1 00:00:01,280 --> 00:00:03,320 Speaker 1: Hey, it Jorhan Daniel here, and we want to tell 2 00:00:03,360 --> 00:00:06,880 Speaker 1: you about our new book. It's called Frequently Asked Questions 3 00:00:06,960 --> 00:00:09,719 Speaker 1: about the Universe because you have questions about the universe, 4 00:00:09,800 --> 00:00:12,399 Speaker 1: and so we decided to write a book all about them. 5 00:00:12,400 --> 00:00:14,800 Speaker 1: We talk about your questions, we give some answers, we 6 00:00:14,880 --> 00:00:17,520 Speaker 1: make a bunch of silly jokes as usual, and we 7 00:00:17,600 --> 00:00:20,159 Speaker 1: tackle all kinds of questions, including what happens if I 8 00:00:20,200 --> 00:00:22,880 Speaker 1: fall into a black hole? Or is there another version 9 00:00:22,920 --> 00:00:25,480 Speaker 1: of you out there that's right? Like usual, we tackle 10 00:00:25,600 --> 00:00:29,960 Speaker 1: the deepest, darkest, biggest, craziest questions about this incredible cosmos. 11 00:00:29,960 --> 00:00:31,800 Speaker 1: If you want to support the podcast, please get the 12 00:00:31,800 --> 00:00:33,879 Speaker 1: book and get a copy not just for yourself, but 13 00:00:34,120 --> 00:00:39,360 Speaker 1: you know, for your nieces and nephews, cousins, friends, parents, dogs, hamsters, 14 00:00:39,400 --> 00:00:42,640 Speaker 1: and for the aliens. So get your copy of Frequently 15 00:00:42,720 --> 00:00:46,440 Speaker 1: Asked Questions about the Universe is available for pre order now, 16 00:00:46,520 --> 00:00:49,239 Speaker 1: coming out November two. You can find more details at 17 00:00:49,240 --> 00:00:53,160 Speaker 1: the book's website, Universe f a Q dot com. Thanks 18 00:00:53,159 --> 00:00:55,000 Speaker 1: for your support, and if you have a hamster that 19 00:00:55,040 --> 00:00:57,240 Speaker 1: can read, please let us know. We'd love to have 20 00:00:57,320 --> 00:01:10,720 Speaker 1: them on the podcast. Hey Daniel, how do you know 21 00:01:10,760 --> 00:01:14,400 Speaker 1: that an electron is actually an electron? What do you mean? 22 00:01:14,440 --> 00:01:16,480 Speaker 1: I mean, what else could it be? Well, what do 23 00:01:16,520 --> 00:01:19,760 Speaker 1: you really know about an electron? Well, that's a good question. 24 00:01:19,840 --> 00:01:22,319 Speaker 1: I mean, you can measure things about it, like it's mass, 25 00:01:22,440 --> 00:01:26,160 Speaker 1: and it's charge and it's spin. So even if you can, 26 00:01:26,440 --> 00:01:29,000 Speaker 1: you know, look at it directly, that's enough to tell 27 00:01:29,000 --> 00:01:31,600 Speaker 1: you that it's an electron. I guess. So, I mean 28 00:01:31,640 --> 00:01:33,960 Speaker 1: if it quacks like an electron and it walks like 29 00:01:34,000 --> 00:01:38,440 Speaker 1: an electron, then you call an electron a doctron. But 30 00:01:38,480 --> 00:01:39,880 Speaker 1: I guess you know, how do you know there isn't 31 00:01:39,920 --> 00:01:43,600 Speaker 1: another particle with like the same charge and mass and spin, 32 00:01:43,920 --> 00:01:47,720 Speaker 1: but is not an electron like another particle hiding and 33 00:01:47,800 --> 00:01:52,560 Speaker 1: electron clothing. Yeah, like the incocniton or the full electron, 34 00:01:53,040 --> 00:01:56,600 Speaker 1: or the non electron or the electron. Not. Well, I'm 35 00:01:56,640 --> 00:01:58,200 Speaker 1: glad we have a name for it, even if we 36 00:01:58,240 --> 00:02:16,120 Speaker 1: haven't discovered it yet. I am or Hammer cartoonists and 37 00:02:16,120 --> 00:02:18,880 Speaker 1: the creator of PhD comics. Hi, I'm Daniel. I'm a 38 00:02:18,919 --> 00:02:21,240 Speaker 1: part of Gold physicist or at least I walk like 39 00:02:21,320 --> 00:02:24,320 Speaker 1: one and I quack like one. Oh really, physicists quack 40 00:02:24,520 --> 00:02:26,720 Speaker 1: that a thing you do when you discover something amazing 41 00:02:26,760 --> 00:02:29,119 Speaker 1: about the universe. Oh yeah, we quack about corks all 42 00:02:29,120 --> 00:02:33,600 Speaker 1: the time and quasars. Yeah, I guess regular nerds a 43 00:02:33,680 --> 00:02:37,360 Speaker 1: snort and when they laugh and we're get excited. Physicists 44 00:02:37,440 --> 00:02:40,360 Speaker 1: are hardcore and you quack, yeah exactly, don't quibble about 45 00:02:40,360 --> 00:02:42,040 Speaker 1: the way we quack. And that's why you fly south 46 00:02:42,080 --> 00:02:46,400 Speaker 1: every winter, right, that's why I live in south southern California. 47 00:02:46,760 --> 00:02:49,400 Speaker 1: Sabbaticals in the South Pacific. No, i' made a mistake. 48 00:02:49,440 --> 00:02:51,600 Speaker 1: I took my sabbatical by going north. I went to 49 00:02:51,680 --> 00:02:54,680 Speaker 1: Copenhagen briefly, but you went in the summer though, right, 50 00:02:55,400 --> 00:02:58,560 Speaker 1: days were long, Right exactly, it's the right place to 51 00:02:58,560 --> 00:03:01,240 Speaker 1: go in the summer. This is one smart duck. But anyways, 52 00:03:01,240 --> 00:03:03,840 Speaker 1: welcome to our podcast, Daniel and Jorge Explain the Universe, 53 00:03:03,880 --> 00:03:06,160 Speaker 1: a production of I Art Radio, in which we fly 54 00:03:06,360 --> 00:03:09,120 Speaker 1: north and we fly south, we go on sabbatical, and 55 00:03:09,120 --> 00:03:12,680 Speaker 1: we engage our brains in the big questions of the universe. 56 00:03:12,880 --> 00:03:16,600 Speaker 1: We try to ask the biggest, deepest, darkest, craziest questions 57 00:03:16,600 --> 00:03:19,079 Speaker 1: about the nature of the universe, what's in it, what's 58 00:03:19,120 --> 00:03:22,000 Speaker 1: out there, and what it really means? Is the reality 59 00:03:22,040 --> 00:03:24,919 Speaker 1: we see around us, the reality that's actually out there 60 00:03:25,000 --> 00:03:28,480 Speaker 1: independent of human thought, or is it vastly different than 61 00:03:28,480 --> 00:03:31,799 Speaker 1: our crazy, tiny human brains can't imagine? Is the worldlined 62 00:03:31,919 --> 00:03:34,200 Speaker 1: us and hiding and pretending to be something that it 63 00:03:34,240 --> 00:03:36,800 Speaker 1: isn't or is it just the way it looks? Yeah, 64 00:03:36,840 --> 00:03:39,160 Speaker 1: because it is a pretty tricky universe. You know, it's 65 00:03:39,160 --> 00:03:42,720 Speaker 1: not only big and almost a hidden from us because 66 00:03:42,720 --> 00:03:45,000 Speaker 1: it's so large, but there's also, you know, kind of 67 00:03:45,000 --> 00:03:47,240 Speaker 1: strange things about it, because you know, the only things 68 00:03:47,280 --> 00:03:49,120 Speaker 1: that we know about the universe are the things we 69 00:03:49,160 --> 00:03:53,040 Speaker 1: can see or at least measure with our instruments, and sometimes, 70 00:03:53,160 --> 00:03:55,440 Speaker 1: you know, the universe places tricks on us. Yeah, and 71 00:03:55,440 --> 00:03:58,720 Speaker 1: you can ask really fun, interesting philosophical questions, like how 72 00:03:58,720 --> 00:04:00,760 Speaker 1: do you know what some thing is? Like you eat 73 00:04:00,760 --> 00:04:02,560 Speaker 1: an ice cream cone? You know, it feels like an 74 00:04:02,600 --> 00:04:04,440 Speaker 1: ice cream cone in your hand, it tastes like an 75 00:04:04,440 --> 00:04:06,920 Speaker 1: ice cream cone. How do you know it's not actually 76 00:04:06,920 --> 00:04:09,520 Speaker 1: something else and you're being fooled and it tastes like 77 00:04:09,560 --> 00:04:12,240 Speaker 1: an ice cream cone, but it's actually something crazy and weird, 78 00:04:12,320 --> 00:04:15,720 Speaker 1: like an assembly of nanobots that's been collected to like 79 00:04:15,800 --> 00:04:19,120 Speaker 1: invade your body and taste like ice cream. Oh, my gosh, 80 00:04:19,320 --> 00:04:23,000 Speaker 1: you just give me nightmares about eating ice cream. I 81 00:04:23,000 --> 00:04:25,280 Speaker 1: hope I didn't just ruin ice cream for everybody you 82 00:04:25,400 --> 00:04:28,000 Speaker 1: might have. Yeah, No, I'm gonna worry eating nanobots or 83 00:04:28,040 --> 00:04:31,000 Speaker 1: something evil nanobots fooling my tongue. There is a deep 84 00:04:31,040 --> 00:04:33,400 Speaker 1: question there because we are limited in the ways that 85 00:04:33,440 --> 00:04:36,920 Speaker 1: we interact with the universe, right, We can't see the absolute, ultimate, 86 00:04:37,000 --> 00:04:39,880 Speaker 1: complete truth of the universe. Ever. We have these narrow 87 00:04:39,960 --> 00:04:42,640 Speaker 1: little ways. We can see, we can taste, we can touch, 88 00:04:42,960 --> 00:04:45,520 Speaker 1: we can smell, and that paints a picture in our 89 00:04:45,560 --> 00:04:47,919 Speaker 1: minds of what we think the universe is like. But 90 00:04:48,000 --> 00:04:50,560 Speaker 1: it's a very narrow way to interact with the universe, 91 00:04:50,560 --> 00:04:53,240 Speaker 1: and it is possible that we are confused about what's 92 00:04:53,320 --> 00:04:56,000 Speaker 1: actually out there. Yeah, because I guess the universe is 93 00:04:56,040 --> 00:04:59,479 Speaker 1: tricky like that, And I mean it's so complex. That's 94 00:04:59,520 --> 00:05:02,040 Speaker 1: something that it seem like, you know, ice cream could 95 00:05:02,040 --> 00:05:04,040 Speaker 1: be something else. You know, it could have fake sugar 96 00:05:04,279 --> 00:05:09,040 Speaker 1: or nana bots or artificial flavors, you know, or artificial 97 00:05:09,120 --> 00:05:11,080 Speaker 1: nana bouts, Like, hey, I ordered nano bots of my 98 00:05:11,120 --> 00:05:13,560 Speaker 1: ice cream. These aren't real nano bots. Now, I can't 99 00:05:13,560 --> 00:05:16,200 Speaker 1: even trust the nana bouts They could be you know, 100 00:05:16,400 --> 00:05:18,560 Speaker 1: the cheap kind or something. That's right, they kind of 101 00:05:18,560 --> 00:05:20,479 Speaker 1: give you indigestion later, you don't want to eat those. 