WEBVTT - Black Holes, Part 1: Phantom 0:00:00.160 --> 0:00:05.400 My World. Welcome to Stuff to Blow your Mind from 0:00:05.400 --> 0:00:14.440 how Stuff Works dot com. Hey, welcome to Stuff to 0:00:14.440 --> 0:00:16.640 Blow your Mind. My name is Robert Lamb and I'm 0:00:16.720 --> 0:00:19.119 Joe McCormick, and today is going to be part one 0:00:19.200 --> 0:00:23.080 of a multi part episode on on a topic that 0:00:23.160 --> 0:00:25.840 I know you came back from New York with a fever. 0:00:26.000 --> 0:00:30.160 For Robert, We're gonna be talking about black holes, that's right. Yeah, 0:00:30.200 --> 0:00:32.800 I attended, Uh, I attended a talk at the World 0:00:32.840 --> 0:00:35.919 Science Festival that I believe I mentioned in our previous 0:00:36.040 --> 0:00:38.879 sort of World Science Festival roundup episode that I just 0:00:38.880 --> 0:00:41.360 thought did a great job of providing an overview of 0:00:41.400 --> 0:00:44.440 black holes and uh help straighten out a few of 0:00:44.479 --> 0:00:47.280 the details for me. Yeah, I realized we have talked 0:00:47.280 --> 0:00:50.520 about black holes on the podcast before, but you haven't 0:00:50.640 --> 0:00:55.520 really I felt given it, given them proper, do We haven't. 0:00:55.520 --> 0:00:58.760 We haven't really uh looked at black holes with the 0:00:58.760 --> 0:01:01.920 attention that they deserve. Yeah, And of course, even in 0:01:01.960 --> 0:01:03.960 doing a multi part series, we're not gonna be able 0:01:04.000 --> 0:01:06.679 to cover every interesting thing about black holes. So this 0:01:06.720 --> 0:01:08.800 is gonna be kind of a grab bag of things 0:01:08.840 --> 0:01:12.000 that seemed interesting to us. So in this first episode, 0:01:12.040 --> 0:01:14.520 we're gonna be talking mainly about the history of the idea, 0:01:14.600 --> 0:01:17.160 where it came from, how we arrived at this bizarre 0:01:17.200 --> 0:01:21.120 conclusion about the cosmos that we live in. In the 0:01:21.160 --> 0:01:23.800 second episode, we're going to be focusing mainly on like 0:01:23.920 --> 0:01:26.679 how we get a look at these things. And in 0:01:26.800 --> 0:01:28.959 the third episode, I think we're gonna explore some of 0:01:29.000 --> 0:01:31.880 the strangest avenues of thought that you can contemplate with 0:01:31.920 --> 0:01:34.160 regard to black holes, like what's it like to fall 0:01:34.200 --> 0:01:37.640 into one? Or what happens when a black hole collapses? 0:01:37.720 --> 0:01:40.800 Does it does it create something on the inside? Yeah, 0:01:40.840 --> 0:01:43.959 And I want to acknowledge that black holes, I feel 0:01:44.000 --> 0:01:48.400 are kind of a challenging topic to tackle some people. 0:01:48.440 --> 0:01:50.880 I mean, certainly from a like a physics standpoint, yes, 0:01:50.920 --> 0:01:53.720 but but also just in terms of becoming engaged with 0:01:53.760 --> 0:01:55.240 the idea, because I know there are plenty of you 0:01:55.240 --> 0:01:57.080 out there like, yeah, black holes, let's do this. I 0:01:57.120 --> 0:01:59.920 love I love science I love science fiction. I think 0:02:00.080 --> 0:02:02.960 King of of all my favorite black hole related movies. 0:02:03.880 --> 0:02:06.800 But I know other people are a little hesitant because ultimately, 0:02:06.920 --> 0:02:10.800 black holes are a concept that have very little impact 0:02:10.880 --> 0:02:14.600 on our personal lives and the scope of the universe. 0:02:14.720 --> 0:02:17.600 That we observe and interact in. Well, they don't have 0:02:17.639 --> 0:02:20.839 any people in them, right. I mean a lot of times, 0:02:20.880 --> 0:02:23.400 I think when people look up to space and they say, 0:02:23.800 --> 0:02:25.840 you know, I want to be interested in it, but 0:02:25.880 --> 0:02:28.200 there's if there's no people up there, it's hard to 0:02:28.200 --> 0:02:31.359 feel like I'm following a story or narrative. Or can 0:02:31.400 --> 0:02:33.600 I even imagine a person there, because obviously there are 0:02:33.600 --> 0:02:36.040 no people on Mars. But I can, But I can 0:02:36.080 --> 0:02:38.320 imagine a future in which there are people