1 00:00:08,360 --> 00:00:10,280 Speaker 1: All right, Hey, Daniel, are you ready to record? 2 00:00:10,600 --> 00:00:12,639 Speaker 2: Oh wait just a minute, I lost something. 3 00:00:13,000 --> 00:00:14,360 Speaker 1: Well what are you looking for? 4 00:00:14,640 --> 00:00:17,040 Speaker 2: Oh, you know, nothing important, just this black hole? 5 00:00:18,079 --> 00:00:20,480 Speaker 1: A black hole. How can you lose a black hole? 6 00:00:20,760 --> 00:00:22,320 Speaker 2: I don't know, but it really sucks. 7 00:00:23,120 --> 00:00:25,680 Speaker 1: Yeah, you have a massive problem there to be. Your 8 00:00:25,680 --> 00:00:28,240 Speaker 1: parents teach you to always take care of your black holes. 9 00:00:28,360 --> 00:00:30,240 Speaker 2: I seem to just be accreting problems. 10 00:00:45,640 --> 00:00:45,720 Speaker 3: Hi. 11 00:00:45,760 --> 00:00:48,320 Speaker 1: I'm Joorne Mack, cartoonist. I'm the author of Oliver's Great 12 00:00:48,360 --> 00:00:49,120 Speaker 1: Big Universe. 13 00:00:49,479 --> 00:00:52,400 Speaker 2: Hi I'm Daniel. I'm a particle physicist and a professor 14 00:00:52,440 --> 00:00:55,480 Speaker 2: at UC Irvine, and I really do want a personal 15 00:00:55,560 --> 00:00:56,279 Speaker 2: black hole. 16 00:00:56,240 --> 00:00:58,440 Speaker 1: Like your own little black hole in your backyard or 17 00:00:58,480 --> 00:00:59,000 Speaker 1: like in your. 18 00:00:58,840 --> 00:01:02,280 Speaker 2: Pocket, like in a lab at work, in a basement, 19 00:01:02,720 --> 00:01:05,760 Speaker 2: behind lots of shielding, et cetera. But yeah, I'd love 20 00:01:05,800 --> 00:01:07,240 Speaker 2: to have a black hole to study. 21 00:01:07,600 --> 00:01:10,080 Speaker 1: M wouldn't the shielding fall into the black hole? 22 00:01:11,720 --> 00:01:14,080 Speaker 2: You know? If you build a small enough black hole, 23 00:01:14,520 --> 00:01:16,080 Speaker 2: then it would actually be stable. 24 00:01:16,240 --> 00:01:18,440 Speaker 1: Wouldn't it evaporate eventually? But do you have to keep 25 00:01:18,480 --> 00:01:18,920 Speaker 1: feeding it? 26 00:01:19,080 --> 00:01:21,399 Speaker 2: Yeah? Exactly. You could keep feeding it at just the 27 00:01:21,440 --> 00:01:24,080 Speaker 2: same rate it was evaporating, and you could keep it 28 00:01:24,120 --> 00:01:25,880 Speaker 2: there safe and sustainable. 29 00:01:26,000 --> 00:01:28,440 Speaker 1: Hmmm, I wonder how stable that would be. It might 30 00:01:28,440 --> 00:01:30,800 Speaker 1: turn it to runaway process by accident. 31 00:01:30,959 --> 00:01:33,360 Speaker 2: Oh yeah, I mean you might accidentally, like consume the 32 00:01:33,360 --> 00:01:36,640 Speaker 2: whole Earth, et cetera, dot dot dot. But uh huh, 33 00:01:38,200 --> 00:01:39,800 Speaker 2: you might learn a lot along the way. 34 00:01:39,880 --> 00:01:42,080 Speaker 1: That would be a problem for the rest of us. 35 00:01:42,080 --> 00:01:44,160 Speaker 2: You wouldn't worry about it afterwards, I mean, you wouldn't 36 00:01:44,160 --> 00:01:44,600 Speaker 2: be around. 37 00:01:45,000 --> 00:01:46,920 Speaker 1: I'm pretty sure we would learn not to give you 38 00:01:46,920 --> 00:01:47,520 Speaker 1: a black hole. 39 00:01:48,360 --> 00:01:50,440 Speaker 2: Yeah. Well, it's a one time mistake, that's for sure. 40 00:01:51,560 --> 00:01:54,040 Speaker 1: But anyways, welcome for a podcast Daniel and Jorge Explain 41 00:01:54,120 --> 00:01:57,040 Speaker 1: the Universe, a production of iHeartRadio. 42 00:01:56,480 --> 00:01:59,680 Speaker 2: In which we tap into your desire to understand the 43 00:01:59,720 --> 00:02:03,680 Speaker 2: whole universe, your absolutely desperate need to know how the 44 00:02:03,800 --> 00:02:07,240 Speaker 2: universe actually works. What's out there, how does it function, 45 00:02:07,360 --> 00:02:11,120 Speaker 2: what rules is it following, what are its fundamental basic bits, 46 00:02:11,400 --> 00:02:14,360 Speaker 2: and what's controlling all of it? Is there reason and 47 00:02:14,400 --> 00:02:16,760 Speaker 2: in order to the universe or is it all just 48 00:02:16,919 --> 00:02:18,560 Speaker 2: a big chaotic swirl. 49 00:02:18,720 --> 00:02:20,760 Speaker 1: That's right. We like to talk about everything that's happening 50 00:02:20,800 --> 00:02:23,400 Speaker 1: in the universe before you lose your mind or any 51 00:02:23,600 --> 00:02:26,520 Speaker 1: giant gravitational objects out there in space. 52 00:02:27,919 --> 00:02:29,679 Speaker 2: I think I'm more likely to lose a black hole 53 00:02:29,720 --> 00:02:30,520 Speaker 2: than lose my mind. 54 00:02:30,800 --> 00:02:32,320 Speaker 1: I think if you own a black hole, you might 55 00:02:32,360 --> 00:02:36,239 Speaker 1: have already lost your mind. Guilty, or maybe the rest 56 00:02:36,240 --> 00:02:38,080 Speaker 1: of us lost our minds for letting you have a 57 00:02:38,080 --> 00:02:40,600 Speaker 1: black hole that might destroy the Earth. 58 00:02:41,800 --> 00:02:43,960 Speaker 2: Sometimes I do think people were crazy to give me 59 00:02:44,000 --> 00:02:44,480 Speaker 2: this job. 60 00:02:44,560 --> 00:02:46,400 Speaker 1: But that is an interesting scenario to have, like a 61 00:02:46,440 --> 00:02:48,800 Speaker 1: personal black hole in a lab to study. But what 62 00:02:48,800 --> 00:02:50,840 Speaker 1: happens if you have to move labs? How can you 63 00:02:50,880 --> 00:02:51,720 Speaker 1: move a black hole? 64 00:02:51,800 --> 00:02:53,760 Speaker 2: A black hole is just a thing, so you can 65 00:02:53,800 --> 00:02:56,280 Speaker 2: move it the way you move everything else, you know, But. 66 00:02:56,240 --> 00:02:58,639 Speaker 1: How do you push it? You can't push it, can you? 67 00:02:58,639 --> 00:02:59,480 Speaker 1: You can't pick it up? 68 00:03:00,840 --> 00:03:03,079 Speaker 2: I mean, I wouldn't put your hand in it, But 69 00:03:03,320 --> 00:03:06,040 Speaker 2: it has massed so you could attract it with other gravity. 70 00:03:06,120 --> 00:03:06,679 Speaker 2: I suppose. 71 00:03:07,000 --> 00:03:11,280 Speaker 1: I suppose it makes you think about this a little 72 00:03:11,280 --> 00:03:13,600 Speaker 1: bit more before creating a black hole here on Earth. 73 00:03:13,639 --> 00:03:15,480 Speaker 2: I mean, if you have the capacity to create a 74 00:03:15,480 --> 00:03:17,640 Speaker 2: black hole in a lab, then you could just stop 75 00:03:17,680 --> 00:03:20,160 Speaker 2: feeding it, let it evaporate away, and then create a 76 00:03:20,200 --> 00:03:21,080 Speaker 2: new one somewhere else. 77 00:03:21,800 --> 00:03:24,840 Speaker 1: But would it be sort of a potentially unstable or 78 00:03:24,880 --> 00:03:28,320 Speaker 1: are black holes relatively stable? Like if a p fill 79 00:03:28,360 --> 00:03:30,320 Speaker 1: in or a speck of dust. Would it be too 80 00:03:30,400 --> 00:03:32,160 Speaker 1: much and then suddenly we'll grow out of control. 81 00:03:32,280 --> 00:03:35,440 Speaker 2: They're definitely unstable. So you'd be writing the knife's edge 82 00:03:35,480 --> 00:03:39,120 Speaker 2: between learning something about the universe and destroying all of humanity. 83 00:03:39,560 --> 00:03:42,600 Speaker 2: It'd be a very delicate balance, because, as you're saying, 84 00:03:42,600 --> 00:03:44,760 Speaker 2: it grows too big, then it has more gravity. Then 85 00:03:44,800 --> 00:03:47,520 Speaker 2: it can grow bigger faster, and then it'll have even 86 00:03:47,520 --> 00:03:49,960 Speaker 2: more gravity. Dot dot dot, and there's no way to 87 00:03:49,960 --> 00:03:50,560 Speaker 2: turn it off. 88 00:03:51,200 --> 00:03:57,400 Speaker 1: Yeaha YadA YadA, we all die horrible dead. I don't 89 00:03:57,440 --> 00:03:58,760 Speaker 1: like this, physicist, YadA YadA. 90 00:03:58,800 --> 00:04:00,640 Speaker 2: The problem is that there's no way to shrink a 91 00:04:00,680 --> 00:04:04,360 Speaker 2: black hole except for letting it evaporate, and that's a 92 00:04:04,520 --> 00:04:07,560 Speaker 2: very slow process. Especially as the black hole gets bigger, 93 00:04:07,800 --> 00:04:11,000 Speaker 2: it evaporates less and less, so once it starts to 94 00:04:11,040 --> 00:04:13,400 Speaker 2: run away, there's like no safety valve. There's no like 95 00:04:13,520 --> 00:04:15,800 Speaker 2: black hole extinguisher you can spray on it. 96 00:04:16,120 --> 00:04:20,240 Speaker 1: M I guess you can't shoot it with like antimatter. 97 00:04:20,279 --> 00:04:21,120 Speaker 1: That wouldn't help, right. 98 00:04:21,279 --> 00:04:24,280 Speaker 2: Antimatter wouldn't just make it stronger. Nuclear weapons just make 99 00:04:24,320 --> 00:04:27,720 Speaker 2: it stronger. More black holes just make it stronger. Any 100 00:04:27,839 --> 00:04:29,919 Speaker 2: kind of energy just makes it stronger. 101 00:04:29,960 --> 00:04:31,880 Speaker 1: So that's like, it'd be a bad idea to try 102 00:04:31,880 --> 00:04:34,360 Speaker 1: to create black holes here on Earth, right, Like, who 103 00:04:34,400 --> 00:04:36,680 Speaker 1: would do that? That's insane? 104 00:04:38,040 --> 00:04:40,440 Speaker 2: Well, we are literally trying to create black holes at 105 00:04:40,440 --> 00:04:41,680 Speaker 2: the Large Hadron Collider. 106 00:04:42,560 --> 00:04:45,120 Speaker 1: I know, That's why I bring it up. But it 107 00:04:45,200 --> 00:04:46,360 Speaker 1: sounds like a terrible idea. 108 00:04:47,640 --> 00:04:49,480 Speaker 2: Think of all we could learn, man. 109 00:04:50,000 --> 00:04:52,560 Speaker 1: Yeah, again, we could learn not to trust physicists too 110 00:04:53,400 --> 00:04:54,960 Speaker 1: experiment with black holes here on Earth. 111 00:04:55,960 --> 00:04:58,640 Speaker 2: Maybe, But you know, black holes are such amazing mysteries. 112 00:04:58,640 --> 00:05:01,280 Speaker 2: We don't know how they form, know what's inside them. 113 00:05:01,360 --> 00:05:03,920 Speaker 2: We don't know how gravity and relativity come together to 114 00:05:03,920 --> 00:05:06,039 Speaker 2: make it all make sense, or if it does even 115 00:05:06,080 --> 00:05:08,919 Speaker 2: make sense, or if behind that veil the universe is 116 00:05:09,000 --> 00:05:12,479 Speaker 2: like broken and chaotic in some weird way. But the 117 00:05:12,480 --> 00:05:15,440 Speaker 2: most frustrating thing is that they're all so far away. 118 00:05:16,040 --> 00:05:18,560 Speaker 2: There are no black holes nearby for us to study. 119 00:05:18,800 --> 00:05:19,640 Speaker 1: And that's a bad thing. 120 00:05:20,200 --> 00:05:22,160 Speaker 2: That's a bad thing if you want to learn about that. 121 00:05:22,240 --> 00:05:26,479 Speaker 1: Yes, I get it, they're very mysterious and interesting. They 122 00:05:26,560 --> 00:05:29,880 Speaker 1: might potentially unlock the mysteries of the universe. But maybe 123 00:05:29,880 --> 00:05:33,039 Speaker 1: we should send you there instead of trying to bring 124 00:05:33,080 --> 00:05:33,520 Speaker 1: them here. 125 00:05:34,560 --> 00:05:36,120 Speaker 2: Maybe I'll send the probe. Haven't that? 126 00:05:36,360 --> 00:05:39,080 Speaker 1: Oh there you go, all right, we'll compromise. But yeah, 127 00:05:39,160 --> 00:05:42,000 Speaker 1: black holes are super mysterious and as you said, maybe 128 00:05:42,160 --> 00:05:45,040 Speaker 1: hold the key to the universe, and sometimes they can 129 00:05:45,040 --> 00:05:45,559 Speaker 1: get lost. 130 00:05:45,600 --> 00:05:50,159 Speaker 2: Apparently, maybe some aliens out there are creating black holes 131 00:05:50,200 --> 00:05:52,760 Speaker 2: and then accidentally losing them. 132 00:05:52,800 --> 00:05:54,799 Speaker 1: So today on the podcast, we'll be digging the question. 