102 00:05:20,560 --> 00:05:23,320 Speaker 1: It could be po bots or fempty bots. Well, I 103 00:05:23,320 --> 00:05:25,680 Speaker 1: paid for Nana bots and I just got these Milli bots. Man, 104 00:05:25,720 --> 00:05:28,400 Speaker 1: I can even see these with my eyeballs. What's going on? 105 00:05:28,880 --> 00:05:31,800 Speaker 1: They're too crunchy. Yeah, they ruined the texture of your 106 00:05:32,279 --> 00:05:34,760 Speaker 1: fake ice cream. But mostly we're not that worried about 107 00:05:34,760 --> 00:05:36,800 Speaker 1: ice cream. As long as it tastes good, it's fine. 108 00:05:37,080 --> 00:05:39,960 Speaker 1: Mostly we're worried about the nature of the universe and 109 00:05:40,000 --> 00:05:42,880 Speaker 1: what's in it, what's out there in the universe. Yeah, 110 00:05:42,880 --> 00:05:45,039 Speaker 1: and one of the most interesting things out there for 111 00:05:45,120 --> 00:05:48,080 Speaker 1: people to study are black holes. It seems like we 112 00:05:48,120 --> 00:05:51,200 Speaker 1: get a question about black holes almost every week on 113 00:05:51,240 --> 00:05:53,919 Speaker 1: the podcast, right, Yeah, this should basically become a black 114 00:05:53,920 --> 00:05:57,359 Speaker 1: hole podcast. We're basically just falling into the gravitational attraction 115 00:05:57,480 --> 00:05:59,760 Speaker 1: of the mysteries of black holes. Yeah. I guess the 116 00:05:59,839 --> 00:06:03,320 Speaker 1: r very attractive and deep. Yeah, and once you start 117 00:06:03,360 --> 00:06:05,840 Speaker 1: talking about them, you basically can't escape. There's like a 118 00:06:05,920 --> 00:06:09,960 Speaker 1: question horizon or something. Yeah, it's a massive topic. But 119 00:06:10,120 --> 00:06:13,159 Speaker 1: even black holes, as you know, as much as we 120 00:06:13,200 --> 00:06:15,000 Speaker 1: know about them, Like, we know they're there. You can 121 00:06:15,000 --> 00:06:17,920 Speaker 1: see them gravitationally. And now recently, in the last year 122 00:06:18,000 --> 00:06:21,440 Speaker 1: or two, we've actually gotten pictures of black holes. Right, Yeah, 123 00:06:21,480 --> 00:06:23,800 Speaker 1: we have a lot of information about black holes, and 124 00:06:23,839 --> 00:06:26,400 Speaker 1: you just said we know that they are there, And 125 00:06:26,440 --> 00:06:29,360 Speaker 1: that's a really interesting question. Like, we know a lot 126 00:06:29,400 --> 00:06:31,599 Speaker 1: of things about black holes. We've measured a lot of 127 00:06:31,600 --> 00:06:33,479 Speaker 1: things about black holes. A lot of things that we 128 00:06:33,520 --> 00:06:36,320 Speaker 1: see makes sense a black holes were there. But you know, 129 00:06:36,600 --> 00:06:39,080 Speaker 1: how do we really know it's not just a bunch 130 00:06:39,080 --> 00:06:42,080 Speaker 1: of nanobots out there fooling us in deep space? Oh? Man, 131 00:06:42,640 --> 00:06:44,480 Speaker 1: I imagine we're not going to be licking the black 132 00:06:44,480 --> 00:06:47,479 Speaker 1: holes or eating them, hopefully not. I don't think anybody 133 00:06:47,520 --> 00:06:50,120 Speaker 1: ever said licking the black hole until you just said it. 134 00:06:50,320 --> 00:06:52,720 Speaker 1: Then it's the first time in human history anybody ever 135 00:06:52,760 --> 00:06:54,800 Speaker 1: said that. We'll trade that and put it on our 136 00:06:54,839 --> 00:06:57,960 Speaker 1: T shirts. Daniel and Horror explain the universe liking the 137 00:06:58,040 --> 00:07:01,400 Speaker 1: black holes. That's like a pitch for the science fiction 138 00:07:01,520 --> 00:07:05,559 Speaker 1: version of a Christmas story. Yeah, you're going to shoot 139 00:07:05,560 --> 00:07:09,720 Speaker 1: your eye out and or well into a singularity forever. Alright, 140 00:07:09,760 --> 00:07:12,360 Speaker 1: we're talking about black holes today and this sort of 141 00:07:12,440 --> 00:07:16,280 Speaker 1: philosophical question almost about the true nature of black holes 142 00:07:16,320 --> 00:07:18,600 Speaker 1: and whether or not we are actually looking at or 143 00:07:18,680 --> 00:07:21,960 Speaker 1: feeling black holes. Yeah, what's actually out there that's giving 144 00:07:22,040 --> 00:07:25,360 Speaker 1: us the impression that black holes exist? And could it 145 00:07:25,480 --> 00:07:30,280 Speaker 1: be something else masquerading as a black hole? Oh man, sneaky. 146 00:07:30,480 --> 00:07:32,840 Speaker 1: So today on the program, we'll be tackling the question 147 00:07:37,880 --> 00:07:42,080 Speaker 1: what if black holes are not actually black holes? And Daniel, 148 00:07:42,080 --> 00:07:45,200 Speaker 1: are we questioning you know that they're not actually black 149 00:07:45,280 --> 00:07:48,560 Speaker 1: the color black, or that they're not actually holes or 150 00:07:48,640 --> 00:07:52,400 Speaker 1: both both and everything? We're questioning everything today, we're blowing 151 00:07:52,440 --> 00:07:55,360 Speaker 1: it all up. No, we are wondering what we actually 152 00:07:55,400 --> 00:07:57,600 Speaker 1: know about the nature of black holes. What evidence do 153 00:07:57,640 --> 00:08:01,600 Speaker 1: we have that they are this we your conceptual object 154 00:08:01,640 --> 00:08:04,720 Speaker 1: that really just exists in our minds and existed only 155 00:08:04,760 --> 00:08:07,520 Speaker 1: in the minds of physicists for fifty years before we 156 00:08:07,560 --> 00:08:10,040 Speaker 1: discovered them. Well, actually, I guess maybe they existed in 157 00:08:10,080 --> 00:08:12,760 Speaker 1: the universe before that, but the idea is only fifty 158 00:08:12,840 --> 00:08:14,880 Speaker 1: or so years old, and so we're asking the question, 159 00:08:14,920 --> 00:08:18,760 Speaker 1: is what's actually out there consistent with what's in our mind? Yeah, 160 00:08:18,760 --> 00:08:20,520 Speaker 1: Because I think black holes have had sort of an 161 00:08:20,520 --> 00:08:24,000 Speaker 1: interesting journey, right, Like first week thought up of them 162 00:08:24,040 --> 00:08:26,360 Speaker 1: as an imaginary thing, like we saw the theory and 163 00:08:26,400 --> 00:08:28,840 Speaker 1: we imagine that they could exist, and then we sort 164 00:08:28,840 --> 00:08:32,120 Speaker 1: of confirmed that they're there but not actually seeing them. 165 00:08:32,400 --> 00:08:35,959 Speaker 1: They sort of looked like they were there gravitationally, and 166 00:08:36,000 --> 00:08:39,400 Speaker 1: then more recently we've actually seen them. We have pictures 167 00:08:39,400 --> 00:08:42,400 Speaker 1: of them. But now we're asking the question here today, 168 00:08:42,840 --> 00:08:45,240 Speaker 1: are they really actually black holes? The things that we're 169 00:08:45,240 --> 00:08:47,960 Speaker 1: seeing in feeling? Yeah, because can you really see something 170 00:08:48,000 --> 00:08:50,640 Speaker 1: that's just black? You know, it's like sort of not 171 00:08:50,760 --> 00:08:53,640 Speaker 1: seeing it is seeing it. You know, we didn't see 172 00:08:53,800 --> 00:08:55,960 Speaker 1: light from the black hole, which would have told us 173 00:08:56,000 --> 00:08:59,000 Speaker 1: it's not a black hole. What we saw is not light, 174 00:08:59,160 --> 00:09:01,480 Speaker 1: which is not the same thing is seeing the black hole. 175 00:09:01,960 --> 00:09:05,000 Speaker 1: We didn't see the not black hole, or we saw 176 00:09:05,080 --> 00:09:07,120 Speaker 1: the not black hole we didn't. I don't know. I'm 177 00:09:07,160 --> 00:09:10,720 Speaker 1: confusing myself. Did it not see a not black hole 178 00:09:10,800 --> 00:09:13,520 Speaker 1: that is not actually there? Let's just keep going in 179 00:09:13,840 --> 00:09:16,640 Speaker 1: exactly consistent with the black hole prediction. We didn't see 180 00:09:16,679 --> 00:09:20,160 Speaker 1: photons from it. What does that actually proved? Right? Right? 181 00:09:20,280 --> 00:09:22,360 Speaker 1: If it looks like a triple negative and it walks 182 00:09:22,360 --> 00:09:25,800 Speaker 1: like a triple negative, it's actually true. Maybe I don't 183 00:09:25,800 --> 00:09:27,960 Speaker 1: know these philosophical jokes are too much for me. But 184 00:09:28,000 --> 00:09:29,800 Speaker 1: I guess if a black hole is not actually a 185 00:09:29,800 --> 00:09:32,080 Speaker 1: black hole, what else could it be? Yeah, and so 186 00:09:32,160 --> 00:09:36,000 Speaker 1: there are a bunch of other ideas for what could 187 00:09:36,120 --> 00:09:38,959 Speaker 1: maybe be masquerading as a black hole. What out there 188 00:09:39,000 --> 00:09:42,560 Speaker 1: in the universe, other theoretical concepts for what could give 189 00:09:42,679 --> 00:09:45,680 Speaker 1: us the same sort of set of observed data that 190 00:09:45,720 --> 00:09:48,320 Speaker 1: could give us the same experience without actually being a 191 00:09:48,400 --> 00:09:50,640 Speaker 1: black hole. Interesting? Do we have a name for these 192 00:09:50,840 --> 00:09:55,439 Speaker 1: mysterious fake full black holes or black holes? We do? 193 00:09:55,600 --> 00:09:59,240 Speaker 1: And this is this call these things dark stars, which 194 00:09:59,320 --> 00:10:01,400 Speaker 1: is how sort of cool in science fiction? E. It 195 00:10:01,440 --> 00:10:05,040 Speaker 1: does sound like another Marvel superhero or villain. I think, 196 00:10:05,040 --> 00:10:08,440 Speaker 1: actually that is maybe a d C hero, thinking we'll 197 00:10:08,440 --> 00:10:10,320 Speaker 1: have to google it. It sounds to me like the 198 00:10:10,400 --> 00:10:14,120 Speaker 1: jet black version of the Death Star. Interesting, that's for 199 00:10:14,200 --> 00:10:17,200 Speaker 1: the next Star Wars equal when there's another death Star 200 00:10:17,360 --> 00:10:20,560 Speaker 1: like the fourth one, but actually bigger and darker. Is 201 00:10:20,559 --> 00:10:22,280 Speaker 1: that what you're saying? Yeah, well, you know in Star 202 00:10:22,320 --> 00:10:24,520 Speaker 1: Wars they're always saying that's not a moon, that's a 203 00:10:24,559 --> 00:10:27,080 Speaker 1: space station, and this one they'll say, that's not a 204 00:10:27,120 --> 00:10:30,360 Speaker 1: black hole, that's a dark star space station. Oh my, 205 00:10:30,559 --> 00:10:34,640 Speaker 1: gosh called j J Abams. I'm sure he's a listener, 206 00:10:34,760 --> 00:10:38,560 Speaker 1: So j J you call us, that's right, you have 207 00:10:38,640 --> 00:10:42,080 Speaker 1: Daniel's email for waiting. So a dark star. So that's 208 00:10:42,160 --> 00:10:44,280 Speaker 1: kind of what we'll be talking about today, is that, 209 00:10:44,360 --> 00:10:46,440 Speaker 1: you know, maybe black holes are not black holes. Maybe 210 00:10:46,480 --> 00:10:50,280 Speaker 1: there's something called a dark stars. Yeah, exactly. These are fun, 211 00:10:50,360 --> 00:10:53,480 Speaker 1: crazy concepts that might be real out there in the universe. 