like our,

own within the multiverse. And just for the readers and listeners that are not familiar, rather Lee Smallland past guest on the podcast, proposed that Black Hulls might actually spawn new universes. Each one was slightly mutated laws of physics, a kind of cosmic natural selection. He calls it that, in fact, CNS. Now, I noticed in the book, I didn't see it. And that was a little bit surprising. I don't believe you mentioned Cosmic Natural. You mentioned Lee. Lee is in there, I think, one or two times. But I'm curious. First of all, why didn't you mention it? Was it a little bit of a bridge too far? Or is there actually some justification for treating these black holes, not only as fertilization within galaxies for life like us to exist, but also for universes

onto themselves to exist? In other words, within the multiverse to explain the peculiar qualities of our own. Is this a bridge too far or are black holes not tombstones, but rather cosmic universal cradles? I think it's a bridge too far. And the reason is that my book is principally about real black holes, you know, black holes that we've actually discovered. So it's the, you know, it culminates with, you mentioned the event, Horizon Telescope, getting the first ever images of Sanctuary's O Star and M87, the black holes. My last chapter is about speculative ideas, but I didn't mention this one. And one of the reasons is that we really don't know what it's like inside a black hole. So I've got the stories from people like Paul Murding, who was the co-discover of Stella,

black holes, and Roy Kerr, who was a really interesting character. He's now 91 years old. He basically came up with the first development in Einstein's Theory of Gravity for 47 years. And he did something which people thought was impossible. He discovered the shape of the space time around a spinning black hole. Now, I told you, everything in the universe is spinning. So actually, Schwartzschild had come up with the shape around a static black hole. So that wasn't very realistic. So he came up with a description which describes every single black hole in the universe. He was 29 at the time. He himself gave up on working out what the space time was like inside a black hole

because the problem was just too difficult to solve. So we really don't know what it's like inside a black hole. Not only can we not solve Einstein's equations to find out what the shape of the space time is inside a black hole, but we certainly don't know what it's like near the singularity. Because the singularity is doesn't exist, by the way. tell you that. When a singularity appears in a theory, it's totally your theory is broken, you need a better theory. So we need a quantum theory of gravity to tell us what exactly is at the centre of a black hole, and we don't know what that is. So saying that, you know, it connects

to another region of space time, that it's a time machine, it generates another black hole or another universe, this is so far removed from what we can confidently talk about that I didn't really smooth it. There's no other books about black holes. Most books about black holes are about theoretical black holes, about hawking radiation.

I love Lee Smohen's idea. I hope he's correct. But again, it's not very well-founded. And the problem is once you start admitting not very well-founded ideas into this, you have a book which is 100 times longer than the book that you were writing and people get lost.

You know, what do we know and what that we don't know? My thought is really that the things that we know are so fantastic and so amazing that we don't need to really spec anymore. Gray, you know, I mean, if you're thinking of something else like dark matter,

so with dark matter, which was this invisible stuff that fills the universe, outweighs the visible stars and galaxies by about a factor of six, we can speculate, and there's literally hundreds of speculations as to what that dark matter could be. But it doesn't really get us

anywhere, and the reader then gets confused, by all these hundreds and hundreds of possible suggestions, none of which are constrained by physics, because we've never detected any. So, yeah. Now, I think Lee Smolin wrote a wonderful book, didn't he? It was called, what was it called now? And the Life of the Cosmos.

Yeah. About black holes. Yeah. So basically, he says that the conditions necessary to create black holes, the laws of physics necessary to create black holes, are also the laws of physics necessary to create bologous. life. So the two are hand in hand. So the universes that create the most born and most black holes, I think that's correct, isn't it? Produces constants of nature and laws of physics that are

compatible. It's an anthropic, what's called a weak anthropic. Yeah. I mean, obviously, as Einstein said, the most incomprehensible thing about the universe is it's comprehensible, which is a fantastic remark, isn't it really? Own it all. Pay off your home, travel for life, drive a Ferrari, in celebration of the premiere of the Monopoly Big Board Buckslot machine by Aristocrat Gaming, Yamava Resort and Casino at San Manuel is giving one person a $1.6 million dream package. The biggest prize in Yamava's history.

