170. Finding the God Particle

26:25Your most recent book is on black holes. We're talking about black holes. I think, like many people, my first real introduction to black holes was Stephen Hawking's book, A Brief History of Time. And I think that book must have come out in the 1980s and it sold millions and millions of copies. Probably one of the best-selling science books of all time. As you set out to write a book about black holes, did you have that book in the back of your mind? Yeah, I mean, it was one of the books that really inspired me when I was thinking about going into physics. And Stephen Hawking is central to the modern story of black hole research.

27:00The reason Jeff Forshaw and I, my colleague at Manchester, decided to write the book was we became interested in something called the black hole information paradox. And I was getting asked about it increasingly in interviews like this, for example. You know, it's not my field. I'm a particle physicist. The study of black holes is partly particle physics, but also it's about general relativity and gravitation. And so we thought we would like to learn about some of the really interesting results that are coming out in the context of black holes. And just to put it very simply, Stephen in 1974 discovered that one of the things a black hole does is it shakes particles out of the vacuum.

27:45So there's loads of ideas here, but the vacuum of space is not empty in quantum theory. It's got a rich structure and the black hole sort of disrupts that structure. What ends up happening is the black hole glows, there's a temperature. And by the way, if you go to Westminster Abbey and look on Stephen's memorial stone in the abbey, you'll see his equation for the temperature of a black hole chiseled in stone on the floor of Westminster Abbey. So why is it important? It raised a series of profound questions. And one of them is what happens to stuff that falls into the black hole. Because it seemed, according to Stephen's calculation and what we understood at the time, that everything that goes in would be absolutely erased from the universe.

28:28One of the issues with Stephen's calculation is that if this thing is glowing, this black hole, so it has a temperature, it's emitting particles, then at some point in its life, as the universe expands and cools, the thing becomes hotter than the universe. They're way colder at the moment than the universe. But at some point, the universe cools down. They become hotter. So they start losing energy to the universe. And essentially, they radiate away. They disappear. They don't have an infinite lifetime, these things. So that was one of the consequences of Stephen's calculation. So one day, the black hole will be gone.

29:05All that will be left is the Hawking radiation. And what Stephen's calculation suggested is that no information is contained in that radiation at all. which is not surprising because the language I used earlier is it's shaken out of the vacuum of space. So it's got nothing to do with stuff that falls in. This radiation is coming from the vicinity of the event horizon of the black hole. So if an astronaut jumps into the black hole, for example, in Einstein's picture, they just go to the singularity, which is properly thought of as the end of time inside the black hole. So they go to the end of time.

29:43So the question was, it looked like black holes were erasing information from the universe, but the laws of physics that were used to make that statement and make those calculations do not allow for information to be erased. They allow for it to be scrambled up, but not erased. So this became known as the black hole information paradox. And so that's really the heart of the interest, the theoretical interest in them from the 1980s onwards. Because that's great, going back to what we talked about earlier, the thing that a physicist likes is a paradox. You want your whole theory to collapse if you can.

30:19And it did look as if the whole theoretical structure was in danger because of this apparent prediction that black holes destroy information. Now, it's interesting to hear you talk as the science communicator, because when we were talking about the Higgs, I don't really understand it, but I can at least pretend like I understand it. And I remember when I read Stephen Hawking's book 40 years ago, I don't even think I could pretend to understand it. And actually, I've made a conjecture around that book that that is the single most unread book in history. Everybody felt like they needed to have a copy of that book in their collection, but regular people just couldn't read it.

30:58It's interesting because talking about black holes is just categorically difficult to do because I don't think it makes any sense to regular people. So it sounds like a criticism of you. You just tried to explain black holes in maybe like a minute. But I will say your book, I actually understood a long ways. It gets really hard at the end. But I was with you for about 90 % of your book. And I want to give you a big compliment for that because you basically covered the same ground as Stephen Hawking. and you did it in a way that was really understandable and really exciting. It's exciting for someone like me to actually stick with you for 90 % of the book.

31:35Thank you. What you said actually about the book, probably 90 % of it is standard or 80 % of it maybe is standard physics. A lot of it's general relativity. That's Einstein's theory from 1915, his theory of gravity and gravity as the distortion in space-time. And that's, I think, quite easy to explain. I don't know about that. It's so crazy that time and space are the same thing. I find that mind-boggling. I teach at the University of Manchester, and I teach special relativity, which is the theory from 1905 that Einstein published, from which E equals MC squared comes. We teach that first year, first term in a physics degree.