212 00:10:53,760 --> 00:10:56,080 Speaker 1: So as usual, we were wondering how many people out 213 00:10:56,120 --> 00:10:59,600 Speaker 1: there had thought about the trueness of black holes and 214 00:10:59,720 --> 00:11:03,240 Speaker 1: had heard of these things called dark stars. So Daniel 215 00:11:03,280 --> 00:11:05,640 Speaker 1: went out there and ask people on the internet what 216 00:11:06,000 --> 00:11:08,400 Speaker 1: is a dark star? And if you are out there 217 00:11:08,400 --> 00:11:11,440 Speaker 1: in the Internet and still don't feel safe venturing outside 218 00:11:11,440 --> 00:11:14,120 Speaker 1: and talking to humans in person, I get it. And 219 00:11:14,200 --> 00:11:17,600 Speaker 1: so if you'd like to participate in these questions online 220 00:11:17,600 --> 00:11:19,880 Speaker 1: please they'll be shy and right to us two questions 221 00:11:19,920 --> 00:11:22,880 Speaker 1: at Daniel and Jorge dot com. We'd love to hear 222 00:11:22,880 --> 00:11:24,959 Speaker 1: your voice on the podcast. So think about it for 223 00:11:25,000 --> 00:11:27,480 Speaker 1: a second. If I say the words dark star, what 224 00:11:27,679 --> 00:11:30,440 Speaker 1: comes to your mind? It was what people had to say. 225 00:11:30,679 --> 00:11:34,320 Speaker 1: I think a dark star is a white dwarf that 226 00:11:34,440 --> 00:11:40,840 Speaker 1: has sufficiently cooled to become a black dwarf and doesn't 227 00:11:40,920 --> 00:11:44,280 Speaker 1: emit any radiation. Sounds like it's one that would not 228 00:11:44,520 --> 00:11:49,160 Speaker 1: emit any light, but maybe it's still emits radiation. Why 229 00:11:49,280 --> 00:11:52,120 Speaker 1: that would be, I have no idea, but that's my guess. 230 00:11:52,520 --> 00:11:56,760 Speaker 1: So I think I've heard of this where like say 231 00:11:56,800 --> 00:12:00,800 Speaker 1: a brown dwarf, a brown dwarf is niclear a star, 232 00:12:00,960 --> 00:12:04,679 Speaker 1: but it's a lot gammer and a lot cooler, and 233 00:12:05,520 --> 00:12:09,040 Speaker 1: typically a lot smaller. So that would be what I 234 00:12:09,080 --> 00:12:13,120 Speaker 1: would think a dark star is. White dwarfs are going 235 00:12:13,160 --> 00:12:16,560 Speaker 1: to burn out and become dark. It could also be 236 00:12:16,720 --> 00:12:20,720 Speaker 1: you guys thinking about dark matter somehow forming a star, 237 00:12:20,920 --> 00:12:24,400 Speaker 1: but the dark matter cannot interact with itself, so does 238 00:12:24,400 --> 00:12:28,319 Speaker 1: that work. At the beginning, I thought this dark star 239 00:12:28,360 --> 00:12:36,480 Speaker 1: was black hole, but lately I read that dark star 240 00:12:36,640 --> 00:12:38,840 Speaker 1: might be a type of star from the beginning of 241 00:12:38,840 --> 00:12:45,000 Speaker 1: the universe, really really big star, much bigger than battle 242 00:12:45,120 --> 00:12:49,320 Speaker 1: Juice or any other type of star that we've seen 243 00:12:49,679 --> 00:12:56,120 Speaker 1: until now. So this is from the really beginning of 244 00:12:56,160 --> 00:12:58,360 Speaker 1: the universe. If I say to you, what is the 245 00:12:58,440 --> 00:13:02,080 Speaker 1: dark star, what would you think? Well? Probably it could 246 00:13:02,080 --> 00:13:05,800 Speaker 1: also me and not very bright stars, and mostly there 247 00:13:05,840 --> 00:13:11,040 Speaker 1: are rampwarfs like Barnold Star are proxima centauri. All those 248 00:13:11,120 --> 00:13:16,240 Speaker 1: dark not very dark, does not be bright. A dark 249 00:13:16,280 --> 00:13:19,640 Speaker 1: star also awesome name for a band or opening cover 250 00:13:19,920 --> 00:13:23,040 Speaker 1: of a band. Dark star definitely, I'm going to go 251 00:13:23,120 --> 00:13:25,640 Speaker 1: with the dark matter star, even though dude, I have 252 00:13:25,760 --> 00:13:27,800 Speaker 1: no idea how such a thing could exists, because what 253 00:13:27,840 --> 00:13:30,160 Speaker 1: even is dark matter? No one knows. But if it 254 00:13:30,200 --> 00:13:34,320 Speaker 1: could clump and immage energy in the form of dark radiation, well, 255 00:13:34,559 --> 00:13:37,120 Speaker 1: even better band name. Then you will get a dark star. 256 00:13:37,920 --> 00:13:41,920 Speaker 1: I think a dark star is probably maybe a theoretical 257 00:13:42,000 --> 00:13:44,560 Speaker 1: object in dark matter, So maybe it's a star made 258 00:13:44,720 --> 00:13:47,520 Speaker 1: entirely of dark matter, but I'm not arrely sure. I 259 00:13:47,600 --> 00:13:50,880 Speaker 1: guess a dark star would be the star that's not 260 00:13:50,960 --> 00:13:57,439 Speaker 1: emitting light, so maybe a star that has already undergone 261 00:13:57,440 --> 00:14:01,920 Speaker 1: a supernova or that has collapsed into a black hole 262 00:14:02,120 --> 00:14:07,760 Speaker 1: or something otherwise. Um, I guess a rock star that 263 00:14:08,200 --> 00:14:12,360 Speaker 1: trash is hotel rooms would also be a dark star. Right. 264 00:14:13,000 --> 00:14:15,720 Speaker 1: Interesting answers here. I feel like all of these answers 265 00:14:15,760 --> 00:14:19,440 Speaker 1: could be a theory of physics in itself. There are 266 00:14:19,560 --> 00:14:22,280 Speaker 1: some great answers, and you hear some real knowledge in there. 267 00:14:22,280 --> 00:14:25,760 Speaker 1: There are people talking about dark matter stars or black dwarves. 268 00:14:25,960 --> 00:14:28,880 Speaker 1: Black dwarves are a real thing, are they? They absolutely are. 269 00:14:28,920 --> 00:14:31,320 Speaker 1: There are when a white dwarf, which is just a 270 00:14:31,440 --> 00:14:34,680 Speaker 1: huge hunk of hot metal no longer actually fusing and 271 00:14:34,720 --> 00:14:37,080 Speaker 1: giving off light, just sort of like glowing in the universe, 272 00:14:37,440 --> 00:14:41,160 Speaker 1: when they cool down eventually and stop glowing and become dark, 273 00:14:41,280 --> 00:14:43,640 Speaker 1: and so that's a black dwarf. I like this suggestion 274 00:14:43,680 --> 00:14:45,960 Speaker 1: that maybe it's like a dark matter star, which we 275 00:14:46,000 --> 00:14:48,120 Speaker 1: actually talked about on the podcast, right, Yeah, we did 276 00:14:48,160 --> 00:14:50,520 Speaker 1: talk about whether you can make dark matter stars and 277 00:14:50,600 --> 00:14:53,720 Speaker 1: maybe whether they would make dark photons using dark fusion 278 00:14:53,840 --> 00:14:55,960 Speaker 1: or something crazy like that. So if you're interested in 279 00:14:56,080 --> 00:14:58,720 Speaker 1: dark matter stars, go check out that whole episode. I see, 280 00:14:58,720 --> 00:15:01,480 Speaker 1: but that's its separate rock band, right, There's a Dark 281 00:15:01,520 --> 00:15:04,000 Speaker 1: Star and there's Dark Matter Star. Yeah. I think they 282 00:15:04,040 --> 00:15:06,120 Speaker 1: toured together once in the eighties, but it didn't go 283 00:15:06,200 --> 00:15:09,840 Speaker 1: very well. The Extra Dark Tour is epic and the 284 00:15:09,920 --> 00:15:11,600 Speaker 1: story well, they never turned on the lights and so 285 00:15:11,640 --> 00:15:15,760 Speaker 1: nobody could tell if they were there. Yeah, they all right, 286 00:15:15,840 --> 00:15:17,920 Speaker 1: And then someone at the end said that maybe it's 287 00:15:17,920 --> 00:15:20,160 Speaker 1: a black hole. So they were sort of close to 288 00:15:20,320 --> 00:15:23,720 Speaker 1: the truth here, maybe yeah, yeah, maybe there are masquerining 289 00:15:23,760 --> 00:15:26,560 Speaker 1: as black holes. All right, let's jump into this subject 290 00:15:26,600 --> 00:15:28,720 Speaker 1: of whether or not a black hole is actually a 291 00:15:28,720 --> 00:15:32,080 Speaker 1: black hole and what else it could be. So let's 292 00:15:32,120 --> 00:15:35,360 Speaker 1: start from the basics. Daniel, why do we think we've 293 00:15:35,400 --> 00:15:38,760 Speaker 1: seen black holes? It's a really fun story. Actually, we 294 00:15:38,840 --> 00:15:41,560 Speaker 1: did a podcast episode about the discovery of black holes, 295 00:15:41,640 --> 00:15:44,000 Speaker 1: and it's really cool to trace the history of the 296 00:15:44,080 --> 00:15:48,360 Speaker 1: idea and then the history of the observation, like, this 297 00:15:48,400 --> 00:15:50,880 Speaker 1: is not something I think we could have ever discovered 298 00:15:51,120 --> 00:15:53,480 Speaker 1: if we didn't know to look for it, because in 299 00:15:53,520 --> 00:15:56,000 Speaker 1: the end, the evidence is not a smoking gun. It's 300 00:15:56,000 --> 00:15:58,160 Speaker 1: like the kind of thing you can hunt for subtle 301 00:15:58,200 --> 00:16:01,080 Speaker 1: signals of if you know to see it. So it's 302 00:16:01,120 --> 00:16:03,200 Speaker 1: sort of like, you know, a story. The moral of 303 00:16:03,200 --> 00:16:06,120 Speaker 1: the story is you should really think carefully about what's 304 00:16:06,120 --> 00:16:07,800 Speaker 1: out there in the universe, because it might give you 305 00:16:07,840 --> 00:16:10,920 Speaker 1: crazy ideas for what to look for. And this crazy 306 00:16:10,960 --> 00:16:14,800 Speaker 1: idea came from Albert Einstein himself in nineteen fifteen when 307 00:16:14,840 --> 00:16:16,960 Speaker 1: he came up with general relativity, which is the way 308 00:16:17,000 --> 00:16:20,760 Speaker 1: to describe how space bends in response to mass, and 309 00:16:20,800 --> 00:16:23,360 Speaker 1: then how mass moves through that bend space. So that's 310 00:16:23,400 --> 00:16:25,960 Speaker 1: the theory of general relativity, and just a year later 311 00:16:26,000 --> 00:16:29,160 Speaker 1: somebody solved his equations and discovered they predicted something really, 312 00:16:29,200 --> 00:16:31,640 Speaker 1: really weird. And that's when the idea of a black 313 00:16:31,680 --> 00:16:34,840 Speaker 1: hole was born. Now more than a hundred years ago, right, 314 00:16:34,920 --> 00:16:36,720 Speaker 1: maybe you can step us through this a little bit. 315 00:16:36,760 --> 00:16:39,160 Speaker 1: So what was Einstein looking at? Like, he was looking 316 00:16:39,200 --> 00:16:42,000 Speaker 1: at the equations of gravity, and like, what happens if 317 00:16:42,040 --> 00:16:44,680 Speaker 1: you get enough gravity into into or mass into one 318 00:16:44,880 --> 00:16:47,480 Speaker 1: tiny spot? How does that affect the equations that he 319 00:16:47,520 --> 00:16:49,640 Speaker 1: was coming up with? What exactly was he looking at? 320 00:16:49,800 --> 00:16:52,880 Speaker 1: He was looking for a general equation, one that described, 321 00:16:53,120 --> 00:16:55,760 Speaker 1: you know how space bends when you have mass in it. 322 00:16:55,840 --> 00:16:57,760 Speaker 1: So if you put a son here and you put 323 00:16:57,760 --> 00:17:00,760 Speaker 1: a planet there, then how does space curve? And then 324 00:17:00,920 --> 00:17:03,600 Speaker 1: how do things move through that curved space? But his 325 00:17:03,680 --> 00:17:06,639 Speaker 1: equations are famously hard to solve, Like, we can't solve 326 00:17:06,680 --> 00:17:09,720 Speaker 1: them for even very basic simple scenarios like a son 327 00:17:09,880 --> 00:17:11,879 Speaker 1: and a planet. We've only been able to solve them 328 00:17:11,920 --> 00:17:15,480 Speaker 1: for very simple situations like an empty universe with nothing 329 00:17:15,480 --> 00:17:19,800 Speaker 1: in it, or a universe like filled smoothly with matter 330 00:17:19,880 --> 00:17:22,560 Speaker 1: with no lumps or bumps at all. These kinds of 331 00:17:22,640 --> 00:17:25,359 Speaker 1: very simple situations lead to solutions where we say, if 332 00:17:25,400 --> 00:17:27,840 Speaker 1: you have a certain mass distribution, then I can tell 333 00:17:27,880 --> 00:17:31,119 Speaker 1: you how space bends. It's not easy for a given 334 00:17:31,200 --> 00:17:34,760 Speaker 1: arbitrary mass distribution to solve Einstein's equations and know how 335 00:17:34,840 --> 00:17:37,960 Speaker 1: space bends. It's like, it's very difficult. Einstein's equations just 336 00:17:38,000 --> 00:17:40,159 Speaker 1: tell you, like the rules that it has to follow. 