1 00:00:08,520 --> 00:00:12,280 Speaker 1: Hey, Jorgey, I have a pop quiz for you. Was 2 00:00:12,320 --> 00:00:16,280 Speaker 1: this in the syllabus? Did you read the syllabus? And 3 00:00:16,280 --> 00:00:19,520 Speaker 1: then another was one? Then yes, it was on the syllabus. 4 00:00:19,880 --> 00:00:22,040 Speaker 1: All right, that sounds fair. All right, hit me up. 5 00:00:22,200 --> 00:00:27,800 Speaker 1: What is the object that astronomers call a blondet? Interesting? 6 00:00:28,360 --> 00:00:31,479 Speaker 1: It sounds like a block internet, maybe like the less 7 00:00:31,520 --> 00:00:36,720 Speaker 1: exciting version of the Internet. Close. All right, well it's 8 00:00:36,760 --> 00:00:39,879 Speaker 1: it's it's astronomy. So I'm guessing maybe it sounds like planet, 9 00:00:40,159 --> 00:00:43,800 Speaker 1: but maybe it's like a black planet or or i know, 10 00:00:44,000 --> 00:00:47,400 Speaker 1: like a black hole planet ding ding ding. You it's 11 00:00:47,440 --> 00:00:51,720 Speaker 1: a planet that orbits a black hole. Oh? Interesting? So 12 00:00:51,840 --> 00:00:55,040 Speaker 1: sometimes astronomy does come up with sort of names that 13 00:00:55,080 --> 00:00:58,920 Speaker 1: makes sense. Sometimes it's being generous. Just be glad I 14 00:00:58,960 --> 00:01:01,680 Speaker 1: didn't ask you what a plun it is. I'm glad 15 00:01:01,680 --> 00:01:03,880 Speaker 1: you didn't ask me that what what a plunent is? Weight? 16 00:01:04,200 --> 00:01:07,120 Speaker 1: Is a pluted a real thing? Absolutely? Is it a 17 00:01:07,120 --> 00:01:25,279 Speaker 1: more pluish version of the Internet. Hi am or Handmae 18 00:01:25,319 --> 00:01:28,240 Speaker 1: cartoonists and the creator of PhD commics. Hi, I'm Daniel. 19 00:01:28,280 --> 00:01:31,200 Speaker 1: I am a particle physicist and a professor UC Irvine, 20 00:01:31,319 --> 00:01:34,759 Speaker 1: and I would never joke about plunets. Does that make 21 00:01:34,760 --> 00:01:40,720 Speaker 1: you a plute? Pessor I always try to tell the plute, well, 22 00:01:40,720 --> 00:01:44,559 Speaker 1: that's a real plus. But plunets are a real thing. Really, 23 00:01:44,600 --> 00:01:47,360 Speaker 1: what are they? What's a plutt? A plunt is a 24 00:01:47,400 --> 00:01:50,800 Speaker 1: moon turned planet. It used to be a moon orbiting 25 00:01:50,800 --> 00:01:53,240 Speaker 1: a planet, but then it was set free and is 26 00:01:53,280 --> 00:01:57,840 Speaker 1: now wandering the Solar System and counts as a planet. Oh. Interesting, 27 00:01:58,120 --> 00:02:01,360 Speaker 1: so you started the word moon inside of the planet. 28 00:02:01,680 --> 00:02:05,080 Speaker 1: Interesting You didn't like combine it or you like literally 29 00:02:05,160 --> 00:02:08,440 Speaker 1: merged it. Yeah, exactly. You know, take the old job 30 00:02:08,480 --> 00:02:10,680 Speaker 1: and in certain inside the new jobs. So for example, 31 00:02:11,000 --> 00:02:17,359 Speaker 1: you know your job would be car engineer, tunist engineers. 32 00:02:17,639 --> 00:02:21,560 Speaker 1: I like that a little bit better engineer engineers. There 33 00:02:21,560 --> 00:02:25,480 Speaker 1: you go, anything that involves ingenuity, and you're no longer 34 00:02:25,639 --> 00:02:28,560 Speaker 1: orbiting anything but Welcome to our podcast Daniel and Jorge 35 00:02:28,560 --> 00:02:31,360 Speaker 1: Explain the Universe, a production of I Heart Radio in 36 00:02:31,400 --> 00:02:34,080 Speaker 1: which we mash up all of the crazy ideas that 37 00:02:34,120 --> 00:02:36,920 Speaker 1: are out there in the universe. The planets, the moons, 38 00:02:36,960 --> 00:02:39,959 Speaker 1: the pluets, the blondet's, the black holes, the new drown stars, 39 00:02:40,000 --> 00:02:43,840 Speaker 1: the quasars, the tiny little particles, and even the hypothetical 40 00:02:43,880 --> 00:02:47,480 Speaker 1: stuff that might not exist all in a desperate attempt 41 00:02:47,560 --> 00:02:51,160 Speaker 1: to understand this glorious and incredible universe that we find 42 00:02:51,240 --> 00:02:55,200 Speaker 1: ourselves in that provides us with so many satisfying, deep, rich, 43 00:02:55,320 --> 00:02:59,440 Speaker 1: and cosmically contextual questions about the nature and meaning of 44 00:02:59,520 --> 00:03:04,080 Speaker 1: our lives. Cosmically contextual questions. That's a great alliteration there, 45 00:03:04,480 --> 00:03:09,760 Speaker 1: it's positivitivitally fluish. I am inspiring a literationist, but it 46 00:03:09,840 --> 00:03:12,560 Speaker 1: is at an incredible and wonderful universe out there, full 47 00:03:12,600 --> 00:03:15,160 Speaker 1: of interesting things that we've named, that we haven't named, 48 00:03:15,520 --> 00:03:18,200 Speaker 1: things that we understand, and things that we don't understand 49 00:03:18,360 --> 00:03:20,840 Speaker 1: and we have yet to understand and that will hopefully 50 00:03:20,960 --> 00:03:23,320 Speaker 1: learn more about in the future. That's right, it's a 51 00:03:23,400 --> 00:03:26,680 Speaker 1: never ending journey to answer the questions about the universe. 52 00:03:27,000 --> 00:03:29,960 Speaker 1: Or he asked me earlier, if somebody is wants a physicist, 53 00:03:30,000 --> 00:03:32,680 Speaker 1: if they're always a physicist, and I think that the 54 00:03:32,720 --> 00:03:35,720 Speaker 1: answer is that everybody out there is a physicist because 55 00:03:35,760 --> 00:03:39,040 Speaker 1: we all want to know answers to the deepest questions 56 00:03:39,120 --> 00:03:41,680 Speaker 1: about the universe. Yeah, we all have questions, we all 57 00:03:41,720 --> 00:03:44,400 Speaker 1: wonder about the world around us. And I guess that 58 00:03:44,440 --> 00:03:47,160 Speaker 1: makes you a physicist, right, I mean technically, anyone who 59 00:03:47,160 --> 00:03:49,400 Speaker 1: wonders about the universe and how it works is sort 60 00:03:49,440 --> 00:03:52,240 Speaker 1: of a scientist, right. Yeah, physics is just trying to 61 00:03:52,280 --> 00:03:55,920 Speaker 1: tell mathematical stories to answer our questions about the universe, 62 00:03:56,320 --> 00:03:58,360 Speaker 1: and we all have those questions and trying to build 63 00:03:58,360 --> 00:04:02,200 Speaker 1: in our heads models about how the universe works. Professional 64 00:04:02,200 --> 00:04:04,040 Speaker 1: physicists who do it for their day job take it 65 00:04:04,080 --> 00:04:07,000 Speaker 1: one step further and devote their lives to it. But 66 00:04:07,080 --> 00:04:10,840 Speaker 1: I think it's something that everybody and some level is doing. Interesting. 67 00:04:10,840 --> 00:04:12,520 Speaker 1: Does that mean you go around saying, Hi, I'm a 68 00:04:12,600 --> 00:04:18,960 Speaker 1: pro physicist. Stand back, I'm a professional. That's right. Like 69 00:04:19,080 --> 00:04:23,479 Speaker 1: professional wrestlers. You need to take professional physicists much more seriously. Yeah, 70 00:04:23,520 --> 00:04:25,679 Speaker 1: I'm sure you get paid as much as professional athletes 71 00:04:25,720 --> 00:04:28,480 Speaker 1: as well. You should see me in costume. Yeah, and 72 00:04:28,920 --> 00:04:31,000 Speaker 1: I'm sure there's an n p A also a National 73 00:04:31,279 --> 00:04:35,039 Speaker 1: Physics Association, Right. You have a world championship too, Oh yeah, 74 00:04:35,040 --> 00:04:38,839 Speaker 1: we call it a SmackDown. Also, you technically kind of 75 00:04:38,839 --> 00:04:41,120 Speaker 1: have teams, right like you and the people in your department. 