How Black Holes Work

um video series called stuff you should Know that. Um, that's copyright infringement. I don't know. I think he's been dealt with. Actually is Yeah, that's what happens. And it's not about thick stuff you should know. I mean, it's really I don't know why you called it that. It's weird. What's it about? Just go watch it? Everybody out there watch it, right, We're just gonna boost him to fame. Huh. Um, Chuck,

have you ever seen a black hole? Um? No, no you haven't, and you know why because no one has. They're invisible. As a matter of fact, we can't even say that they are real. If you're an empiricist and empiricism if you forgot your philosophy. One oh one is the idea that nothing exists unless you can detect it with your senses one or all of the five senses. Do you know who champion that I'm just asking? Let's say Bacon. Okay. I thought you were gonna say Decart,

but I don't think so. No. Deck Cartes was more into himself. He talked a lot about the eye. Yeah. Yeah, Um, I'm gonna say, Sir Francis Bacon, all right, Okay, I'm probably totally wrong, but not love Bacon. Empirically speaking, black holes don't exist because we can't detect them. We can't hear him, although I have heard that they do make a sound. Yeah, and I have. Morgan Freeman said that we can probably hear them before we could see them.

The reason we can't see them. So let's just say, if you are um part of hearing or deaf, okay, and you can't taste, yeah, and you can't touch you, you have no sensations. It's just your eyes that you rely on. Black holes will probably never exist to you. Got you? That's my inter that's good, Thank you. This one melted my brain a little, have to admit I was expecting a brain melt. But I thought Fred and Rick, Fred and Rich. We've never figured out how to pronounce

his name. Let's go Rich, the only um writer that how stuff works with a PhD. That's what they toss him, ones like how black holes work. He I thought he did a decent job. I think it's a high time we get our honorary PhD. Where would you want yours from? I don't know, some I don't know. Maybe Georgia. Okay, why not I take a doctorate from Georgia that I didn't have to lift a finger for. Okay, well we just put the call up. My dad got a doctor

from Georgia. Yeah, but he got a real one. Yeah. Sure, he had to write the whole thesis and all that stuff. Do you ever call him doctor? Uh No, but that's what he You know, he went by the whole time, Dr Bryant. If you got an honorary doctor, you could do that whole um spies like us thing with your dad doctor doctor. Yeah. Yeah, we're really stalling on this one.

Don't want to talk about black all right, I'm gonna kick it all off, all right, So black holes we don't know that they exist for certain, although yes we do. You can't see him, I guess, is ultimately what I'm saying. But um, there was a real lag in between the time that they were predicted to exist, um, before we started figuring out how to detect them, and we detect them indirectly. Sure, but um, A lot of people say Einstein was the first one to predict black holes. Not true. Yeah,

this blew me away. Oh yeah, this dude, yeah, pretty smart. Uh what's his name? Pierre Simon Laplace? And he used Newton's theory of gravity and he said he calculated, you know, if there's an object compressed small enough, um, the escape velocity of that object would be faster than the speed of light. And he was like right on the money, Yeah, which means that nothing can escape this, including light. Yeah, because if light can't escape it's the fastest thing around,

then nothing can. Yeah. I guess we should just say simply straight up. First of all, I still haven't even said what it is. Yeah, it is what remains after a former star um collapses upon itself, after Gordon Webb collapses upon himself, either by super nova, which is a little more um explosive. I understand it's dramatic um or. I just learned this term and nova. Have you heard of that? No, I haven't. I think that's newer on the scene, and that is a little a little more anticlimactic.

And that's when a star will just sort of disappear. It's not a big explosion. It just kind of shrinks and collapses. It's like the credit Garbo of black Holes exactly. So, uh yeah. Or an un nova. I've not heard of that one. I watched through the Wormhole today and there was a guy just going on and on about the unknova. Yeah. Yeah, He's like, seriously, they're so understated. It's okay. So, uh well, let's let's just give a quick primer of what a

star is. The star is essentially a big fusion reactor, right, So there's nuclear explosion after nuclear explosion. It's constant and they're massive, and they want to blow the star, which is a ball of gas outward. But you have another force called gravity, which is trying to draw the star inward toward its center. So you have this interplay, this push and pull between nuclear explosion and gravity, and that

defines the star. Yeah, the equilibrium between the two. Yeah, and as I understand it, as they have these reactions, they're actually burning up these gases in like a specific order, even until eventually there is none left. Is that right? Right? Yeah, Gravity is always gonna win out because the star is going to spend its fuel, right, Okay, So when the star spends its fuel, gravity, it's like, ha ha, I got the better of you, and I'm going to start

pulling in like I've always wanted to. And it compresses everything. And then in the case of a supernova, the supernova happens that explosion, right, Yeah, it sends stuff all out all over the place, and then what's left is a core, but it's a super compressed core, which is fairly small, the most dense thing you can imagine. Right. So, our Earth has a gravitational field. It's a pretty massive body.