32:22They're the 18-year-olds who are coming to university from school. It's the first thing we teach them because it's actually mathematically at least easy, but it's conceptually challenging for the reasons that you've said. what you see is that basically forced on to the physicists at the time, at the turn of the 20th century, was the idea that space and time are not the way we think they are. They're not separate from each other. They're woven together in a sense. I spoke earlier, moving clocks run slow, or moving rulers shrink, those kind of things. But that stuff follows very simply from a single assumption.

33:06The central idea is that the speed of light is a constant. It's the same for all observers. So literally, if you fly towards a source of light, like a flashlight or something, and you fly towards that thing at 99 % the speed of light, you will measure the speed of light hitting you in the face to be the speed of light. It's just a fixed number. Yeah, let me just put it a different way that you put it in the book because it was maybe the first time it's ever made sense to me. You use the example of cricket, right? If you have a cricket bowler that throw the cricket ball 80 miles an hour or something like that, but if you put them on an airplane and they throw it and the airplane's going 300 miles an hour, then when they release that cricket ball, it's gonna go 380 miles an hour.

33:55Okay, and that makes total sense to us. But the thing that is completely and utterly bizarre is that now if you use light and you put something that's going practically the speed of light, and then you throw something at the speed of light, it seems like it should be the speed of light plus practically the speed of light all added together, but it's only the speed of light. That's bizarre. Yeah, and Einstein was the first to take it absolutely literally and say, it appears that this is the way that nature is. What are the consequences? And it's very easy to work out the consequences. The hard thing is to accept what we've just said.

34:33It's counterintuitive. It was strongly suggested by results in electricity and magnetism back in the 1860s, particularly the work of someone called James Clark Maxwell. So it was around this idea for 40 years, I would say. But Einstein did the difficult thing, which is to say, okay, I accept that, what are the consequences? I was surprised to find out reading your book that already in the 1800s, a few people were speculating about black holes. And this was before Einstein. And obviously, they didn't get the physics quite right. But what kind of arguments were they making? I found that really interesting.

35:11So Laplace, who's a very famous French mathematician, and also an English clergyman called the Reverend Mitchell. It's interesting how often the reverends pop up in old science. Yeah, I think they were people who had space to think. So these two, apparently independently, were thinking about something called escape velocity, which is the speed you have to travel from the surface of something to completely escape its gravitational pull. So from the Earth, it's about 11 kilometers per second. That is so fast. That's seven miles per a second. So the rockets were shooting. I actually didn't realize we blast those things off.

35:52They really are going fast. Oh, yeah. You look at the Voyager spacecraft that are heading out, as we speak, 50 years after launch into interstellar space, they've achieved escape velocity from the solar system. And they're traveling very fast. Obviously, if you go bigger, let's say you go to the sun, then clearly the gravitational pull at the surface is stronger than it is on the Earth's surface. Turns out the escape velocity is about 620 kilometres per second. It's extremely fast. So that was known. You can calculate that using Newton's laws. And so what Mitchell and Laplace thought is, well, is it possible there are stars, and they were thinking of stars, that are so massive, and they were thinking of enormous stars, that the escape velocity at the surface exceeds the speed of light?

36:40Why not? If such a thing existed, you wouldn't be able to see it because you'd have to go faster than the speed of light to get away. So that's what they were thinking, which is, I think, a really nice idea. And Laplace called them dark stars. I always remember the quote he said in a paper that he wrote, that the largest objects in the universe may go unseen by reason of their magnitude. Now, it's interesting because the thing that they got wrong is actually the black holes that do exist, it's because the huge amount of mass shrinks down to be incredibly small. Because when you look at the formula, the closer you are to the center of the thing, the more the gravitation.

37:21So they got that piece wrong. This is 1790 or something. So they're just thinking, how do you make the gravitational pull really big? Well, you make the thing big, right? Perhaps paradoxically at first sight, you can also make the gravitational pull at the surface of something larger by shrinking it. They didn't think of that. And it's quite radical. It turns out that if you take the sun, which is 700 ,000 kilometers in radius, what's that? 400 ,000 miles or something, and you squash it to a radius of three kilometers, so two miles, then you can calculate that the escape velocity at the surface exceeds the speed of light.