76 00:04:41,160 --> 00:04:42,880 Speaker 1: You're sort of a team, and you're sort of competing 77 00:04:42,880 --> 00:04:45,560 Speaker 1: against other teams in a way, right to uncover the 78 00:04:45,560 --> 00:04:47,719 Speaker 1: secrets of the universe. That's true. We do have a 79 00:04:47,760 --> 00:04:50,320 Speaker 1: group here at Irvine that all sort of works together 80 00:04:50,560 --> 00:04:54,400 Speaker 1: probing the universe in different ways, plasma physics, condensed matter physics, 81 00:04:54,480 --> 00:04:57,359 Speaker 1: all the way to astronomy um also a member of 82 00:04:57,400 --> 00:04:59,920 Speaker 1: other teams like I'm a member of the Atlas Collaboration, 83 00:05:00,120 --> 00:05:02,800 Speaker 1: which is a group of thousands of scientists all working 84 00:05:02,839 --> 00:05:05,799 Speaker 1: together to try to understand the basic constituents of matter. 85 00:05:06,160 --> 00:05:09,840 Speaker 1: And we have competition. The CMS Collaboration is like five 86 00:05:09,839 --> 00:05:13,320 Speaker 1: thousand other scientists trying to beat us to the punch. Interesting. 87 00:05:13,320 --> 00:05:15,040 Speaker 1: How many teams are you a part of that? Do? It? 88 00:05:15,040 --> 00:05:18,880 Speaker 1: Sounds like you're very promising businesses. I'm a prolific collaborator, 89 00:05:18,960 --> 00:05:22,599 Speaker 1: that's true. Yes, you're a professional, prolific promisk business That 90 00:05:22,600 --> 00:05:26,560 Speaker 1: sounds very positive. Well, I'm pro you anyways. But yeah, 91 00:05:26,600 --> 00:05:29,440 Speaker 1: it's an interesting universe full of mysterious things, and nothing 92 00:05:29,600 --> 00:05:33,520 Speaker 1: is more mysterious, it seems, than an interesting object that 93 00:05:33,680 --> 00:05:35,960 Speaker 1: we thought was theoretical for a long time, but that 94 00:05:36,040 --> 00:05:38,800 Speaker 1: we now have pictures of out there in the cosmos. 95 00:05:39,080 --> 00:05:42,159 Speaker 1: Maybe the most challenging thing to wrap our minds around 96 00:05:42,200 --> 00:05:44,960 Speaker 1: to understand that it might really be out there in 97 00:05:45,040 --> 00:05:49,120 Speaker 1: our universe. Not just a product of mathematical calculations, but 98 00:05:49,200 --> 00:05:53,479 Speaker 1: a reality, something one could actually fall into and experience, 99 00:05:53,760 --> 00:05:56,400 Speaker 1: something one could actually see with their own eyes. Are 100 00:05:56,440 --> 00:06:00,599 Speaker 1: these weird mysterious corners of space black holes? Were gravity 101 00:06:00,640 --> 00:06:04,000 Speaker 1: and space time are so intense that nothing, not even 102 00:06:04,120 --> 00:06:06,640 Speaker 1: light can escape. Yeah, and they are frustrating to think 103 00:06:06,640 --> 00:06:08,600 Speaker 1: about and to wonder about because they are They are 104 00:06:08,640 --> 00:06:10,960 Speaker 1: literally sort of hidden from the universe. They are not 105 00:06:11,040 --> 00:06:14,120 Speaker 1: just black holes and names. They are actual sort of 106 00:06:14,160 --> 00:06:17,719 Speaker 1: holes in the fabric of spacetime and reality itself. Yeah, 107 00:06:17,720 --> 00:06:21,320 Speaker 1: they're almost like a separate universe. They are detached from 108 00:06:21,320 --> 00:06:23,800 Speaker 1: our universe. Once you fall into a black hole, it's 109 00:06:23,800 --> 00:06:26,400 Speaker 1: not that you can't escape because you can't go fast 110 00:06:26,520 --> 00:06:28,760 Speaker 1: enough because the limit of the speed of light. It's 111 00:06:28,800 --> 00:06:32,360 Speaker 1: because the shape of space is so crazy, so distorted, 112 00:06:32,400 --> 00:06:35,880 Speaker 1: so curved, that they are one directional, that every path 113 00:06:36,000 --> 00:06:39,120 Speaker 1: leads you towards the center. So in some sense, everything 114 00:06:39,160 --> 00:06:42,480 Speaker 1: inside the event horizon is like its own little universe. 115 00:06:42,520 --> 00:06:46,080 Speaker 1: It's detached from normal space time. Yeah, whatever happens in 116 00:06:46,080 --> 00:06:48,200 Speaker 1: a black hole stays in a black hole. You can 117 00:06:48,240 --> 00:06:51,039 Speaker 1: do whatever you want. You can relive your wild days 118 00:06:51,040 --> 00:06:53,200 Speaker 1: inside of a black hole. That's right, the original Las 119 00:06:53,320 --> 00:06:56,599 Speaker 1: Vegas and did that Vegas instead of a black hole? 120 00:06:56,640 --> 00:06:59,679 Speaker 1: If you think about it, at least for people's money 121 00:06:59,760 --> 00:07:02,360 Speaker 1: and prudence, that's right, it leaves a black hole in 122 00:07:02,400 --> 00:07:05,000 Speaker 1: their hearts. Yeah, black holes are super mysterious and they 123 00:07:05,040 --> 00:07:07,440 Speaker 1: seem to sort of occupy a big hole and and 124 00:07:07,520 --> 00:07:10,520 Speaker 1: people's curiosity. It's one of the things we get asked 125 00:07:10,520 --> 00:07:13,880 Speaker 1: about the most on our social media and through email. 126 00:07:13,960 --> 00:07:16,000 Speaker 1: That's right. And it's not just you folks out there 127 00:07:16,000 --> 00:07:18,960 Speaker 1: who are super curious about black holes and what's inside 128 00:07:18,960 --> 00:07:23,400 Speaker 1: of them. Professional physicist experts in relativity and quantum mechanics 129 00:07:23,560 --> 00:07:27,040 Speaker 1: are also desperately curious to know what's inside a black 130 00:07:27,080 --> 00:07:30,480 Speaker 1: hole because, at their hearts, they might contain the answer 131 00:07:30,520 --> 00:07:34,320 Speaker 1: to one of the biggest open questions in physics, which 132 00:07:34,360 --> 00:07:38,200 Speaker 1: is how gravity and quantum mechanics work together, or if 133 00:07:38,280 --> 00:07:42,240 Speaker 1: they do. Gravity and quantum mechanics are our two pillars 134 00:07:42,240 --> 00:07:45,120 Speaker 1: of understanding the universe, but they have very very different 135 00:07:45,120 --> 00:07:47,960 Speaker 1: pictures about how the universe works. But most of the 136 00:07:48,000 --> 00:07:50,120 Speaker 1: time we only need to use one of them, gravity 137 00:07:50,360 --> 00:07:53,880 Speaker 1: or quantum mechanics. It's inside a black hole that both 138 00:07:53,880 --> 00:07:56,800 Speaker 1: of them are needed. But unfortunately we don't really know 139 00:07:57,000 --> 00:07:59,880 Speaker 1: what they are doing together inside the black hole, because 140 00:07:59,880 --> 00:08:02,840 Speaker 1: of course it's hidden from us. Yeah, those secrets are 141 00:08:02,960 --> 00:08:05,440 Speaker 1: locked inside a black holes and we may never get 142 00:08:05,480 --> 00:08:08,920 Speaker 1: to him because nothing, not even light, escapes a black hole. 143 00:08:09,240 --> 00:08:13,320 Speaker 1: And yet, somehow ironically or interestingly, black holes are some 144 00:08:13,480 --> 00:08:16,440 Speaker 1: of the brightest things in the universe. Black holes are 145 00:08:16,480 --> 00:08:19,440 Speaker 1: not completely dark, that's right, And we hope that by 146 00:08:19,520 --> 00:08:22,680 Speaker 1: studying what happens outside a black hole, in the neighborhood 147 00:08:22,680 --> 00:08:24,840 Speaker 1: of a black hole, the things the black hole does 148 00:08:24,920 --> 00:08:27,680 Speaker 1: to the space and objects around it, perhaps we can 149 00:08:27,720 --> 00:08:30,640 Speaker 1: start to get a glimmer of what's going on inside. 150 00:08:30,840 --> 00:08:32,480 Speaker 1: So to be on the program, we'll be asking the 151 00:08:32,559 --> 00:08:42,720 Speaker 1: question what makes black holes glow interesting? You mean like 152 00:08:42,800 --> 00:08:45,280 Speaker 1: glow from light or just they just have a positive 153 00:08:45,320 --> 00:08:48,680 Speaker 1: disposition about their career. Arc is just incredible. They just 154 00:08:48,720 --> 00:08:53,720 Speaker 1: get bigger and bigger and bigger second and more attention 155 00:08:53,720 --> 00:08:55,880 Speaker 1: as they go along. That's right. They go from de 156 00:08:56,040 --> 00:08:58,320 Speaker 1: list to C list, the list and then finally a 157 00:08:58,440 --> 00:09:01,400 Speaker 1: list as in astronomical st ours. Yeah, not be less 158 00:09:01,480 --> 00:09:04,240 Speaker 1: like black hole. But yeah, black holes are super interesting 159 00:09:04,280 --> 00:09:08,000 Speaker 1: because they are mysterious and they trapped even light itself. 