Comparatively speaking, it's a speck, but to you and me, it's pretty big, and it's big enough so that the gravitational field prevents it from from being sucked inward. Right. But if the Earth were smaller, the gravitational field will get stronger and stronger because the more dense something is and the smaller it's radius. As I believe, is how they put it. Astrophysically speaking, the stronger the force of

gravity acting on that. So the gravitational field around that small object, like the core of a dead star um is incredibly strong. Right. So you've got that core and this gravitational feel acting on it, and gravity just keeps pressing and pressing and pressing until the thing actually sinks into the fabric of time and space. And my friend, you have a black hole. Now do you have a hole in the fabric of time and space? Yeah, you can't see into it. You can't send anything into it

to report back. Well, yeah, that's the caveat. You can send whatever you want into it. It ain't it ain't coming back. It will. It will swallow anything that crosses the event horizon like mouth. Yeah, it's like the rim, right, but it doesn't. Just like, uh, this thing I read and we need to give a shout out to Hubble Hubble site, hubble site dot org. They have this great interactive thing on black holes. It's just really extensive. That's where you fly through space. Yeah, it's very cool. It's

pretty cool. Uh So they what's important to point out because I thought it was just like this vacuum that just sucked everything, you know, sucked everything inside of it and like killed it. Yeah, it dejects stuff even well, it ejects stuff, but it also doesn't suck anything into itself anymore so than anything else in space with similar mass. Yeah,

like vacuum cleaner. Right, Yeah, exactly. Like if we weren't going so fast around the Sun, we could potentially be pulled into the Sun, but because we're going around it like I think sixty seven thousand miles per hour, it prevents it from happening. And theoretically, if you could go super super fast around in an orbit around a black hole, you wouldn't get sucked in either, but you'd have to be in a perfect orbit. Okay, if you're off at all,

then bye bye. Okay, So you mentioned the event horizon, right, Um, that core, that super compressed core is called the singularity. Yeah, we don't know a lot about that um, and black hole has a lot of really cool quirky UM aspects to it. Number one one quirky. One thing I learned about this that I didn't realize is that black holes like move around space. Yeah, so, like you have a hole in space, the fabric of space and time. Because

time and space are totally intertwined, they can't be separated. Um, that's moving around, right, and there could be lots of them, right, So yeah, depending on the kind. Um, there's probably tens of millions of ones called stellar black holes, which are about anywhere between ten to twenty four times the mass of our Sun. And then there's super massive black holes, which are tens of millions to billions of times more massive than our Sun. And they think that there may

be one of those at the center of every galaxy. Yeah, and at the very least at the center of the Milky Way. Right. So the other quirky part, this is my favorite thing about about black holes, is so gravity, if it's strong enough, it has the capability of bending space that pulls on space spacetime. Yes, because space and time are intertwined, that means it also pulls on time. So if you get close to a black hole, um, and I think we talked about this a little bit

in the time travel episode. Uh, as you get closer to the event horizon, they drag on time will actually slow time for you relative to say the people back here on Earth because at the event horizon, the reason they call it an event horizon. Is an event is a point in space time and as you get closer to the event horizons, time slow until you hit the event horizon and time stands still. You're going faster than the speed of light. And once you pass that, there's

there's time to stops. That's a pretty quirky characteristic. The quirkiest great word for it. Yeah. Uh. The event horizon has a radius called the schwartz Field swatch Child radius. Sorry about that, And it's name for Carl Schwartzchild and he was one of the early leading theorists on black holes. And I think the radius, I believe where don't have that note if the Earth where to become a black hole. I think the radius is the size of a marble.