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One thing I appreciated with bittersweetness was you're mentioning the bice two affair, which I played a not insignificant role in. And it made me think of some of the more, again, there's a lot of, you know, pathos in these. Our mutual friend, Jan 11, who you write about in the book, has written, you know, Black Hole Blues about the, you know, kind of stories of of the unsung heroes, the lovable losers and so forth. And one of them, you know, which I resonate with, no pun intended, actually, pun intended, it was a good pun, is Joseph Weber. So he, of course was, you know, claiming that he had detected gravitational waves, you know, three or four

decades before Igo actually did it. And it was only because of a slight amount of hubris, I think it's safe to say that on his part, that he never really gave up the belief that he had discovered these first. And let me think about all the false starts and the, and the curious characters in this book. You mentioned Louise and you mentioned Johnson Bell and others, but are there other stories, maybe that didn't fit into the book or perhaps would be in an additional book, are there other, you know, sort of human stories that were neglected, you know, because we look at the black hole and it's not unlike a black mirror. We learn about the subterfuge and the jacanery and the stolen credit and the stolen valor in this book very delightfully. Or there

other characters that you didn't get a chance to disclose that maybe the public would have a desire knowing more about. Popular science writers tend to write science as if it's like, you know, one-way street, everything, you know, it's a logical. timeline, but in fact scientists are human beings. They proposed existence of things for the wrong reasons. Progressive science is like a drunkard's walk, you know, a few steps forwards, a few backwards, you know. I mean, your subjects I know is the, is the cosmic background radiation, which is the afterglow of the big bang. My first popular science book was called Afterglow Creation, and I went to interview lots of people who, unfortunately, I did, I talk to Robert

Wilson, who discovered the microwave background, to people like Bob Dickie and Baby Wilkinson and all these kind of people. But, I mean, interestingly, I mean, one of the great, great figures was George Gamoff. He basically came up with the idea of the hot Big Bang. You know, I mean, common sense, I suppose, tells you that if the universe was smaller, it would have been hotter because if, you know, squeeze the air in a bicycle pump, it gets hotter. But no one had really thought seriously about that. So Hydrin Hubble discovered the universe was expanded in 1929,

which meant that if you ran the history of the universe back in your minds, like the movie in reverse, you would come to a point when it was all compressed into a small, suppose, I call it Big Bang. But no one really thought more about it. It was so ridiculous to think that they could think about physics then. But then we get George Gamov,

who was a Ukrainian American physicist, and he was very interested in where the chemical elements had came from. There was a lot of evidence from the early 20th century that the universe had begun with the simplest element, and all the other elements, 92 naturally occurring ones, had been assembled by these atoms or nuclei coming together. But that required a lot of heat. Turns out that the nuclear, the cores of atoms,

are positively charged. And when you try and thrust together to positively charged nuclear, that they really repel ferociously. So you really have to smash them together at very high speed, and that means high temperature. We just mentioned, by the way, Arthur Eddington, and one of the greatest, one of the greatest British astronomers,

but he had made a mistake, and he thought that, well, he had an idea that elements could not be built inside stars. By this time, they knew, by about the 1930s, that hydrogen nuclei, the cause of hydrogen atoms, if they were blew together in a multi-step process to make the second heaviest element helium, this would liberate enough energy to explain sunlight or starlight.

But he thought Eddington that as the sun rotated, there would be currents, what we call meridional currents, which would kind of spread out that helium. So if you imagine the helium is the ash. So basically this would actually cause stars to fizzle out. He had managed to rule out stars as the place where elements were built. So Damoff was thinking, where else? You know, and this is when he started thinking about the universe, when it was small, it would have been very hot, and he thought that's just it. That's the place, you know. And he got his pre-fudence in Washington, Ralph Alpha and Robert Herman, to work out the details because Gamov was not a details man. He came up with a lot of brilliant ideas in his life that he was not a details man. And they worked it all out. And they realized that, incredibly, you could actually end up with 10% of the backgrounds in the There's helium, 90% hydrogen, but you couldn't get really beyond that at all. So it turns out the 10% of the atoms in the universe are hydrogen.