133 00:06:00,000 --> 00:06:03,960 Speaker 1: So what happened to M thirty three's central black hole? 134 00:06:04,520 --> 00:06:06,480 Speaker 1: Now there's a lot of numbers here. M thirty three 135 00:06:06,600 --> 00:06:09,720 Speaker 1: central black hole is that someone's black holes. 136 00:06:11,720 --> 00:06:14,280 Speaker 2: I don't know who made that black hole or where 137 00:06:14,279 --> 00:06:16,919 Speaker 2: they put it or why they lost it. But M 138 00:06:16,960 --> 00:06:21,880 Speaker 2: thirty three is a galaxy fairly nearby one without a 139 00:06:21,960 --> 00:06:24,080 Speaker 2: black hole seen at its center? 140 00:06:25,279 --> 00:06:27,200 Speaker 1: Is there evidence that it had a black hole before? 141 00:06:27,360 --> 00:06:29,880 Speaker 2: There is no evidence that it ever had a black hole, 142 00:06:30,520 --> 00:06:32,440 Speaker 2: And so that's sort of the question is like, how 143 00:06:32,480 --> 00:06:34,520 Speaker 2: do you form a galaxy without a black hole? Or 144 00:06:34,560 --> 00:06:36,440 Speaker 2: did you form it and lose it? How is that 145 00:06:36,520 --> 00:06:38,600 Speaker 2: even possible? What's going on? 146 00:06:39,960 --> 00:06:42,560 Speaker 1: So maybe the real question is like, why doesn't M 147 00:06:42,640 --> 00:06:44,880 Speaker 1: thirty three have a black hole in the middle. 148 00:06:44,960 --> 00:06:46,159 Speaker 2: Yeah, that's another way to say it. 149 00:06:46,160 --> 00:06:48,120 Speaker 1: It seems like me it's the more a great way 150 00:06:48,160 --> 00:06:50,360 Speaker 1: to say it, Like if I never had a million 151 00:06:50,400 --> 00:06:52,440 Speaker 1: dollars and I went around asking what happened to my 152 00:06:52,520 --> 00:06:53,239 Speaker 1: million dollars? 153 00:06:53,720 --> 00:06:56,120 Speaker 2: Might get some weird looks with like everybody in your 154 00:06:56,160 --> 00:06:59,200 Speaker 2: neighborhood wears pants, and then you walk around without pants, 155 00:06:59,240 --> 00:07:02,240 Speaker 2: people might say, hey, what happened to his pants? And 156 00:07:02,320 --> 00:07:05,160 Speaker 2: saying hey, I never wore pants isn't really an explanation, 157 00:07:06,360 --> 00:07:07,080 Speaker 2: all right, Well. 158 00:07:07,000 --> 00:07:10,600 Speaker 1: To dig into this interesting mystery, and as usual, Daniel 159 00:07:10,920 --> 00:07:13,559 Speaker 1: went out there asking people if they knew what happened 160 00:07:13,600 --> 00:07:15,600 Speaker 1: to M three three's central black hole. 161 00:07:15,960 --> 00:07:18,280 Speaker 2: I didn't ask anybody if they wear pants, and that's 162 00:07:18,280 --> 00:07:20,880 Speaker 2: a piece of information they can keep to themselves. And 163 00:07:20,960 --> 00:07:23,720 Speaker 2: you don't have to wear pants to participate in this 164 00:07:23,840 --> 00:07:27,200 Speaker 2: part of the podcast. It all happens online via email, 165 00:07:27,440 --> 00:07:29,800 Speaker 2: So if you would like to give answers to future 166 00:07:29,880 --> 00:07:33,720 Speaker 2: physics questions, please write to me two questions at Danielandjorge 167 00:07:33,800 --> 00:07:36,040 Speaker 2: dot com whether or not you have a black hole 168 00:07:36,360 --> 00:07:36,880 Speaker 2: or pants. 169 00:07:37,200 --> 00:07:39,480 Speaker 1: So think about it for a second. What do you 170 00:07:39,480 --> 00:07:42,280 Speaker 1: think happened to M three three's central black hole? 171 00:07:42,520 --> 00:07:45,160 Speaker 3: Did something happen to M thirty three central black hole? 172 00:07:46,200 --> 00:07:49,760 Speaker 3: I don't know. I can only assume that it's either 173 00:07:49,800 --> 00:07:54,280 Speaker 3: dissipated or it's getting bigger. I don't think you know, 174 00:07:54,320 --> 00:07:58,200 Speaker 3: because over time, don't they give off hawking radiation? Right, 175 00:07:58,320 --> 00:08:04,080 Speaker 3: so over galactic periods of time then it would disperse. 176 00:08:05,160 --> 00:08:08,520 Speaker 3: But you make it sound like it's happened more suddenly 177 00:08:08,560 --> 00:08:10,080 Speaker 3: than that, because I don't think we'd be able to 178 00:08:10,120 --> 00:08:12,840 Speaker 3: observe that, because you know that's over billions of years. 179 00:08:12,880 --> 00:08:17,920 Speaker 3: So I can maybe assume that something spectacular has happened. 180 00:08:18,000 --> 00:08:21,040 Speaker 3: Maybe it's like swallowed something huge and it's it's maybe 181 00:08:21,320 --> 00:08:23,520 Speaker 3: I don't know, the accretion disk is glowing more than 182 00:08:23,560 --> 00:08:24,880 Speaker 3: it would normally. 183 00:08:25,000 --> 00:08:25,440 Speaker 2: I don't know. 184 00:08:25,920 --> 00:08:29,920 Speaker 1: Did it get absorbed by another black hole and produce 185 00:08:30,120 --> 00:08:34,000 Speaker 1: gravitational waves? I'm going to guess something epic happened to it. 186 00:08:34,000 --> 00:08:36,920 Speaker 1: Did it collapse and disappear? 187 00:08:37,440 --> 00:08:37,800 Speaker 2: All right? 188 00:08:37,800 --> 00:08:40,240 Speaker 1: Well, now, Daniel, you've made me wonder whether these people 189 00:08:40,280 --> 00:08:42,600 Speaker 1: that were telling us their answer if they had pants 190 00:08:42,640 --> 00:08:43,000 Speaker 1: on or not. 191 00:08:45,400 --> 00:08:47,280 Speaker 2: That's the detail you're wondering, right, you have no idea 192 00:08:47,320 --> 00:08:49,840 Speaker 2: what they look like where they live, but now you're 193 00:08:49,880 --> 00:08:51,560 Speaker 2: curious about whether they're wearing pants. 194 00:08:51,600 --> 00:08:53,240 Speaker 1: Well, I'm wondering if you gave him permission to do 195 00:08:53,240 --> 00:08:56,800 Speaker 1: it pantless, and whether they followed your instruction. 196 00:08:57,800 --> 00:09:00,000 Speaker 2: I mean I didn't tell them to take off their pants. 197 00:09:00,320 --> 00:09:01,480 Speaker 2: That would have been kind of weird. 198 00:09:03,400 --> 00:09:08,800 Speaker 1: Yeah, what kind of business are you running here? The 199 00:09:08,840 --> 00:09:10,120 Speaker 1: Pantless Businesses Club? 200 00:09:11,240 --> 00:09:14,079 Speaker 2: It's pants optional, not pantless. It's very different. 201 00:09:14,520 --> 00:09:16,120 Speaker 1: Everyone has to wear kilt. 202 00:09:17,440 --> 00:09:19,160 Speaker 2: Where whatever you're like, we don't care. 203 00:09:22,520 --> 00:09:25,000 Speaker 1: Wait, are you saying you can be naked? Is this 204 00:09:25,200 --> 00:09:27,720 Speaker 1: like the clothing optional Physicist Club? 205 00:09:27,840 --> 00:09:31,000 Speaker 2: Absolutely? Where would ever be like? Wear nothing where? Everything 206 00:09:31,520 --> 00:09:34,000 Speaker 2: doesn't matter. It's all online doesn't. 207 00:09:35,120 --> 00:09:36,920 Speaker 1: To get to wear your wear your curiosity. 208 00:09:36,960 --> 00:09:39,640 Speaker 2: I guess you go wear your curiosity on your sleeve 209 00:09:40,000 --> 00:09:41,320 Speaker 2: whether or not you can have a sleep. 210 00:09:42,440 --> 00:09:45,360 Speaker 1: I feel like you have low standards for your online friends, Daniel. 211 00:09:46,280 --> 00:09:48,360 Speaker 2: I'm just focusing on most important. 212 00:09:49,160 --> 00:09:52,400 Speaker 1: Like can you tweet? Then you're my friend clothes. I 213 00:09:52,480 --> 00:09:53,440 Speaker 1: need to know nothing else. 214 00:09:55,040 --> 00:09:56,760 Speaker 2: What was that about tweeting? 215 00:09:57,040 --> 00:09:59,160 Speaker 1: You just have to tweet. I don't care about anything else, Bud. 216 00:09:59,200 --> 00:10:01,240 Speaker 2: You think I'm friends with everybody on. 217 00:10:01,200 --> 00:10:02,760 Speaker 1: Twitter, Well not everyone on Twitter. 218 00:10:02,920 --> 00:10:05,600 Speaker 2: I do like interacting with our listeners on Twitter. If 219 00:10:05,640 --> 00:10:08,240 Speaker 2: you like being on Twitter, come and tweet us a question. 220 00:10:08,400 --> 00:10:09,360 Speaker 2: We will answer it. 221 00:10:09,440 --> 00:10:11,720 Speaker 1: Well, nobody seemed to have an idea of what happened 222 00:10:11,720 --> 00:10:15,319 Speaker 1: to this galaxies central black hole. In fact, people seem 223 00:10:15,360 --> 00:10:17,280 Speaker 1: to be sort of alarmed by your question. You're like, what, 224 00:10:17,280 --> 00:10:18,559 Speaker 1: what did something happen. 225 00:10:20,840 --> 00:10:23,800 Speaker 2: Exactly? And you're the number one suspect. Do you have 226 00:10:23,840 --> 00:10:26,120 Speaker 2: an alibi for where you were when this. 227 00:10:26,040 --> 00:10:30,360 Speaker 1: Black hole disappeared? I was out buying pants apparently. 228 00:10:31,440 --> 00:10:33,000 Speaker 2: Where you were donating all your pants. 229 00:10:33,000 --> 00:10:36,320 Speaker 1: It sounds like, yes, I was having a grase cell 230 00:10:36,679 --> 00:10:39,440 Speaker 1: for all my pants. I was helping you look for 231 00:10:39,480 --> 00:10:41,000 Speaker 1: your black hole. That's what I was doing. 232 00:10:42,440 --> 00:10:44,320 Speaker 2: Story keeps changing pretty ciss. 233 00:10:44,880 --> 00:10:47,320 Speaker 1: Well, let's jump right into this, Daniel. So why are 234 00:10:47,320 --> 00:10:50,200 Speaker 1: we talking about black holes? What are they? And how 235 00:10:50,240 --> 00:10:51,680 Speaker 1: can we miss them or lose them? 236 00:10:51,760 --> 00:10:54,119 Speaker 2: So we talk about black holes a lot on the podcast, 237 00:10:54,200 --> 00:10:57,240 Speaker 2: and people who listen regularly will know that black holes 238 00:10:57,240 --> 00:11:01,320 Speaker 2: are this theoretical concept of prediction of general relativity that 239 00:11:01,360 --> 00:11:04,160 Speaker 2: if you have enough mass or just energy in a 240 00:11:04,200 --> 00:11:08,760 Speaker 2: localized spot, it will bend space so dramatically that no 241 00:11:08,880 --> 00:11:11,640 Speaker 2: information will be able to leave past an event horizon. 242 00:11:11,880 --> 00:11:14,240 Speaker 2: We don't actually know what's going on beyond the event horizon, 243 00:11:14,480 --> 00:11:17,800 Speaker 2: but general relativity predicts that there's a singularity, a dot 244 00:11:17,840 --> 00:11:21,960 Speaker 2: of infinitely dense matter curving space so intensely that even 245 00:11:22,000 --> 00:11:25,960 Speaker 2: photons cannot escape. We've seen black holes out there in 246 00:11:26,000 --> 00:11:29,280 Speaker 2: the wild, or things we identify with black holes. We 247 00:11:29,320 --> 00:11:32,440 Speaker 2: can't actually verify that they have this event horizon. But 248 00:11:32,520 --> 00:11:36,280 Speaker 2: there are some very dense, very massive objects that seem 249 00:11:36,320 --> 00:11:39,400 Speaker 2: to give off no radiation, and black holes are the 250 00:11:39,400 --> 00:11:44,040 Speaker 2: most popular suspects to explain those weird dense objects. M. 251 00:11:44,280 --> 00:11:46,040 Speaker 1: Yeah, we've talked about this a little bit before that. 252 00:11:46,480 --> 00:11:48,880 Speaker 1: You know, there are pictures online of what physicists think 253 00:11:48,960 --> 00:11:51,160 Speaker 1: might be black holes, and they look like black holes, right, Like, 254 00:11:51,200 --> 00:11:53,720 Speaker 1: if you look at these images, they're just black circles. 255 00:11:54,280 --> 00:11:57,319 Speaker 1: But as you said, maybe these could not be black holes. 