That's what you'd have to shrink the Earth down to. Yeah, pretty cool and very small. It's mind blowing. It is mind blowing. Um. And I think they the supermassive black holes like the supernovas have only I think they happen like once or twice per century. It's like we haven't observed one of these because it's too far away and it's too intermittent. Huh. But I think they're on the lookout and like the next time there is one, hopefully it's within the range that we can see or here

and the dude on through the wormholes. Like we wouldn't sleep for weeks if that happened, Like we'd be running so many tests trying to measure and uh, you know, see how big it was and how far away it is. And so it's a bit of a quandary. Do you think it will happen anytime soon? I don't know. I

don't know when the last one was. So we're you just mentioned the supermassive black hole, and they think that there's one at the center of every galaxy, right, um, And but there's there's kind of a mystery if black holes aren't mysterious enough, there's a mystery to like why there's such a huge difference in the two sizes the stellar black hole which is like ten to twenty four times our son, which, by the way, our son will never become a black hole on its own, it's too small.

The that guy Simon Pierre Loss or Pierre Simon Lapasse, he calculated that it has to be three times the mass of our Sun, So our son is like a third of the mass right, so it will never become a black hole, but it could become a black hole if it becomes a neutron star, or even as a star, if it collides with another star, it can form a black hole. It can be sucked up by a black hole to make an even bigger black hole. And they think perhaps, or I suspect this is the way that

they're headed. They think that a super massive black hole is just a bunch of black holes pushed together. Yeah, because I did read it. If they collide, they potentially would just like join forces. Yeah. And they think also that stars can collide and create bigger stars and bigger stars and bigger stars, and then when those die, they could on their own form a super massive black hole. But if it's at the center of a galaxy, probably what's going on. It's like if you have a sheet

and you put a baseball in the middle. Remember we were talking about wormholes, It kind of bends the sheet. So if you drop a marble on the sheet, it's going to go towards the center. So what I think is going on is that there's this there's super massive black holes at the center of a galaxy, and it just eventually everything is moving toward that to form a huge black hole. Really, that's what I think is happening. So we're yeah, but not in our lifetime. Well, who

cares about our children and their children? Yeah? I can't even conceive how far down there it is? Should we talk about? Um? The different too, A couple of two different types. UM, the Schwartz Child non rotating type, in the ker or ker Newman rotating type. UM. It's pretty simple. If the star was rotating before it collapsed upon itself, it will continue to rotate afterwards, for I guess as

long as it's around, Is that right? Yeah? It's the angular conservation of angular momentum, where like if something spinning, why would it stop? I think it's how to put like an ice skater pretty much. Uh. And the curb black hole is a little more complex. Um. It has the singularity which we've talked about, the event horizon, which you've talked about but you don't want to go near. Did you see that movie? I love that movie. It's one of my favorite horror movies. I need to go

back and rewatch it. You should because I remember liking it to a point and then not thinking it was so great, No you're thinking of yeah, okay, and never has a movie spectacularly fallen upon event horizon was Sam Neil, Right, yeah, okay, the class act he is, isn't he? Uh? And then there's the ergosphere and that is the UM egg shaped region. Basically that's the spinning part because it's dragging space around it,

so it's gonna have the shape. And then the static limit is the boundary between the ergosphere and what they call normal space. So there was something in here that UM and I couldn't find this time, but before I've found that a car ring, right, the rotating black hole.

UM doesn't have a singularity because the centrifugal force combats gravity enough so that the core can't be compressed enough to form a singularity, which is the whole reason why they think that that could potentially be used as a wormhole to travel through time bridge perhaps because with the singularity you have spaghettification, which is a real word, right, Um. Where As you get closer and closer to it, gravity just pulls you on an atomic and cellular level and

stretches you into like this dead string version of yourself. Right, But the centrifugal force prevents gravity from becoming that powerful around the carrying, which supposedly you should be able to go through it. Is that your theory? No, No, I've seen it elsewhere. I'm just saying, I don't know that caring or care black hole has a singularity. Dispute that, Okay, I got you. Um, And I think that the schwartz Child black hole does not have the ergosphere of the

static limit. Is that right? Yeah? I don't think so, just the singularity in the event horizon. Yeah, the swarts Child one is the one that you think of when you think of a black hole. Oh, isn't Huh. It's just like a black hole. It's got a singularity, it's got the event horizon. Can escape caring, light can escape, and things can become injected, and if you get up enough speed you could pass by it as long as you don't cross the event horizon. Man, there's so many

rules I know. And plus it's all theoretical too, or not all theoretical, but a lot of it is because if you could only see. Yeah, we don't even know that black holes exist, what we do? Um, but we can detect them in a few different ways. Is that right? Uh? Three? Ways mass um mass estimates. So basically you can't necessarily measure a black hole, but you can study the things swirling around it. Get some idea from that about like