on Mars. 0:02:38.320 --> 0:02:42.919 I can. I can imagine multiple different sci fi scenarios, 0:02:43.440 --> 0:02:48.760 many of which match up reasonably well with scientific expectations, 0:02:49.120 --> 0:02:51.680 and and that can allow me to engage myself in 0:02:51.800 --> 0:02:54.880 Mars more. But unfortunately, if you know anything about black holes, 0:02:54.919 --> 0:02:57.760 you know that it's not even possible to say colonies 0:02:57.840 --> 0:03:01.480 a black hole. You can't have singular and knots going 0:03:01.520 --> 0:03:04.360 in there to see what's on the inside. Or you could, 0:03:04.400 --> 0:03:06.280 but it just wouldn't be very useful for us on 0:03:06.320 --> 0:03:09.160 the outside, or I guess very useful for those getting 0:03:09.200 --> 0:03:12.840 ripped apart on the inside. Right. And I think another 0:03:13.040 --> 0:03:16.440 challenge with black holes is that when they have played 0:03:16.639 --> 0:03:19.960 a key role in science fiction and been made ultimately 0:03:20.040 --> 0:03:24.920 kind of relatable concepts. Uh, the films don't really do 0:03:25.080 --> 0:03:28.079 much with the science. They don't really do a great 0:03:28.160 --> 0:03:33.120 job about really conveying what a black hole is. For instance, 0:03:33.240 --> 0:03:35.840 I have to admit that my first introduction to black 0:03:35.880 --> 0:03:39.600 holes was the nineteen seventy nine Walt Disney sci fi 0:03:39.640 --> 0:03:43.200 movie The black Hole. Oh, Robert, I've never seen this one, 0:03:43.280 --> 0:03:45.960 but I'm excited. I'm excited for you to tell me 0:03:46.000 --> 0:03:48.520 about it. Tell me about it, fill my brain. All right, 0:03:48.720 --> 0:03:51.720 we'll just briefly. I'll try not to go on too 0:03:51.720 --> 0:03:53.400 long about this, because this is a film I loved 0:03:53.400 --> 0:03:55.640 as a child and I still look back on finally today. 0:03:56.320 --> 0:03:58.480 But it lands in a weird spot for a science 0:03:58.520 --> 0:04:01.680 fiction film because it's it's not as fun and original 0:04:01.920 --> 0:04:05.560 as nineteen seventy seven Star Wars, and of course it's 0:04:05.600 --> 0:04:09.680 nowhere near as high minded and scientifically savvy as ninety 0:04:09.760 --> 0:04:12.600 eight two thousand and one of Space Odyssey. But then again, 0:04:12.680 --> 0:04:15.840 you know what is Instead, it's kind of an old 0:04:15.960 --> 0:04:20.560 fashioned Jules Verne esque tale of space explorers who wind 0:04:20.680 --> 0:04:23.359 up on a space station that's circling a black hole, 0:04:23.720 --> 0:04:26.240 and the station's run by a mad scientist whose only 0:04:26.279 --> 0:04:30.920 attendance are robots and lowbottomized androids. There's ultimately some fairly 0:04:31.200 --> 0:04:34.240 horrific and and kind of ambitious stuff mixed in there, 0:04:34.400 --> 0:04:37.000 but you're also faced with just kind of a maximum 0:04:37.080 --> 0:04:42.240 dosage of of of of late seventies big budget cinema. 0:04:42.320 --> 0:04:44.560 Like all the actors you would expect to show up 0:04:44.600 --> 0:04:50.680 do show up. Ernest borg nine, Anthony Perkins, great, Maximilian 0:04:50.839 --> 0:04:54.440 Shell shows up as the villain. How about Harry Dean Stanton? 0:04:54.839 --> 0:04:57.240 Uh no, no, Dean Stanton, as I recall, And you 0:04:57.279 --> 0:05:00.800 also have one of the Bottoms brothers, timoth Bottoms, No, no, 0:05:00.800 --> 0:05:03.360 no one one of the other ones. Not not last 0:05:03.360 --> 0:05:05.960 picture was it last picture show? Yeah, less picture show, Yeah, 0:05:06.000 --> 0:05:08.960 not last picture shows bottoms, but but but one of 0:05:09.000 --> 0:05:10.920 the other ones some other bottoms yes, okay. And also 0:05:10.960 --> 0:05:13.320 slim pickings, slim pickings. Yeah, he's the voice of a 0:05:13.400 --> 0:05:16.400 robhid just busted up robot it had It is really 0:05:16.400 --> 0:05:19.320 cool robots in it. I gotta see this. The trailer 0:05:19.440 --> 0:05:22.120 is pretty great for it. H In fact, if we 0:05:22.240 --> 0:05:24.200 if we can play it, I would like to just 0:05:24.279 --> 0:05:29.640 throw in just a clip from this trailer. There is 0:05:29.680 --> 0:05:35.240 an inexorable force in the cosmos, where time and space converge, 0:05:36.880 --> 0:05:42.719 a place beyond men's vision but not to his reach. 