So again, so he comes up with the idea of the hot big bang for entirely the wrong reason, but he's correct, you know. And then again, when people started searching for this afterglow, there was a team at Bell Labs in Holmjow in New Jersey, and there was also a team remarkably only about 20 miles away in Princeton and they had a little radio dish or radio horn on their roof.

The leader of their team was a guy called Bob Dickie and he had the idea that the universe was pulsating. You know, it was what we... Cycling. Yeah, like a cyclic universe, like a giant beating heart. So there would be a big bang, it would expand,

gravity would eventually clapped it down to a big crunch. expand a game, and you realize that this beating heart universe would have radiation over. You know, there would be something like a billion, 10 billion photons for every particle matter or so. So his team was looking for this afterglow for entirely the wrong reason, because the universe, we don't believe the universe has pulsated by that. This has happened with the discovery of planets. I mean, the first giants were found around a pulsar, weren't they?

I can't remember. Yeah, there was a planet around a pulsar. Yeah, obviously, they couldn't be, there couldn't be any life on them because a pulsar is a, super dense object with a lot of radiation around it. But this triggered people to actually look at real stars, you know, because they detected it by the wobbled the star. So the star, the pulsar, was moving backwards and forwards because it was being periodically tugged from one side and the other side by a planet.

And this got people looking at real stars. And sure enough, they began to find planets. And now we've probably got five or six thousand extra solar planets that have been found. So again, you know, there's all these accidental things that actually happen. I really love this, the way this work. One of my heroes is Fred Hoyle, who was at Caltech, but he in fact quacked the problem of where all the elements in your body come from. He found the about eight or nine processes, nuclear processes,

in stars that made all the elements. He put together some pieces of information. He was working on radar during the Second World War. He came to America. In that time, he was supposed to be. doing war work, but he went to California, he met an astronomer for Walter Bada, who was at Caltech. Bada gave him some papers on supernovae,

styles that explode. And on his way back, he got delayed in Montreal because of bad weather. And he bumped into a lot of people that he knew from Cambridge. And he knew they'd been working on a project called Tube Alloys, which was the British project to build an atomic bomb, you know. So he knew, and he gathered from reading between the lines that there was a problem.

There was a problem that they had a problem trying to build an atomic bomb, and he couldn't think what the problem could be. He knew that one of the elements that would be used was plutonium, and he realized that plutonium, as you push two bits together to get a critical mass, would generate so much heat that it would push itself apart. So the only way you can actually create the nuclear reactions of a nuclear bomb was to implode this stuff.

In Barda, Bada, it has. had realized that supernova were exploded by the implosion of stars. And he put the two ideas together and he thought, is it the implosion of a star at the end of its life that creates the billions of degrees necessary to meet the heavy elements? So the idea had come from the atomic bomb. So it's just weird the way all the ideas come together. And he was able to show in about 1946 that you could,

And we would get what's called nuclear thermodynamic equilibrium. Basically, the relative abundance of elements would freeze out and he was able to show that the relative abundance of these elements like iron and nickel and all these

was exactly what we'd observed. And so that was a piece of information which came from the atomic is just being delayed in Montreal, that bit of information that gave him, he was able to predict the relative of abundances of some elements and then he came to Caltech in 1953 and the reason he came to Caltech was because he was

at a conference in Italy on galaxies and Walter Bada had presented a result in which he realized that the distance indicators, there were two types of what we call sephi variables and we had not realized there were two types and if you realize this you realize that in fact the universe was twice as old as we had thought. And he had presented this in the paper, but there were two people in the audience who then quickly published a paper with Bada's result as if it was theirs.

And Huyle had been sitting there because they didn't have a secretary to record the result, and he was able to prove that Bada had his idea stolen. And Bada was so pleased that when he went back to Caltech, he wrote to Poyle and said,

I've persuaded people here, to have you come over, would you like to come over? He went over, he met Willie Fowler, who was a nuclear physicist, and he had a prediction. You probably know this prediction, that the problem in building up the elements is when you get helium, if you stick two helium nuclei together, you get beryllium-8 and it's not stable.