160 00:09:08,040 --> 00:09:10,920 Speaker 1: But also they glow, right, They sort of glow out 161 00:09:10,920 --> 00:09:12,560 Speaker 1: there in the universe. Sometimes they are even some of 162 00:09:12,600 --> 00:09:14,920 Speaker 1: the brightest things in the night's time. Yea. And we 163 00:09:14,960 --> 00:09:17,600 Speaker 1: have been looking at black holes for almost a hundred 164 00:09:17,640 --> 00:09:20,000 Speaker 1: years without knowing it. Some of the things that we've 165 00:09:20,040 --> 00:09:22,720 Speaker 1: been studying for decades and decades and decades we only 166 00:09:22,760 --> 00:09:26,640 Speaker 1: recently discovered are actually black holes. Yeah, so they're not 167 00:09:26,720 --> 00:09:28,920 Speaker 1: just sort of sitting out there in space sucking stuff 168 00:09:28,960 --> 00:09:31,360 Speaker 1: up and looking dark and mysterious. They also sort of 169 00:09:31,480 --> 00:09:33,559 Speaker 1: shine brightly, and at least some of them give off 170 00:09:33,600 --> 00:09:36,920 Speaker 1: a crazy amount of radiation. That's how we sort of 171 00:09:37,040 --> 00:09:39,080 Speaker 1: know where they are. So, as usually, we were wondering 172 00:09:39,080 --> 00:09:41,400 Speaker 1: how many people out there had thought about the glow 173 00:09:41,480 --> 00:09:43,880 Speaker 1: of black holes, or whether they even knew black holes 174 00:09:43,920 --> 00:09:47,240 Speaker 1: glowed brightly. So Daniel went out there into the internet 175 00:09:47,280 --> 00:09:50,200 Speaker 1: to ask people why the black holes glow so brightly. 176 00:09:50,320 --> 00:09:53,200 Speaker 1: And we are very interested in hearing you speculate without 177 00:09:53,200 --> 00:09:56,920 Speaker 1: preparation on topics for future episodes. So if you'd like 178 00:09:57,040 --> 00:10:00,719 Speaker 1: to participate, please send us your name to questions at 179 00:10:00,800 --> 00:10:03,800 Speaker 1: Daniel and Jorge dot com. We'll send you the questions 180 00:10:03,840 --> 00:10:06,160 Speaker 1: back over email. You can record the answers in your 181 00:10:06,240 --> 00:10:08,959 Speaker 1: very own home. It's easy, it's fun. Don't be shy. 182 00:10:09,080 --> 00:10:11,840 Speaker 1: So pop quiz. Why do you think black holes glow? 183 00:10:12,720 --> 00:10:15,480 Speaker 1: That's what people had to say. They closer brightly because 184 00:10:15,520 --> 00:10:19,959 Speaker 1: they're sucking all the surrounding light and everything around it, 185 00:10:20,800 --> 00:10:25,840 Speaker 1: so you have spires of light basically coming in at 186 00:10:25,840 --> 00:10:29,280 Speaker 1: one point, and that's why it's so bright. I don't 187 00:10:29,480 --> 00:10:33,800 Speaker 1: think that the black holes are glowing like itself, definitely 188 00:10:33,800 --> 00:10:36,880 Speaker 1: not at the center, since there's a gravitation of bood 189 00:10:36,920 --> 00:10:40,520 Speaker 1: there is so great that not even light can escape it. However, 190 00:10:40,640 --> 00:10:44,920 Speaker 1: you can potentially detect material around them, and like gas 191 00:10:44,920 --> 00:10:48,800 Speaker 1: and dust spinning around it, throwing off hot material, and 192 00:10:49,320 --> 00:10:53,920 Speaker 1: when emitting radiation like X rays and as a matter 193 00:10:53,960 --> 00:10:56,480 Speaker 1: of falls into the hole, it can be detected and 194 00:10:56,520 --> 00:11:01,400 Speaker 1: it can actually brightly or glow bright. I think there's 195 00:11:01,440 --> 00:11:05,200 Speaker 1: so much energy imparted into the material that's swarming around 196 00:11:05,240 --> 00:11:11,679 Speaker 1: them that um, somehow that energy turns into light excited 197 00:11:12,520 --> 00:11:15,840 Speaker 1: electrons and stuff like that. And I also know that 198 00:11:15,880 --> 00:11:20,240 Speaker 1: they can focus material and jetted out, and that material 199 00:11:20,800 --> 00:11:23,440 Speaker 1: goes out and interacts with the dust and stuff around 200 00:11:23,480 --> 00:11:26,079 Speaker 1: the black holes and bumps them up into a light 201 00:11:26,160 --> 00:11:31,600 Speaker 1: emitting excited state like an emission nebula. Okay, so black 202 00:11:31,720 --> 00:11:37,840 Speaker 1: holes they're not glowing. I think that the light is 203 00:11:37,920 --> 00:11:44,200 Speaker 1: getting refracted around them, it's getting bounced off, and so 204 00:11:44,720 --> 00:11:47,880 Speaker 1: it's not the black hole that's glowing. But it's an 205 00:11:47,880 --> 00:11:52,400 Speaker 1: illusion almost because they're I believe they're called acretion disks, 206 00:11:52,559 --> 00:11:56,960 Speaker 1: give off just a ton of heat because they're swirling 207 00:11:56,960 --> 00:12:02,000 Speaker 1: around at almost light speed something like that. I think, 208 00:12:02,440 --> 00:12:08,720 Speaker 1: not the black hole itself glows. Uh, what it glows 209 00:12:08,880 --> 00:12:13,679 Speaker 1: would be the creation disks where the older gases a 210 00:12:13,840 --> 00:12:20,280 Speaker 1: Dutch speed amid energy, and also might be the curs 211 00:12:20,720 --> 00:12:24,560 Speaker 1: some black holes type qus. That would be also a 212 00:12:24,679 --> 00:12:29,120 Speaker 1: reason why a black hole looks so brightly. I think 213 00:12:29,160 --> 00:12:31,040 Speaker 1: this has to deal with black holes that are feeding, 214 00:12:31,360 --> 00:12:34,520 Speaker 1: that actively feeding off of other stars or other objects. 215 00:12:34,559 --> 00:12:36,760 Speaker 1: I think when they're feeding, it brings in everything on 216 00:12:36,920 --> 00:12:39,600 Speaker 1: that creation disk, and everything heats up and creates like 217 00:12:39,760 --> 00:12:43,080 Speaker 1: plasmas where like they're stripping, you know, stripping everything down 218 00:12:43,120 --> 00:12:46,120 Speaker 1: to its elemental form. And I think it causes a 219 00:12:46,120 --> 00:12:49,920 Speaker 1: lot of activity like the electromagnetic field. So like I know, 220 00:12:50,160 --> 00:12:53,120 Speaker 1: X black holes give off X rays and they give 221 00:12:53,120 --> 00:12:55,320 Speaker 1: off gamma rays, and they give off these strong energies 222 00:12:55,400 --> 00:12:57,440 Speaker 1: that we can measure here on Earth. So it has 223 00:12:57,440 --> 00:12:59,360 Speaker 1: to be because their feet. The black holes give off 224 00:12:59,400 --> 00:13:02,600 Speaker 1: energy because they're feeding off of surrounding objects and causing 225 00:13:02,640 --> 00:13:04,520 Speaker 1: a lot of activity in ways that we can measure 226 00:13:04,559 --> 00:13:06,920 Speaker 1: here on Earth. All Right, some pretty good answers. A 227 00:13:06,920 --> 00:13:09,199 Speaker 1: lot of people seem to be confident and familiar about 228 00:13:09,200 --> 00:13:11,920 Speaker 1: this topic, almost like we've been talking about black holes 229 00:13:11,960 --> 00:13:16,600 Speaker 1: for quite a while, Yeah, for three hundred episodes. It 230 00:13:16,640 --> 00:13:18,680 Speaker 1: is a popular topic, and a lot of people hit 231 00:13:18,760 --> 00:13:21,280 Speaker 1: on a really important point, which is that a lot 232 00:13:21,360 --> 00:13:23,680 Speaker 1: of the radiation from black holes doesn't come from the 233 00:13:23,760 --> 00:13:27,360 Speaker 1: actual black hole within the event horizon itself, but from 234 00:13:27,400 --> 00:13:30,240 Speaker 1: the stuff that's around the black hole, the impact of 235 00:13:30,280 --> 00:13:33,800 Speaker 1: the black hole on the neighboring objects, right, Yeah, or 236 00:13:33,840 --> 00:13:36,120 Speaker 1: maybe they read both of our books and our two 237 00:13:36,160 --> 00:13:38,960 Speaker 1: books we have no idea and frequently asked questions about 238 00:13:38,960 --> 00:13:41,440 Speaker 1: the universe, we do talk about black holes, and and 239 00:13:41,480 --> 00:13:44,480 Speaker 1: one when we get really into black holes, like literally, Yeah, 240 00:13:44,520 --> 00:13:47,240 Speaker 1: we talked about what it would be like to fall 241 00:13:47,280 --> 00:13:50,120 Speaker 1: into a black hole, whether you could survive, and what 242 00:13:50,160 --> 00:13:52,960 Speaker 1: you should pack along the way and what you experience. 