0:05:42.600 --> 0:05:46.120 It is the most misdious and awesome point in the universe, 0:05:50.800 --> 0:05:55.720 whether here and now maybe forever. The black hole in 0:05:55.760 --> 0:05:58.440 this film, the actual black hole that we're presented with, 0:05:59.000 --> 0:06:02.640 it's it's it's presented like a vortex. It's it's more 0:06:02.640 --> 0:06:08.039 in keeping with the charybdis whirlpool of Greek myth. You know, this, 0:06:08.040 --> 0:06:11.640 this terrible thing that you're on the verge of falling into. 0:06:11.839 --> 0:06:16.520 It's ultimately treated with more religious reverence than scientific, which 0:06:16.520 --> 0:06:18.760 of course is pretty much what happens later on in 0:06:18.800 --> 0:06:23.000 the film Event Horizon, which I also love, but it's 0:06:23.040 --> 0:06:26.479 hardly a scientific tour to force. Were you watching Event 0:06:26.520 --> 0:06:29.960 Horizon recently, Robert, Yes, I was. I started watching it 0:06:30.000 --> 0:06:33.360 again last night, but only made it about ten minutes 0:06:33.360 --> 0:06:37.799 in before my ambient kicked in, because that's a horrible idea. 0:06:38.279 --> 0:06:41.120 It's it's not really not ten minutes end, because you 0:06:41.360 --> 0:06:43.160 get past the scary stuff and then you're just done 0:06:43.160 --> 0:06:44.800 a spaceship, and then you realize it's time to go 0:06:44.839 --> 0:06:47.159 to bed. I realized that the spaceship in that movie 0:06:47.200 --> 0:06:50.600 it's like the only leather punk spaceship I've ever seen 0:06:50.640 --> 0:06:53.040 in science fiction. It's like, you know, those like black 0:06:53.120 --> 0:06:56.280 leather wrist bands with the metal studs on them. It's 0:06:56.440 --> 0:07:00.159 that as a spaceship, it is very industrious, especially the uh, 0:07:00.760 --> 0:07:04.240 the core that you end up exploring. But but hopefully 0:07:04.279 --> 0:07:06.760 we'll get to talk about event Arizon a little bit 0:07:06.760 --> 0:07:09.159 more in one of the future episodes. But basically the 0:07:09.200 --> 0:07:11.600 idea is it's got a black hole and that's how 0:07:11.640 --> 0:07:14.520 you get to Hell. I think, yeah, which again is 0:07:14.600 --> 0:07:17.280 kind of the idea that has explored in Disney's a 0:07:17.320 --> 0:07:20.800 black Hole as well. So there's people in it, well, 0:07:20.920 --> 0:07:23.600 there are things in it, humanoids that you end up 0:07:23.600 --> 0:07:26.600 with characters traveling through it. It's ultimately the confusing part 0:07:26.680 --> 0:07:29.160 is that both films kind of treat a black hole 0:07:29.240 --> 0:07:32.920 more like a wormhole, which is a separate thing altogether, 0:07:33.360 --> 0:07:36.760 but that is ultimately more relatable I think to us 0:07:36.760 --> 0:07:39.400 the idea of like a magic tunnel that goes somewhere. 0:07:40.040 --> 0:07:42.280 But of course, actual black holes don't exist on a 0:07:42.320 --> 0:07:46.600 scale that that directly influences individual human life for life 0:07:46.600 --> 0:07:49.400 on Earth, except in our study of them. But the 0:07:49.400 --> 0:07:52.320 bottom line is that they're They're just a physical reality 0:07:52.400 --> 0:07:55.400 of our universe. They're not some sort of evil, malignant force. 0:07:56.080 --> 0:08:00.200 They are just a physical part of the universe. At 0:08:00.200 --> 0:08:03.200 the same time, though, I would say they are astounding 0:08:03.440 --> 0:08:06.000 and one of the most interesting things in the universe 0:08:06.080 --> 0:08:10.360 because they are the absolute extremists of of what we 0:08:10.400 --> 0:08:13.320 know about physics. They're sort of like the test cases. 