38:02So that's ridiculous if you think about You can take the sun, which you can fit a million Earths inside, and squash it down until its radius is three kilometres. Surely that's not going to happen. Probably that's why they didn't think of it, because it's ridiculous. That's what you call a black hole, a thing that traps light. That was realised very early on. We're talking about 1920 or so, or something like that. But the debate into the 1960s really was, could nature do that to a star? So surely you would think if a star runs out of nuclear fuel at the end of its life and collapses, then surely something's going to stop it collapsing down to such a ridiculous state.

38:48But actually in 1963, roger penrose calculated that this will happen for a sufficiently massive star or anything else actually just a sufficiently massive thing no matter what and roger got the nobel prize in 2020 for that paper so it's not actually that long ago that people were debating these things and if you think about it it's only the last five or six years that we've really had an image of one which is from an experiment called the event horizon telescope which is basically radio telescopes linked together across the face of the earth an iconic image now of the black hole in the m87 galaxy which is six billion times the mass of the sun it's an astonishing thing super massive black hole and now we also have an image of the one in the milky way galaxy which is a bit of a little one about six million times the mass of the sun ish so it's a baby one and so just to play into all the fears that regular people have so we have this black hole what's it called sagittarius A star or something like that?

39:50That's the one in the Milky Way. Yeah. And so should regular people worry about that black hole sucking us in in regular time frames? That's the thing. They don't suck you in. If you turn the sun into a black hole, then the planets would carry on orbiting the way that they do now. And that's what happens in the Milky Way. And in fact, the Nobel Prize was awarded for looking at the orbits of the stars around the black hole, the Sagittarius A star black hole. So there are these stars called the S stars that orbit extremely close to the black hole. Because we can see the orbits, we can infer that there's something extremely dense and extremely small at the centre of the Milky Way galaxy.

40:34And essentially the only thing it could be is a black hole. In order to go into it, you have to fly at it. It's a deliberate act to jump into a black hole. So all this starts to make a little bit of sense, but we talked about already that nothing escapes from black holes. But then Stephen Hawking has that famous quote, which is, black holes ain't so black. And this now gets into this absurd quantum stuff that I don't think regular people like me have any chance of understanding. The other thing I haven't talked about is the event horizon. What is that thing? In Einstein's theory, it's just a region of space.

41:13You can think of it as kind of an imaginary sphere. Let's say this is a big, supermassive black hole, a billion times the mass of the sun. Then you can imagine this region of space, which is perfectly spherical if the thing isn't spinning. And so for a big black hole, you could be sitting there in the room that you're in now, or if you're in a car listening to this, you could fall in and you wouldn't notice a thing. You'd notice nothing. You would have crossed though into a region of the universe from which you cannot escape. That's what the event horizon is. It's the dividing line really. So if you're outside the horizon, then you can get away with a sufficiently powerful rocket.

41:57If you're inside, you cannot. And there were two beautiful ways of thinking about that to my mind. One is, which is a bit more abstract, is that you could think of space and time being distorted so much that they essentially swap roles inside the horizon. So the singularity, which imagine these big stars collapse, let's say, to form a black hole, you'd probably think of an infinitely dense point sitting there where the star was in space. But actually, you should think of this thing as a moment in time. And if you think of it as a moment in time at the center of the black hole, the switch happens when you cross the horizon.

42:39It's like, if you say, I want to run away from that thing, I want to get away from it. It's a thing in your future. It's in your future. So it's like trying to run away from tomorrow. So that's one way to think about it. The end of time lies inexorably in your future if you cross the horizon. But the other way, which is maybe more intuitive, is something called the river model. It turns out you can rewrite the equations that describe how the black hole forms more precisely what the black hole is. You can rewrite them as a river of space flowing in. It's like a sinkhole or your bath where you unplug the plug from your bath and all the water goes down the plug hole, right?