243 00:13:53,040 --> 00:13:56,000 Speaker 1: So please check out our books, our second book now 244 00:13:56,000 --> 00:13:58,840 Speaker 1: out frequently asked questions about the universe, but in this 245 00:13:58,880 --> 00:14:01,800 Speaker 1: case we're talking about why they glow. And a lot 246 00:14:01,800 --> 00:14:05,320 Speaker 1: of people seem to associated with not the black hole itself, 247 00:14:05,360 --> 00:14:07,960 Speaker 1: but sort of the things around it, or at least 248 00:14:07,960 --> 00:14:10,800 Speaker 1: what's happening around it in terms of the space distortion. Yeah, 249 00:14:10,800 --> 00:14:13,440 Speaker 1: and there's several effects here that are important to pull apart. 250 00:14:13,840 --> 00:14:17,760 Speaker 1: One is weather black holes actually do glow themselves, and 251 00:14:17,800 --> 00:14:20,840 Speaker 1: the second are how they make things around them glow. 252 00:14:21,080 --> 00:14:23,480 Speaker 1: But there's more than just the accretion disc there, which 253 00:14:23,520 --> 00:14:25,800 Speaker 1: we'll get into later. But first let's talk about the 254 00:14:25,800 --> 00:14:29,000 Speaker 1: black holes themselves. Most people said black holes don't glow 255 00:14:29,080 --> 00:14:33,280 Speaker 1: because they're black. That's mostly true, but not actually a 256 00:14:33,400 --> 00:14:36,240 Speaker 1: hundred percent true. A black hole, even if it had 257 00:14:36,280 --> 00:14:39,360 Speaker 1: nothing around it, just sitting in empty space, wouldn't be 258 00:14:39,520 --> 00:14:42,760 Speaker 1: a hundred percent black. They do give off a very 259 00:14:42,800 --> 00:14:47,040 Speaker 1: small amount of radiation. Yeah, super interesting, and so let's 260 00:14:47,200 --> 00:14:51,000 Speaker 1: dive into this topic and make it glow. So, Daniel, 261 00:14:51,120 --> 00:14:53,800 Speaker 1: I guess to refresh everyone out there, what is exactly 262 00:14:53,880 --> 00:14:55,800 Speaker 1: a black hole. A black hole is a region of 263 00:14:55,880 --> 00:14:59,080 Speaker 1: space where it is curved so much that not even 264 00:14:59,160 --> 00:15:01,440 Speaker 1: light can escape. So this portion of space is then 265 00:15:01,520 --> 00:15:05,480 Speaker 1: encircled by something we call an event horizon. Any object 266 00:15:05,640 --> 00:15:09,240 Speaker 1: or photon or particle which falls within this event horizon 267 00:15:09,560 --> 00:15:12,680 Speaker 1: is trapped forever it moves towards the center of the 268 00:15:12,720 --> 00:15:15,240 Speaker 1: black hole. And this event horizon is not like a 269 00:15:15,280 --> 00:15:19,080 Speaker 1: physical barrier. There's nothing, there's nobody to greet you or 270 00:15:19,120 --> 00:15:21,600 Speaker 1: to say hello and welcome to the black hole. It's 271 00:15:21,640 --> 00:15:24,080 Speaker 1: just sort of a region of space which if you pass, 272 00:15:24,560 --> 00:15:27,280 Speaker 1: you will never escape. So these black holes are these 273 00:15:27,320 --> 00:15:29,800 Speaker 1: curved regions of space time, as we said earlier, sort 274 00:15:29,800 --> 00:15:32,640 Speaker 1: of detached from the rest of the universe, and they 275 00:15:32,680 --> 00:15:35,360 Speaker 1: form when stars collapse, or sometimes they form at the 276 00:15:35,400 --> 00:15:38,800 Speaker 1: center of galaxies. And they can be extraordinarily massive. Yeah, 277 00:15:38,960 --> 00:15:40,560 Speaker 1: and we've talked about how you can have them of 278 00:15:40,680 --> 00:15:43,320 Speaker 1: any size. You can have tiny, little mini black holes, 279 00:15:43,400 --> 00:15:45,720 Speaker 1: or you can have giant black holes that are billions 280 00:15:45,720 --> 00:15:49,040 Speaker 1: of times more massive than our sun. And like you said, 281 00:15:49,080 --> 00:15:52,720 Speaker 1: there's sort of regions of space where suddenly, like everywhere 282 00:15:52,720 --> 00:15:55,160 Speaker 1: you can go can only go take you inside of 283 00:15:55,160 --> 00:15:57,440 Speaker 1: the black hole, right, instead of a weird thing to 284 00:15:57,480 --> 00:15:59,720 Speaker 1: think about that space can bend that way. Yeah, and 285 00:15:59,760 --> 00:16:01,560 Speaker 1: space says something you might think of. It's just sort 286 00:16:01,600 --> 00:16:04,520 Speaker 1: of like the backdrop of the universe, like the stage 287 00:16:04,520 --> 00:16:06,880 Speaker 1: on which events happen. But we now know that it's 288 00:16:06,960 --> 00:16:09,760 Speaker 1: much more interesting and it can do fascinating things like 289 00:16:09,960 --> 00:16:12,760 Speaker 1: bend and twist. Most of the time you don't notice 290 00:16:12,800 --> 00:16:15,880 Speaker 1: that gravity, turns out is an effect of space is curvature, 291 00:16:15,920 --> 00:16:17,960 Speaker 1: so you feel that every day when you walk around 292 00:16:17,960 --> 00:16:20,000 Speaker 1: on the planet. But mostly things seem to move in 293 00:16:20,040 --> 00:16:22,080 Speaker 1: a way that makes sense to you. But a black 294 00:16:22,080 --> 00:16:24,880 Speaker 1: holes like the extreme version of that, like crank it 295 00:16:24,960 --> 00:16:27,840 Speaker 1: up to eleven, where things get really distorted and the 296 00:16:27,880 --> 00:16:30,520 Speaker 1: shape of space like dominates. You know, it's the thing 297 00:16:30,520 --> 00:16:34,280 Speaker 1: that determines everything that happens. Right, and I guess specifically 298 00:16:34,280 --> 00:16:36,520 Speaker 1: you mean like the shape of space time, right, Like 299 00:16:36,560 --> 00:16:39,800 Speaker 1: maybe it's not so much space but space time, meaning 300 00:16:39,880 --> 00:16:41,920 Speaker 1: like where you will be in the future in in 301 00:16:41,920 --> 00:16:44,560 Speaker 1: that space. Yeah, we bundle space and time together into 302 00:16:44,600 --> 00:16:47,280 Speaker 1: a sort of a four dimensional object. One thing that's 303 00:16:47,280 --> 00:16:51,240 Speaker 1: really fascinating is that inside the black hole, space becomes 304 00:16:51,360 --> 00:16:54,120 Speaker 1: one directional. You can only move towards the center of it. 305 00:16:54,480 --> 00:16:57,040 Speaker 1: That seems a little counter intuitive until you remember that 306 00:16:57,120 --> 00:17:00,280 Speaker 1: outside the black hole, time is already one direction the 307 00:17:00,280 --> 00:17:03,040 Speaker 1: way you can only move forwards in time in that 308 00:17:03,200 --> 00:17:07,320 Speaker 1: same way. Inside the black hole, every path leads towards 309 00:17:07,400 --> 00:17:11,000 Speaker 1: the center. The future of every particle trajectory inside a 310 00:17:11,000 --> 00:17:13,919 Speaker 1: black hole hits the singularity. So that's what we mean 311 00:17:13,960 --> 00:17:16,600 Speaker 1: when we say that space is one directional, and that's 312 00:17:16,640 --> 00:17:20,320 Speaker 1: directly because space is curved so much so once you're 313 00:17:20,359 --> 00:17:22,360 Speaker 1: inside of the event of horizon of a black hole, 314 00:17:22,400 --> 00:17:24,239 Speaker 1: you can't get out, and not even you can't even 315 00:17:24,240 --> 00:17:26,280 Speaker 1: shoot a laser out of it because the light from 316 00:17:26,280 --> 00:17:28,720 Speaker 1: the laser, which just should back around and come back 317 00:17:28,760 --> 00:17:30,439 Speaker 1: to the center of the black hole. And so it's 318 00:17:30,480 --> 00:17:32,760 Speaker 1: sort of surprising that a black hole can glow then, 319 00:17:32,920 --> 00:17:35,720 Speaker 1: So like, how do they glow? How can they give 320 00:17:35,760 --> 00:17:39,080 Speaker 1: off or emit anything? Yeah, black holes can glow, and 321 00:17:39,119 --> 00:17:42,159 Speaker 1: the way they do that is by Hawking radiation. Hawking 322 00:17:42,240 --> 00:17:46,119 Speaker 1: radiation is the recognition that black holes have a temperature, 323 00:17:46,240 --> 00:17:49,480 Speaker 1: like everything else in the universe almost has a temperature. 