0:08:13.400 --> 0:08:17.040 They're the exceptions. They break things that and that. For 0:08:17.080 --> 0:08:19.720 that reason, they're interesting to scientists because we can look 0:08:19.760 --> 0:08:21.920 at them and say, okay, what happens in these extreme 0:08:22.000 --> 0:08:25.000 cases where you know, where we can't necessarily see inside 0:08:25.080 --> 0:08:27.800 to know the answer. So at this point some of 0:08:27.840 --> 0:08:30.040 you might be asking, well, well, what is a black hole? 0:08:30.120 --> 0:08:33.240 Just lay lay out the basic definition. If it's not 0:08:33.360 --> 0:08:36.120 a wormhole, it's not a gateway to Hell, then then 0:08:36.160 --> 0:08:39.320 what are we talking about here? Well, in short, we're 0:08:39.320 --> 0:08:42.920 talking about regions of space where the gravity is so 0:08:43.000 --> 0:08:46.960 intense that light cannot escape the poll and the gravity 0:08:47.040 --> 0:08:50.080 is that intense because matter is compressed to a very 0:08:50.120 --> 0:08:54.000 small space and they range in size. For instance, primordial 0:08:54.040 --> 0:08:56.840 black holes are no larger than a single atom, but 0:08:56.880 --> 0:09:00.960 they contain the mass of a terrestrial Mount him So 0:09:01.120 --> 0:09:04.000 Mount everest crunched down to the side of an atom. 0:09:04.120 --> 0:09:08.800 It's pretty dense. A stellar black hole might be ten 0:09:08.920 --> 0:09:12.480 kilometers in diameter, but would boast the mass of twenty suns, 0:09:12.520 --> 0:09:18.000 for instance. And then finally you have the supermassive black hole. Uh, 0:09:18.320 --> 0:09:21.120 the types of black holes that that that that live 0:09:21.160 --> 0:09:24.080 at the centers of galaxies. Uh. And these would have 0:09:24.160 --> 0:09:27.600 the mass of millions of suns compressed to a sphere 0:09:27.679 --> 0:09:31.800 the size of a single solar system. That's extreme compression. Yeah, 0:09:32.080 --> 0:09:33.839 a little harder to even think about it. Like I 0:09:34.160 --> 0:09:38.240 find that the mountain atom uh comparison is maybe a 0:09:38.320 --> 0:09:41.959 little more impactful for the human imagination. But still we're 0:09:41.960 --> 0:09:47.480 talking about considerable, considerable consolidation of mass. Now we call 0:09:47.559 --> 0:09:51.000 them black holes because light cannot escape them. Optically, they 0:09:51.040 --> 0:09:54.320 appear as an absence. We can't see inside them, but 0:09:54.400 --> 0:09:57.000 we can observe the effect of say, of of this 0:09:57.080 --> 0:10:00.760 intense gravity on the surrounding environment. And despite the fact 0:10:00.760 --> 0:10:02.720 that we can't see inside them, as we'll talk about 0:10:02.720 --> 0:10:04.439 a couple of times as we go along, that doesn't 0:10:04.520 --> 0:10:07.760 necessarily mean we don't see anything around them. In fact, 0:10:07.880 --> 0:10:10.520 they can often put on quite a show. Yeah, I 0:10:10.800 --> 0:10:14.880 hate to lean into the horror movie implications here, but 0:10:14.880 --> 0:10:17.520 it's kind of like imagine the uh, the house from 0:10:17.520 --> 0:10:19.720 the Texas Chainsaw Mask. Here, you can't see any of 0:10:19.720 --> 0:10:22.679 the teenagers dying inside it from the outside, but you 0:10:22.720 --> 0:10:25.439 see them like moving towards the house. You see a 0:10:25.520 --> 0:10:29.480 lot of of random hippie activity on the outside, and 0:10:29.520 --> 0:10:31.079 it gives you an idea of what might be going 0:10:31.120 --> 0:10:33.560 on in the inside. Actually came up with an analogy 0:10:33.600 --> 0:10:35.560 I was going to use in the next episode, but 0:10:35.600 --> 0:10:37.760 maybe I'll go ahead and say it. So this is 0:10:37.760 --> 0:10:39.600 a little less grizzly than what you said, but kind 0:10:39.600 --> 0:10:43.400 of similar. So, uh, imagine you've got like a haunted 0:10:43.440 --> 0:10:46.600 house ride in an amusement park, and the ride, the 0:10:46.640 --> 0:10:48.600 part of the ride that you ride in is the 0:10:48.679 --> 0:10:51.360 soundproof box where nobody can hear anything on the outside. 