256 00:11:57,440 --> 00:11:59,600 Speaker 2: Yeah, they actually kind of look like Krispy Kreme donuts 257 00:12:00,000 --> 00:12:02,680 Speaker 2: because what you're looking at in the image is this halo, 258 00:12:02,960 --> 00:12:06,960 Speaker 2: this accretion disk, this blob of gas swirling around the 259 00:12:07,000 --> 00:12:09,160 Speaker 2: black hole at the center of it. You're right, there's 260 00:12:09,200 --> 00:12:11,400 Speaker 2: this black circle, and they say, oh, that's the black hole, 261 00:12:11,880 --> 00:12:14,240 Speaker 2: but it's more like an absence of information that tells 262 00:12:14,280 --> 00:12:17,000 Speaker 2: you something we don't actually know what is there. It 263 00:12:17,040 --> 00:12:19,200 Speaker 2: could be a black hole, it could be a dark star, 264 00:12:19,679 --> 00:12:21,960 Speaker 2: it could be a fuzzball. It could be lots of 265 00:12:22,000 --> 00:12:25,240 Speaker 2: other things that don't emit light and are super duper dense. 266 00:12:26,280 --> 00:12:28,080 Speaker 1: Now, how do you get a black hole or how 267 00:12:28,120 --> 00:12:29,880 Speaker 1: would you get a black hole if they existed? 268 00:12:30,840 --> 00:12:34,040 Speaker 2: Black Holes out in the universe come in two different varieties, 269 00:12:34,040 --> 00:12:37,280 Speaker 2: which is kind of weird. There's like the smaller black hole, 270 00:12:37,720 --> 00:12:41,480 Speaker 2: which forms when a star finishes its life. A star, 271 00:12:41,559 --> 00:12:44,760 Speaker 2: when it's burning, the fusion the radiation puffs it out 272 00:12:44,800 --> 00:12:48,480 Speaker 2: and keeps it from collapsing gravitationally into a black hole. 273 00:12:48,960 --> 00:12:51,440 Speaker 2: But when it's done burning, when it's no longer producing 274 00:12:51,480 --> 00:12:54,880 Speaker 2: that radiation, gravity eventually wins, and if the star had 275 00:12:55,000 --> 00:12:58,760 Speaker 2: enough stuff to begin with, it collapses into a black hole. 276 00:12:59,320 --> 00:13:02,439 Speaker 2: These are typical like ten times up to thirty, forty 277 00:13:02,520 --> 00:13:05,720 Speaker 2: fifty eighty times the mass of our sun, So we 278 00:13:05,760 --> 00:13:08,880 Speaker 2: call those stellar black holes, and those sound pretty big, 279 00:13:08,960 --> 00:13:11,000 Speaker 2: like eighty times the mass of our Sun is a 280 00:13:11,000 --> 00:13:14,120 Speaker 2: lot of stuff, but that's actually small compared to the 281 00:13:14,200 --> 00:13:16,680 Speaker 2: other category of black holes we see out there in 282 00:13:16,679 --> 00:13:17,280 Speaker 2: the universe. 283 00:13:17,559 --> 00:13:20,479 Speaker 1: Right. These are called super massive black holes. 284 00:13:20,200 --> 00:13:24,040 Speaker 2: Exactly, and these are only found at the hearts of galaxies, 285 00:13:24,280 --> 00:13:26,839 Speaker 2: a place where there's a lot of matter already very 286 00:13:26,920 --> 00:13:30,920 Speaker 2: very dense. These super massive black holes can be tens 287 00:13:31,000 --> 00:13:35,160 Speaker 2: of thousands of solar masses up to billions of solar masses, 288 00:13:35,360 --> 00:13:39,480 Speaker 2: really just incredible concentrations of matter in the universe. 289 00:13:40,200 --> 00:13:42,080 Speaker 1: So you have these two kinds of black holes, and 290 00:13:42,240 --> 00:13:45,400 Speaker 1: is there like small ones kind of and super duper 291 00:13:45,480 --> 00:13:47,280 Speaker 1: big ones. Is there nothing in between them? 292 00:13:47,360 --> 00:13:51,400 Speaker 2: In between? There's this category called intermediate mass black holes, 293 00:13:51,720 --> 00:13:54,280 Speaker 2: and it's a category with a name, but we don't 294 00:13:54,280 --> 00:13:57,640 Speaker 2: have any observations there. It's kind of a mystery. We 295 00:13:57,679 --> 00:13:59,920 Speaker 2: did a podcast a couple years ago about where are 296 00:14:00,120 --> 00:14:03,480 Speaker 2: all the intermediate mass black holes? Part of the mystery 297 00:14:03,520 --> 00:14:06,040 Speaker 2: of super massive black holes. We don't know how they formed, 298 00:14:06,080 --> 00:14:08,839 Speaker 2: how they got so big. It'd be interesting to see 299 00:14:08,880 --> 00:14:11,800 Speaker 2: intermediate mass black holes because they might just be like 300 00:14:12,160 --> 00:14:16,040 Speaker 2: baby versions of super massive black holes. So it's part 301 00:14:16,080 --> 00:14:18,640 Speaker 2: of the mystery of how these really really big ones formed, 302 00:14:18,840 --> 00:14:21,160 Speaker 2: why we don't see them forming, why we don't see 303 00:14:21,160 --> 00:14:24,320 Speaker 2: intermediate mass ones instead of a whole spectrum. We have 304 00:14:24,360 --> 00:14:25,560 Speaker 2: these two populations. 305 00:14:26,520 --> 00:14:28,840 Speaker 1: Now, the ones we've actually sort of seen are the 306 00:14:28,920 --> 00:14:32,360 Speaker 1: super massive black hole kind, right, and the pictures they 307 00:14:32,400 --> 00:14:35,120 Speaker 1: found a couple of years ago that they took were 308 00:14:35,160 --> 00:14:37,920 Speaker 1: of super massive black holes, because we don't have pictures 309 00:14:37,920 --> 00:14:40,160 Speaker 1: of the smaller black holes, do we. 310 00:14:39,760 --> 00:14:42,000 Speaker 2: We don't the images that we're talking about. We only 311 00:14:42,000 --> 00:14:44,720 Speaker 2: have images of the Milky Way and this messy eighty 312 00:14:44,800 --> 00:14:47,960 Speaker 2: seven galaxy. Those are the two black holes that we 313 00:14:48,000 --> 00:14:50,680 Speaker 2: have these images of where you can go online and 314 00:14:50,720 --> 00:14:53,520 Speaker 2: see a picture of the accretion disk, etc. Those are 315 00:14:53,640 --> 00:14:56,720 Speaker 2: very very difficult to take. Those pictures requires a lot 316 00:14:56,720 --> 00:15:00,400 Speaker 2: of observation from many different telescopes, all coordinated, sort of 317 00:15:00,440 --> 00:15:03,760 Speaker 2: piece that together over several years, and also requires that 318 00:15:03,800 --> 00:15:06,320 Speaker 2: the galaxy be like close enough that we can see it, 319 00:15:06,360 --> 00:15:08,440 Speaker 2: but tilted in just the right way so that we 320 00:15:08,440 --> 00:15:11,400 Speaker 2: can look at the black hole, et cetera. So we've 321 00:15:11,440 --> 00:15:13,960 Speaker 2: only done that for a couple but we have identified 322 00:15:14,240 --> 00:15:18,440 Speaker 2: super massive black holes in a couple hundred other galaxies, 323 00:15:18,840 --> 00:15:21,320 Speaker 2: not directly with images, but with other techniques. 324 00:15:21,600 --> 00:15:23,320 Speaker 1: Right, that's what I mean. Like the ones that you 325 00:15:23,400 --> 00:15:26,520 Speaker 1: see in the pictures that are online, those are super 326 00:15:26,520 --> 00:15:29,040 Speaker 1: massive black holes, right, the two that you mentioned, And 327 00:15:29,080 --> 00:15:31,160 Speaker 1: we don't actually have pictures of even the small ones. 328 00:15:31,560 --> 00:15:34,880 Speaker 1: We just know they're out there from their gravity. 329 00:15:34,520 --> 00:15:36,840 Speaker 2: That's right. We see them out there because of their gravity. 330 00:15:36,840 --> 00:15:38,720 Speaker 2: For example, You'll see a star and you'll see it 331 00:15:38,800 --> 00:15:42,200 Speaker 2: orbiting something invisible, and you can calculate with the mass 332 00:15:42,200 --> 00:15:43,960 Speaker 2: of that thing is. You can see how close that 333 00:15:44,040 --> 00:15:46,480 Speaker 2: star gets to it, and that tells you how big 334 00:15:46,520 --> 00:15:49,080 Speaker 2: it can't be, like that's a limit on the size 335 00:15:49,120 --> 00:15:51,920 Speaker 2: of the thing. That's how black holes were first discovered, 336 00:15:52,280 --> 00:15:55,040 Speaker 2: is that we saw these things orbiting what looked like nothing, 337 00:15:55,600 --> 00:15:57,600 Speaker 2: and then we could deduce the mass of the object 338 00:15:57,640 --> 00:15:59,520 Speaker 2: and get an idea of the size of it, and 339 00:15:59,560 --> 00:16:01,880 Speaker 2: from that to douce the existence of the black hole. 340 00:16:02,360 --> 00:16:05,120 Speaker 2: That's the kind of indirect evidence we have for stellar 341 00:16:05,160 --> 00:16:07,560 Speaker 2: mass black holes. And we can do the same kind 342 00:16:07,600 --> 00:16:10,160 Speaker 2: of thing to try to look for super massive black 343 00:16:10,200 --> 00:16:11,680 Speaker 2: holes and the hearts of galaxies. 344 00:16:11,920 --> 00:16:14,280 Speaker 1: Right Like, if you see some stars swirling around but 345 00:16:14,320 --> 00:16:16,720 Speaker 1: you don't see anything bright in the middle, then you 346 00:16:16,800 --> 00:16:19,120 Speaker 1: sort of assumed that there is a super massive black 347 00:16:19,160 --> 00:16:20,160 Speaker 1: hole there. 348 00:16:20,400 --> 00:16:23,280 Speaker 2: Yeah, exactly. And in the case of our own Milky Way, 349 00:16:23,800 --> 00:16:27,160 Speaker 2: we've pointed telescopes at the heart of the galaxy and 350 00:16:27,160 --> 00:16:30,000 Speaker 2: gotten a lot of details. We followed individual stars as 351 00:16:30,000 --> 00:16:33,560 Speaker 2: they come very close to Sagittarius, a star the black 352 00:16:33,560 --> 00:16:36,360 Speaker 2: hole at the center of our galaxy, and we can 353 00:16:36,440 --> 00:16:39,440 Speaker 2: measure its mass as those stars swing around, because we 354 00:16:39,560 --> 00:16:43,080 Speaker 2: understand the gravitational effect, and when a cloud of dust 355 00:16:43,200 --> 00:16:46,120 Speaker 2: passes nearby, and we can see how big is this thing? 356 00:16:46,160 --> 00:16:48,440 Speaker 2: How close can you get to it without falling in? 357 00:16:49,240 --> 00:16:51,240 Speaker 2: There was actually Nobel Prize given in the last few 358 00:16:51,320 --> 00:16:54,320 Speaker 2: years for these detailed studies of the super massive black 359 00:16:54,320 --> 00:16:57,080 Speaker 2: hole the heart of our galaxy. So even before we 360 00:16:57,160 --> 00:16:59,480 Speaker 2: had that image, we had a pretty good idea for 361 00:16:59,520 --> 00:17:02,080 Speaker 2: the mass and the radius of this thing, just by 362 00:17:02,080 --> 00:17:05,680 Speaker 2: studying the stellar dynamics the stars whizzing around it, from 363 00:17:05,680 --> 00:17:09,359 Speaker 2: which we're inferring the gravitational effect of that black hole. 364 00:17:09,359 --> 00:17:11,679 Speaker 1: Right, And you can sort of infer or deduce that 365 00:17:11,880 --> 00:17:15,600 Speaker 1: it's something super compact and dense, right, Like, that's a 366 00:17:15,640 --> 00:17:19,560 Speaker 1: really strong gravitational effect around the stars that are swirling 367 00:17:19,560 --> 00:17:22,040 Speaker 1: around it. But when you look there, you not only 368 00:17:22,080 --> 00:17:24,840 Speaker 1: not see anything bright, but you also just see kind 369 00:17:24,840 --> 00:17:27,720 Speaker 1: of the space, the space behind there, right, So whatever's 370 00:17:27,720 --> 00:17:30,080 Speaker 1: there is super massive and it doesn't take up a 371 00:17:30,119 --> 00:17:30,679 Speaker 1: lot of room. 372 00:17:30,600 --> 00:17:33,239 Speaker 2: Yeah, exactly. And then you look at your menu of like, well, 373 00:17:33,320 --> 00:17:36,160 Speaker 2: what out in nature can do that? What can be 374 00:17:36,200 --> 00:17:39,359 Speaker 2: so massive and so small and the only sort of 375 00:17:39,400 --> 00:17:42,520 Speaker 2: widely accepted thing is a black hole. There are other 376 00:17:42,720 --> 00:17:45,400 Speaker 2: speculative ideas for what might be able to do that 377 00:17:45,680 --> 00:17:48,200 Speaker 2: we talked about on the podcast other times, dark stars 378 00:17:48,240 --> 00:17:50,919 Speaker 2: and fuzzballs that could potentially also do that, And there 379 00:17:50,920 --> 00:17:53,919 Speaker 2: are various theories of quantum gravity to predict things. But 380 00:17:54,000 --> 00:17:56,919 Speaker 2: the black holes these days like the vanilla explanation for 381 00:17:57,040 --> 00:17:57,960 Speaker 2: what could be doing it. 382 00:17:58,320 --> 00:18:00,560 Speaker 1: You mean the chocolate explanation, the. 383 00:18:00,600 --> 00:18:02,960 Speaker 2: Dark chocolate explanation exactly. 