337 00:17:40,200 --> 00:17:42,399 Speaker 1: But as we talked about once in the podcast, knowing 338 00:17:42,400 --> 00:17:45,000 Speaker 1: the equations doesn't necessarily mean you know how to find 339 00:17:45,080 --> 00:17:47,640 Speaker 1: a solution. And so even though we had these equations, 340 00:17:47,760 --> 00:17:50,919 Speaker 1: nobody had ever solved his equations, including Einstein. When he 341 00:17:50,960 --> 00:17:53,320 Speaker 1: put them out there, he was like, here are the equations. 342 00:17:53,320 --> 00:17:55,880 Speaker 1: But just a year later, a soldier on the front 343 00:17:55,920 --> 00:17:59,360 Speaker 1: lines of World War one, kurse short child, solve them 344 00:17:59,359 --> 00:18:02,440 Speaker 1: for this easy scenario where you have a really immense 345 00:18:02,480 --> 00:18:04,679 Speaker 1: amount of mass all in one place. And so that 346 00:18:04,760 --> 00:18:07,520 Speaker 1: was the first ever solution to the Einstein equations. This 347 00:18:07,680 --> 00:18:11,040 Speaker 1: one really weird, extreme scenario. And sometimes in math, like 348 00:18:11,119 --> 00:18:14,440 Speaker 1: the really extreme weird scenarios are easier to solve than 349 00:18:14,480 --> 00:18:18,600 Speaker 1: the more complicated general ones. I see. So Einstein didn't 350 00:18:18,640 --> 00:18:21,399 Speaker 1: even think about black holes. He just put out, you know, 351 00:18:21,520 --> 00:18:24,600 Speaker 1: general equations for like everyday life and somebody looked at 352 00:18:24,600 --> 00:18:26,280 Speaker 1: that and say, well, what if I crank up the 353 00:18:26,359 --> 00:18:29,280 Speaker 1: mass and put it onto one spot that leads to 354 00:18:29,320 --> 00:18:32,840 Speaker 1: like a special solution, which is a black hole. Precisely 355 00:18:32,880 --> 00:18:35,160 Speaker 1: in Einstein was like, wow, nice work and never thought 356 00:18:35,160 --> 00:18:37,920 Speaker 1: of that. That's very cool. He was like man penning 357 00:18:37,960 --> 00:18:40,280 Speaker 1: himself on the back, kind of like, wow, that's a 358 00:18:40,359 --> 00:18:43,000 Speaker 1: pretty awesome thing that came from something I did. Yeah, 359 00:18:43,040 --> 00:18:45,240 Speaker 1: I think it's always cool in science to see somebody 360 00:18:45,280 --> 00:18:46,920 Speaker 1: follow up on your work. You know, you don't want 361 00:18:46,920 --> 00:18:48,520 Speaker 1: to write a paper and then have nobody read it 362 00:18:48,560 --> 00:18:50,600 Speaker 1: and nobody respond to it. You want people to read 363 00:18:50,600 --> 00:18:52,720 Speaker 1: it and build on it. And of course lots of 364 00:18:52,720 --> 00:18:54,359 Speaker 1: people have done that for now, but this was like 365 00:18:54,400 --> 00:18:56,160 Speaker 1: the first step. This is the first time somebody took 366 00:18:56,160 --> 00:18:59,160 Speaker 1: his equations and said, all right, you know what kind 367 00:18:59,200 --> 00:19:02,520 Speaker 1: of universe is him this describe So Einstein hadn't really 368 00:19:02,560 --> 00:19:04,959 Speaker 1: thought about this idea of like a volume in space 369 00:19:05,080 --> 00:19:07,280 Speaker 1: that if you go into it you can never escape. No, 370 00:19:07,400 --> 00:19:09,600 Speaker 1: he had not thought about that at all. And in fact, 371 00:19:09,640 --> 00:19:13,959 Speaker 1: even though this solution existed in general relativity since the 372 00:19:14,040 --> 00:19:18,320 Speaker 1: nineteen sixteen, people didn't really understand the impact of the concept. 373 00:19:18,359 --> 00:19:20,520 Speaker 1: What it meant, you know, what it would actually look 374 00:19:20,560 --> 00:19:23,399 Speaker 1: like in space until decades later. It was like in 375 00:19:23,400 --> 00:19:27,159 Speaker 1: the fifties that this concept of an event horizon was 376 00:19:27,240 --> 00:19:29,360 Speaker 1: even invented. You know, before that people were like, well, 377 00:19:29,400 --> 00:19:31,360 Speaker 1: what would that mean? Would it just looks like sort 378 00:19:31,359 --> 00:19:34,200 Speaker 1: of a frozen star because there's so much gravity to 379 00:19:34,359 --> 00:19:37,080 Speaker 1: be crazy time dilation. So it wasn't until the fifties 380 00:19:37,080 --> 00:19:39,840 Speaker 1: of people realized that no information could leak out of this, 381 00:19:39,880 --> 00:19:42,680 Speaker 1: that there was like a barrier beyond which all information 382 00:19:42,800 --> 00:19:45,760 Speaker 1: was hidden. So it takes decades sometimes to understand the 383 00:19:45,800 --> 00:19:49,560 Speaker 1: consequences even of theoretical ideas interesting. So I guess the 384 00:19:49,640 --> 00:19:52,480 Speaker 1: black hole wasn't really a black hole for for forty 385 00:19:52,560 --> 00:19:55,200 Speaker 1: years until somebody figured out that, you know, if you 386 00:19:55,240 --> 00:19:57,320 Speaker 1: actually were in the presence of one, it would look 387 00:19:57,320 --> 00:20:00,159 Speaker 1: like a giant black ball. Yeah, but even then it 388 00:20:00,240 --> 00:20:02,480 Speaker 1: was like a crazy idea. And you have to understand, 389 00:20:02,680 --> 00:20:06,640 Speaker 1: physics is filled with crazy hypothetical ideas that nobody believes 390 00:20:06,680 --> 00:20:09,760 Speaker 1: are real, that nobody thinks actually exist in our universe. 391 00:20:09,800 --> 00:20:12,240 Speaker 1: Like if you read papers, there are papers describing all 392 00:20:12,280 --> 00:20:15,560 Speaker 1: sorts of crazy, bonkers things, and these are just theorists exploring, 393 00:20:15,600 --> 00:20:18,160 Speaker 1: like what could happen. What about this, could this work? 394 00:20:18,359 --> 00:20:20,920 Speaker 1: What would it mean? And this was in that category 395 00:20:20,960 --> 00:20:23,640 Speaker 1: for a long long time, not something anybody ever expected 396 00:20:23,680 --> 00:20:26,640 Speaker 1: to see in the universe or actually observe. And that 397 00:20:26,720 --> 00:20:29,760 Speaker 1: changed in the sixties when there was the discovery of 398 00:20:29,840 --> 00:20:32,600 Speaker 1: neutron stars. I made a podcast recently about the discovery 399 00:20:32,600 --> 00:20:35,720 Speaker 1: of pulsars, which was very cool. That shocked people because 400 00:20:35,760 --> 00:20:38,560 Speaker 1: these are closely related to black holes. They're very dense, 401 00:20:38,680 --> 00:20:41,840 Speaker 1: very compact objects with incredible gravity. So people start to think, 402 00:20:41,840 --> 00:20:44,359 Speaker 1: hold on a second, if neutron stars are real, could 403 00:20:44,400 --> 00:20:47,800 Speaker 1: black holes be real? Also, so neutron stars are totally 404 00:20:47,840 --> 00:20:50,560 Speaker 1: different because you can still escape a neutron star, right, Yeah, 405 00:20:50,600 --> 00:20:53,159 Speaker 1: they don't have an event horizon, but they are crazy 406 00:20:53,320 --> 00:20:56,359 Speaker 1: dense gravitational objects. Okay, so we found it, and that 407 00:20:56,720 --> 00:20:59,640 Speaker 1: made people think, Hey, maybe this other crazy idea called 408 00:20:59,640 --> 00:21:02,200 Speaker 1: the black all exists out there. Let's go look for it. Yeah. 409 00:21:02,240 --> 00:21:05,520 Speaker 1: And then around the same time, we started seeing unexplained 410 00:21:05,600 --> 00:21:09,120 Speaker 1: radiation from the sky, like people were sending rockets up 411 00:21:09,280 --> 00:21:12,320 Speaker 1: into the upper atmosphere to measure the radiation from space, 412 00:21:12,640 --> 00:21:15,600 Speaker 1: and they found an incredibly bright X ray source that 413 00:21:15,640 --> 00:21:19,120 Speaker 1: nobody could explain, like something out there was generating very 414 00:21:19,240 --> 00:21:22,800 Speaker 1: very high energy photons. To have high energy photons, you 415 00:21:22,840 --> 00:21:25,840 Speaker 1: need like really really hot gas, and you know, you 416 00:21:25,880 --> 00:21:27,960 Speaker 1: look in the sky and you don't see anything there, 417 00:21:28,000 --> 00:21:30,280 Speaker 1: so you're like, what's out there? It's dark and it's 418 00:21:30,320 --> 00:21:33,600 Speaker 1: generating this crazy X ray source. So that was weird 419 00:21:33,680 --> 00:21:35,960 Speaker 1: and interesting. Well, I mean it's dark and like the 420 00:21:36,080 --> 00:21:38,840 Speaker 1: visible light spectrum, is that what you mean? Right, Like 421 00:21:39,000 --> 00:21:40,480 Speaker 1: you can't see with the naked eye, but if you 422 00:21:40,520 --> 00:21:42,440 Speaker 1: have an X ray telescope you can see the light 423 00:21:42,560 --> 00:21:44,480 Speaker 1: in that frequency. Yeah, And so that tells you there's 424 00:21:44,560 --> 00:21:47,280 Speaker 1: something out there which is glowing only in this very 425 00:21:47,400 --> 00:21:51,000 Speaker 1: very high energy photons. That's weird, you know, And so 426 00:21:51,080 --> 00:21:52,879 Speaker 1: we knew it was something and it had to be 427 00:21:52,920 --> 00:21:54,840 Speaker 1: kind of small because it was like not a whole 428 00:21:54,840 --> 00:21:57,120 Speaker 1: lot of room around there. You could like pinpoint where 429 00:21:57,160 --> 00:22:00,000 Speaker 1: this was coming from, and it couldn't be some like huge, 430 00:22:00,200 --> 00:22:03,280 Speaker 1: massive extended object because there was like other stuff nearby. 