0:10:51.360 --> 0:10:53.319 So you've got everybody in line to get in the ride, 0:10:53.320 --> 0:10:55.040 to get in the soundproof box and go through the 0:10:55.040 --> 0:11:00.000 haunted house. And as you're hurting tourists towards this soundproof box, 0:11:00.200 --> 0:11:02.480 even though you can't hear any of the screams inside 0:11:02.480 --> 0:11:05.000 the box, you will hear more and more sort of 0:11:05.640 --> 0:11:09.239 nervous chatter and laughter and shrieks as people are approaching 0:11:09.280 --> 0:11:12.120 the door, but then once you shut the door, bye bye. 0:11:12.679 --> 0:11:14.960 I like that we both independently came up with haunted 0:11:15.000 --> 0:11:18.960 house explanations for black holes. Personally, I seriously doubt that 0:11:19.000 --> 0:11:22.800 the Texas Chainsaw House is haunted or contains a black hole. Now, 0:11:22.880 --> 0:11:24.559 now it's important to note in all of this that 0:11:24.880 --> 0:11:26.600 I really think we should try and get away from 0:11:26.679 --> 0:11:30.800 thinking of black holes as essentially galactus or or some 0:11:30.880 --> 0:11:35.559 sort of other unstoppable, insatiable cosmic devour that just destroys 0:11:35.600 --> 0:11:38.880 and consumes everything, which is kind of hard because, as 0:11:38.880 --> 0:11:41.240 we've discussed before in the show, like that's a classic 0:11:41.360 --> 0:11:44.160 mythic trope, like the idea of some entity that will 0:11:44.240 --> 0:11:46.640 consume the Sun. I mean, it's key to these various 0:11:46.640 --> 0:11:50.760 eclipse mythologies that we've discussed in the past. But a 0:11:50.800 --> 0:11:54.280 black hole is not, uh, this thing is just going 0:11:54.360 --> 0:11:58.480 to eat the entire universe. They're bound by physics, so stars, planets, 0:11:58.480 --> 0:12:01.679 whole galaxies may orbit around them. And I've seen it 0:12:01.720 --> 0:12:05.000 pointed out before by NASA that if our Sun were 0:12:05.040 --> 0:12:08.000 a black hole of equal mass, the Earth would not 0:12:08.240 --> 0:12:11.760 fall in. Yeah, that's a point I've read many times before. 0:12:12.280 --> 0:12:14.400 So what would happen to the Earth if the Sun 0:12:14.480 --> 0:12:17.240 turned into a black hole? The Earth would keep orbiting. Yeah, 0:12:17.559 --> 0:12:20.120 So again, to come back to the Texas Chainsaw mascure House, 0:12:20.720 --> 0:12:23.120 it's it's not like the Texas Chainsaw Masscure House is 0:12:23.160 --> 0:12:26.120 just going to suck in everybody in the surrounding area 0:12:26.200 --> 0:12:28.760 and collapse the town. Now, the town continues to thrive. Yeah, 0:12:28.760 --> 0:12:30.520 the next door neighbors, they just keep going to work, 0:12:30.800 --> 0:12:33.520 they saying, keep selling barbecue. Everything's fine. And I also 0:12:33.559 --> 0:12:36.640 think again, the whole aspect of this is a stumbling 0:12:36.640 --> 0:12:39.160 block because it tends to encourage us to think of 0:12:39.320 --> 0:12:42.760 black holes less as what they presumably are and more 0:12:42.800 --> 0:12:46.040 like wormholes. Okay, so it's like it's like a tunnel 0:12:46.120 --> 0:12:50.280 you can go through. Yeah, yeah, But ultimately, a singularity 0:12:50.440 --> 0:12:53.600 is not a gateway. It doesn't go anywhere other than 0:12:53.679 --> 0:12:57.240 to the center of its gravity. Their celestial objects that 0:12:57.280 --> 0:13:00.400 just happened to be massive on a scale that's really 0:13:00.400 --> 0:13:03.440 harder to square with human experience. Well, I can tell already, 0:13:03.520 --> 0:13:06.480 Robert that you're running into issues with the language that 0:13:06.559 --> 0:13:10.160 we have to use to describe things, because there is 0:13:10.320 --> 0:13:14.440 no language, I mean, the only language we have is 0:13:14.520 --> 0:13:18.280 like normal terrestrial vocabulary, and then the metaphors we build 0:13:18.280 --> 0:13:23.040 out of that normal terrestrial vocabulary, so inevitably our language 0:13:23.080 --> 0:13:27.280 will ultimately fail to have words that, at a fundamental 0:13:27.360 --> 0:13:31.320 level really communicate the nature of celestial objects, you know, 0:13:31.360 --> 0:13:35.880 powerful objects, huge objects like black holes. So we we 0:13:35.960 --> 0:13:38.719 just have to use metaphors, right, and the idea of 0:13:38.720 --> 0:13:41.000 a black hole is a metaphor. Yeah, and it's it's 0:13:41.000 --> 0:13:43.800 a challenge