384 00:18:03,400 --> 00:18:05,560 Speaker 1: But I guess what makes it a better theory than 385 00:18:05,560 --> 00:18:07,560 Speaker 1: some of these other ideas that you talked about, like 386 00:18:07,560 --> 00:18:09,439 Speaker 1: why is this one preferred? Why is this one vanilla? 387 00:18:09,560 --> 00:18:12,879 Speaker 2: It's vanilla because it doesn't require any new physics. You 388 00:18:12,880 --> 00:18:15,000 Speaker 2: don't have to add to our theories of physics to 389 00:18:15,040 --> 00:18:17,080 Speaker 2: explain it. You just have to rely on good old 390 00:18:17,119 --> 00:18:21,240 Speaker 2: general relativity, which predicts these black holes and very accurately 391 00:18:21,280 --> 00:18:24,560 Speaker 2: describes their radiation and everything we see from the outside. 392 00:18:25,280 --> 00:18:28,320 Speaker 2: So from the outside, general relativity works perfectly to describe 393 00:18:28,320 --> 00:18:30,800 Speaker 2: these objects. It's just when you're wondering about, like what's 394 00:18:30,880 --> 00:18:34,080 Speaker 2: inside of it, that you might need some new physics theories, 395 00:18:34,119 --> 00:18:37,439 Speaker 2: some quantum gravity to explain the combination of very intense 396 00:18:37,480 --> 00:18:40,440 Speaker 2: gravity and very very small objects to account for the 397 00:18:40,520 --> 00:18:43,400 Speaker 2: quantum nature that we know has to play a role 398 00:18:43,440 --> 00:18:44,679 Speaker 2: inside these black holes. 399 00:18:46,440 --> 00:18:48,040 Speaker 1: Now, that's how we can see the one here in 400 00:18:48,080 --> 00:18:51,400 Speaker 1: the Milky Way galaxy, the black hole center of our galaxy. 401 00:18:51,440 --> 00:18:53,600 Speaker 1: But in other galaxies, I mean, they're so far away 402 00:18:53,600 --> 00:18:57,080 Speaker 1: you can't really see individual stars swirling around, right. 403 00:18:57,119 --> 00:19:00,760 Speaker 2: That's right. You can't track individual stars in other galaxies. 404 00:19:00,760 --> 00:19:03,520 Speaker 2: We don't have telescopes that can do that. But you 405 00:19:03,640 --> 00:19:06,159 Speaker 2: can build up an idea of the stellar dynamics the 406 00:19:06,200 --> 00:19:10,879 Speaker 2: velocities for nearby galaxies by looking at the general brightness 407 00:19:10,960 --> 00:19:13,080 Speaker 2: near the center of the galaxy. We can get a 408 00:19:13,119 --> 00:19:15,719 Speaker 2: sense for the velocity of those stars by looking at 409 00:19:15,720 --> 00:19:18,000 Speaker 2: their spectra, like how is the light from those stars 410 00:19:18,040 --> 00:19:21,200 Speaker 2: red shifted? And piecing it together with a whole lot 411 00:19:21,200 --> 00:19:23,760 Speaker 2: of computing power, we can get a model for what 412 00:19:23,880 --> 00:19:26,879 Speaker 2: is the velocity of the stars near the center of 413 00:19:26,880 --> 00:19:30,360 Speaker 2: the galaxy, and from that we can deduce how massive 414 00:19:30,480 --> 00:19:33,479 Speaker 2: a black hole has to be there to explain the 415 00:19:33,520 --> 00:19:35,200 Speaker 2: stellar velocities we see. 416 00:19:35,600 --> 00:19:38,199 Speaker 1: Oh interesting, It's like if there are a bunch of 417 00:19:38,240 --> 00:19:41,040 Speaker 1: stars swirling at the center of a faraway galaxy. You 418 00:19:41,080 --> 00:19:43,320 Speaker 1: can't see them individual stars, but you can sort of 419 00:19:43,480 --> 00:19:46,600 Speaker 1: get a far away view of the churn that's happening 420 00:19:46,720 --> 00:19:49,000 Speaker 1: there in that galaxy. Right, Like, if there's a lot 421 00:19:49,000 --> 00:19:52,040 Speaker 1: of stars moving really fast, then their light is going 422 00:19:52,080 --> 00:19:54,960 Speaker 1: to be red shifted as the stars move away from you, 423 00:19:55,440 --> 00:19:59,040 Speaker 1: and blue shit as the stars move towards you. And 424 00:19:59,080 --> 00:20:01,080 Speaker 1: so the more red blue light that you see coming 425 00:20:01,080 --> 00:20:02,800 Speaker 1: from the center with the galaxy means there's a lot 426 00:20:02,840 --> 00:20:03,960 Speaker 1: of movement going on. 427 00:20:03,920 --> 00:20:07,040 Speaker 2: There, exactly. We can tell the difference between a galaxy 428 00:20:07,080 --> 00:20:10,040 Speaker 2: that has a really fast churn with massive stars and 429 00:20:10,080 --> 00:20:12,240 Speaker 2: a galaxy it's more like a lazy river, you know, 430 00:20:12,240 --> 00:20:14,840 Speaker 2: where things are just like bobbing along slowly and sedately. 431 00:20:15,520 --> 00:20:17,720 Speaker 1: So you see a galaxy where the center is moving 432 00:20:17,800 --> 00:20:19,840 Speaker 1: a lot, there's a lot of turn in there, but 433 00:20:19,960 --> 00:20:22,760 Speaker 1: the center's not super bright, then there must be something 434 00:20:22,840 --> 00:20:25,840 Speaker 1: really compact, something really dark in there that is probably 435 00:20:26,000 --> 00:20:27,760 Speaker 1: a super massive black hole exactly. 436 00:20:27,840 --> 00:20:30,520 Speaker 2: And it's very similar to how we infer the existence 437 00:20:30,600 --> 00:20:33,600 Speaker 2: of dark matter. You know, this is an indirect measurement 438 00:20:33,680 --> 00:20:36,359 Speaker 2: of mass. You say, well, these things are moving, and 439 00:20:36,359 --> 00:20:38,840 Speaker 2: therefore there has to be gravity to hold them in place. 440 00:20:39,240 --> 00:20:41,600 Speaker 2: Why they're not being flung out of the galaxy. The 441 00:20:41,640 --> 00:20:44,919 Speaker 2: answer is there's some gravity there that's holding it in place, 442 00:20:45,359 --> 00:20:47,919 Speaker 2: and that gravity should be explained by mass, So we 443 00:20:47,960 --> 00:20:51,320 Speaker 2: can measure how much mass is needed to explain these 444 00:20:51,480 --> 00:20:54,879 Speaker 2: stellar motions. This is how dark matter was discovered. We 445 00:20:55,040 --> 00:20:57,560 Speaker 2: noticed that you couldn't add enough mass throughout the whole 446 00:20:57,600 --> 00:21:00,440 Speaker 2: galaxy to explain the motion of the stars. And here 447 00:21:00,480 --> 00:21:04,000 Speaker 2: we're pinpointing the very very center of the galaxy. 448 00:21:04,400 --> 00:21:07,320 Speaker 1: Yeah, and so it teams that most galaxies have a 449 00:21:07,359 --> 00:21:09,480 Speaker 1: super massive black hole in the middle, but not all 450 00:21:09,480 --> 00:21:12,400 Speaker 1: of them. Some of them seem to be missing they're 451 00:21:12,440 --> 00:21:15,720 Speaker 1: black holes. So let's dig into this mystery for the 452 00:21:15,720 --> 00:21:19,399 Speaker 1: galaxy M thirty three. But first let's take a quick break. 453 00:21:31,680 --> 00:21:35,560 Speaker 1: All right, we're trying to find Daniel's missing black hole. Now, Daniel, 454 00:21:35,560 --> 00:21:38,879 Speaker 1: can a black hole technically be missing? Like, isn't a 455 00:21:38,920 --> 00:21:40,760 Speaker 1: hole the missing of something? 456 00:21:42,880 --> 00:21:45,480 Speaker 2: There's a chunk of space missing. Every black hole is 457 00:21:45,520 --> 00:21:47,440 Speaker 2: a missing piece of space, I suppose. 458 00:21:48,920 --> 00:21:51,080 Speaker 1: Well, it's like a hole in your backyard. A hole 459 00:21:51,160 --> 00:21:53,280 Speaker 1: is the absence of some dirt. So really, how can 460 00:21:53,320 --> 00:21:54,960 Speaker 1: you be missing the absence of some dirt? 461 00:21:57,080 --> 00:21:59,160 Speaker 2: Yeah, it's tempting to think of a black hole as 462 00:21:59,160 --> 00:22:01,720 Speaker 2: a whole, as like a missing piece of the universe, 463 00:22:02,119 --> 00:22:04,520 Speaker 2: and in some sense they are. There's an event horizon there. 464 00:22:05,119 --> 00:22:07,440 Speaker 2: Whatever is behind it is not really part of our 465 00:22:07,600 --> 00:22:10,960 Speaker 2: universe because it can't interact with us. On the other hand, 466 00:22:11,040 --> 00:22:13,960 Speaker 2: it is part of our space because it's bending our space, 467 00:22:14,040 --> 00:22:18,359 Speaker 2: it's causing distortions, it generates gravitational waves, it changes the 468 00:22:18,400 --> 00:22:21,360 Speaker 2: trajectories of things that are outside of it. So it's 469 00:22:21,400 --> 00:22:24,840 Speaker 2: definitely a thing, right, it has an influence on our universe. 470 00:22:25,840 --> 00:22:27,959 Speaker 1: I see, it's not a chunk of space that's missing. 471 00:22:28,560 --> 00:22:30,960 Speaker 1: It's more of a whole, as in like a place 472 00:22:31,040 --> 00:22:33,639 Speaker 1: where things can fall into and never come out. Yeah, 473 00:22:33,680 --> 00:22:35,760 Speaker 1: but at the center of it, or in general, it 474 00:22:35,840 --> 00:22:39,160 Speaker 1: has mass and a position and it can move around. 475 00:22:39,280 --> 00:22:39,840 Speaker 1: It's a thing. 476 00:22:40,240 --> 00:22:43,320 Speaker 2: Yeah, it's a thing. It's something, and they're very powerful, 477 00:22:43,400 --> 00:22:46,320 Speaker 2: these black holes at the hearts of galaxies. It's hard 478 00:22:46,359 --> 00:22:49,720 Speaker 2: to really wrap your mind around how massive these things are. 479 00:22:50,320 --> 00:22:55,080 Speaker 2: Billions of stars all compressed down into tiny areas, and 480 00:22:55,119 --> 00:22:57,080 Speaker 2: it makes you wonder, like what's going on at the 481 00:22:57,119 --> 00:22:59,200 Speaker 2: particle level and what it would be like to be there. 482 00:23:00,320 --> 00:23:02,480 Speaker 1: Yeah, it must be pretty intense to be a near 483 00:23:02,480 --> 00:23:05,240 Speaker 1: a black hole. But as we're talking about, like how 484 00:23:05,280 --> 00:23:07,320 Speaker 1: we see them, and so sometimes you can see them 485 00:23:07,359 --> 00:23:10,080 Speaker 1: from their gravitational effect. But sometimes there are black holes 486 00:23:10,119 --> 00:23:11,320 Speaker 1: that kind of glow, right. 487 00:23:11,480 --> 00:23:14,760 Speaker 2: Yeah, some black holes that we call quasars, are actually 488 00:23:14,880 --> 00:23:17,639 Speaker 2: very very bright. If they have a strong magnetic field 489 00:23:17,800 --> 00:23:19,920 Speaker 2: and they're feeding a lot, like a lot of matter 490 00:23:20,000 --> 00:23:22,879 Speaker 2: is falling into them. Sometimes not all of that matter 491 00:23:22,920 --> 00:23:25,920 Speaker 2: actually ends up in the black hole. The magnetic field 492 00:23:26,040 --> 00:23:28,960 Speaker 2: can tend to spiral them around and then shut them 493 00:23:29,040 --> 00:23:32,960 Speaker 2: up and down towards the north and south magnetic poles, 494 00:23:32,960 --> 00:23:36,120 Speaker 2: sort of like the inverse of the Aurora borealis. There's 495 00:23:36,160 --> 00:23:39,240 Speaker 2: a bunch of particles coming from space and then spiraling 496 00:23:39,280 --> 00:23:42,720 Speaker 2: around magnetic fields to the north pole before falling into 497 00:23:42,760 --> 00:23:45,919 Speaker 2: the planet. These guys spiral along the magnetic field but 498 00:23:45,960 --> 00:23:49,639 Speaker 2: then get shunted up in these very powerful beams north 499 00:23:49,720 --> 00:23:52,320 Speaker 2: and south. And so a black hole the center of 500 00:23:52,320 --> 00:23:56,440 Speaker 2: a galaxy can create these incredibly bright particle jets, which 501 00:23:56,480 --> 00:23:58,440 Speaker 2: you can see from across the galaxy. 