431 00:22:03,560 --> 00:22:05,240 Speaker 1: And that was the sort of the second clue, like 432 00:22:05,320 --> 00:22:06,800 Speaker 1: we saw that there was something out there that was 433 00:22:06,960 --> 00:22:09,160 Speaker 1: dark because we couldn't see it in a visible light, 434 00:22:09,280 --> 00:22:11,720 Speaker 1: but it was generating these X rays and it was 435 00:22:11,800 --> 00:22:15,159 Speaker 1: pretty small. We found another example of one that was 436 00:22:15,320 --> 00:22:19,240 Speaker 1: orbiting a super giant blue star and it was emitting 437 00:22:19,280 --> 00:22:22,639 Speaker 1: this crazy radiation, but there was nothing visible there and 438 00:22:22,640 --> 00:22:25,199 Speaker 1: there wasn't a lot of room for anything, So that 439 00:22:25,280 --> 00:22:27,760 Speaker 1: suggested it had to be something which was like very 440 00:22:27,760 --> 00:22:30,720 Speaker 1: small but very high energy. Did you call them like 441 00:22:30,920 --> 00:22:35,520 Speaker 1: X stars or x essence? There were so small, extra small, 442 00:22:36,200 --> 00:22:37,919 Speaker 1: all right, So then people went out to look for 443 00:22:38,000 --> 00:22:40,920 Speaker 1: black holes. But I guess the question is was what 444 00:22:40,960 --> 00:22:44,720 Speaker 1: they found actually black holes? So let's get into that 445 00:22:44,800 --> 00:22:48,439 Speaker 1: question and what this dark star is and what it means. 446 00:22:48,440 --> 00:23:03,280 Speaker 1: But first let's take a quick break, all right. I 447 00:23:03,320 --> 00:23:07,200 Speaker 1: know we are questioning black holes. Are black holes actually 448 00:23:07,240 --> 00:23:10,600 Speaker 1: black holes, like in the sense of the concept of 449 00:23:10,600 --> 00:23:13,560 Speaker 1: a black hole that Einstein helped figure out, or maybe 450 00:23:13,640 --> 00:23:15,639 Speaker 1: there could be something else that acts like something that 451 00:23:15,680 --> 00:23:17,640 Speaker 1: could be a black hole. Yeah. I feel like we're 452 00:23:17,680 --> 00:23:20,760 Speaker 1: in you know, act two of some murder mystery where 453 00:23:20,760 --> 00:23:22,680 Speaker 1: we have a bunch of clues and we have a suspect, 454 00:23:22,760 --> 00:23:25,399 Speaker 1: and we're like, all these clues pointed that suspect, and 455 00:23:25,400 --> 00:23:28,200 Speaker 1: then we're wondering, hole on a second, is it possible 456 00:23:28,560 --> 00:23:31,720 Speaker 1: that it was actually the ex husband or the sun 457 00:23:31,880 --> 00:23:33,760 Speaker 1: or whatever, were that one character that you didn't pay 458 00:23:33,760 --> 00:23:36,320 Speaker 1: attention to, and you have to reassess your evidence. You're like, 459 00:23:36,359 --> 00:23:39,439 Speaker 1: what do we actually know about who killed this person? 460 00:23:39,560 --> 00:23:41,560 Speaker 1: So this is the part where you like twiddle your 461 00:23:42,000 --> 00:23:46,560 Speaker 1: mustache and like what if, Yeah, you know, maybe that 462 00:23:46,680 --> 00:23:49,160 Speaker 1: was just a paste on mustache or maybe there's shaved 463 00:23:49,200 --> 00:23:51,560 Speaker 1: their mustache off or something. You know, the whole thing 464 00:23:51,640 --> 00:23:53,680 Speaker 1: was just a deep fick. And so I think it's 465 00:23:53,760 --> 00:23:56,760 Speaker 1: useful to like catalog exactly what we do know about 466 00:23:56,760 --> 00:23:59,520 Speaker 1: these objects that we've been calling black holes. But maybe 467 00:23:59,560 --> 00:24:02,440 Speaker 1: it's really just the ex husband or an ex black 468 00:24:02,440 --> 00:24:06,280 Speaker 1: hole husband. Anyways, So you're telling me that we sort 469 00:24:06,320 --> 00:24:09,520 Speaker 1: of figured out theoretically that there could be black holes 470 00:24:09,560 --> 00:24:12,160 Speaker 1: out there, and then we saw some clues and then 471 00:24:12,200 --> 00:24:15,160 Speaker 1: we actually went and found what we think are black holes. Yeah, 472 00:24:15,160 --> 00:24:18,800 Speaker 1: we have identified these objects out there in space, and 473 00:24:18,920 --> 00:24:22,240 Speaker 1: essentially we know that they are small, that they are dark, 474 00:24:22,600 --> 00:24:25,040 Speaker 1: and that they are heavy. Right. We know they're small 475 00:24:25,080 --> 00:24:28,080 Speaker 1: because sometimes we see other stars orbiting nearby them and 476 00:24:28,119 --> 00:24:30,480 Speaker 1: coming very very close, so they can't be that big. 477 00:24:30,600 --> 00:24:32,240 Speaker 1: We know that they are dark because they don't give 478 00:24:32,240 --> 00:24:34,760 Speaker 1: off a lot of visible radiation or almost none or 479 00:24:34,840 --> 00:24:37,320 Speaker 1: exactly none, and We know that they are heavy because 480 00:24:37,359 --> 00:24:41,280 Speaker 1: we can measure their gravitational impact on other stars nearby. 481 00:24:41,359 --> 00:24:44,920 Speaker 1: We see stars like whizzing around them really fast, which 482 00:24:44,960 --> 00:24:47,720 Speaker 1: only happens you have like a lot of gravity. So 483 00:24:47,960 --> 00:24:50,880 Speaker 1: we have something that's small and dark and heavy. And 484 00:24:51,080 --> 00:24:53,440 Speaker 1: for a long time we had, you know, only one 485 00:24:53,680 --> 00:24:56,480 Speaker 1: candidate that could fit the bill, one candidate that could 486 00:24:56,480 --> 00:24:59,480 Speaker 1: satisfy all of those requirements, and that was black holes. 487 00:25:00,359 --> 00:25:02,880 Speaker 1: So I guess, yeah, I guess from a far enough distance, 488 00:25:02,960 --> 00:25:04,760 Speaker 1: that's how you would define it, right, if you're far 489 00:25:04,800 --> 00:25:08,960 Speaker 1: away enough, it's just something that is not visible in 490 00:25:09,000 --> 00:25:12,359 Speaker 1: the in the light invisible light spectrum. But it's also 491 00:25:12,440 --> 00:25:15,720 Speaker 1: very heavy, yeah, because we've never like actually seen an 492 00:25:15,720 --> 00:25:18,520 Speaker 1: event horizon in the sense that we haven't like dropped 493 00:25:18,560 --> 00:25:21,440 Speaker 1: something in it and see it disappear, you know, or 494 00:25:21,520 --> 00:25:24,840 Speaker 1: measure the gravitational impact on it. Even the direct photograph 495 00:25:24,960 --> 00:25:27,240 Speaker 1: we have of a black hole, right, the one that 496 00:25:27,400 --> 00:25:29,919 Speaker 1: was a big hullabaloo in the news and etcetera, Like, 497 00:25:29,960 --> 00:25:31,679 Speaker 1: what is it? Really what you're looking at is an 498 00:25:31,640 --> 00:25:34,720 Speaker 1: accretion disc is the gas around the black hole, and 499 00:25:34,800 --> 00:25:37,520 Speaker 1: in the center you see something black. So again you 500 00:25:37,560 --> 00:25:39,920 Speaker 1: know that it's small, that it's dark and it's heavy, 501 00:25:40,000 --> 00:25:44,119 Speaker 1: you don't actually know it's nature. And the argument that 502 00:25:44,160 --> 00:25:46,600 Speaker 1: it's a black hole is basically like nothing else can 503 00:25:46,640 --> 00:25:49,200 Speaker 1: do that. So if you can think of something else 504 00:25:49,320 --> 00:25:51,679 Speaker 1: that can do that, then you know, maybe it's that 505 00:25:51,760 --> 00:25:55,440 Speaker 1: other thing instead. But we've also seen gravitational waves right 506 00:25:55,480 --> 00:25:57,639 Speaker 1: from black holes or what we think are black holes 507 00:25:57,840 --> 00:26:00,919 Speaker 1: crashing into each other. We have exactly we've seen gravitational 508 00:26:00,960 --> 00:26:04,360 Speaker 1: waves from black holes merging from neutron stars merging from 509 00:26:04,359 --> 00:26:07,439 Speaker 1: neutron stars, and black holes merging. What does that tell us? 510 00:26:07,480 --> 00:26:10,320 Speaker 1: It tells us again that there's something very massive with 511 00:26:10,359 --> 00:26:13,959 Speaker 1: a lot of gravity and that general relativity mostly works, 512 00:26:14,320 --> 00:26:17,280 Speaker 1: So that could be explained by something else, you know, 513 00:26:17,440 --> 00:26:20,920 Speaker 1: just as massive and small and dark in that same 514 00:26:20,960 --> 00:26:25,600 Speaker 1: location that would also emit gravitational waves, like anything that 515 00:26:25,680 --> 00:26:29,040 Speaker 1: dense and small would emit gravitational waves also, So that's 516 00:26:29,080 --> 00:26:32,320 Speaker 1: also not a unique signature of black holes. Like let's 517 00:26:32,359 --> 00:26:35,440 Speaker 1: not jump to conclusions. And so maybe a possible thing 518 00:26:35,520 --> 00:26:38,080 Speaker 1: this could be instead of a black hole is something 519 00:26:38,119 --> 00:26:41,440 Speaker 1: called a dark star, So like what is the dark star? Then? Yeah, 520 00:26:41,480 --> 00:26:44,440 Speaker 1: So the idea is, you know, exercise your brain, think 521 00:26:44,440 --> 00:26:47,400 Speaker 1: about other ways to arrange matter that gives the same 522 00:26:47,440 --> 00:26:50,600 Speaker 1: sort of outwards appearance but looks different fundamentally. And so 523 00:26:50,640 --> 00:26:54,200 Speaker 1: a dark star is like again very very dense matter. 524 00:26:54,560 --> 00:26:57,800 Speaker 1: You know, you take star and it's done burning, and 525 00:26:57,840 --> 00:27:00,679 Speaker 1: so it no longer can provide like ready Asian pressure 526 00:27:00,760 --> 00:27:04,439 Speaker 1: to push outwards, and gravity takes over and it pulls 527 00:27:04,480 --> 00:27:07,359 Speaker 1: the star in and it collapses into something very very dense. 