324 00:17:49,520 --> 00:17:51,640 Speaker 1: I have a temperature, You have a temperature, the Sun 325 00:17:51,720 --> 00:17:54,720 Speaker 1: as a temperature, and everything that has a temperature and 326 00:17:54,800 --> 00:17:59,480 Speaker 1: has electromagnetic interactions glows just sort of like gives off heat. 327 00:17:59,760 --> 00:18:02,680 Speaker 1: The for example, a pie sitting on your counter cools 328 00:18:02,720 --> 00:18:05,840 Speaker 1: off it does that by radiating away some of its energy. 329 00:18:06,000 --> 00:18:08,400 Speaker 1: So this is called black body radiation, and we talked 330 00:18:08,400 --> 00:18:11,000 Speaker 1: about this on the podcast recently. How everything with a 331 00:18:11,040 --> 00:18:15,119 Speaker 1: temperature glows. So Stephen Hawking realized that black holes also 332 00:18:15,240 --> 00:18:18,359 Speaker 1: have a temperature. They're not at absolute zero, which means 333 00:18:18,440 --> 00:18:21,159 Speaker 1: that they must glow, and so he speculated that they 334 00:18:21,240 --> 00:18:25,640 Speaker 1: must give off very faint radiation, meaning little particles created 335 00:18:25,720 --> 00:18:28,840 Speaker 1: just outside the black hole that somehow steals some of 336 00:18:28,880 --> 00:18:31,600 Speaker 1: its energy. And there are various sort of pop side 337 00:18:31,600 --> 00:18:34,399 Speaker 1: descriptions of how Hawking radiation happens at the end of 338 00:18:34,440 --> 00:18:36,840 Speaker 1: a black hole, but it's important to understand that none 339 00:18:36,840 --> 00:18:40,280 Speaker 1: of those are really very accurate. We have no accurate 340 00:18:40,400 --> 00:18:44,199 Speaker 1: microscopic picture of how Hawking radiation really happens because it 341 00:18:44,240 --> 00:18:47,119 Speaker 1: requires the theory of how gravity affects particles, and we 342 00:18:47,240 --> 00:18:50,480 Speaker 1: just don't have that theory. We don't know what quantum 343 00:18:50,520 --> 00:18:53,720 Speaker 1: gravity is. We can't describe the effect of gravity on 344 00:18:53,760 --> 00:18:57,040 Speaker 1: tiny particles. There are some sort of hand wavy explanations 345 00:18:57,080 --> 00:18:58,879 Speaker 1: to give you a sense of how it works, but 346 00:18:58,920 --> 00:19:01,879 Speaker 1: it's important to understand that mostly it's a statistical argument 347 00:19:01,880 --> 00:19:04,720 Speaker 1: about the temperature of black holes, right, Yeah, it's pretty 348 00:19:04,720 --> 00:19:08,120 Speaker 1: cool to think about hot black holes or cool black holes. 349 00:19:08,359 --> 00:19:10,200 Speaker 1: But I guess, you know, most people are sort of 350 00:19:10,240 --> 00:19:12,399 Speaker 1: familiar with a pie in your desk is kind of 351 00:19:12,440 --> 00:19:15,320 Speaker 1: emanating heat through the air. But I think what's interesting 352 00:19:15,359 --> 00:19:17,120 Speaker 1: is that even if you put that pot pie out 353 00:19:17,119 --> 00:19:19,800 Speaker 1: in space where it's not touching any air, it would 354 00:19:19,800 --> 00:19:24,120 Speaker 1: still radiate heat in the form of infrared light, right, yeah, 355 00:19:24,240 --> 00:19:26,880 Speaker 1: or visible light depending on the temperature. Like the Sun. 356 00:19:27,080 --> 00:19:29,720 Speaker 1: There's a huge vacuum between us and the Sun, but 357 00:19:29,800 --> 00:19:31,600 Speaker 1: it's still able to warm you up on a nice 358 00:19:31,640 --> 00:19:35,000 Speaker 1: toasty southern California morning, and it does that by radiating 359 00:19:35,000 --> 00:19:38,040 Speaker 1: away its energy via photons, and the frequency of those 360 00:19:38,080 --> 00:19:41,320 Speaker 1: photons depends on the temperature of the object. So the 361 00:19:41,359 --> 00:19:44,120 Speaker 1: Sun glows in the visible spectrum the Earth and you 362 00:19:44,240 --> 00:19:47,960 Speaker 1: glow in the infrared, as does that pie. Black holes 363 00:19:48,240 --> 00:19:51,359 Speaker 1: are very very cold, so they glow in very very 364 00:19:51,400 --> 00:19:55,119 Speaker 1: long wavelengths. Yeah, but it's kind of interesting because you 365 00:19:55,160 --> 00:19:57,800 Speaker 1: know that hot pie in space is probably you know, 366 00:19:57,880 --> 00:20:00,800 Speaker 1: the way that it's emanating light is that you know, 367 00:20:00,880 --> 00:20:03,840 Speaker 1: the electrons and the surface of the pie are excited 368 00:20:03,960 --> 00:20:06,280 Speaker 1: and they dropped down an energy level maybe and they 369 00:20:06,320 --> 00:20:08,640 Speaker 1: admit a photon in the infrared, so you can sort 370 00:20:08,640 --> 00:20:11,879 Speaker 1: of imagine that mechanism for giving off energy. But a 371 00:20:11,880 --> 00:20:14,440 Speaker 1: black hole is kind of weird, right, because the surface 372 00:20:14,440 --> 00:20:16,560 Speaker 1: of a black hole is not actually like a surface, 373 00:20:16,680 --> 00:20:19,639 Speaker 1: and it's not actually like stuff, right. It's weird to 374 00:20:19,680 --> 00:20:22,320 Speaker 1: think that it can just emanate heat or light out 375 00:20:22,359 --> 00:20:26,199 Speaker 1: of basically, you know, a hole own space exactly. It 376 00:20:26,280 --> 00:20:28,320 Speaker 1: is very weird, And as you said, we have a 377 00:20:28,359 --> 00:20:30,879 Speaker 1: pretty good understanding for how that happens for pies, like 378 00:20:30,920 --> 00:20:33,600 Speaker 1: the physics of pies, we have a pretty solid understanding, 379 00:20:33,640 --> 00:20:37,760 Speaker 1: Like quantum pie dynamics pretty well understood, but that's because 380 00:20:37,760 --> 00:20:40,439 Speaker 1: we understand that kind of matter and the forces of 381 00:20:40,480 --> 00:20:43,520 Speaker 1: gravity there are pretty weak. But in the case of 382 00:20:43,520 --> 00:20:46,480 Speaker 1: a black hole, we don't really understand what happens to 383 00:20:46,640 --> 00:20:50,040 Speaker 1: electrons very very close to the event horizon, or virtual 384 00:20:50,080 --> 00:20:53,320 Speaker 1: particles created near the event horizon. We just don't have 385 00:20:53,359 --> 00:20:56,200 Speaker 1: an understanding of it. Neither does Stephen Hawking. He doesn't 386 00:20:56,240 --> 00:20:58,560 Speaker 1: have a theory of quantum gravity. What he did was 387 00:20:58,600 --> 00:21:01,840 Speaker 1: make us sort of like semi classical theory of gravity, 388 00:21:01,880 --> 00:21:04,720 Speaker 1: like a sort of patch together concept of you know, 389 00:21:04,800 --> 00:21:07,639 Speaker 1: using bits and pieces to sort of approximate what some 390 00:21:07,800 --> 00:21:10,560 Speaker 1: elements of quantum gravity might look like, and using that 391 00:21:10,640 --> 00:21:12,959 Speaker 1: you can make a sort of hand wavy picture. You know. 392 00:21:13,000 --> 00:21:17,200 Speaker 1: The picture is that you have virtual particles created outside 393 00:21:17,280 --> 00:21:20,240 Speaker 1: the event horizon, not within the black hole, but outside, 394 00:21:20,520 --> 00:21:23,439 Speaker 1: and those particles can pick up some extra energy because 395 00:21:23,480 --> 00:21:26,679 Speaker 1: of the incredible gravity of the black hole. Remember that 396 00:21:26,760 --> 00:21:29,280 Speaker 1: black holes, even though they have this event horizon, they 397 00:21:29,280 --> 00:21:32,199 Speaker 1: can affect things outside the event horizon. Right, Just like 398 00:21:32,240 --> 00:21:34,320 Speaker 1: the Sun pulls on you with its gravity from very 399 00:21:34,400 --> 00:21:36,600 Speaker 1: very far away, a black hole can also do that, 400 00:21:36,680 --> 00:21:40,480 Speaker 1: pulling on you with its gravity and giving you extra energy. 