502 00:23:59,080 --> 00:24:01,439 Speaker 1: They're super bright, right, They're sort of brighter than the 503 00:24:01,440 --> 00:24:04,840 Speaker 1: whole galaxy if it happens to point in your direction exactly. 504 00:24:04,880 --> 00:24:07,320 Speaker 2: They're incredibly bright, so bright that for a long time 505 00:24:07,320 --> 00:24:11,399 Speaker 2: people didn't even really believe they could be galaxies because 506 00:24:11,400 --> 00:24:13,879 Speaker 2: they were visibly very bright, and we knew they were 507 00:24:14,000 --> 00:24:16,639 Speaker 2: very very far away, which means that like at their source, 508 00:24:17,000 --> 00:24:19,920 Speaker 2: they were mind bogglingly bright. When people first wrote down 509 00:24:19,920 --> 00:24:22,320 Speaker 2: the numbers and were like, what, this doesn't make sense. 510 00:24:22,320 --> 00:24:24,919 Speaker 2: How could anything be that bright? It would take an 511 00:24:24,960 --> 00:24:27,879 Speaker 2: incredible amount of power to accelerate those particles and then 512 00:24:27,920 --> 00:24:30,639 Speaker 2: shunt them up north and south, and in the end 513 00:24:30,680 --> 00:24:32,560 Speaker 2: of black hole is the only thing we know that 514 00:24:32,640 --> 00:24:34,840 Speaker 2: can explain that that has that kind of power. 515 00:24:35,000 --> 00:24:36,520 Speaker 1: But you can only see them if they're kind of 516 00:24:36,520 --> 00:24:39,040 Speaker 1: pointing directly at you, right. It's sort of like a 517 00:24:39,080 --> 00:24:42,040 Speaker 1: flashlight far away flashlight has pointing at you. Otherwise you're 518 00:24:42,080 --> 00:24:43,639 Speaker 1: probably not going to see it in the middle of 519 00:24:43,680 --> 00:24:44,080 Speaker 1: the night. 520 00:24:44,160 --> 00:24:46,960 Speaker 2: Yeah, exactly. They need to be pointed at you, and 521 00:24:47,080 --> 00:24:49,880 Speaker 2: they need to be beaming. Not every super massive black 522 00:24:49,880 --> 00:24:52,840 Speaker 2: hole out there is a quasar. Quasars are just the 523 00:24:52,880 --> 00:24:55,480 Speaker 2: ones that happened to be feeding right now and be 524 00:24:55,640 --> 00:24:57,920 Speaker 2: very hot emitting all these X rays. 525 00:24:58,359 --> 00:25:00,280 Speaker 1: What's the percentage of super massive black hole does it 526 00:25:00,280 --> 00:25:01,040 Speaker 1: have quasars? 527 00:25:01,200 --> 00:25:03,400 Speaker 2: Quasars turned out to be quite rare. It's a smaller 528 00:25:03,440 --> 00:25:07,000 Speaker 2: percentage of galaxies, But we don't understand exactly why there's 529 00:25:07,000 --> 00:25:09,919 Speaker 2: a quasar sometimes and why there isn't, So it's not 530 00:25:10,000 --> 00:25:12,679 Speaker 2: something we've measured very very well. We haven't seen that 531 00:25:12,800 --> 00:25:15,159 Speaker 2: many quasars, so we don't have a great handle on 532 00:25:15,240 --> 00:25:18,320 Speaker 2: the fraction of galaxies that are quasars. What we do 533 00:25:18,440 --> 00:25:21,280 Speaker 2: know is that quasars were much more common earlier in 534 00:25:21,320 --> 00:25:24,760 Speaker 2: the universe. Like the quasar epic of the universe seems 535 00:25:24,800 --> 00:25:27,240 Speaker 2: to be kind of over. It seems to have peaked 536 00:25:27,320 --> 00:25:28,840 Speaker 2: like ten billion years ago. 537 00:25:28,960 --> 00:25:32,520 Speaker 1: Wait, what quasar's peak and what happens to them? 538 00:25:32,640 --> 00:25:35,119 Speaker 2: Quasar's peak? And then they fade? You know, they're not 539 00:25:35,240 --> 00:25:39,000 Speaker 2: always blasting this incredible bright light out into the universe. 540 00:25:38,680 --> 00:25:40,360 Speaker 1: Like they're run out of stuff or what like. 541 00:25:40,320 --> 00:25:42,920 Speaker 2: They just stop being quasars. You know, there's still super 542 00:25:42,960 --> 00:25:45,640 Speaker 2: massive black holes, but if they're not feeding as actively, 543 00:25:46,119 --> 00:25:49,440 Speaker 2: then they're not necessarily generating these big beams. The feeding 544 00:25:49,480 --> 00:25:51,439 Speaker 2: of a black hole is not so simple. As it 545 00:25:51,480 --> 00:25:54,040 Speaker 2: gets more powerful, the stuff around it gets hot and 546 00:25:54,080 --> 00:25:57,200 Speaker 2: creates radiation, which pushes away it's fuel, and so there's 547 00:25:57,200 --> 00:25:59,920 Speaker 2: this Eddington limit to how fast a black hole can grow. 548 00:26:00,440 --> 00:26:03,280 Speaker 2: If it grows too quickly, it can end up starving itself. 549 00:26:03,800 --> 00:26:06,000 Speaker 2: So there's a lot of complicated dynamics for how black 550 00:26:06,000 --> 00:26:06,679 Speaker 2: holes grow. 551 00:26:07,080 --> 00:26:08,840 Speaker 1: But what it means starving itself, Well, if. 552 00:26:08,760 --> 00:26:10,879 Speaker 2: You emit a lot of radiation, you can blow away 553 00:26:10,920 --> 00:26:12,919 Speaker 2: the gas that was sort of like on deck to 554 00:26:13,000 --> 00:26:13,480 Speaker 2: fall in. 555 00:26:13,760 --> 00:26:15,920 Speaker 1: So you can be a quasar that quits and you 556 00:26:16,000 --> 00:26:16,840 Speaker 1: end up being quiet. 557 00:26:17,400 --> 00:26:20,919 Speaker 2: Yeah, quixotically, yeah, exactly, And it could be that like 558 00:26:21,160 --> 00:26:23,439 Speaker 2: in billion years ago in the universe, there was just 559 00:26:23,560 --> 00:26:27,000 Speaker 2: more fuel available for these black holes to gobble, and 560 00:26:27,119 --> 00:26:29,680 Speaker 2: they ate all the easy fuel, and we're no longer 561 00:26:29,680 --> 00:26:32,720 Speaker 2: making quaisars. Like the younger galaxies one the more nearby 562 00:26:32,800 --> 00:26:35,560 Speaker 2: galaxies we don't see quasars, and those we mostly see 563 00:26:35,560 --> 00:26:38,920 Speaker 2: them in the ancient galaxies about ten billion years ago. 564 00:26:39,880 --> 00:26:41,679 Speaker 1: Now, does our milk away have a quasar in the 565 00:26:41,680 --> 00:26:44,520 Speaker 1: middle or is it just the regular super massive black hole. 566 00:26:44,680 --> 00:26:47,080 Speaker 2: Our galaxy does not have a quasar in the middle, 567 00:26:47,480 --> 00:26:49,159 Speaker 2: and it's got a black hole, but it's not like 568 00:26:49,400 --> 00:26:51,840 Speaker 2: that impressed of a black hole. There are other galaxies 569 00:26:51,880 --> 00:26:52,879 Speaker 2: with bigger black holes. 570 00:26:53,119 --> 00:26:55,320 Speaker 1: Well, as you mentioned, a lot of galaxies have super 571 00:26:55,320 --> 00:26:57,720 Speaker 1: massive black holes in the middle, but not all of them. 572 00:26:57,920 --> 00:27:02,119 Speaker 2: Right, almost every single big galaxy we've seen has a 573 00:27:02,119 --> 00:27:04,440 Speaker 2: super massive black hole in it. It's like when you're 574 00:27:04,440 --> 00:27:06,480 Speaker 2: walking around town, you're pretty sure you're going to see 575 00:27:06,520 --> 00:27:09,160 Speaker 2: everybody wearing pants or shorts or a skirt or something. 576 00:27:09,320 --> 00:27:13,240 Speaker 2: It's pretty rare to see somebody pantsless out in public. 577 00:27:13,680 --> 00:27:15,720 Speaker 2: In the same way, when we look at galaxies, like 578 00:27:15,880 --> 00:27:18,920 Speaker 2: we almost always find a super massive black hole at 579 00:27:18,920 --> 00:27:19,359 Speaker 2: their heart. 580 00:27:19,600 --> 00:27:21,880 Speaker 1: Mmm, what's the general percentage? 581 00:27:21,920 --> 00:27:23,880 Speaker 2: I guess, Well, we've only looked at like a couple 582 00:27:23,880 --> 00:27:26,280 Speaker 2: of hundred. This is not easy to do. You need 583 00:27:26,320 --> 00:27:29,040 Speaker 2: to have enough resolving power to see the stellar motion 584 00:27:29,200 --> 00:27:31,240 Speaker 2: and figure that all out. We can't do that for 585 00:27:31,359 --> 00:27:34,960 Speaker 2: very very far away galaxies. But of the couple hundred 586 00:27:35,000 --> 00:27:37,720 Speaker 2: that we've looked at, every single one has a super 587 00:27:37,760 --> 00:27:40,119 Speaker 2: massive black hole at its heart, except one that we 588 00:27:40,160 --> 00:27:43,800 Speaker 2: think was ejected in a very recent collision of two galaxies. 589 00:27:44,080 --> 00:27:46,920 Speaker 2: And then M thirty three, which doesn't have a central 590 00:27:46,960 --> 00:27:47,440 Speaker 2: black hole. 591 00:27:48,280 --> 00:27:50,200 Speaker 1: Well, we'll get to M three three a little bit later. 592 00:27:50,800 --> 00:27:52,720 Speaker 1: But I think, as you were saying, and as I 593 00:27:52,760 --> 00:27:54,760 Speaker 1: think we've talked about it before, it's kind of a 594 00:27:54,800 --> 00:27:58,600 Speaker 1: big mystery about why so many galaxies have super massive 595 00:27:58,600 --> 00:28:00,280 Speaker 1: black holes, Like where do they come from. 596 00:28:00,119 --> 00:28:02,399 Speaker 2: Exactly, and the heart of the mystery is how they 597 00:28:02,440 --> 00:28:04,879 Speaker 2: get so massive. It makes sense for there to be 598 00:28:04,920 --> 00:28:07,439 Speaker 2: a black hole at the center of the galaxy. Stuff 599 00:28:07,480 --> 00:28:09,800 Speaker 2: falls in, it gets more massive. Eventually you get a 600 00:28:09,800 --> 00:28:13,520 Speaker 2: black hole that seems obvious, but we don't understand how 601 00:28:13,560 --> 00:28:17,160 Speaker 2: they get so big. We can build models of galaxy formation. 602 00:28:17,640 --> 00:28:21,040 Speaker 2: You start with very early massive stars. Some of those collapse, 603 00:28:21,560 --> 00:28:24,600 Speaker 2: those remnants fall in together and form a dense core 604 00:28:24,640 --> 00:28:27,640 Speaker 2: at the heart of the galaxy, merging into the seeds 605 00:28:27,680 --> 00:28:30,640 Speaker 2: of black holes, which then slurp on more and more stuff. 606 00:28:30,880 --> 00:28:33,960 Speaker 2: But if you do those calculations, you run simulations, you 607 00:28:34,040 --> 00:28:37,800 Speaker 2: don't get super massive black holes, especially as early as 608 00:28:37,840 --> 00:28:40,240 Speaker 2: we see them in the universe. When we look back 609 00:28:40,280 --> 00:28:43,080 Speaker 2: in time and stuff really really far away, we see 610 00:28:43,120 --> 00:28:46,400 Speaker 2: super massive black holes with a massive a billion stars 611 00:28:46,880 --> 00:28:49,680 Speaker 2: in galaxies that form just a billion years after the 612 00:28:49,720 --> 00:28:53,040 Speaker 2: Big Bang. In our calculations, there just isn't enough time 613 00:28:53,080 --> 00:28:53,880 Speaker 2: for that to happen. 614 00:28:54,840 --> 00:28:58,720 Speaker 1: So then, what are some hypotheses about how these super 615 00:28:58,720 --> 00:28:59,720 Speaker 1: massive black holes form? 616 00:29:00,000 --> 00:29:02,640 Speaker 2: There are some crazy ideas, like one idea is that 617 00:29:02,760 --> 00:29:06,560 Speaker 2: maybe there are primordial black holes that you don't need 618 00:29:06,600 --> 00:29:09,760 Speaker 2: black holes to form from dead stars which then fall together. 