528 00:27:07,440 --> 00:27:10,080 Speaker 1: And there's lots of different scenarios. One scenarios it becomes 529 00:27:10,080 --> 00:27:12,480 Speaker 1: a neutron star, right, and that's a scenario where to 530 00:27:12,520 --> 00:27:16,600 Speaker 1: avoids total gravitational collapse because of the neutrons putting pressure 531 00:27:16,640 --> 00:27:19,040 Speaker 1: on each other. But there's this other idea that it 532 00:27:19,080 --> 00:27:22,480 Speaker 1: could collapse to something even more dense than a neutron star, 533 00:27:22,680 --> 00:27:24,720 Speaker 1: but not a black hole. And so that's what a 534 00:27:24,800 --> 00:27:28,159 Speaker 1: dark star is. It's got something called a plank core 535 00:27:28,359 --> 00:27:30,919 Speaker 1: where the core is collapsed and gravitationally, but it doesn't 536 00:27:30,920 --> 00:27:32,840 Speaker 1: go all the way to a black hole because something 537 00:27:32,880 --> 00:27:36,119 Speaker 1: prevents that, something does actually push back. Interesting, Yeah, I 538 00:27:36,119 --> 00:27:38,960 Speaker 1: remember a neutron star. It's like the stuff is squeezed 539 00:27:39,000 --> 00:27:43,360 Speaker 1: together so much that it like dissolves into almost pure corks. Right, 540 00:27:43,560 --> 00:27:45,960 Speaker 1: And so you have this giant wall of corks kind 541 00:27:46,000 --> 00:27:49,560 Speaker 1: of holding together because there's enough energy there to pushing 542 00:27:50,080 --> 00:27:53,159 Speaker 1: the quarts pushing each other away, but it's still super 543 00:27:53,200 --> 00:27:55,760 Speaker 1: super dense. Yeah, and we do not understand the internal 544 00:27:55,840 --> 00:27:58,040 Speaker 1: physics of the neutron star very well at all. It's 545 00:27:58,080 --> 00:28:01,000 Speaker 1: like a really active area of research, and it's really 546 00:28:01,000 --> 00:28:04,119 Speaker 1: difficult to study because corks are complicated. You know, they 547 00:28:04,200 --> 00:28:06,119 Speaker 1: used the strong force, which is a big mess to 548 00:28:06,119 --> 00:28:08,840 Speaker 1: do calculations in. Every time you emit a gluon, it 549 00:28:08,840 --> 00:28:11,400 Speaker 1: emits more gluons. You have infinite numbers of gluons every 550 00:28:11,400 --> 00:28:13,160 Speaker 1: time you want to do a calculation. So we don't 551 00:28:13,200 --> 00:28:16,560 Speaker 1: really understand what's going on inside a neutron star. But roughly, yes, 552 00:28:16,840 --> 00:28:19,680 Speaker 1: it's like a huge particle because all the corks are 553 00:28:19,680 --> 00:28:23,080 Speaker 1: bound together into this incredible you know, like ten fifteen 554 00:28:23,160 --> 00:28:26,040 Speaker 1: kilometer objects that's the mass of the Sun. So you're 555 00:28:26,080 --> 00:28:28,840 Speaker 1: saying that there's another step that you can take between 556 00:28:28,880 --> 00:28:31,760 Speaker 1: that and a black hole, which is maybe a dark star. 557 00:28:32,320 --> 00:28:35,119 Speaker 1: And so what's happening, Like are the corks somehow running 558 00:28:35,160 --> 00:28:37,720 Speaker 1: out of juice and so they squeeze in a little further, 559 00:28:38,000 --> 00:28:40,479 Speaker 1: Like what's going on? How would this dark star come 560 00:28:40,560 --> 00:28:42,800 Speaker 1: to be yes. So the reason neutron star is stable 561 00:28:42,960 --> 00:28:45,160 Speaker 1: is because the corks are pushing back against each other. 562 00:28:45,520 --> 00:28:49,360 Speaker 1: And so to go deeper and darker and go beyond 563 00:28:49,360 --> 00:28:51,800 Speaker 1: a neutron star, you need more gravity. So if you 564 00:28:51,880 --> 00:28:54,360 Speaker 1: have more mass than a neutron star can be, like 565 00:28:54,600 --> 00:28:57,240 Speaker 1: neutron stars can be at most, you know, mass, maybe 566 00:28:57,320 --> 00:28:59,440 Speaker 1: twice the mass of the Sun or so, we're not 567 00:28:59,520 --> 00:29:02,080 Speaker 1: exactly sure. If you have more mass than that, then 568 00:29:02,200 --> 00:29:05,200 Speaker 1: you can have enough gravity to overcome whether corks are 569 00:29:05,240 --> 00:29:07,680 Speaker 1: doing to resist the collapse, just the same way like 570 00:29:07,720 --> 00:29:11,280 Speaker 1: our son currently is resisting gravitational collapse. It's doing so 571 00:29:11,360 --> 00:29:14,640 Speaker 1: by burning and his fusion and photons pushing out. The 572 00:29:14,680 --> 00:29:17,400 Speaker 1: neutron stars pushing out because of the cork forces. If 573 00:29:17,440 --> 00:29:19,320 Speaker 1: you have more gravity, you can overcome that, and then 574 00:29:19,360 --> 00:29:22,360 Speaker 1: you can go deeper. And there's another layer. People think 575 00:29:22,440 --> 00:29:25,200 Speaker 1: this is all hypothetical. People think that there's another layer 576 00:29:25,320 --> 00:29:28,520 Speaker 1: where quantum mechanics itself prevents you from getting to a 577 00:29:28,520 --> 00:29:31,800 Speaker 1: black hole. So the particles get so close that the 578 00:29:31,880 --> 00:29:36,440 Speaker 1: quantum mechanics uncertainty principle prevents you from collapsing even further. Interesting, 579 00:29:36,520 --> 00:29:39,160 Speaker 1: so I would have like a neutron star super dance, 580 00:29:39,280 --> 00:29:42,640 Speaker 1: and I add more neutrons to it, more mass to it, 581 00:29:43,400 --> 00:29:47,280 Speaker 1: and before it actually collapses into a black hole, maybe 582 00:29:47,360 --> 00:29:52,120 Speaker 1: there's something about quantum mechanics that keeps it not collapsing, 583 00:29:52,240 --> 00:29:55,480 Speaker 1: because quantum mechanics doesn't like having particles localized in a 584 00:29:55,560 --> 00:29:59,160 Speaker 1: very specific region. Right, The whole idea of a singularity 585 00:29:59,240 --> 00:30:02,400 Speaker 1: inside a black whole huge amount of mass and basically 586 00:30:02,520 --> 00:30:05,560 Speaker 1: zero volume, is nonsensical when it comes to quantum mechanics. 587 00:30:05,640 --> 00:30:08,560 Speaker 1: Quantum mechanics says, if that happens, then the uncertainty and 588 00:30:08,600 --> 00:30:11,320 Speaker 1: the momentum of all those particles would basically be infinite, 589 00:30:11,360 --> 00:30:13,480 Speaker 1: so they would basically have infinite energy, and then they 590 00:30:13,480 --> 00:30:16,280 Speaker 1: would escape. The whole thing of a singularity doesn't make 591 00:30:16,320 --> 00:30:18,840 Speaker 1: sense from the point of view of quantum mechanics. So 592 00:30:18,880 --> 00:30:21,640 Speaker 1: the idea is maybe quantum mechanics prevents you from getting there, 593 00:30:21,920 --> 00:30:25,280 Speaker 1: that as the particles are collapsing, that the uncertainty principle 594 00:30:25,360 --> 00:30:28,080 Speaker 1: prevents them from getting so close as to actually form 595 00:30:28,160 --> 00:30:30,640 Speaker 1: a singularity. I guess the key thing here is that 596 00:30:30,680 --> 00:30:33,880 Speaker 1: it's small, it's dark, it's super dense, but it's not 597 00:30:33,960 --> 00:30:37,240 Speaker 1: technically a black hole because it doesn't get dense enough 598 00:30:37,400 --> 00:30:40,600 Speaker 1: to form an event horizon, which is like the actual 599 00:30:40,720 --> 00:30:43,160 Speaker 1: like point where nothing can escape. Yeah, this dark star 600 00:30:43,160 --> 00:30:45,720 Speaker 1: would not have an event horizon exactly. And also it 601 00:30:45,720 --> 00:30:48,080 Speaker 1: wouldn't have a singularity at its core. You know, the 602 00:30:48,360 --> 00:30:51,600 Speaker 1: really defining characteristics of a black hole are the singularity 603 00:30:51,640 --> 00:30:54,280 Speaker 1: at its core and the event horizon. And so this 604 00:30:54,320 --> 00:30:56,959 Speaker 1: would be a very very dense object, even denser than 605 00:30:57,000 --> 00:31:00,560 Speaker 1: neutron stars, but not actually a black hole, and quantum 606 00:31:00,560 --> 00:31:03,440 Speaker 1: mechanics would be preventing that. And something else that's super 607 00:31:03,440 --> 00:31:06,520 Speaker 1: fascinating about these objects is that they're not stable like 608 00:31:06,520 --> 00:31:08,920 Speaker 1: a neutron star is stable. It's a balance between these 609 00:31:08,920 --> 00:31:12,560 Speaker 1: two foss squeezing down gravity and pushing out because of 610 00:31:12,600 --> 00:31:17,120 Speaker 1: the corks, this plank core is not actually stable. People 611 00:31:17,120 --> 00:31:19,880 Speaker 1: think that quantum mechanics is more like a rubber sheet, 612 00:31:20,160 --> 00:31:22,440 Speaker 1: you know that You're like it collapses and then it 613 00:31:22,480 --> 00:31:25,600 Speaker 1: bounces back, so it provides like a maximum density or 614 00:31:25,600 --> 00:31:27,800 Speaker 1: like a minimum size to this object, and then it 615 00:31:27,840 --> 00:31:30,880 Speaker 1: pushes back and then the star expands again. But wouldn't 616 00:31:30,880 --> 00:31:34,040 Speaker 1: that be evidence or an argument against these dark stars, 617 00:31:34,080 --> 00:31:36,240 Speaker 1: Like if they don't last very long, why do we 618 00:31:36,280 --> 00:31:38,560 Speaker 1: think they could exist, right, Well, they might not last 619 00:31:38,600 --> 00:31:41,760 Speaker 1: that long in their own time, right, but the gravity 620 00:31:41,840 --> 00:31:44,800 Speaker 1: is really really intense and so time is slowed down. 621 00:31:45,080 --> 00:31:47,600 Speaker 1: So what these dark stars might be is like this 622 00:31:47,640 --> 00:31:50,920 Speaker 1: object that's collapsing, that's going to bounce back from this 623 00:31:50,960 --> 00:31:53,360 Speaker 1: plank core. But from our point of view, it might 624 00:31:53,400 --> 00:31:56,560 Speaker 1: take billions or trillions of years for that bounds to 625 00:31:56,600 --> 00:32:00,400 Speaker 1: happen because it's super slowed down by the gravity aational 626 00:32:00,440 --> 00:32:03,200 Speaker 1: time dilation. So it looks stable to us on our 627 00:32:03,240 --> 00:32:05,320 Speaker 1: time scale, but you know, if you're inside of it, 628 00:32:05,400 --> 00:32:07,440 Speaker 1: the whole thing would be over in a blip. It's 629 00:32:07,440 --> 00:32:10,400 Speaker 1: like a loophole. Like it's unstable and it won't last 630 00:32:10,400 --> 00:32:12,520 Speaker 1: for long. But it depends on what you mean by long, 631 00:32:12,640 --> 00:32:14,240 Speaker 1: all right, So so from our point of view it 632 00:32:14,280 --> 00:32:17,000 Speaker 1: would look like a stable thing, but it's actually not. Yeah, 633 00:32:17,000 --> 00:32:19,920 Speaker 1: and it doesn't have an event horizon, and so unlike 634 00:32:19,920 --> 00:32:23,320 Speaker 1: a black hole, it could actually emit information. It could 635 00:32:23,360 --> 00:32:26,280 Speaker 1: like actually leak photons. But I guess why is it 636 00:32:26,360 --> 00:32:28,800 Speaker 1: dark and why is it emitting X rays but not 637 00:32:28,960 --> 00:32:31,240 Speaker 1: visible light? Yeah? Great question, right, Because we have to 638 00:32:31,280 --> 00:32:33,840 Speaker 1: match all the observations for these things to explain what 639 00:32:33,880 --> 00:32:36,480 Speaker 1: we see. They have to actually predict what we see. 640 00:32:36,560 --> 00:32:39,480 Speaker 1: So how could these things be dark? Again, it's gravity 641 00:32:39,560 --> 00:32:42,840 Speaker 1: and the relativistic effects. If these things really do have 642 00:32:42,920 --> 00:32:45,680 Speaker 1: this much gravity, because they're very, very dense objects, so 643 00:32:45,760 --> 00:32:48,360 Speaker 1: much so that they have this crazy time dilation. They 644 00:32:48,360 --> 00:32:51,000 Speaker 1: have another effect on things, which is that they read shift. 