for science communication for sure. A lot of 0:13:43.840 --> 0:13:46.920 great black hole studies come out, and then you look 0:13:46.960 --> 0:13:50.440 at the headlines that that are used right to to 0:13:50.520 --> 0:13:54.120 relate these findings, and it's it's I often get a 0:13:54.240 --> 0:13:57.160 laugh out of it because the world leader model is 0:13:57.200 --> 0:13:59.800 so often employed and you end up hearing reading about 0:14:00.040 --> 0:14:04.840 hannibal black holes, gobbling black holes, eating black holes, barfing 0:14:04.880 --> 0:14:08.440 black holes. Yeah, it's so anthropomorphised in a really visceral way. 0:14:08.440 --> 0:14:10.840 I mean you almost want to imagine that there are 0:14:10.920 --> 0:14:14.800 articles about dating black holes, swipe right black holes. But 0:14:14.840 --> 0:14:16.559 it's it's kind of a your damned if you do, 0:14:16.600 --> 0:14:18.320 your damned if you don't situation. It's kind of like 0:14:18.360 --> 0:14:22.760 when you when when we even anthropomorphize evolution to some extent, 0:14:23.200 --> 0:14:26.440 we treat it like a person, right, And I mean, 0:14:27.160 --> 0:14:29.960 on one hand, I acknowledge, yes, one should not do that. 0:14:30.000 --> 0:14:33.440 You fall into, you know, potential traps by doing it. 0:14:33.640 --> 0:14:36.280 But at the same time, you ultimately are trying to 0:14:37.360 --> 0:14:42.680 put some fairly complex ideas into a form that people 0:14:42.720 --> 0:14:45.880 can really consume. Well, you can talk about evolution without 0:14:45.880 --> 0:14:49.360 anthropomorphizing it or you know, treating it like a person 0:14:49.480 --> 0:14:52.120 with intentions. It's possible to do that. It can just 0:14:52.200 --> 0:14:55.720 get really tedious to constantly be talking that way. So 0:14:55.760 --> 0:14:58.880 we and we inevitably in these discussions, if we're just 0:14:58.920 --> 0:15:01.800 trying to move things long and you know, move at 0:15:01.800 --> 0:15:04.440 a brisk pace, we end up using the shorthand. And 0:15:04.480 --> 0:15:06.880 the same thing happens for black holes. Black holes, we 0:15:07.000 --> 0:15:11.040 end up using these colloquial shorthands to describe them that 0:15:11.080 --> 0:15:14.720 are based on Earth metaphors that don't really get at 0:15:14.760 --> 0:15:17.200 the truth of what it's like to have the geometry 0:15:17.200 --> 0:15:20.720 of space time warped by this gravitational anomaly. Now, one 0:15:20.720 --> 0:15:23.000 of the really fascinating things about black holes, though, is 0:15:23.040 --> 0:15:25.400 that we we simply we didn't simply look into the 0:15:25.440 --> 0:15:29.600 sky and observe them. Uh. It all began with the math. 0:15:29.720 --> 0:15:33.640 It began with with with some some very bright individuals 0:15:34.160 --> 0:15:38.040 crunching the numbers and seeing them as a possibility. Yeah, 0:15:38.080 --> 0:15:40.160 and that's one of the things that makes black holes 0:15:40.200 --> 0:15:44.040 so interesting. They weren't like stars. They weren't you know, stars. 0:15:44.080 --> 0:15:46.400 We could look up and know something was there, and 0:15:46.400 --> 0:15:50.360 then over time gradually make observations to refine our knowledge 0:15:50.400 --> 0:15:53.080 of what stars are. Right, black holes weren't like that. 0:15:53.120 --> 0:15:56.320 We had to work them out from first principles and 0:15:56.360 --> 0:15:59.360 then say, okay, is there a way we could observe them? 0:15:59.400 --> 0:16:02.480 It worked actually the opposite way. Yeah, that's the beautiful 0:16:02.520 --> 0:16:04.920 part we see because we see it paying off. We 0:16:04.920 --> 0:16:07.800 we we we we end up looking out into the 0:16:07.800 --> 0:16:11.520 cosmos and observing the very things that we have simulated 0:16:11.960 --> 0:16:15.600 with math and physics. The great astrophysicists Supermania and Chandra 0:16:15.680 --> 0:16:19.000 Sheker had in a prologue to his book The Mathematical 0:16:19.080 --> 0:16:22.440 Theory of black Holes, he wrote, quote, the black holes 0:16:22.480 --> 0:16:26.360 of nature are the most perfect macroscopic objects there are 0:16:26.480 --> 0:16:29.840 in the universe. The only elements in their construction are 0:16:29.840 --> 0:16:32.640 our concepts of space and time. All right, Well, on 0:16:32.680 --> 0:16:34.280 that note, we're gonna take a quick break, and when 0:16:34.280 --> 0:16:36.600 we come back. We are going to jump into the 0:16:36.680 --> 0:16:41.480 history of black holes. Thank you, thank alright, we're back. 0:16:41.880 --> 0:16:44.120 So previously we were just talking about how black holes 0:16:44.160 --> 0:16:47.240 began as an idea before they were observed in nature. 