619 00:29:10,120 --> 00:29:12,680 Speaker 2: But that during the Big Bang when matter was made, 620 00:29:13,120 --> 00:29:16,840 Speaker 2: also some black holes were made. Black holes not made 621 00:29:16,960 --> 00:29:20,120 Speaker 2: of protons and electrons and other kinds of matter. The 622 00:29:20,200 --> 00:29:23,280 Speaker 2: black holes that were made sort of before matter was matter. 623 00:29:23,440 --> 00:29:24,160 Speaker 1: What are they made out of? 624 00:29:24,280 --> 00:29:27,040 Speaker 2: They're made out of the pure energy in those quantum fields. 625 00:29:27,680 --> 00:29:30,360 Speaker 2: We think of protons and electrons, these particles as being 626 00:29:30,360 --> 00:29:32,920 Speaker 2: the basic building block of matter, But that's only true 627 00:29:32,960 --> 00:29:35,880 Speaker 2: when the universe is sort of cold and old. When 628 00:29:35,880 --> 00:29:38,840 Speaker 2: the universe is sort of younger and denser and hotter, 629 00:29:39,080 --> 00:29:41,520 Speaker 2: there's so much energy in these quantum fields it doesn't 630 00:29:41,560 --> 00:29:44,880 Speaker 2: really make sense to point at one little isolated blob 631 00:29:44,880 --> 00:29:48,160 Speaker 2: of that energy and call it a particle. It's so energetic, 632 00:29:48,160 --> 00:29:51,520 Speaker 2: it's all just sloshing around. And in that period there's 633 00:29:51,520 --> 00:29:54,800 Speaker 2: definitely enough energy to make black holes. What you need 634 00:29:54,880 --> 00:29:57,920 Speaker 2: is energy density, And so there are some theories that 635 00:29:57,960 --> 00:30:00,840 Speaker 2: in the very early universe, before things cool down enough 636 00:30:00,840 --> 00:30:03,520 Speaker 2: so you could talk about individual particles, some of that 637 00:30:03,640 --> 00:30:07,120 Speaker 2: energy was converted into primordial black holes, and if so, 638 00:30:07,360 --> 00:30:10,600 Speaker 2: they could be around to see the formation of these 639 00:30:10,720 --> 00:30:12,000 Speaker 2: super massive black holes. 640 00:30:12,200 --> 00:30:15,240 Speaker 1: Mmmm. Yeah, I definitely had more energy when I was 641 00:30:15,320 --> 00:30:20,959 Speaker 1: younger and hotter. Now I'm cold and old. So then 642 00:30:21,000 --> 00:30:23,720 Speaker 1: what's the scenario? Like you had these primorial black holes 643 00:30:23,960 --> 00:30:26,600 Speaker 1: very early in the universe, and then those just grew 644 00:30:27,000 --> 00:30:28,520 Speaker 1: a stuff fell into them. 645 00:30:28,680 --> 00:30:31,600 Speaker 2: Yeah, exactly. If you already had a black hole, it 646 00:30:31,680 --> 00:30:34,200 Speaker 2: could see the formation of a galaxy, and then you 647 00:30:34,200 --> 00:30:36,520 Speaker 2: wouldn't have to start from just the stars in that 648 00:30:36,560 --> 00:30:39,280 Speaker 2: galaxy to make your black hole. You're already starting from 649 00:30:39,360 --> 00:30:42,200 Speaker 2: half a billion solar masses or something, and then there 650 00:30:42,320 --> 00:30:45,280 Speaker 2: is time to make a billion, two billion, five billion 651 00:30:45,400 --> 00:30:47,920 Speaker 2: super massive black holes to the hearts of these galaxies 652 00:30:48,120 --> 00:30:49,240 Speaker 2: and like supercharges. 653 00:30:49,400 --> 00:30:53,280 Speaker 1: M I see. The mystery is not like how did 654 00:30:53,320 --> 00:30:55,719 Speaker 1: they get so big? It's more like how did they 655 00:30:55,760 --> 00:30:57,000 Speaker 1: get so big so fast? 656 00:30:57,040 --> 00:30:58,760 Speaker 2: Yeah? Exactly when they were so young? 657 00:30:58,800 --> 00:31:00,600 Speaker 1: Like there's enough stuff in each gall see to make 658 00:31:00,600 --> 00:31:02,800 Speaker 1: a super massive black hole given the times the univer 659 00:31:02,880 --> 00:31:05,080 Speaker 1: has been around, you can't figure out how they actually 660 00:31:05,440 --> 00:31:06,760 Speaker 1: got that big exactly. 661 00:31:06,840 --> 00:31:09,320 Speaker 2: Like if you see a seventeen year old with bulging muscles, 662 00:31:09,360 --> 00:31:11,280 Speaker 2: you're like, Okay, it must have worked out. If you 663 00:31:11,320 --> 00:31:14,360 Speaker 2: see like a seven month old with bulging muscles, You're like, 664 00:31:14,440 --> 00:31:16,320 Speaker 2: something is wrong here, what's going on? 665 00:31:17,880 --> 00:31:20,320 Speaker 1: Yeah? Does sound like a very wrong. 666 00:31:20,040 --> 00:31:22,720 Speaker 2: Picture pants or not. You don't want to see like 667 00:31:22,920 --> 00:31:25,080 Speaker 2: massive biceps on a seven month old. 668 00:31:24,920 --> 00:31:28,000 Speaker 1: All right, So that's one crazy idea. There's other crazy 669 00:31:28,000 --> 00:31:29,320 Speaker 1: ideas that maybe involve dark. 670 00:31:29,200 --> 00:31:31,920 Speaker 2: Matter, right, yeah, exactly. We know that dark matter plays 671 00:31:31,920 --> 00:31:34,560 Speaker 2: a big role in the formation of galaxies. So some 672 00:31:34,600 --> 00:31:37,479 Speaker 2: people wonder if you can make black holes out of 673 00:31:37,520 --> 00:31:40,440 Speaker 2: that dark matter. Because remember, dark matter is like eighty 674 00:31:40,520 --> 00:31:43,120 Speaker 2: percent of the matter in the universe. So if you 675 00:31:43,160 --> 00:31:45,000 Speaker 2: want to make stuff that's massive, like, you know, go 676 00:31:45,080 --> 00:31:48,760 Speaker 2: for your number one ingredient. The idea is that maybe 677 00:31:48,800 --> 00:31:51,880 Speaker 2: this dark matter can collapse into a black hole, again, 678 00:31:52,000 --> 00:31:55,160 Speaker 2: seeding the formation of these super massive black holes so 679 00:31:55,240 --> 00:31:57,360 Speaker 2: you don't just have to start from stars. 680 00:31:57,960 --> 00:32:00,200 Speaker 1: Does that mean that most black holes out there, or 681 00:32:00,480 --> 00:32:03,160 Speaker 1: most super massive black holes are made out of maybe 682 00:32:03,240 --> 00:32:04,400 Speaker 1: eighty percent dark matter. 683 00:32:04,600 --> 00:32:06,840 Speaker 2: It's a really good question and we don't know the answer. 684 00:32:07,200 --> 00:32:10,120 Speaker 2: We think that dark matter is less likely to collapse 685 00:32:10,160 --> 00:32:13,680 Speaker 2: into black holes than normal matter because it isn't sticky. 686 00:32:13,720 --> 00:32:17,120 Speaker 2: It's hard for it to lose its original rotational speed. 687 00:32:17,680 --> 00:32:20,440 Speaker 2: That's why the dark matter in galaxies tends to be 688 00:32:20,480 --> 00:32:23,600 Speaker 2: a bigger, puffier halo. You know, all the matter in 689 00:32:23,640 --> 00:32:26,520 Speaker 2: the galaxy used to be big and puffy and slowly rotating, 690 00:32:26,920 --> 00:32:30,920 Speaker 2: but then it gradually collapses into smaller, denser objects because 691 00:32:30,920 --> 00:32:33,400 Speaker 2: it bumps into itself or there's friction, and it slows 692 00:32:33,440 --> 00:32:36,760 Speaker 2: itself down and falls in towards the center. But dark 693 00:32:36,800 --> 00:32:39,240 Speaker 2: matter can't do that because it doesn't have those kind 694 00:32:39,240 --> 00:32:42,040 Speaker 2: of sticky interactions. It can't form big blobs, it can't 695 00:32:42,080 --> 00:32:45,720 Speaker 2: rub against itself, can't slow down, so it keeps swirling 696 00:32:46,040 --> 00:32:47,600 Speaker 2: in these big fluffy clouds. 697 00:32:47,720 --> 00:32:51,000 Speaker 1: Me mean like dark matter is even invisible to itself. 698 00:32:51,400 --> 00:32:55,520 Speaker 2: Yeah, it's not just invisible, it's intangible. It passes through itself, 699 00:32:55,560 --> 00:32:58,640 Speaker 2: we think. And so there must be some dark matter 700 00:32:58,720 --> 00:33:01,400 Speaker 2: in black holes, especially the ones at the center of galaxies, 701 00:33:01,440 --> 00:33:04,080 Speaker 2: because it's inevitable some dark matter particle will hit a 702 00:33:04,080 --> 00:33:06,880 Speaker 2: black hole event horizon. But we think that most of 703 00:33:06,880 --> 00:33:09,280 Speaker 2: the dark matter in the galaxy avoids falling into the 704 00:33:09,320 --> 00:33:12,760 Speaker 2: central black hole for that reason. But this theory suggests 705 00:33:12,760 --> 00:33:15,560 Speaker 2: that somehow some of it might have formed an over 706 00:33:15,640 --> 00:33:18,640 Speaker 2: density the heart of the galaxy and collapsed anyway. 707 00:33:18,400 --> 00:33:20,240 Speaker 1: To become a dark matter black hole. 708 00:33:20,120 --> 00:33:22,720 Speaker 2: To become a dark matter black hole, which then seeds 709 00:33:22,800 --> 00:33:24,600 Speaker 2: a super massive black hole. 710 00:33:24,680 --> 00:33:27,320 Speaker 1: All right, So most galaxies that we see around us 711 00:33:27,320 --> 00:33:30,840 Speaker 1: have a super massive black hole. How strong is that correlation? 712 00:33:31,000 --> 00:33:33,680 Speaker 2: So every single one except for those two exceptions, does 713 00:33:33,760 --> 00:33:36,440 Speaker 2: have a super massive black hole, And there's also an 714 00:33:36,480 --> 00:33:39,360 Speaker 2: interesting connection between the mass of that black hole and 715 00:33:39,440 --> 00:33:42,360 Speaker 2: what's going on in the rest of the galaxy. The 716 00:33:42,360 --> 00:33:45,480 Speaker 2: galaxy is this big flat disk usually and then this 717 00:33:45,640 --> 00:33:48,520 Speaker 2: the black hole of the center, but also this is bulge. 718 00:33:48,680 --> 00:33:51,680 Speaker 2: It's like blob of stars and gas and dust at 719 00:33:51,720 --> 00:33:53,520 Speaker 2: the center of the galaxy. 720 00:33:53,160 --> 00:33:54,880 Speaker 1: Sort of like the egg yulgan of fried Ek. 721 00:33:55,040 --> 00:33:58,400 Speaker 2: Yeah, exactly. And there tends to be a correlation between 722 00:33:58,440 --> 00:34:00,760 Speaker 2: the mass of the black hole and the mass of 723 00:34:00,760 --> 00:34:04,240 Speaker 2: that bulge like bigger bulge, bigger black hole, smaller bulge, 724 00:34:04,480 --> 00:34:07,840 Speaker 2: smaller black hole. And that feels like an important clue 725 00:34:07,880 --> 00:34:11,800 Speaker 2: because it tells us there's some connection, some correlation between 726 00:34:11,800 --> 00:34:14,759 Speaker 2: this really tiny but massive speck of the center of 727 00:34:14,800 --> 00:34:17,239 Speaker 2: the galaxy and what's going on in the rest of 728 00:34:17,280 --> 00:34:18,440 Speaker 2: the galaxy. 729 00:34:18,160 --> 00:34:20,839 Speaker 1: Meaning like if there's just a whole bunch more stuff there, 730 00:34:20,920 --> 00:34:23,200 Speaker 1: then maybe it's more likely that there is a black 731 00:34:23,200 --> 00:34:23,920 Speaker 1: hole at the center. 732 00:34:24,040 --> 00:34:26,319 Speaker 2: Yes, somehow there must be a process that affects both 733 00:34:26,360 --> 00:34:29,279 Speaker 2: of them. Either they're interacting in some way, or they're 734 00:34:29,320 --> 00:34:32,200 Speaker 2: both formed by the same process. The bulge in the 735 00:34:32,200 --> 00:34:34,800 Speaker 2: black hole definitely seem to be connected. It's not random. 736 00:34:35,080 --> 00:34:37,520 Speaker 2: It's not like you get huge bulges in tiny black holes, 737 00:34:37,600 --> 00:34:40,640 Speaker 2: or huge black holes and tiny bulges. So the bulge 738 00:34:40,680 --> 00:34:42,880 Speaker 2: is giving us some clue about the formation of the 739 00:34:42,880 --> 00:34:45,399 Speaker 2: black hole, because the process that made the black hole 740 00:34:45,440 --> 00:34:48,200 Speaker 2: has to also be involved somehow in the process of 741 00:34:48,239 --> 00:34:49,120 Speaker 2: making the bulge. 