So how do you get to heavier elements? So he thought maybe, occasionally, three helium nuclear collide at the same moment. It's right, you know, in a supermarket car park, three people with their shopping trolleys all collide at the same time. And if this reaction with what is called what we call resonant, then you would get the formation of carbon and then you could build all the heavy elements.

And he went to Willie Fowler, and Willie Fowler was a nuclear physicist, and there's something that physicists will never admit to you. and that they've only ever solved one problem exactly, and that's the two-body problem. So they've only sold that problem of an electron going around a proton in a hydrogen atom, the moon going around the earth,

that's the only problem they can solve exactly. Once you get to three bodies or more, it's not possible to solve it exactly. It turns out that a nucleus of carbon has 12 particles in it, six neutrons and six protons. This is finding out anything about it, like its energy

states, was impossible. And this guy from Ingram with round spectacles turned up in Willie Fowler's lab at Caltech and he said something that no nuclear physicists, or he claimed something that no nuclear physicists would ever claim. He said it's got

an energy state at this particular level because he knew it had to in order for three helium nuclear I had to come together and make carbon 12. And there was a discussion and they realized that they had measured the properties of carbon twirl, but if it had a, they might just have missed something. Three days later, they found the carbon trial.

He's the only person to have made a prediction ahead of what you call an anthropic argument. So his only argument was, we are here, we're made of carbon, therefore this state of carbon must exist. So I mean, is the unverbalmed. The so-called oil miracle. Of course, he actually coined the term Big Bang and never believed in it. And he worked very closely with my late-grade colleagues, Jeff and Margaret Burbage. Absolutely. He was considered to be a rather difficult character and a bit of a loner,

but actually history shows that he had incredibly loyal colleagues that he worked with over long periods of time. You know, Margaret and Jeffrey Burbage and Willie Fowler. And then when we mentioned earlier that the Nobel Prize, Chandras Akar, getting in 83, and so did Willie Fowler. And that was very desperately sad for Fowler and Hoyle because they were such friends and Bala knew that Hale should have shared the prize with him because had it not been for that visit to Caltech in 1953,

Fowler said I would have been a run-of-the-mill nuclear physicist. And in fact, he actually worked out, he'd actually been able to prove the, what we call the carbon-nitride oxygen cycle, which generates heat, in massive stars. So he had done something. But the actual discovery of where all the elements came from, that was due to Fred Hoyle in 1953. So, you know, that was so sad. I, Hoyle told me that he was very, very upset for three days. And then, you know, Groglin Bell, he said, well,

I know the history books will remember that I did this. But it was, it was very, very sad. Because, I mean, there was a man called Jacob Bronowski who did a big TV series in Britain. And he he said a genius is someone with two good ideas. I all had two good ideas. He definitely had a state theory, which was wrong, but it was testable. It was testable. And it turned out that the universe was born in the big bank. And he was wrong. But it made testable predictions. And of course, he figured out all the heavy and all the elements in our body come from. So he certainly had two good ideas. Marcus, this has been a delight. I think of you whenever I think of a very clear, crisp explications that turn math and mystery into meaning for telling the human stories.

And I think Blackhalls are, in a sense, the universe's refusal to explain itself. You can, as your late great friend at Caltech, Richard Feynman said, you can dance with nature, but she won't let you dip her and lift her veil, something like that. And I want to just thank you for the great work that you're doing. And where can people find out more about you? Thank you very much. I've really enjoyed our conversation. Well, I've got a website called www.w.

Marcus Chown. So it's N-A-R-C-O-N.com, C-O-N. And you can get my book, if you want, from Barnes & Noble or Amazon or any of these places, hopefully in bookstores in America. We had a real problem recently. We had a cyber, the publisher had a cyber attack. So they weren't able to reprint that.

I think they've reprinted by now. Maybe it fell into a black hole, you know, the cyber. Marcus, thank you so much. I'll let to get back to your evening, and I just want to thank you again for this wonderful book, A Crack and Everything, and that's how the light gets in. So now we'll ring the bells that still can ring. Thank you, Marcus.

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