401 00:21:40,600 --> 00:21:43,399 Speaker 1: When it does so, it loses that energy. It gives 402 00:21:43,400 --> 00:21:45,800 Speaker 1: that energy to one of those particles. So if a 403 00:21:45,840 --> 00:21:49,080 Speaker 1: particles created near a black hole and then boosted by 404 00:21:49,200 --> 00:21:51,880 Speaker 1: the energy of that black hole, when it leaves, it's 405 00:21:51,960 --> 00:21:54,840 Speaker 1: taking away some of the energy of that black hole. 406 00:21:55,280 --> 00:21:58,480 Speaker 1: So again, this is a hand wavy, probably not accurate 407 00:21:58,480 --> 00:22:01,600 Speaker 1: description of how hawking really is generated because we don't 408 00:22:01,640 --> 00:22:04,760 Speaker 1: have a solid understanding of quantum mechanics and gravity and 409 00:22:04,760 --> 00:22:06,920 Speaker 1: how they play well together. All right, well, let's dig 410 00:22:06,960 --> 00:22:09,480 Speaker 1: into this hawking radiation a little bit more, and then 411 00:22:09,520 --> 00:22:11,560 Speaker 1: also what are some of the other ways that black 412 00:22:11,560 --> 00:22:14,879 Speaker 1: holes glow. Some of them are pretty dramatic and maybe 413 00:22:14,920 --> 00:22:17,480 Speaker 1: even the brightest objects in the universe. So let's get 414 00:22:17,480 --> 00:22:19,679 Speaker 1: into all that, but first let's take a quick break. 415 00:22:32,280 --> 00:22:35,040 Speaker 1: All right, we're talking about glowing black holes, which is 416 00:22:35,080 --> 00:22:37,320 Speaker 1: sort of sounds like an oxymoron, sort of like a 417 00:22:37,320 --> 00:22:39,439 Speaker 1: bright dark object. I think it's sort of cool that 418 00:22:39,480 --> 00:22:41,800 Speaker 1: we think about black holes is like hidden and hard 419 00:22:41,880 --> 00:22:44,600 Speaker 1: to find, and it took us decades to discover them. 420 00:22:44,640 --> 00:22:47,240 Speaker 1: When it turns out, they're sort of like screaming about 421 00:22:47,240 --> 00:22:49,560 Speaker 1: their existence all the way through the universe, Like they 422 00:22:49,560 --> 00:22:52,720 Speaker 1: are not being shot. They're being very very obvious. They're 423 00:22:52,880 --> 00:22:57,200 Speaker 1: kind of matches. Actually, it's like, can you quiet down, please, 424 00:22:57,240 --> 00:22:59,960 Speaker 1: we're trying to study black holes. Settle down, settle down. 425 00:23:00,400 --> 00:23:02,959 Speaker 1: We know you're cool, but you know, you don't need 426 00:23:02,960 --> 00:23:05,119 Speaker 1: to prove yourself. And that's what makes it ironic is 427 00:23:05,119 --> 00:23:07,640 Speaker 1: that they are so bright and so intense and so 428 00:23:07,680 --> 00:23:11,000 Speaker 1: crazy that people sort of overlooked them as candidates for 429 00:23:11,040 --> 00:23:13,640 Speaker 1: black holes for a long time. Interesting, well, we were 430 00:23:13,680 --> 00:23:17,119 Speaker 1: talking about hawking radiation, which is sort of the glow 431 00:23:17,320 --> 00:23:20,600 Speaker 1: or a small glow that black holes have that happens 432 00:23:20,600 --> 00:23:23,600 Speaker 1: to about the boundary of the black hole due to 433 00:23:23,720 --> 00:23:26,359 Speaker 1: a quantum particles appearing and things like that. But I 434 00:23:26,359 --> 00:23:28,480 Speaker 1: guess the question is of all of this is theoretical, 435 00:23:28,520 --> 00:23:31,640 Speaker 1: we don't actually know how it emits hawking radiation, and 436 00:23:31,800 --> 00:23:34,760 Speaker 1: I'm guessing we've never seen this hawking radiation being admitted 437 00:23:34,800 --> 00:23:37,480 Speaker 1: because we barely have pictures of black holes, Like, how 438 00:23:37,480 --> 00:23:39,600 Speaker 1: do we know hawking radiation is a real thing? How 439 00:23:39,600 --> 00:23:42,000 Speaker 1: do we know hawking radiation is a real thing? Simple answer, 440 00:23:42,119 --> 00:23:46,639 Speaker 1: we don't. It's theoretical, it's predicted. It makes more sense 441 00:23:46,800 --> 00:23:49,640 Speaker 1: than black holes and not giving off hawking radiation because 442 00:23:49,640 --> 00:23:51,920 Speaker 1: that would require them to be an absolute zero, and 443 00:23:51,960 --> 00:23:53,760 Speaker 1: it would be in contradiction with lots of things we 444 00:23:53,800 --> 00:23:56,320 Speaker 1: know about, like entropy. Black holes have to have a 445 00:23:56,359 --> 00:23:59,320 Speaker 1: temperature because I have to have micro states inside, because 446 00:23:59,359 --> 00:24:02,520 Speaker 1: they have to receive eve information when something falls into 447 00:24:02,560 --> 00:24:06,320 Speaker 1: a black hole, they're gathering quantum information, and in order 448 00:24:06,320 --> 00:24:09,240 Speaker 1: to have that information, they have to have some entropy, 449 00:24:09,280 --> 00:24:12,479 Speaker 1: and entropy means temperature. So again it's sort of an 450 00:24:12,560 --> 00:24:15,960 Speaker 1: argument from statistical mechanics. But you're right, we haven't observed 451 00:24:16,000 --> 00:24:19,000 Speaker 1: it directly, but it's opened up a really rich vein 452 00:24:19,200 --> 00:24:21,719 Speaker 1: of area for people to explore it's like given us 453 00:24:21,920 --> 00:24:24,280 Speaker 1: a crack in the facade of black holes where people 454 00:24:24,320 --> 00:24:27,320 Speaker 1: can jump in and then explore more properties of black holes. 455 00:24:27,560 --> 00:24:31,040 Speaker 1: But it's not something that we have confirmed experimentally. It's 456 00:24:31,320 --> 00:24:34,960 Speaker 1: very very faint, really really large black holes emit very 457 00:24:35,119 --> 00:24:39,119 Speaker 1: very very faint Hawking radiation. It's actually the smaller black 458 00:24:39,119 --> 00:24:42,240 Speaker 1: holes that emit more Hawking radiation, and they would glow 459 00:24:42,359 --> 00:24:45,280 Speaker 1: very brightly, and just before a black hole like evaporates 460 00:24:45,280 --> 00:24:48,440 Speaker 1: into nothingness, it would be quite bright, and we've looked 461 00:24:48,440 --> 00:24:51,200 Speaker 1: for that, but we haven't seen any evaporating black holes 462 00:24:51,240 --> 00:24:54,560 Speaker 1: in the universe. I see interesting. So it's sort of 463 00:24:54,600 --> 00:24:57,359 Speaker 1: theoretical and we think it's sort of glows by this 464 00:24:57,440 --> 00:24:59,560 Speaker 1: Hawking radiation, but it's sort of what you're saying. It 465 00:24:59,640 --> 00:25:02,160 Speaker 1: makes ends based on our current theories. But our current 466 00:25:02,200 --> 00:25:05,600 Speaker 1: theories sort of don't necessarily work inside of a black 467 00:25:05,600 --> 00:25:07,880 Speaker 1: hole or with a black hole, right, So there might 468 00:25:07,920 --> 00:25:10,560 Speaker 1: still be surprises about this whole thing. Oh absolutely, our 469 00:25:10,600 --> 00:25:15,240 Speaker 1: current theories almost certainly wrong. And later somebody smarter, maybe 470 00:25:15,320 --> 00:25:17,920 Speaker 1: one of our podcast listeners who's