742 00:34:50,040 --> 00:34:53,239 Speaker 1: Now, how important is a super massive black hole to 743 00:34:53,400 --> 00:34:57,120 Speaker 1: the structure of that galaxy? Like if our galaxy suddenly 744 00:34:57,200 --> 00:34:59,439 Speaker 1: somebody plucked the super massive black hole in the middle 745 00:34:59,440 --> 00:35:03,080 Speaker 1: of our galaxy, where a galaxy look different or spiral 746 00:35:03,120 --> 00:35:05,520 Speaker 1: out of control or dissipate, or would it pretty much 747 00:35:05,640 --> 00:35:06,200 Speaker 1: be the same? 748 00:35:06,280 --> 00:35:07,960 Speaker 2: It would pretty much be the same. I mean, you 749 00:35:08,000 --> 00:35:11,040 Speaker 2: would disturb the orbits of stars in the very very center. 750 00:35:11,600 --> 00:35:15,279 Speaker 2: But even though super massive black holes sound awesome, their 751 00:35:15,320 --> 00:35:18,919 Speaker 2: mass is really tiny relative to the whole galaxy, much 752 00:35:18,960 --> 00:35:21,279 Speaker 2: much less than one percent, less than a tenth of 753 00:35:21,280 --> 00:35:23,839 Speaker 2: a one percent in many cases, and so it's really 754 00:35:23,840 --> 00:35:27,520 Speaker 2: an irrelevant part of the whole mass budget of the galaxy, 755 00:35:27,880 --> 00:35:30,480 Speaker 2: which is in the end what controls the dynamics and 756 00:35:30,480 --> 00:35:32,440 Speaker 2: the structure of the galaxy. 757 00:35:32,080 --> 00:35:34,240 Speaker 1: Like to have an impressent named super massive black holes. 758 00:35:34,360 --> 00:35:37,160 Speaker 1: But they really don't ender at the center of the galaxy. 759 00:35:37,200 --> 00:35:40,080 Speaker 1: But that's maybe just incidental. It's not like you need 760 00:35:40,120 --> 00:35:42,000 Speaker 1: a super massive black holes to have a galaxy. 761 00:35:42,080 --> 00:35:44,480 Speaker 2: Yeah, that's right, you don't. But it does seem like 762 00:35:44,520 --> 00:35:47,239 Speaker 2: they're connected to the center of the galaxy the rest 763 00:35:47,239 --> 00:35:49,319 Speaker 2: of it, you know, the ball just some process there 764 00:35:49,320 --> 00:35:52,200 Speaker 2: that either is connecting them. It's like a feedback mechanism, 765 00:35:52,239 --> 00:35:55,480 Speaker 2: so as one grows, the other one grows or against 766 00:35:55,480 --> 00:35:58,560 Speaker 2: some process that leads to both of them. So they 767 00:35:58,600 --> 00:36:00,640 Speaker 2: do seem to be connected to this to the galaxy. 768 00:36:00,640 --> 00:36:02,680 Speaker 2: But yeah, you could delete one or yet it out 769 00:36:02,719 --> 00:36:06,360 Speaker 2: into space without destroying the galaxy. The galaxy would spin on. 770 00:36:07,640 --> 00:36:11,160 Speaker 1: It's not like an essential ingredient in the formation of 771 00:36:11,200 --> 00:36:13,680 Speaker 1: a galaxy, No, not at all, but it does seem 772 00:36:13,680 --> 00:36:16,040 Speaker 1: to be maybe not necessary, but it does seem to 773 00:36:16,200 --> 00:36:18,879 Speaker 1: always be there because of most galaxies that we see Nero, 774 00:36:18,960 --> 00:36:20,879 Speaker 1: as you're saying, have a super massive black hole. 775 00:36:21,000 --> 00:36:24,080 Speaker 2: Yeah, so it seems like an important part of understanding 776 00:36:24,160 --> 00:36:27,640 Speaker 2: galaxy formation because they seem to almost always be created 777 00:36:28,080 --> 00:36:30,160 Speaker 2: and to be connected to the rest of the galaxy, 778 00:36:30,480 --> 00:36:33,120 Speaker 2: and they also might have clues about the expansion of 779 00:36:33,160 --> 00:36:35,719 Speaker 2: the universe. Remember, like a year ago, there was this 780 00:36:35,760 --> 00:36:39,040 Speaker 2: paper noticing a correlation between the masses of some of 781 00:36:39,040 --> 00:36:43,040 Speaker 2: these galaxies and the expansion of the universe, the theory 782 00:36:43,080 --> 00:36:45,400 Speaker 2: that these super massive black holes might actually be like 783 00:36:45,640 --> 00:36:49,040 Speaker 2: bubbles of dark energy, that they could be the things 784 00:36:49,120 --> 00:36:52,000 Speaker 2: expanding the universe and accelerating that expansion. 785 00:36:52,360 --> 00:36:55,839 Speaker 1: WHOA, all right, Well, as you said, there are two 786 00:36:55,920 --> 00:36:59,040 Speaker 1: galaxies that we know about that don't have super massive 787 00:36:59,040 --> 00:37:02,160 Speaker 1: black holes them, and so let's dig into why that is. 788 00:37:02,480 --> 00:37:05,200 Speaker 1: What happened to them? Did someone stealen did a physicist 789 00:37:05,680 --> 00:37:07,960 Speaker 1: lose them? So let's dig into that. But first let's 790 00:37:08,040 --> 00:37:22,839 Speaker 1: take another quick break. All right, we're asking the question 791 00:37:22,880 --> 00:37:26,680 Speaker 1: what happened to M thirty three's central black hole? And 792 00:37:26,760 --> 00:37:30,319 Speaker 1: this is a question because most galaxies seem to have 793 00:37:30,320 --> 00:37:32,440 Speaker 1: a super massive black hole in them, but not all 794 00:37:32,480 --> 00:37:34,480 Speaker 1: of them. So, Daniel, what happened to their pants? 795 00:37:36,520 --> 00:37:39,520 Speaker 2: Well, I think every galaxy except for the triangular galaxy 796 00:37:39,600 --> 00:37:42,640 Speaker 2: M thirty three, really can be connected to a super 797 00:37:42,680 --> 00:37:45,279 Speaker 2: massive black hole. Like almost all of them. There's a 798 00:37:45,320 --> 00:37:47,560 Speaker 2: super massive black hole and it's still in the center, 799 00:37:48,000 --> 00:37:51,280 Speaker 2: a tiny fraction of them no longer have a super 800 00:37:51,280 --> 00:37:54,000 Speaker 2: massive black hole. But in those situations you can usually 801 00:37:54,080 --> 00:37:57,000 Speaker 2: identify what happened. You can see the super massive black 802 00:37:57,000 --> 00:38:00,000 Speaker 2: hole having been tossed out into space in some crazy 803 00:38:00,640 --> 00:38:04,400 Speaker 2: three body interaction or a super massive black holes like 804 00:38:04,480 --> 00:38:06,840 Speaker 2: being kicked away from the center of the galaxy. So 805 00:38:06,880 --> 00:38:09,799 Speaker 2: it's still in the galaxy, but no longer at the core. 806 00:38:10,320 --> 00:38:13,480 Speaker 2: Except for M thirty three. M thirty three appears to 807 00:38:13,600 --> 00:38:16,400 Speaker 2: have no super massive black hole currently, and there's no 808 00:38:16,480 --> 00:38:18,839 Speaker 2: super massive black hole that you can associate with it 809 00:38:19,000 --> 00:38:19,440 Speaker 2: at all. 810 00:38:19,640 --> 00:38:21,759 Speaker 1: So it's just the galaxy out there. And so what 811 00:38:21,840 --> 00:38:23,600 Speaker 1: happens when you try to look in the middle, you 812 00:38:23,680 --> 00:38:26,880 Speaker 1: don't see any kind of like super quick turning in 813 00:38:26,920 --> 00:38:28,640 Speaker 1: the middle. Is that how you can tell that it 814 00:38:28,680 --> 00:38:30,120 Speaker 1: doesn't have a black hole in the middle? 815 00:38:30,280 --> 00:38:33,680 Speaker 2: Exactly? It's a lazy river. So this is a galaxy 816 00:38:33,760 --> 00:38:36,480 Speaker 2: that's two point seven light years away. It's in the 817 00:38:36,520 --> 00:38:40,560 Speaker 2: constellation Triangulum, so it's sometimes called M thirty three, sometimes 818 00:38:40,560 --> 00:38:44,000 Speaker 2: called the Triangulum galaxy, and it's a big galaxy. Like 819 00:38:44,040 --> 00:38:46,759 Speaker 2: in our local group, which is the cluster of galaxies 820 00:38:46,760 --> 00:38:49,960 Speaker 2: that we live in, there's Andromeda the biggest king galaxy. 821 00:38:50,160 --> 00:38:52,680 Speaker 2: There's the Milky Way, and then there's M thirty three, 822 00:38:53,000 --> 00:38:56,319 Speaker 2: so it's the third biggest galaxy sort of in the neighborhood. 823 00:38:56,800 --> 00:39:00,879 Speaker 2: It's got like sixty billion solar masses total. 824 00:39:00,680 --> 00:39:03,480 Speaker 1: Meaning it has sixty billion stars in them. 825 00:39:03,680 --> 00:39:05,799 Speaker 2: No, that's just a unit of mass. That's how you 826 00:39:05,880 --> 00:39:08,080 Speaker 2: measure the mass of something. It's like if somebody says 827 00:39:08,239 --> 00:39:10,719 Speaker 2: you're four stone, that does mean you're literally made of 828 00:39:10,760 --> 00:39:13,920 Speaker 2: four stones. Right. In this case, the galaxy is mostly 829 00:39:14,040 --> 00:39:17,280 Speaker 2: dark matter, So it definitely doesn't have sixty billion stars. 830 00:39:17,680 --> 00:39:20,280 Speaker 2: It's got a tiny fraction of that. It's mostly dark matter, 831 00:39:20,719 --> 00:39:22,920 Speaker 2: but it has enough stars that you can follow their 832 00:39:23,000 --> 00:39:25,520 Speaker 2: path at the core, you can measure the velocity and 833 00:39:25,560 --> 00:39:28,360 Speaker 2: from that you can infer the mass of any black 834 00:39:28,360 --> 00:39:29,840 Speaker 2: hole that could be at their center. 835 00:39:30,000 --> 00:39:32,160 Speaker 1: So this is kind of a small galaxy, right, because 836 00:39:32,200 --> 00:39:34,880 Speaker 1: our galaxy has a one hundred billion stars. 837 00:39:35,200 --> 00:39:37,640 Speaker 2: Yes, this is a smaller galaxy than the Milky Way, 838 00:39:37,680 --> 00:39:40,440 Speaker 2: but it's big compared to the neighborhood. I mean, our 839 00:39:40,480 --> 00:39:42,640 Speaker 2: galaxy is one of the bigger ones in the neighborhoods 840 00:39:42,719 --> 00:39:45,160 Speaker 2: is Andromeda, and then Milky Way. We're number two. So 841 00:39:45,239 --> 00:39:46,640 Speaker 2: this is number three. 842 00:39:46,320 --> 00:39:48,240 Speaker 1: And so you're saying, when we look in the middle, 843 00:39:48,239 --> 00:39:49,840 Speaker 1: we don't see a black hole at the center. 844 00:39:50,040 --> 00:39:52,760 Speaker 2: That's right. As you look at the stars, their orbits 845 00:39:52,800 --> 00:39:55,600 Speaker 2: don't get much faster as you get closer. If there's 846 00:39:55,640 --> 00:39:58,239 Speaker 2: a really big, super massive black hole there, then its 847 00:39:58,239 --> 00:40:00,720 Speaker 2: gravity is very powerful and for us start to stay 848 00:40:00,760 --> 00:40:02,959 Speaker 2: in orbit very close, it has to be going super 849 00:40:03,040 --> 00:40:06,240 Speaker 2: dup or fast. If there's no central black hole there, 850 00:40:06,360 --> 00:40:08,200 Speaker 2: then things can just be sort of like put putting 851 00:40:08,239 --> 00:40:11,480 Speaker 2: along near the center without being disturbed. It can survive 852 00:40:11,880 --> 00:40:13,160 Speaker 2: with slow velocities. 853 00:40:13,239 --> 00:40:15,280 Speaker 1: But I guess if this galaxy is that much smaller 854 00:40:15,320 --> 00:40:17,359 Speaker 1: than ours, could it be that it has a black 855 00:40:17,400 --> 00:40:19,280 Speaker 1: hole in the middle. It's just not at the super 856 00:40:19,320 --> 00:40:20,320 Speaker 1: massive level yet. 857 00:40:20,400 --> 00:40:22,600 Speaker 2: It could be that there is a black hole there. 