0:16:47.280 --> 0:16:50.560 They started as something that people worked out from principles 0:16:50.600 --> 0:16:53.800 they had established through other means, rather than something we 0:16:53.880 --> 0:16:57.200 looked up into the heavens and saw. And there's there's 0:16:57.200 --> 0:16:59.840 a really great book about this actually that I want 0:16:59.840 --> 0:17:02.240 to for two because it's one of the sources I 0:17:02.320 --> 0:17:04.320 used in working on this episode. But it's called black 0:17:04.320 --> 0:17:07.720 Hole by Marcia Bartoustiac, and it's a it's a book 0:17:07.760 --> 0:17:09.960 just about the history of the idea of the black hole, 0:17:10.000 --> 0:17:13.000 how it went from the idea of gravity to something 0:17:13.040 --> 0:17:17.440 that we now do experiments on with with cosmological detection equipment. 0:17:18.040 --> 0:17:20.120 So the story of the black hole can really be connected, 0:17:20.160 --> 0:17:24.480 I think, to the broader story of the discovery of gravity. Uh. 0:17:24.520 --> 0:17:27.640 You know, we often don't even bother to think anymore, 0:17:27.760 --> 0:17:31.000 why do objects fall down and not up? But I, oh, 0:17:31.160 --> 0:17:34.040 I sometimes wonder like do kids still have this thought? 0:17:34.359 --> 0:17:38.560 Do kids ask this sometimes or are they exposed to 0:17:38.640 --> 0:17:41.199 the theories we have of gravity before they even have 0:17:41.320 --> 0:17:44.320 the chance to ask that question naturally, you know, that's 0:17:44.400 --> 0:17:48.720 that's a great question, because I they certainly grasp the 0:17:48.840 --> 0:17:51.600 idea and the reality of gravity is just one of 0:17:51.640 --> 0:17:54.600 the realities of the natural world that they've evolved to 0:17:54.640 --> 0:17:56.840 thrive him. Of course we understand how it works, but 0:17:57.000 --> 0:18:00.040 why yeah, yeah, you know my own personal experience, I 0:18:00.040 --> 0:18:02.040 don't know that I've ever had a conversation with my 0:18:02.080 --> 0:18:05.800 son about gravity um or at least not when he 0:18:05.880 --> 0:18:09.240 was old enough to to appreciate it. I'm gonna have 0:18:09.280 --> 0:18:11.639 to make a mission of explaining it to him. But 0:18:11.840 --> 0:18:14.679 he also he may know already because he listens to 0:18:15.240 --> 0:18:18.000 to educational podcasts, so he when I mentioned black holes, 0:18:18.000 --> 0:18:20.000 he was like, oh, yeah, black holes. I was listening 0:18:20.040 --> 0:18:22.280 to a while in the world about black holes, so 0:18:22.480 --> 0:18:24.280 he already had a already had a leg up on 0:18:24.320 --> 0:18:26.160 the concept. Well, I mean, it's one of those things 0:18:26.240 --> 0:18:28.119 where most of us, I think, even people who are 0:18:28.160 --> 0:18:31.360 aware of general relativity, we sort of have the idea 0:18:31.480 --> 0:18:34.000 that we understand how gravity works, but then sit down 0:18:34.000 --> 0:18:36.760 and try to put into words like explain it, and 0:18:36.800 --> 0:18:40.400 then you start going, oh, wait a minute. But yeah, 0:18:40.440 --> 0:18:42.280 So it's one of those things that once you've heard 0:18:42.320 --> 0:18:44.159 it you think you've got to grasp on it, but 0:18:44.480 --> 0:18:47.760 even then it can prove tricky to try to explain yourself. 0:18:47.840 --> 0:18:51.160 But so you know, thousands or maybe millions of people 0:18:51.240 --> 0:18:53.600 must have stopped to wonder this all the time before 0:18:53.640 --> 0:18:55.680 we had a real answer why did things fall down 0:18:55.720 --> 0:18:57.960 instead of up? And for a long time I think 0:18:58.000 --> 0:19:03.400 humans were led astray by this intuitive, false cosmology of geocentrism. 