how big it is. Yeah, it's Kepler's third law of planetary motion appropriately enough, and that it says that the time of orbit squared equals the average orbital radius cube, which somehow translates to mass. But basically, if you watch something spinning, first of all, you have to say, why is that thing orbiting something that we can't see? Yeah, is why is it wobbling? Right? If it's wobbling and um, if if you can, if you trace its orbit and um,

take that to the second power square it. Uh, if that equals the mass of three times or more of the Sun, then you probably have a black hole. You've probably detected a black hole that's in the vicinity of that thing that you're tracking. So basically, this thing is acting like it's near a black hole and there's no other reason, right, we can pinpoint, so it must be a black hole. Yes, is simple enough gravity lens Uh. Einstein predicted that you could be in space. Pretty smart dude,

and he actually confirmed this. Actually did he confirm it. No. He basically theory of general relativity and special reality. He just made a bunch of predictions that was like, you guys, go out and figure it out, and everybody did and if he was proven right, so it was confirmed during a solar eclipse, star's position was measured before, during, and afterward, and the position shifted because light was bent by Sun's gravity. Yeah,

pretty amazing. It was like here I am here, you am here, I am And another um effect that a black hole can have as far as lights concerned, as um, it can concentrate light by bending it by that gravitational lens. So a star can become brighter all of a sudden, And when you can't see what's doing that, you must assume that a black hole passed in between your line of sight and the star, sort of like a eclipse,

right all right? And then uh, emitted radiation. This one makes a lot of sense because it emits um X rays because of the heat generated when something falls into the star. And you can actually measure and detect these X rays, right, So, and that's just X rays camera rays too, apparently. Yeah, but this this stuff, it's called acretion where if something is swirling around a black hole and it goes in or it's sucked into the swirl around a black hole towards the event horizon through gravity. Um.

That's called acretion. And what I don't understand. I didn't think black holes spit anything out like I thought they were the cosmic vacuum cleaner too. But it turns out they can spit out matter, and when they do, they form these things called jets. So if you see a solar system um or um a galaxy and there's a lot of matter flying out in these concentrated forms called jets,

there's probably a black holder. All right, Well, I went to the Hubble site and picked out a few questions about black holes that are I think helped clear up a few things at least did for me. Do black holes live forever? I'm going to say yes. No. Uh, we used to think that actually, so you were thinking with your nineteen three brain. Stephen Hawkin came along in nineteen sev and uh showed that they actually evaporate over time really slowly and just sort of emit their energy

back into the universe. I'm just kind of sweet, I guess, yeah, yeah, But I don't understand how like the core burns out or the core breaks up. I don't know. He just said they slowly evaporate, And who am I to argue, Um, how large are they? The size and event horizon is proportional to the mass of the black hole, and so they found them, um with event horizons from six miles to the size of our entire solar system. So yeah,

big big differences in size, like you were talking about. Yeah, Um, I can't remember the name of the the galaxy, but there's a galaxy that's like the size of our solar system at the center, but it has a mass of like one point two billion times in size of our Sun. So they're like, okay, there's probably a black hole there. This is when my brain starts melting. It's like, you can't even can see I can't even conceive this stuff.

I know. We're like just we're talking about like the layman's interpretation of you know, the stuff, Like we're not even throwing numbers out there. Yeah. I don't mean, I don't feel too bad because the more I researched it, the more I saw a lot of really smart people saying like this is mind blowing stuff, you know, So I'm not that big of a dummy. What types are there? I think we already said super massive or stellar maps.

Can you safely orbit of black hole? You can if you, like I said, I was gonna say, now if you get in the exact right circular orbit, but it's very unlikely that that would happen. But once you the event horizon, that's that toast. Uh. And then what is inside a black hole? Because we cannot glimpse inside of it, we don't know for sure, but they think that the singularity is like they think everything is piled up in the center, like just stacked up, like whatever it's sucking in is

stacked up at the center. But to understand it fully, um, they're having to marry basically two different um parts of science, which is quantum mechanics and gravity. And they've even named it quantum gravity. And they don't they don't know how that stuff works, but they did name it. Well at least that's at yeah, and the Hubble site said it's it's uh, one of, if not the most important unsolved problems in physics. Still, so yeah, because there's like a

whole in this fabric of space time. And Morgan Freeman thinks in the black hole could be the answers to everything I wonder. I've also wondered like if if say, the Singularity is really just forming a tunnel, does it break through? Can you break through space time? Or is it really just like a like a well because you know, well it doesn't go all the way through the Earth.