645 00:32:51,120 --> 00:32:54,240 Speaker 1: So they might be emitting photons, but those photons would 646 00:32:54,240 --> 00:32:57,320 Speaker 1: be shifted towards the red, so far towards the red 647 00:32:57,400 --> 00:33:01,120 Speaker 1: that they're essentially invisible. Like, take a visible light photon 648 00:33:01,160 --> 00:33:02,880 Speaker 1: that has a wavelength of you know, a few d 649 00:33:03,120 --> 00:33:07,840 Speaker 1: nimes and stretch that thing out past infrared, out past radio, 650 00:33:08,160 --> 00:33:09,920 Speaker 1: so it has like a wavelength you know, like the 651 00:33:09,960 --> 00:33:11,960 Speaker 1: size of the galaxy, or maybe a little smaller. That 652 00:33:12,000 --> 00:33:14,160 Speaker 1: would be a photon that's so big it would be 653 00:33:14,200 --> 00:33:17,680 Speaker 1: almost invisible. And so this would look like a black hole. Wow, 654 00:33:17,800 --> 00:33:21,200 Speaker 1: photon the size of a galaxy. That's wild. Well, let's 655 00:33:21,240 --> 00:33:24,000 Speaker 1: get into why we think these dark stars might be 656 00:33:24,280 --> 00:33:29,040 Speaker 1: real and whether or not they actually maybe supplanted black 657 00:33:29,080 --> 00:33:32,520 Speaker 1: holes and make them not real. But first let's take 658 00:33:32,560 --> 00:33:47,760 Speaker 1: another quick break. All right, we're talking about dark stars 659 00:33:47,800 --> 00:33:50,680 Speaker 1: and whether the things that we call black holes are 660 00:33:50,720 --> 00:33:52,960 Speaker 1: actually maybe not black holes, and maybe there are these 661 00:33:53,320 --> 00:33:57,160 Speaker 1: dark stars, and so we talked about what those are. Now, Daniel, 662 00:33:57,160 --> 00:33:59,240 Speaker 1: why do we think that maybe black holes are not 663 00:33:59,280 --> 00:34:03,600 Speaker 1: black holes, but they're actually these so far theoretical dark stars. Yeah. Well, 664 00:34:03,600 --> 00:34:06,320 Speaker 1: one reason is that black holes are a headache. You know, 665 00:34:06,640 --> 00:34:09,400 Speaker 1: they don't really make sense. There's lots of puzzles, like 666 00:34:09,520 --> 00:34:12,960 Speaker 1: they're fascinating, they're amazing, and they're sort of a fun headache. 667 00:34:13,200 --> 00:34:15,040 Speaker 1: But you know, there's lots of things about black holes 668 00:34:15,080 --> 00:34:18,959 Speaker 1: that we don't understand, like can a singularity be real? 669 00:34:19,080 --> 00:34:22,160 Speaker 1: Is that something which actually exists in our universe? You know, 670 00:34:22,480 --> 00:34:25,799 Speaker 1: as we said, general relativity predicts that singularities are real, 671 00:34:25,840 --> 00:34:28,560 Speaker 1: but quantum mechanics says they can't exist. And so we've 672 00:34:28,600 --> 00:34:33,040 Speaker 1: long struggled to understand that contradiction. And so this is 673 00:34:33,040 --> 00:34:35,440 Speaker 1: sort of like a way around this to say, like, oh, well, 674 00:34:35,560 --> 00:34:37,839 Speaker 1: maybe they just never happened and so we don't have 675 00:34:37,920 --> 00:34:41,640 Speaker 1: to explain them. So would this supplant even like the 676 00:34:41,680 --> 00:34:44,400 Speaker 1: black holes we think are at the center of galaxies, 677 00:34:44,520 --> 00:34:47,000 Speaker 1: Like could those supermassive black holes in the center of 678 00:34:47,040 --> 00:34:50,120 Speaker 1: galaxies that we know are humongous, could at those actually 679 00:34:50,160 --> 00:34:52,640 Speaker 1: be dark stars? Or are we only talking about the 680 00:34:52,680 --> 00:34:54,839 Speaker 1: smaller black holes. Now we're talking about all of them, 681 00:34:54,880 --> 00:34:56,719 Speaker 1: so we could supplant all of them, and that You 682 00:34:56,760 --> 00:34:59,040 Speaker 1: asked a question before the break about the X rays, 683 00:34:59,120 --> 00:35:00,920 Speaker 1: like how do we ling the X rays and the 684 00:35:00,920 --> 00:35:04,000 Speaker 1: other radiation because the supermassive black holes at the center 685 00:35:04,000 --> 00:35:06,960 Speaker 1: of our galaxy. You know, from the actual black hole, 686 00:35:07,239 --> 00:35:10,200 Speaker 1: there's no light right there black but around them are 687 00:35:10,239 --> 00:35:13,520 Speaker 1: these crazy accretion disks of hot gas that are emitting 688 00:35:13,680 --> 00:35:16,799 Speaker 1: X rays and other very high energy radiation. But that's 689 00:35:16,840 --> 00:35:18,880 Speaker 1: just from the gravity of the object. And so a 690 00:35:18,960 --> 00:35:21,799 Speaker 1: dark star with the same gravity as a black hole, 691 00:35:21,840 --> 00:35:24,520 Speaker 1: but without the actual singularity in the event horizon would 692 00:35:24,520 --> 00:35:27,880 Speaker 1: have the same gravitational impact on nearby stuff, heating it 693 00:35:27,960 --> 00:35:31,000 Speaker 1: up and swirling it around and generating that same radiation. 694 00:35:31,520 --> 00:35:34,160 Speaker 1: So yeah, you could have a huge dark star at 695 00:35:34,200 --> 00:35:36,840 Speaker 1: the center of our galaxy that's like in the middle 696 00:35:36,840 --> 00:35:40,600 Speaker 1: of a billion or trillion year collapse and rebounds out, 697 00:35:41,000 --> 00:35:43,759 Speaker 1: but it looks to us like a black hole. I 698 00:35:43,760 --> 00:35:46,640 Speaker 1: feel like you're kind of saying that maybe black holes 699 00:35:46,760 --> 00:35:49,799 Speaker 1: in themselves are impossible, Like maybe it's impossible to have 700 00:35:49,840 --> 00:35:52,360 Speaker 1: a black hole, and actually, like when you try to 701 00:35:52,400 --> 00:35:54,279 Speaker 1: get a black hole, the most you get is one 702 00:35:54,280 --> 00:35:57,719 Speaker 1: of these like super compressed dark stars which are being 703 00:35:57,800 --> 00:36:02,000 Speaker 1: kind of prevented from collapse by quantum mechanics. Yeah, exactly. 704 00:36:02,080 --> 00:36:04,719 Speaker 1: And so maybe the reason that black holes make no 705 00:36:04,840 --> 00:36:08,760 Speaker 1: sense theoretically and inconsistent with quantum mechanics is because quantum 706 00:36:08,760 --> 00:36:11,880 Speaker 1: mechanics prevents them from happening. Right, If the universe really 707 00:36:11,920 --> 00:36:14,719 Speaker 1: does follow these rules of the uncertainty principle, then that's 708 00:36:14,719 --> 00:36:18,560 Speaker 1: inconsistent with singularities, and so maybe the uncertainty principle prevents 709 00:36:18,600 --> 00:36:21,160 Speaker 1: the singularity from ever forming. Oh man, I feel like 710 00:36:21,160 --> 00:36:23,120 Speaker 1: you just blew my mind if you had how many 711 00:36:23,160 --> 00:36:25,480 Speaker 1: podcasts about black holes and now you tell me like, 712 00:36:25,520 --> 00:36:29,200 Speaker 1: maybe they're not actually real, Like maybe they're impossible. Yeah, 713 00:36:29,360 --> 00:36:32,319 Speaker 1: and in some sense, like coming up with this other 714 00:36:32,400 --> 00:36:35,439 Speaker 1: explanation for them solves all these other problems that black 715 00:36:35,440 --> 00:36:38,280 Speaker 1: holes bring with them. Right, we've had multiple episodes about 716 00:36:38,280 --> 00:36:41,480 Speaker 1: like the black hole information paradox. We know the quantum 717 00:36:41,480 --> 00:36:44,719 Speaker 1: information is not destroyed, So what happens when things fall 718 00:36:44,760 --> 00:36:47,399 Speaker 1: into a black hole? What happens to their information when 719 00:36:47,400 --> 00:36:50,040 Speaker 1: the black hole eventually evaporates, We don't know. It's not 720 00:36:50,160 --> 00:36:52,560 Speaker 1: something that makes any sense to us, and we can't 721 00:36:52,600 --> 00:36:56,239 Speaker 1: explain because we have no good theory of quantum gravity 722 00:36:56,280 --> 00:36:59,560 Speaker 1: that tells us what happens when there is gravity between 723 00:36:59,680 --> 00:37:02,279 Speaker 1: part of goals. And so maybe the solution of that 724 00:37:02,400 --> 00:37:05,120 Speaker 1: is just scratch black holes from the list of things 725 00:37:05,120 --> 00:37:07,239 Speaker 1: we want to explain, right, we don't need to get 726 00:37:07,239 --> 00:37:10,160 Speaker 1: about it, you know, like never mind, you know these 727 00:37:10,239 --> 00:37:14,879 Speaker 1: things we've been talking about forever. Uh, whoops, never mind, 728 00:37:15,320 --> 00:37:18,759 Speaker 1: it's actually not possible. Yeah, it's really fun idea, you know, 729 00:37:18,800 --> 00:37:20,920 Speaker 1: like take something off your to do list by erasing 730 00:37:20,960 --> 00:37:24,759 Speaker 1: it instead of doing it. I gotta clean the toilet. No, 731 00:37:25,040 --> 00:37:28,040 Speaker 1: toilets don't exist. Done with that, Yeah, you're gonna have 732 00:37:28,360 --> 00:37:32,040 Speaker 1: other problems if you think toilets don't exists. But the 733 00:37:32,120 --> 00:37:35,040 Speaker 1: cool thing about dark stars is not only do they 734 00:37:35,080 --> 00:37:37,960 Speaker 1: get rid of this thorny problem of black holes, but 735 00:37:38,080 --> 00:37:41,000 Speaker 1: they could explain other mysteries of the universe that are 736 00:37:41,040 --> 00:37:44,720 Speaker 1: out there. Yeah, other dark and mysterious stuff. Right. Yeah. 737 00:37:45,120 --> 00:37:48,040 Speaker 1: For example, we've long wondered, you know, what is the 738 00:37:48,080 --> 00:37:51,200 Speaker 1: stuff out there in the universe that's creating all this 739 00:37:51,400 --> 00:37:54,960 Speaker 1: gravity that seems to be holding the galaxy together, some 740 00:37:55,080 --> 00:37:57,680 Speaker 1: weird new kind of matter that we don't know what 741 00:37:57,719 --> 00:38:00,319 Speaker 1: it is and we can't see it, but it has gravity, 742 00:38:00,360 --> 00:38:02,960 Speaker 1: and it's affected the structure of the universe, and it 743 00:38:02,960 --> 00:38:05,640 Speaker 1: affects how galaxies spin, and