43:19You can rewrite it like that. and it turns out that on the horizon the space flows in at the speed of light so that means that if you're something trying to swim out then even if you swim at the speed of light you're frozen on the horizon because you're trying to swim out at the speed of light and the space is flowing in the river of space at the speed of light so you're stuck there and that's a really beautiful way of looking at it and it goes faster than the speed of light inside so no matter how fast you swim you're going to the plug hole right so that's what the horizon is and Stephen Hawking calculated that in the vicinity of that thing when you think of quantum mechanics which is what your question is then you find that particles real particles are emitted from space basically and that's the Hawking radiation so that brings us on to quantum mechanics and what is it you're listening to people i most admire i'm steve levitt and after this short break physicist brian cox and i will return to talk about his time as a pop star

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45:52Before Brian was a physicist, he had a moment as a pop star. His first big break was in a band called Dare that was founded by one of the members of Thin Lizzy. The name Thin Lizzy probably doesn't mean much to my younger listeners, but to some of my generation, Thin Lizzy was a big deal. I asked Brian how he managed to finagle his way into a band with a member of Thin Lizzy.

46:17It was luck. I got interested in music, just as everyone does when you're a teenager. And so I learned to play, not really very well, but I taught myself to play keyboards. And I made a demo tape when I was 16 with the band I was in. and Darren Wharton, who was a keyboard player from Thin Lizzy, had moved in close to where I lived in Oldham near Manchester for some reason. I don't know why. And he used to go in the pub with my dad and my dad took him the demo tape. And then when Lizzy split up, he formed a band in Oldham and he remembered that there was a guy who played keyboards up the road and he asked me to go down and audition.

47:00I wasn't a very good keyboard player, but what I was good at, and this probably is not surprising given my future career, is I was good at the tech stuff. So I could take these keyboards and these old synthesizers as they were. We're talking mid to late eighties now, it was all a bit complicated and I could make them work. I think he recognized that and thought, well, there's a guy here, he looks okay and he can plug wires in and he understands MIDI and all that kind of stuff so it's good so i got in the band so i took a year off university and i did we call it a gap year in the uk and in that time the band got a record deal with a and m records and so when i was supposed to be at university i found myself ultimately in los angeles recording and i'd only been out of the country once and suddenly i'm in la recording an album at joanie Mitchell's house with Larry Klein he's still a great producer Larry and he was married to Joni at the time so we made the album an album called Out of the Silence which I still like by the way I think it's a really good late 80s kind of soft rock album then they called us up A &M and said okay you're going to make a video for the song and then they said oh you're touring now you're going to support Jimmy Page and then ultimately we ended up supporting Europe the band Europe who had a big hit in the final countdown in North America.

48:25It was just bizarre that I went from this guy, and I was basically going to do some physics or something at university, to recording albums in Joni Mitchell's studio and touring with Jimmy Page. Was the touring the kind of rock and roll debauchery that we associate with the 1980s? Yeah, we had a good time. We were late teens, early 20s, a band from Oldham. Just kids from North Manchester who had no sort of interaction with that world at all. And it was a wonderful thing to do, as you can imagine. So we made two albums, toured a lot, then basically had a fight in a bar in Berlin, as you do. The band actually didn't split up.

49:12It's actually still going. But I left and the guitarist left and I went to do physics at university. Okay, so you say that. But even crazier is you then joined this band, D-Rheem, in 1993, just in time for this incredible song. It's called Things Can Only Get Better. And it's a number one hit for four weeks in 1994. I mean, that's just so crazy.

49:41Lucky, again, we had the fight in the bar in, I think it was October. and that's optimally bad if you want to go to university because university starts in september you've got to wait a year to go so in the intervening year i needed a job and i got a job as a sound engineer and sort of a tour manager and one of the bands was d ream who didn't have a record deal and then they got a place on a tv show a local tv show in london and they didn't have a keyboard player so they said to me well you know how to play keyboards don't you and you look okay so you just stand there and play the keyboard so i did that and accidentally joined the band and as you rightly say then that album ultimately became a really big album and we toured with bands like take that we had some big tours and ended up on this show called top of the pops in the uk which is the show that everybody grows up with and wants to be on and so yeah i did it again by accident when I was at university.

50:44And then crazier than anything, this is the song that then gets adopted by the Labour Party and is played all the time. It's like part of Tony Blair's celebration, right? Yep. 97, a very famous election in the UK, and the Labour Party asked us if they could use the song, Things Gonna Get Better. And we said yes. At that time, I think Tony Blair was the most popular politician you could imagine. And he was definitely going to become prime minister. And everybody basically voted for lay-by. It became iconic, this song. And it actually came back because we had an election last year in the UK. And it was a similar feel.