858 00:40:23,040 --> 00:40:26,319 Speaker 2: But they can infer the maximum size a black hole 859 00:40:26,400 --> 00:40:29,680 Speaker 2: could be to be consistent with the motion of these stars, 860 00:40:30,200 --> 00:40:32,520 Speaker 2: and it would be a thousand times smaller than the 861 00:40:32,520 --> 00:40:35,560 Speaker 2: black hole you would expect for a galaxy this size. 862 00:40:35,760 --> 00:40:38,600 Speaker 2: So either there's no black hole there, or there's a 863 00:40:38,719 --> 00:40:41,840 Speaker 2: much smaller black hole than we expect to see for 864 00:40:41,880 --> 00:40:44,920 Speaker 2: a galaxy this size. If this one has a black hole, 865 00:40:45,040 --> 00:40:48,000 Speaker 2: then it has to be smaller than like fifteen hundred 866 00:40:48,239 --> 00:40:52,080 Speaker 2: solar masses. That's tiny. That's almost down to the stellar 867 00:40:52,160 --> 00:40:55,520 Speaker 2: mass black hole level. It's actually right in the intermediate 868 00:40:55,600 --> 00:40:58,000 Speaker 2: mass black hole region, which is quite interesting. 869 00:40:58,239 --> 00:41:01,399 Speaker 1: And so is there anything peculiar about the galaxies? Are 870 00:41:01,400 --> 00:41:03,759 Speaker 1: there any other clues about it that might tell you 871 00:41:03,800 --> 00:41:05,000 Speaker 1: why it doesn't have a black hole? 872 00:41:05,200 --> 00:41:08,000 Speaker 2: One other clue is that it doesn't really have a bulge. 873 00:41:08,200 --> 00:41:11,200 Speaker 2: We were talking earlier about how most galaxies that have 874 00:41:11,280 --> 00:41:15,080 Speaker 2: really big massive black holes also have really big bulges. Well, 875 00:41:15,120 --> 00:41:18,000 Speaker 2: this one's got no black hole or maybe a tiny one, 876 00:41:18,040 --> 00:41:22,120 Speaker 2: and almost no bulge. So it really suggests that black 877 00:41:22,160 --> 00:41:25,920 Speaker 2: holes are closely associated with the bulge. Whatever makes the 878 00:41:25,960 --> 00:41:28,360 Speaker 2: disc is not connected to the black hole, but whatever 879 00:41:28,440 --> 00:41:31,720 Speaker 2: is making the bulge is deeply connected to the formation 880 00:41:31,840 --> 00:41:33,960 Speaker 2: of that super massive black hole. So it feels like 881 00:41:34,000 --> 00:41:34,520 Speaker 2: a clue. 882 00:41:35,520 --> 00:41:37,520 Speaker 1: Maybe this galaxy just works out a lot. You know, 883 00:41:37,719 --> 00:41:39,360 Speaker 1: it doesn't have a bulge. 884 00:41:39,920 --> 00:41:42,240 Speaker 2: Wouldn't that give it a bulge bulging muscles? 885 00:41:42,560 --> 00:41:44,960 Speaker 1: Well, it depends on your workout, I guess true. Like 886 00:41:45,000 --> 00:41:48,319 Speaker 1: if you just run a lot, you just a slim and. 887 00:41:48,360 --> 00:41:51,000 Speaker 2: Trim This is a spelt galaxy. 888 00:41:51,040 --> 00:41:53,920 Speaker 1: You're saying Yeah, there you go like a runnery galaxy. Yeah, 889 00:41:54,000 --> 00:41:56,799 Speaker 1: are there other galaxies that we've seen out there that 890 00:41:56,920 --> 00:42:00,200 Speaker 1: are this size don't have a bulge? But do you 891 00:42:00,239 --> 00:42:03,160 Speaker 1: have a black hole? Or is there a relationship between 892 00:42:03,280 --> 00:42:04,520 Speaker 1: bulges and black holes? 893 00:42:04,560 --> 00:42:07,839 Speaker 2: This is close relationship between bulges and black holes. Other 894 00:42:07,920 --> 00:42:11,800 Speaker 2: galaxies roughly the size have bulges and have black holes. 895 00:42:12,320 --> 00:42:14,040 Speaker 2: This is the only one we've seen without a black 896 00:42:14,040 --> 00:42:16,600 Speaker 2: hole and also without a significant bulge. 897 00:42:16,840 --> 00:42:19,200 Speaker 1: Is it the only one we've seen without a bulge? Yeah, Like, 898 00:42:19,239 --> 00:42:22,160 Speaker 1: out of the Brazilian galaxies out there, we've only seen 899 00:42:22,239 --> 00:42:23,280 Speaker 1: one without a bulge. 900 00:42:23,360 --> 00:42:26,560 Speaker 2: We see smaller ones with smaller bulges and smaller black holes, 901 00:42:26,560 --> 00:42:28,440 Speaker 2: but this is the edge of the spectrum. This is 902 00:42:28,480 --> 00:42:31,080 Speaker 2: the tiniest bulge and tiniest black hole. 903 00:42:31,440 --> 00:42:35,280 Speaker 1: Oh interesting, So it's truly unique in the entire universe, 904 00:42:35,400 --> 00:42:37,480 Speaker 1: or we just haven't seen enough galaxies. 905 00:42:37,480 --> 00:42:40,720 Speaker 2: We've definitely not seen enough galaxies. We've looked at thousands 906 00:42:40,719 --> 00:42:43,920 Speaker 2: of galaxies and measured the massive black holes of hundreds 907 00:42:43,920 --> 00:42:46,200 Speaker 2: of them. So this is early days, you know. This 908 00:42:46,280 --> 00:42:49,120 Speaker 2: is the kind of science where you're discovering individual ones 909 00:42:49,160 --> 00:42:52,000 Speaker 2: and wondering if they're typical or weird. You know. It's 910 00:42:52,040 --> 00:42:54,880 Speaker 2: like when we were first discovering exoplanets and we didn't know, 911 00:42:55,080 --> 00:42:57,879 Speaker 2: is every planet out there hot Jupiter? Oh, it turns 912 00:42:57,920 --> 00:42:59,719 Speaker 2: out that's just the first ones we see, because that's 913 00:42:59,719 --> 00:43:02,120 Speaker 2: what we're good at. And so we haven't seen a 914 00:43:02,200 --> 00:43:04,919 Speaker 2: whole lot of examples of super massive black holes because 915 00:43:04,920 --> 00:43:07,600 Speaker 2: it's tricky, right, you have to measure the velocities of 916 00:43:07,680 --> 00:43:10,719 Speaker 2: stars near the centers of other galaxies. In order to 917 00:43:10,760 --> 00:43:13,399 Speaker 2: do this kind of measurement, it's hard, so we don't 918 00:43:13,400 --> 00:43:15,360 Speaker 2: have a lot of data, so there's always going to 919 00:43:15,400 --> 00:43:16,960 Speaker 2: be an outlier when you have a small sample. 920 00:43:17,440 --> 00:43:20,040 Speaker 1: We've seen like maybe billions of galaxies out there. Are 921 00:43:20,040 --> 00:43:22,239 Speaker 1: you saying we've only studied a few hundred of them. 922 00:43:22,280 --> 00:43:24,719 Speaker 2: We've seen zillions and zillions of galaxies. You're right, and 923 00:43:24,800 --> 00:43:27,480 Speaker 2: James Webb's excellent and the Hubble Deep Field shows us 924 00:43:27,480 --> 00:43:30,400 Speaker 2: lots and lots of galaxies, But in terms of measuring 925 00:43:30,440 --> 00:43:33,120 Speaker 2: the super massive black hole, most of those we can't. 926 00:43:33,480 --> 00:43:34,680 Speaker 2: The only way they do it is for them to 927 00:43:34,719 --> 00:43:36,920 Speaker 2: be close enough for us to be able to measure 928 00:43:36,960 --> 00:43:40,800 Speaker 2: the stellar velocities near the heart of the galaxy, or 929 00:43:41,040 --> 00:43:44,040 Speaker 2: to see the quasar from a really, really old galaxy 930 00:43:44,160 --> 00:43:46,160 Speaker 2: and that adds up to a few hundred mmm. 931 00:43:47,480 --> 00:43:49,800 Speaker 1: So then that's the kind of central mystery of today, 932 00:43:50,080 --> 00:43:52,120 Speaker 1: which is that you have this galaxy. I'm thirty three 933 00:43:52,239 --> 00:43:55,120 Speaker 1: triangulum and it looks like it's a small galaxy, but 934 00:43:55,239 --> 00:43:57,799 Speaker 1: it's a pretty regular galaxy and it doesn't have a 935 00:43:57,840 --> 00:44:00,400 Speaker 1: super massive black hole in it. Yeah, exactly we have 936 00:44:00,520 --> 00:44:01,959 Speaker 1: is that it doesn't have a bulge. 937 00:44:01,640 --> 00:44:05,239 Speaker 2: Exactly, and so it's like never worn pants, you know, 938 00:44:05,280 --> 00:44:08,520 Speaker 2: it's like happy in its pants. Free existence. Doesn't seem 939 00:44:08,560 --> 00:44:11,000 Speaker 2: like it had a super massive black hole and lost it, 940 00:44:11,080 --> 00:44:13,800 Speaker 2: because then it would have a bulge with no black hole. 941 00:44:14,239 --> 00:44:16,520 Speaker 2: And we don't understand how these things form at all, 942 00:44:16,560 --> 00:44:18,799 Speaker 2: and so there's this interesting clue, but the connection with 943 00:44:18,880 --> 00:44:20,600 Speaker 2: the bulge and not with the rest of the disk. 944 00:44:21,480 --> 00:44:23,319 Speaker 2: So as we see more and more of these things, 945 00:44:23,320 --> 00:44:25,640 Speaker 2: we hope to learn more about how galaxies form and 946 00:44:25,680 --> 00:44:29,480 Speaker 2: how super massive black holes form. But these exceptions, these outliers, 947 00:44:29,520 --> 00:44:32,120 Speaker 2: are really important clues because they tell us what rules 948 00:44:32,120 --> 00:44:33,359 Speaker 2: can be broken, right. 949 00:44:33,480 --> 00:44:36,240 Speaker 1: It sort of tells you like what's necessary and what isn't, 950 00:44:36,680 --> 00:44:38,879 Speaker 1: Like you can't have a galaxy without a bulky. 951 00:44:39,160 --> 00:44:41,120 Speaker 2: You can have a galaxy without a bulge and without 952 00:44:41,120 --> 00:44:42,920 Speaker 2: a black hole at its heart, you still get a 953 00:44:43,000 --> 00:44:44,080 Speaker 2: very nice galaxy. 954 00:44:44,120 --> 00:44:46,960 Speaker 1: And you can get a galaxy without pants, and it 955 00:44:47,000 --> 00:44:48,000 Speaker 1: seems perfectly happy. 956 00:44:48,120 --> 00:44:50,840 Speaker 2: I don't recommend doing that, but yeah, it does seem possible. 957 00:44:52,920 --> 00:44:54,520 Speaker 1: Dan, What happened to your pants right now? 958 00:44:55,320 --> 00:44:55,920 Speaker 2: No comment? 959 00:44:56,800 --> 00:44:58,000 Speaker 1: Exactly, it's a mystery. 960 00:44:58,760 --> 00:44:59,879 Speaker 2: I lost them in the black hole. 961 00:45:00,040 --> 00:45:01,960 Speaker 1: I went to your black hole that you lost, and 962 00:45:02,000 --> 00:45:04,120 Speaker 1: so that's why you're looking for your black hole because 963 00:45:04,160 --> 00:45:05,640 Speaker 1: it it's running away with your pants. 964 00:45:05,760 --> 00:45:07,600 Speaker 2: But without pants on, it can't go outside and look 965 00:45:07,640 --> 00:45:08,560 Speaker 2: for it. So now I'm stuck. 966 00:45:08,880 --> 00:45:10,560 Speaker 1: Oh man, you're gonna have to ask your friends on 967 00:45:10,560 --> 00:45:14,919 Speaker 1: Twitter to look for your pants and your black hole. 968 00:45:14,960 --> 00:45:17,160 Speaker 2: Go fund me for new pants for Daniel. There you go. 969 00:45:17,560 --> 00:45:21,759 Speaker 1: That's what the Internet wasn't there for pants free Fridays? 970 00:45:22,280 --> 00:45:25,719 Speaker 1: All right? Well, another interesting example of how there is 971 00:45:25,920 --> 00:45:28,319 Speaker 1: still so much mystery in the universe. Even I feel 972 00:45:28,360 --> 00:45:30,280 Speaker 1: like this is a mystery wrapped inside of a mystery, 973 00:45:30,280 --> 00:45:32,520 Speaker 1: because black holes are a mystery. But this is about 974 00:45:32,520 --> 00:45:35,239 Speaker 1: the missing black hole, so it's like the mystery or 975 00:45:35,239 --> 00:45:35,960 Speaker 1: the missing mystery? 976 00:45:36,120 --> 00:45:39,359 Speaker 2: Yeah, exactly where did the mystery go? All right? 977 00:45:39,440 --> 00:45:42,239 Speaker 1: Well, we hope you enjoyed that. Thanks for joining us, 978 00:45:43,280 --> 00:45:44,040 Speaker 1: See you next time. 979 00:45:48,719 --> 00:45:51,879 Speaker 2: For more science and curiosity, come find us on social media, 980 00:45:52,000 --> 00:45:56,560 Speaker 2: where we answer questions and post videos. We're on Twitter, Discord, Instant, 981 00:45:56,640 --> 00:46:00,360 Speaker 2: and now TikTok. Thanks for listening and remember that Daniel 982 00:46:00,400 --> 00:46:03,840 Speaker 2: and Jorge Explain the Universe is a production of iHeartRadio. 983 00:46:04,120 --> 00:46:09,239 Speaker 2: For more podcasts from iHeartRadio, visit the iHeartRadio app, Apple Podcasts, 984 00:46:09,400 --> 00:46:11,760 Speaker 2: or wherever you listen to your favorite shows.