going to go into 471 00:25:17,920 --> 00:25:20,440 Speaker 1: this field, will come along with a full fledged theory 472 00:25:20,440 --> 00:25:23,560 Speaker 1: of quantum gravity, and it might be that that theory 473 00:25:23,600 --> 00:25:26,600 Speaker 1: agrees with Hawkings theories and you know this concept of 474 00:25:26,600 --> 00:25:29,119 Speaker 1: Hawking radiation and black hole temperatures. But it might be 475 00:25:29,160 --> 00:25:31,480 Speaker 1: that it doesn't and that there are surprises. And that's 476 00:25:31,520 --> 00:25:33,399 Speaker 1: exactly why we go out and we look at these 477 00:25:33,440 --> 00:25:35,640 Speaker 1: black holes and we studied them and we take pictures 478 00:25:35,920 --> 00:25:39,000 Speaker 1: because the universe is filled with surprises and is always 479 00:25:39,000 --> 00:25:41,800 Speaker 1: confronting us with different stories than the ones we were 480 00:25:41,800 --> 00:25:45,240 Speaker 1: telling ourselves in our head. Yeah, so it's a hypothetical 481 00:25:45,720 --> 00:25:48,520 Speaker 1: guest theory based on a theory we think. We know 482 00:25:48,560 --> 00:25:51,960 Speaker 1: it's wrong. It's what you're saying, also known as doing 483 00:25:51,960 --> 00:25:55,639 Speaker 1: our best well. Stephen Hawking is usually pretty right about stuff. 484 00:25:55,800 --> 00:25:58,920 Speaker 1: So these black holes glowing and emanating sort of a 485 00:25:59,040 --> 00:26:03,120 Speaker 1: slow of heat or radiation is one way that black 486 00:26:03,119 --> 00:26:05,480 Speaker 1: holes can glow. But they can also glow more dramatically, 487 00:26:05,600 --> 00:26:08,520 Speaker 1: right like a big time. Yes, they can glow very 488 00:26:08,640 --> 00:26:12,080 Speaker 1: dramatically because they have very strong effects on the gas 489 00:26:12,160 --> 00:26:14,800 Speaker 1: around them. The way the black holes grows that they 490 00:26:14,920 --> 00:26:18,639 Speaker 1: gobble gas and stars in their vicinity and before the 491 00:26:18,680 --> 00:26:21,440 Speaker 1: things fall into them, they swirl around for a while 492 00:26:21,560 --> 00:26:24,040 Speaker 1: because they have angular momentum, just the way the Earth 493 00:26:24,119 --> 00:26:26,240 Speaker 1: is going around the Sun doesn't just fall straight in. 494 00:26:26,440 --> 00:26:28,639 Speaker 1: Things around a black hole swirl around for a while 495 00:26:29,000 --> 00:26:31,240 Speaker 1: before they bump into each other and eventually fall in. 496 00:26:31,480 --> 00:26:34,240 Speaker 1: And that bumping into each other is very intense because 497 00:26:34,280 --> 00:26:36,560 Speaker 1: the gravity is very intense. So if you have a 498 00:26:36,600 --> 00:26:39,520 Speaker 1: huge cloud of gas around a black hole, there's a 499 00:26:39,520 --> 00:26:42,840 Speaker 1: lot of gravitational friction and that heats it up and 500 00:26:42,960 --> 00:26:47,280 Speaker 1: that glows and they can create incredible sources of light. Yeah, 501 00:26:47,600 --> 00:26:51,280 Speaker 1: I guess that's kind of maybe hard for people to grasp, right, Like, 502 00:26:51,440 --> 00:26:53,760 Speaker 1: you know, the Earth is orbiting around the Sun, but 503 00:26:54,000 --> 00:26:56,359 Speaker 1: we're not sort of glowing or we're not we're not 504 00:26:56,400 --> 00:27:00,480 Speaker 1: getting sort of shredded and rub into bright bright So 505 00:27:00,800 --> 00:27:04,040 Speaker 1: maybe is it because black holes are so intense and 506 00:27:04,080 --> 00:27:06,920 Speaker 1: the gravity around the black holes is like super extra 507 00:27:07,000 --> 00:27:10,000 Speaker 1: intense that things just get shredded even if they're just 508 00:27:10,119 --> 00:27:12,359 Speaker 1: going around them. Absolutely, But the Earth does have that 509 00:27:12,400 --> 00:27:15,400 Speaker 1: effect a little bit, Like the effect of the Moon 510 00:27:15,680 --> 00:27:17,840 Speaker 1: is to sort of squeeze the Earth a little bit 511 00:27:18,080 --> 00:27:20,800 Speaker 1: and it like massages the Earth's oceans. Or if you 512 00:27:20,880 --> 00:27:24,240 Speaker 1: were a moon going around Jupiter for example, Io, why 513 00:27:24,280 --> 00:27:27,040 Speaker 1: are those moons so hot on the inside because of 514 00:27:27,080 --> 00:27:31,359 Speaker 1: the gravitational squeezing from Jupiter, and so the Sun is 515 00:27:31,400 --> 00:27:34,080 Speaker 1: doing that also to the Earth. So if the Sun 516 00:27:34,160 --> 00:27:37,000 Speaker 1: was larger and more massive and the Earth was closer 517 00:27:37,040 --> 00:27:40,080 Speaker 1: to it than those tidal forces would really heat up 518 00:27:40,119 --> 00:27:42,440 Speaker 1: the center of the Earth. And so black holes are 519 00:27:42,640 --> 00:27:45,640 Speaker 1: much much more intense gravitationally, and these accretion discs are 520 00:27:45,760 --> 00:27:48,880 Speaker 1: much much closer to them, and so this gravitational sort 521 00:27:48,920 --> 00:27:52,000 Speaker 1: of squeezing and tugging heats them up. It's more of 522 00:27:52,000 --> 00:27:55,119 Speaker 1: a gravitational pulling, right, Like the Moon is not so 523 00:27:55,200 --> 00:27:57,800 Speaker 1: much squeezing the water on Earth, but it's sort of 524 00:27:57,840 --> 00:28:00,200 Speaker 1: like pulling on it more in one side and the other, 525 00:28:00,240 --> 00:28:04,080 Speaker 1: and that's what's causing the tidal forces, right. Yeah, Gravity 526 00:28:04,160 --> 00:28:07,080 Speaker 1: depends very strongly on the distance, and so the bits 527 00:28:07,119 --> 00:28:08,920 Speaker 1: of the Earth that are closer to the Moon get 528 00:28:09,000 --> 00:28:11,159 Speaker 1: pulled on harder than the bits of the Earth that 529 00:28:11,200 --> 00:28:13,680 Speaker 1: are further from the Moon. And so the result is 530 00:28:13,720 --> 00:28:16,119 Speaker 1: the Moon is basically trying to pull the Earth apart 531 00:28:16,240 --> 00:28:19,159 Speaker 1: because it's pulling on one side harder than the other side. 532 00:28:19,480 --> 00:28:21,880 Speaker 1: The same with Jupiter and its moons. You can think 533 00:28:21,880 --> 00:28:23,560 Speaker 1: of it like taking a piece of chewing gum and 534 00:28:23,600 --> 00:28:27,560 Speaker 1: pulling on one end only it stretches it out. But 535 00:28:27,600 --> 00:28:29,399 Speaker 1: then if that chewing gum is spinning, then you're like 536 00:28:29,520 --> 00:28:32,159 Speaker 1: constantly stretching out different parts of it, so you're keeping 537 00:28:32,160 --> 00:28:34,920 Speaker 1: it warm. You're you're like massaging it like a dough, 538 00:28:34,960 --> 00:28:36,359 Speaker 1: like if you need a dough. It it sort of 539 00:28:36,400 --> 00:28:38,520 Speaker 1: heats up a little bit, right, and now it's spinning 540 00:28:38,520 --> 00:28:42,320 Speaker 1: like a pizza dough where we're a little hungry here. 541 00:28:42,800 --> 00:28:44,320 Speaker 1: I don't know if you can tell. So that's what's 542 00:28:44,400 --> 00:28:46,640 Speaker 1: kind of what's happening to things around a black hole. 543 00:28:46,680 --> 00:28:49,200 Speaker 1: They're getting kind of like stretched a lot by this 544 00:28:49,400 --> 00:28:52,520 Speaker 1: the intense gravitational forces, but they're also it also sort 545 00:28:52,520 --> 00:28:54,760 Speaker 1: of happens not just because of the tidal forces, but 546 00:28:54,880 --> 00:28:57,880 Speaker 1: just because it's going so fast around the black hole, right, 547 00:28:57,920 --> 00:29:00,600 Speaker 1: because things get sucked in pretty fast, pending on how 548 00:29:00,640 --> 00:29:02,640 Speaker 1: fast the black hole is spinning and this stuff around 549 00:29:02,680 --> 00:29:05,440 Speaker 1: it is spinning, absolutely, it can get going pretty fast, 550 00:29:05,720 --> 00:29:09,360 Speaker 1: just like a figure skater speeds up and spins faster 551 00:29:09,440 --> 00:29:12,320 Speaker 1: if she pulls in her arms because of conservation of 552 00:29:12,320 --> 00:29:14,880 Speaker 1: angle momentum, or just the way like comets as they 553 00:29:14,880 --> 00:29:17,720 Speaker 1: approach the Sun from the outer Solar System get going 554 00:29:17,800 --> 00:29:20,920 Speaker 1: really really fast as you fall in towards the center 555 00:29:21,040 --> 00:29:24,000 Speaker 1: of the black hole. Then you go faster and faster 556 00:29:24,240 --> 00:29:27,160 Speaker 1: both in spin and in velocity. So you get a 557 00:29:27,160 --> 00:29:30,080 Speaker 1: lot of particles moving really really fast, bumping into each other. 