51:24It didn't quite work out that way with the optimism. But at the time, there was a sense of change. And so the single went back into the charts again last year. Every time there's a real election that signifies change and optimism, that song comes back. And we ended up getting the band back together and playing at Glastonbury. Oh my gosh. So I could never quite escape music, but I love it. Tell me about your upcoming world tour called Immersions. What's that? Yeah. So it started with giving public lectures in physics and they got more popular. And I started to think more about how I could broaden the audience because I've always said that science is too important not to be part of popular culture.

52:04And I really mean it. And so the opportunity came up to put that into practice and do some bigger shows and they've ended up very big and so in the uk now they're arena shows so they go to 15 000 people and then you really have to think about what you do so you start using enormous led screens and you start commissioning graphics and also the images from things like the james webb space telescope vera rubin observatory all are so high resolution that you can put them. I think the screens are a hundred feet across in the arenas. And so that tour emergence, I'm writing it now and we begin to do it next year.

52:44And I was inspired by Kepler. So Johannes Kepler, he's most famous for the laws of planetary motion. He figured out astonishingly to my mind that planets orbit around the sun in ellipses. and there's a relationship between the year, the period of the orbit, and the distance from the sun. Kepler wrote this book called The Six-Cornered Snowflake in 1610, which was about him walking across the Charles Bridge in Prague in a snowstorm and seeing snowflakes land on his arm and trying to understand why they're all six-sided. There's a wonderful quote from him where he says, this can't be by chance. There's got to be a reason.

53:25And it's a very modern way of thinking, actually. We started our chats by talking about the standard model and the Higgs boson, and I probably mentioned symmetries of mathematical equations. So regularities, they're what ultimately led to the standard model. Now, Kepler noticed there's a symmetry, which is this six-fold symmetry of a snowflake, and correctly thought, well, that's something about the underlying reason for these things. Now, it's a 20th century discovery. We know that's because of the shape of the water molecule. And why is the shape of the water molecule the way that it is? Because of quantum mechanics.

54:04And so we can do it all, but it's the 20th century. So I got fascinated by this mind that in 1600, that's a modern mind. He's a true genius. But also it's only 400 years ago. It's the birth of modern science. So in 400 years, roughly speaking, we're at the same time as Galileo, shortly after Copernicus. So we're at the birth of modern science. Now, I have to think, if you'd have taken an ancient Egyptian from, say, 3000 BC, and you'd brought them forward in time to ancient Rome, around 0 AD, 3000 years, they wouldn't have been too surprised. There's not a lot of change. So what is it about the way of thinking that those people and others discovered around that time that's catapulted us outside of our solar system in just a few centuries?

54:57All those worlds that Kepler saw as points of light in the sky, we visited them all. Mars, which was central to this, the laws of planetary motion, to understanding them. We've got rovers on it. We're searching for life on the surface now. We have spacecraft heading out of the solar system 400 years. And so there's a question, why? What is this thing we call science, this way of thinking and interrogating nature that's taken us from the end of the medieval period and onwards to the enlightenment and then to the stars, basically, in 400 years? And also what we might become if we can continue that exploration of nature and all the things that we've talked about.

55:43And we don't let superstition and darkness re-enter the world. Brian Cox's most recent book is titled Black Holes, The Key to Understanding the Universe. For more information about the Brian Cox Emergence Tour, check out the website briancoxlive.co.uk. That's b-r-i-a-n-c-o-x-l-i-v-e.co.uk. So this is a point of the show where I welcome on my producer, Morgan, to handle a listener question. Hi, Steve. So we have a question from a listener named Nick. Nick asks, why isn't there a requirement for gun liability insurance? It works reasonably well for cars. He thinks that liability insurance for guns would be a good mechanism to regulate the costs guns impose on society since direct government regulation doesn't garner enough political will.

56:43What do you think of this idea? So let's start with the underlying problem, which is that guns have a negative externality. And that's just economics jargon for when something I do imposes costs on other people. And there is a standard economic solution to deal with externalities, and it's to impose a tax, right? If you can figure out how much burden inactivity imposes on others, and then you levy a tax of that amount, it turns out after you work through the math that it leads to an efficient solution. So the most straightforward thing to do would be to impose a tax on guns. What Nick is saying, oh, that's not politically viable, maybe insurance, liability insurance, would be a way to get political support for this idea.