Morgan Freeman talked about it. Well, that's funny. Well I mean that, but that's I think what it is, because something has to hold the Singularity in place, right, It's got to be butted up against something. So I wonder if it's just pressed down to a degree that gravity can't push it any further, or is it something that's just like punched through and we assume that the core still there but it's long gone, right it's in China. Good question, they'll answer it in I just read um.

You know, our friend Joan d Azo, he recommended these books to his time travel books. I read one of him over the weekend. The Man who Folded Himself highly recommended, Very trippy. Written in nineteen seventy three. It's like one of those you know, and uh, it's nonfiction. It's it's about a guy who gets a time belt from his uncle's nonfiction. What did I say? It was nonfiction? No fiction? Who is this man? Uh No, it's very much fiction

science fiction. And he gets a time belt from his uncle that basically, um, he subscribes or the author ends up subscribing to the mini worlds theory because every time this guy time travels, he creates a different version of himself in a different world, but they meet up, so he ends up he ends up having a relationship with himself, really, and then he ends up having a relationship with many of himself, like has a relationship or makes relations he he has sex with himself, and then he has an

orgy with himself and then that is it is. Dude, when you're reading it, you're like, you get to see this guy like he's from California's and then he eventually, um, there are female versions of himself created in these different realities, and he has a relationship and gets his female self pregnant and has a little boy who ends up becoming who he was, and he delivers the time belt to him at the end. I guess it just ruined it. Yeah, that's pretty much the book. Yeah, it's well worth reading now,

I mean it's it'll like it'll melt your brain. Almost no fiction these days, anyways, thank you for that. It's good. You're like a walking cliffs notes. And it's it's short, so like you could read it. I read it over the weekend when I was at the cabin, so it was nice. And the Hunger Games. Did you read that really? Yeah? I read it in a day. How was it? Um? You know, it's it's those books like that are it's

like popcorn movie. You know. It wasn't bad. It really moved along and then we saw the movie and the movie stunk. Does it have like a like three page chapters? Is it like one of those books? Okay? I mean it was fine. You know, I don't know anything about it. It's the most Dangerous game. Oh that's a good one. I think there's an RC plane out it sounds like it. There's a couple of them. I think there's an RC

dog a drone outside office. So if you want to learn more about black holes, there's this really cool article on the site called how black holes Work. It's a pretty good approach. Initial approach too, black holes pretty understandable. Do you think you'll like it? Puts theres some neat pictures, UM type black holes in the search bar house to works dot Com, I said, search bar, chuck it down and read the listener mail. This is from Mark in

New Jersey, fifteen year old just smarter than me. Um. Hey, guys, I'm fifteen. I'm a big fan of the show. Find it very interesting and funny, and I listened to it whenever I have a long car ride. Right, boring, mindless task to accomplish. I was just recently listening to the Reagan Star Wars program. The Cold War and global thermonuclear war are perhaps my favorite topics. How about a nice game of chess. Chuck should read that part in a

robot voice, and you did. I was listening to the part about Um shooting off nukes willy nilly in space. You were wondering if that had a negative effect, and said some really smart guy at email the answer. Then I remembered something that's all on Discovery Channel. I don't remember all the details, but I believe Michio Kaku said nukes don't work in space because of the way they transfer energy. Adam to ADAM spaces a vacuum, so there was a lack of atoms to transfer energy through Um,

this is how he remembers it. At least. UM, I hope I was the really smart guy who helped to answer your question. Technically, Michio Kaku was the one is the really smart guy. But Mark with a C from New Jersey was smart enough to relay that information to us, and we we talked about this. We followed it up kind of inadvertently. Um, with the testing nuclear weapons that'll fall out, that's true, and it seemed like they were like the nukes worked right, I guess worked enough to test.

I mean they made some crazy fireworks displaying this guy. But who am I did disagree with the Mischio Cockum exactly. Um, thanks a lot, Mark. We appreciate you being so smart and taking the time to write in. If you think you're smart, we want to hear from you. Tell us about black holes or whatever. You want show off your smarts to us. UM. You can tweet to us at

s Y s K podcast. You can join us on Facebook dot com slash Stuff you Should Know, and you can email us at Stuff podcast at Discovery dot com. For more on this and thousands of other topics, visit how staff works dot com. M HM hm