0:19:03.440 --> 0:19:06.399 So if you believe, like Aristotle, that the Earth is 0:19:06.440 --> 0:19:08.760 the center of the universe, it makes a kind of 0:19:08.800 --> 0:19:12.440 intuitive sense that everything would fall toward the center, right 0:19:13.200 --> 0:19:15.239 And then again I sometimes wonder, like, why is that 0:19:15.320 --> 0:19:18.040 even intuitive? Why doesn't everything fall away from the center 0:19:18.040 --> 0:19:20.639 out to the edges. It just feels right enough that 0:19:20.720 --> 0:19:23.679 you can stop thinking about the question basically. But then 0:19:23.720 --> 0:19:26.680 once you introduce the Copernican model, the you know, the 0:19:26.680 --> 0:19:29.760 heliocentric model of the Solar system, and the idea that 0:19:29.800 --> 0:19:31.960 the Earth is not the center of the universe and 0:19:32.000 --> 0:19:34.920 in fact is no kind of privileged place at all. 0:19:34.920 --> 0:19:38.600 It's just another object floating around in space, Suddenly we 0:19:38.720 --> 0:19:41.760 really need an explanation for why objects fall to the 0:19:41.800 --> 0:19:44.639 ground rather than fly off in the opposite direction. And 0:19:44.680 --> 0:19:48.240 the bigger question. Is the force that causes objects to 0:19:48.280 --> 0:19:51.480 fall to the ground the same force that guides planets 0:19:51.480 --> 0:19:54.040 in their orbits around the Sun. I like what you 0:19:54.040 --> 0:19:57.560 said about the geocentric view because I think the geocentric 0:19:57.640 --> 0:20:01.040 view also kind of lines up with our aasic egoic 0:20:01.440 --> 0:20:04.600 experience of the world, Like everything in the world ultimately 0:20:04.600 --> 0:20:07.760 breaks down to what I feel about it, because I 0:20:07.800 --> 0:20:11.359 am the only the only experience, the only worldview you 0:20:11.359 --> 0:20:14.760 know that I that I have control of and one 0:20:15.160 --> 0:20:19.040 percent vision through. And uh. But then if someone would say, actually, 0:20:19.080 --> 0:20:21.000 you're not the most important person in the world. Is 0:20:21.359 --> 0:20:24.120 uh this person over here is that throws everything out 0:20:24.160 --> 0:20:26.480 of out of whack. Well, it makes you realize that 0:20:26.520 --> 0:20:30.120 your egoic view is not even necessarily a coherent view, 0:20:30.280 --> 0:20:32.399 is just something that you can do without having to 0:20:32.400 --> 0:20:35.399 think about. And I would argue the same is largely 0:20:35.440 --> 0:20:39.359 true for geocentric physics. Uh though actually, in a funny way, 0:20:39.400 --> 0:20:42.760 a lot of really intense thinking did go into constructing 0:20:42.760 --> 0:20:46.919 geocentric cosmologies and they look kind of beautiful. But anyway, 0:20:46.920 --> 0:20:50.119 coming back to gravity, so so we know that for example, 0:20:50.240 --> 0:20:54.719 Johannes Kepler suggested that the sun exerted a magnetic force 0:20:54.920 --> 0:20:58.440 that guided the orbits of the planets. Weird to think 0:20:58.480 --> 0:21:01.080 back to a time when they were thinking, Okay, how 0:21:01.080 --> 0:21:04.440 are the planets controlled in there? Or maybe it's magnetism. 0:21:04.440 --> 0:21:07.640 We know magnets exist, that's an attractive force. Maybe that's 0:21:07.680 --> 0:21:11.480 what controls it. And in the sixteen thirties, Descartes proposed 0:21:11.520 --> 0:21:14.399 that the orbits of the planets were guided by swirlings 0:21:14.400 --> 0:21:17.240 in the ether, which was this substance that was believed 0:21:17.280 --> 0:21:19.359 to occupy space. The ether would have been kind of 0:21:19.400 --> 0:21:22.960 like air water, this fluid that occupied empty space, and 0:21:23.000 --> 0:21:27.080 you could have whirlpools or cyclones guiding objects in a 0:21:27.119 --> 0:21:30.000 circular pattern around a center of motion, and that would 0:21:30.000 --> 0:21:32.360 be what would guide orbits in the ether. But then, 0:21:32.400 --> 0:21:34.800