57:29I'll be honest with you, it's not an idea I've ever pondered before. And so what Nick is saying is when I own a car, I'm required to hold third-party insurance. So I don't have to have car insurance that covers my own collision damages, but I do have to have car insurance. So if someone else gets hurt in a crash that I cause, then I'm liable for that. And the idea is maybe you could do the same with guns. And at first blush, this seems like a reasonable idea. But I have to say, the longer I've thought about it, the less I like it. Really? So first of all, you start with a big problem that there are already laws in place that shield gun manufacturers and gun dealers from liability.

58:13Maybe those laws shouldn't be there, but they are. So if you want to think about imposing insurance, you're really talking about putting the burden on the gun owners. And once you start looking at the data, things really start to unravel because gun deaths take three forms, suicide, homicide, and accidents. And by far, suicide is the biggest number. Maybe 27 ,000 people per year in the U.S. are using guns to commit suicide. Clearly, liability insurance doesn't make any sense here at all. There's no third party to compensate. So this isn't dealing at all with the biggest source of gun deaths. The second way in which people die with guns is homicide.

58:55And there's roughly 15 ,000 gun homicides per year in the U.S. But there's two problems when you think about insurance. First of all, the majority of gun homicides are done with illegal guns. And one thing you can be sure of is that illegal gun owners will not be getting this insurance. So I just don't think it really solves the bulk of the problem related to homicides. But wait, and I don't have any data on this, but I feel like with school shootings, which we hear about in the news, often kids, high schoolers are taking their parents' legally purchased gun and bringing it to school and shooting classmates, teachers, people on campus.

59:39Well, it is true that a lot of attention is given to school shootings, and for good reason. The actual numbers relative to overall homicide is small. I think historically, if you looked at the numbers, we're talking about 30, 40 deaths per year. And obviously, that's 30 or 40 deaths per year too much. But it's really a drop in the bucket compared to the 15 ,000 homicides. So I think if you think about the machinery you would have to put around trying to do this, and it's probably politically infeasible anyway, it really, in the end, there've got to be better ways to compensate the victims of gun deaths than this.

1:00:15And I think it's very unlikely that any school shooter's behavior would be changed because of the existence of this insurance. I think far more important, potentially, in terms of numbers, would be accidental gun deaths. And looking at the data there, there are about 500 accidental gun deaths a year. And many of those, I imagine, are with legal guns. But the thing is, when you look at the data, about 90 % of accidental deaths are of friends and family. So again, you don't really have this innocent third party unrelated to you that needs to be compensated for the mistake. So in the end, what's ironic about this is that if you actually had this insurance and the insurance were there to compensate third parties who were strangers to you for legal gun ownership, I think the result would be that the insurance premiums would be really low because the actual risks that come from legal gun owners to strangers turn out to be really low.

1:01:17So you really don't think that requiring gun liability insurance is a good policy? I don't. But I have to say that thinking through it was a really valuable exercise for me. And it clarified my thinking in all sorts of ways. Nick, thank you for such an interesting question. Listeners, if you have a question for Steve Levitt or a problem that could use an economic solution, send us an email. The show's email address is pima at freakonomics.com. That's P-I-M-A at freakonomics.com. We read every email that's sent and we look forward to reading yours. Next week, we've got an encore presentation of my conversation with bestselling author Suleika Jawad.

1:02:06And in two weeks, it's a brand new episode featuring my friend and colleague, economist Michael Greenstone. He's doing economic research that is more important and policy-relevant than just about anybody else I know. As always, thanks for listening, and we'll see you back soon. People I Mostly Admire is part of the Freakonomics Radio Network, which also includes Freakonomics Radio and the economics of everyday things. All our shows are produced by Stitcher and Renbud Radio. This episode was produced by Morgan Levy and mixed by Jasmine Klinger. We had research assistance from Daniel Moritz Rapson.

1:02:44Our theme music was composed by Luis Guerra. We can be reached at pima at freakonomics.com. That's P-I-M-A at freakonomics.com. Thanks for listening.

1:03:01I'm sorry that I have everything in kilometers, right? The fact that Americans still don't know kilometers 50 years after the rest of the world changes is like a sad statement. We should be punished for that.

1:03:15The Freakonomics Radio Network The hidden side of everything

1:03:23Stitcher

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