it seems to be everywhere 744 00:38:05,640 --> 00:38:07,759 Speaker 1: and really important, and it's more of it. And then 745 00:38:07,800 --> 00:38:09,680 Speaker 1: there is a normal matter, but we don't really know 746 00:38:09,760 --> 00:38:11,919 Speaker 1: what it is and we haven't been able to see 747 00:38:11,920 --> 00:38:14,400 Speaker 1: it or interact with it or detected. So this stuff 748 00:38:14,480 --> 00:38:16,920 Speaker 1: dark matter. We have a long list of candidates for 749 00:38:16,960 --> 00:38:20,000 Speaker 1: what it might be, but now because of dark stars, 750 00:38:20,040 --> 00:38:22,680 Speaker 1: we have sort of a new candidate that appears on 751 00:38:22,719 --> 00:38:26,000 Speaker 1: that list, and that's these crazy long wavelength photons. So 752 00:38:26,120 --> 00:38:28,920 Speaker 1: you're saying that the light from these the dark stars 753 00:38:29,120 --> 00:38:30,680 Speaker 1: is what could be dark k matter or are you 754 00:38:30,719 --> 00:38:33,520 Speaker 1: saying that maybe the universe is like riddled and filled 755 00:38:33,560 --> 00:38:36,160 Speaker 1: with tiny dark stars everywhere. You know, it's the light 756 00:38:36,280 --> 00:38:39,120 Speaker 1: and the radiation from these dark stars. So these dark 757 00:38:39,160 --> 00:38:42,000 Speaker 1: stars look a lot like black holes, but they do 758 00:38:42,120 --> 00:38:44,759 Speaker 1: give off some light, but that light is invisible to 759 00:38:44,880 --> 00:38:48,640 Speaker 1: us because it's so low frequency, and that light itself 760 00:38:48,800 --> 00:38:51,160 Speaker 1: might be the dark matter. It could be that there's 761 00:38:51,200 --> 00:38:53,480 Speaker 1: so much of it out there that the light itself 762 00:38:53,560 --> 00:38:57,440 Speaker 1: is helping curve space. Because remember photons have no mass, 763 00:38:57,440 --> 00:39:01,320 Speaker 1: but in general relativity, space bends in the presence of energy, 764 00:39:01,400 --> 00:39:04,480 Speaker 1: not just mass, so photons can contribute to that. And 765 00:39:04,560 --> 00:39:08,960 Speaker 1: so these things can contribute photons or even gravitons that 766 00:39:09,000 --> 00:39:11,919 Speaker 1: are hard to detect, but overall, having lots and lots 767 00:39:11,920 --> 00:39:14,400 Speaker 1: and lots of them around, they can bend the shape 768 00:39:14,400 --> 00:39:16,840 Speaker 1: of space and exactly the way dark matter does. I 769 00:39:16,880 --> 00:39:19,240 Speaker 1: feel like now you're saying that maybe dark matter doesn't exist, 770 00:39:19,280 --> 00:39:23,799 Speaker 1: and really it's just dark light. Dark stars emitting dark 771 00:39:23,840 --> 00:39:27,240 Speaker 1: photons could explain everything. But wouldn't black holes also emit 772 00:39:27,360 --> 00:39:29,960 Speaker 1: you know, these dark photons, if black holes existed. But 773 00:39:30,040 --> 00:39:32,760 Speaker 1: black holes don't emit anything, right, I mean, black holes 774 00:39:32,800 --> 00:39:35,960 Speaker 1: don't emit light. The stuff around them emits light. But 775 00:39:36,080 --> 00:39:38,200 Speaker 1: this is the one thing that would be different between 776 00:39:38,239 --> 00:39:40,719 Speaker 1: black holes and dark stars. That these dark stars, because 777 00:39:40,760 --> 00:39:43,160 Speaker 1: they don't have event horizons, they do emit light, and 778 00:39:43,239 --> 00:39:46,480 Speaker 1: that light is crazy stretch to low frequencies by the 779 00:39:46,520 --> 00:39:51,040 Speaker 1: gravitational strength of the dark star. Can we measure these 780 00:39:51,120 --> 00:39:54,120 Speaker 1: long wavelength light? Can we have a detector to see 781 00:39:54,120 --> 00:39:56,799 Speaker 1: if they're there? It's very difficult to interact with something 782 00:39:56,840 --> 00:39:59,719 Speaker 1: that's such a long wavelength. They're basically just ignores you. 783 00:40:00,000 --> 00:40:02,560 Speaker 1: That's why, for example, we do radio astronomy because radio 784 00:40:02,560 --> 00:40:05,200 Speaker 1: waves can go through like clouds of gas and dust 785 00:40:05,280 --> 00:40:06,759 Speaker 1: and tell us what's going on in the center of 786 00:40:06,800 --> 00:40:08,680 Speaker 1: the galaxy. Because to them, the clouds of gas and 787 00:40:08,760 --> 00:40:11,719 Speaker 1: dust are like nothing, and so it's very, very difficult 788 00:40:11,760 --> 00:40:14,440 Speaker 1: to interact with those photons. You need a detector like 789 00:40:14,520 --> 00:40:17,560 Speaker 1: the size of the galaxy almost in order to interact 790 00:40:17,560 --> 00:40:19,280 Speaker 1: with them. I feel like you're telling me, like, maybe 791 00:40:19,680 --> 00:40:22,440 Speaker 1: you know that dark matter halo that we know is 792 00:40:22,760 --> 00:40:24,880 Speaker 1: or a cloud that is sort of covering our galaxy. 793 00:40:24,920 --> 00:40:26,839 Speaker 1: Maybe it's just it's not dark matter. May it's just 794 00:40:26,960 --> 00:40:32,920 Speaker 1: like one giant photon, like one one ginormous photon, you know, 795 00:40:33,000 --> 00:40:35,960 Speaker 1: confusing us. That'd be hilarious if it's like, Hi, I'm Bob, 796 00:40:35,960 --> 00:40:37,840 Speaker 1: I'm a photon and I've been the dark matter of 797 00:40:37,880 --> 00:40:43,280 Speaker 1: the whole time. Yeah, there you go. We found our culprit. 798 00:40:43,440 --> 00:40:45,560 Speaker 1: Why didn't you introduce yourself in Act one? Man? Why 799 00:40:45,560 --> 00:40:47,520 Speaker 1: did you wait on to Act three? That's just bad 800 00:40:47,560 --> 00:40:50,279 Speaker 1: mystery writing. Well, that's really interesting to think about. But 801 00:40:50,320 --> 00:40:54,040 Speaker 1: you know, photons are quantized and really really low frequency 802 00:40:54,080 --> 00:40:56,640 Speaker 1: photon would not have that much energy right, because the 803 00:40:56,760 --> 00:40:59,200 Speaker 1: energy the photon depends on its wavelength. So in order 804 00:40:59,239 --> 00:41:01,080 Speaker 1: to explain the dark no matter, you need a lot 805 00:41:01,160 --> 00:41:03,120 Speaker 1: of these photons. They have to be Bob and like 806 00:41:03,400 --> 00:41:05,560 Speaker 1: ten to the twenty seven of his friends. I think, 807 00:41:05,760 --> 00:41:08,799 Speaker 1: kind of like the nuta book, they're fooling ice cream 808 00:41:08,800 --> 00:41:11,160 Speaker 1: flavor of the galaxy. Yeah, and you know, this is 809 00:41:11,200 --> 00:41:13,879 Speaker 1: a fun theory for people to think about, like could 810 00:41:13,920 --> 00:41:16,720 Speaker 1: this be becauld it really exists out there in the universe. 811 00:41:16,800 --> 00:41:19,200 Speaker 1: What are ways we could separate them from black holes 812 00:41:19,200 --> 00:41:21,960 Speaker 1: that we could actually detect. But it's a new area. 813 00:41:22,000 --> 00:41:24,279 Speaker 1: People are playing with it, you know. Carlo Rovelli wrote 814 00:41:24,280 --> 00:41:26,480 Speaker 1: a fun paper about them. I read a few papers 815 00:41:26,480 --> 00:41:28,840 Speaker 1: on this topic. It's still something that's in people's minds. 816 00:41:29,040 --> 00:41:30,880 Speaker 1: I see, like we don't know if it's even possible 817 00:41:30,920 --> 00:41:33,920 Speaker 1: to have these dark stars or whether they would just 818 00:41:33,960 --> 00:41:36,040 Speaker 1: collapse into the black hole. Yeah, the signs of them 819 00:41:36,080 --> 00:41:38,600 Speaker 1: is still very new and tentative, and people are doing 820 00:41:38,640 --> 00:41:41,719 Speaker 1: calculations and making all sort of assumptions and disagreeing with 821 00:41:41,719 --> 00:41:43,960 Speaker 1: each other about what these things might look like. It's 822 00:41:44,000 --> 00:41:46,239 Speaker 1: really at the forefront of knowledge. But you know, black 823 00:41:46,280 --> 00:41:48,600 Speaker 1: holes were at the forefront of knowledge. For decades before 824 00:41:48,600 --> 00:41:51,239 Speaker 1: we understood really what they would mean and what they 825 00:41:51,239 --> 00:41:53,640 Speaker 1: would look like in the universe, and so it might 826 00:41:53,680 --> 00:41:55,680 Speaker 1: just take a little while for sort of like people 827 00:41:55,719 --> 00:41:58,480 Speaker 1: to digest this stuff intellectually and figure out how to 828 00:41:58,520 --> 00:42:00,640 Speaker 1: look for them correctly. Well, it's at that picture that 829 00:42:00,640 --> 00:42:02,400 Speaker 1: we took up the black hole last year or two 830 00:42:02,480 --> 00:42:04,719 Speaker 1: years ago. It was pretty convincing. But now when I 831 00:42:04,760 --> 00:42:07,320 Speaker 1: look at it, and maybe I'll imagine a little tiny 832 00:42:07,360 --> 00:42:10,680 Speaker 1: bob in the middle there laughing at us and twitterling. 833 00:42:10,760 --> 00:42:13,160 Speaker 1: It's a mustache, yeh, exactly. Maybe it has a totally 834 00:42:13,239 --> 00:42:17,319 Speaker 1: jet black mustache and you can't see it, and it's 835 00:42:17,400 --> 00:42:21,680 Speaker 1: laughing at you and admitting dark matter. That's crazy. All right, Well, 836 00:42:21,719 --> 00:42:25,640 Speaker 1: I guess once more the universe is full of potential surprises. 837 00:42:25,840 --> 00:42:28,960 Speaker 1: And I guess the main lesson here is don't trust physicists. 838 00:42:29,000 --> 00:42:34,239 Speaker 1: You know, maybe we're talking about this whole podcast. No, 839 00:42:34,400 --> 00:42:38,040 Speaker 1: the lesson is fund physicists to think of crazy ideas, 840 00:42:38,160 --> 00:42:40,200 Speaker 1: because they might find stuff that's actually out there, and 841 00:42:40,200 --> 00:42:42,480 Speaker 1: then they might come up with even better explanations to 842 00:42:42,520 --> 00:42:46,280 Speaker 1: describe what you see. We definitely need creative brain story 843 00:42:46,400 --> 00:42:49,000 Speaker 1: about how the universe works. That's a good positive spin. 844 00:42:49,440 --> 00:42:51,680 Speaker 1: All right, well, we hope you enjoyed that. Thanks for 845 00:42:51,760 --> 00:43:02,279 Speaker 1: joining us, see you next time. Thanks for listening, and 846 00:43:02,320 --> 00:43:05,080 Speaker 1: remember that Daniel and Jorge Explain the Universe is a 847 00:43:05,080 --> 00:43:08,520 Speaker 1: production of I Heart Radio. Or more podcast from my 848 00:43:08,640 --> 00:43:12,239 Speaker 1: heart Radio. Visit the I heart Radio app, Apple Podcasts, 849 00:43:12,320 --> 00:43:14,680 Speaker 1: or wherever you listen to your favorite shows.