558 00:29:30,240 --> 00:29:33,880 Speaker 1: And that's what temperature is. Temperature is basically like spedometer 559 00:29:34,000 --> 00:29:37,280 Speaker 1: of particles, right, right, So thanks are crazy spinning around 560 00:29:37,440 --> 00:29:40,040 Speaker 1: a black hole, and so somehow that gives us energy, 561 00:29:40,120 --> 00:29:43,560 Speaker 1: right like things are getting pulled apart, rubbing, exploding, crashing, 562 00:29:43,880 --> 00:29:47,160 Speaker 1: and that just gives us a lot of light and radiation. Yeah, 563 00:29:47,200 --> 00:29:49,440 Speaker 1: like we said before, things that are hot, they glow, 564 00:29:49,840 --> 00:29:52,200 Speaker 1: and so this gas is super duper hot, and so 565 00:29:52,360 --> 00:29:54,800 Speaker 1: it glows in the X ray gives us these very 566 00:29:54,920 --> 00:29:57,960 Speaker 1: very powerful X ray radiation, which is just another kind 567 00:29:57,960 --> 00:30:01,240 Speaker 1: of photon, just much higher fe quency. Yeah, pretty close. 568 00:30:01,280 --> 00:30:02,800 Speaker 1: And so for a long time we thought that these 569 00:30:02,840 --> 00:30:06,680 Speaker 1: glowing black holes were actually stars. Right. In fact, we 570 00:30:06,800 --> 00:30:10,080 Speaker 1: call them quasi stars. Yeah, they've been seen since the 571 00:30:10,160 --> 00:30:13,160 Speaker 1: early parts of last century. In the nineteen fifties, they 572 00:30:13,160 --> 00:30:15,440 Speaker 1: started to study them more intensely, but they didn't really 573 00:30:15,520 --> 00:30:18,880 Speaker 1: understand what they were because they were very very bright, 574 00:30:19,280 --> 00:30:22,200 Speaker 1: but their spectrum was very very weird, Like if you 575 00:30:22,240 --> 00:30:24,400 Speaker 1: look at the frequency of the light that they emitted, 576 00:30:24,560 --> 00:30:28,080 Speaker 1: it didn't match what typical stars emitted. They looked like 577 00:30:28,120 --> 00:30:31,160 Speaker 1: they were a red shifted super duper far like the 578 00:30:31,200 --> 00:30:35,720 Speaker 1: photons were shifted really far down in wavelength compared to 579 00:30:35,760 --> 00:30:38,640 Speaker 1: most stars. And usually when that happens, it means that 580 00:30:38,640 --> 00:30:41,200 Speaker 1: the thing you're looking at is really really far away, 581 00:30:41,640 --> 00:30:43,840 Speaker 1: so it's moving away from you quickly. That's how we 582 00:30:43,920 --> 00:30:46,400 Speaker 1: measured the distance to things sometimes so that we measured 583 00:30:46,400 --> 00:30:48,520 Speaker 1: this red shift. But in this case, these red shifts 584 00:30:48,560 --> 00:30:51,480 Speaker 1: were super dramatic, and yet the objects were really bright, 585 00:30:51,840 --> 00:30:54,080 Speaker 1: and so at first glance it seems like something which 586 00:30:54,120 --> 00:30:57,240 Speaker 1: is really bright and also crazy far away, which means 587 00:30:57,240 --> 00:31:00,640 Speaker 1: it must be like riduculously bright. So first atronomers were 588 00:31:00,640 --> 00:31:03,920 Speaker 1: really scratching their heads wondering what these things were interesting 589 00:31:04,000 --> 00:31:05,880 Speaker 1: like to the naked eye, and when when you look 590 00:31:05,920 --> 00:31:07,480 Speaker 1: up at the night sky, it just looks like a 591 00:31:07,480 --> 00:31:09,680 Speaker 1: little pin bright pin point, But when you look at 592 00:31:09,680 --> 00:31:12,120 Speaker 1: the like the frequency of the light, it actually tells 593 00:31:12,160 --> 00:31:14,560 Speaker 1: you that it's crazy bright and crazy far. Yeah, they 594 00:31:14,600 --> 00:31:17,560 Speaker 1: can be like a hundred times brighter than the other 595 00:31:17,640 --> 00:31:20,760 Speaker 1: galaxies near them. So people like, what's going on? How 596 00:31:20,800 --> 00:31:23,840 Speaker 1: are these things so bright? Because they're already really really 597 00:31:23,880 --> 00:31:26,440 Speaker 1: far away, these things, like just to get a scale, 598 00:31:26,600 --> 00:31:29,040 Speaker 1: you know, these things like at their source would have 599 00:31:29,080 --> 00:31:32,040 Speaker 1: to be like four trillion times brighter than the sun, 600 00:31:32,760 --> 00:31:35,240 Speaker 1: like at the same distance. And so then it turned 601 00:31:35,280 --> 00:31:38,200 Speaker 1: out that those are actually black holes, that the ones 602 00:31:38,240 --> 00:31:40,040 Speaker 1: that we saw in this guy that were so bright 603 00:31:40,120 --> 00:31:43,000 Speaker 1: and so far so people saw these before black holes 604 00:31:43,000 --> 00:31:45,920 Speaker 1: were really taken seriously as an astronomical object, and so 605 00:31:45,960 --> 00:31:47,640 Speaker 1: it took a few decades for people to sort of 606 00:31:47,800 --> 00:31:50,680 Speaker 1: put those two puzzles together. You know, what are these 607 00:31:50,760 --> 00:31:54,520 Speaker 1: quasars and also our black holes? Real people put that together, like, wow, 608 00:31:54,600 --> 00:31:57,440 Speaker 1: black holes. Maybe that's what these things are. Maybe they 609 00:31:57,440 --> 00:32:01,240 Speaker 1: are powering these quasars. And they came all together when 610 00:32:01,240 --> 00:32:04,520 Speaker 1: people started studying like the size of these quasars. One 611 00:32:04,520 --> 00:32:06,800 Speaker 1: thing that's really interesting about them is that quasars are 612 00:32:06,880 --> 00:32:10,160 Speaker 1: highly variable. They don't just like burn brightly all the time. 613 00:32:10,360 --> 00:32:12,760 Speaker 1: That's because the gas around the black hole is really volatile. 614 00:32:13,280 --> 00:32:16,240 Speaker 1: But if the brightness is varying, like over a few days, 615 00:32:16,480 --> 00:32:19,280 Speaker 1: that actually tells you something about the size of the object, 616 00:32:19,480 --> 00:32:21,320 Speaker 1: because it means it can only be like a few 617 00:32:21,480 --> 00:32:25,160 Speaker 1: light days across. It can't be really really large and 618 00:32:25,240 --> 00:32:29,600 Speaker 1: also like coherently varying in time very quickly, and so 619 00:32:29,640 --> 00:32:32,720 Speaker 1: that tells you that it's really small and also really intense. 620 00:32:32,760 --> 00:32:35,760 Speaker 1: It takes a lot of mass to power all that brightness, 621 00:32:36,000 --> 00:32:38,480 Speaker 1: So that's when people start to realize maybe these things 622 00:32:38,520 --> 00:32:41,600 Speaker 1: are powered by black holes. You're saying that if something 623 00:32:41,760 --> 00:32:45,120 Speaker 1: is that bright and if it's large, it wouldn't be 624 00:32:45,600 --> 00:32:47,760 Speaker 1: you know, changing in terms of the light it gives up. 625 00:32:48,320 --> 00:32:50,320 Speaker 1: You can't have two things that are like a light 626 00:32:50,400 --> 00:32:53,720 Speaker 1: year apart, coherently varying in time, like having the same 627 00:32:53,760 --> 00:32:56,080 Speaker 1: pattern over in just a few days, because they have 628 00:32:56,120 --> 00:32:58,040 Speaker 1: to be somehow communicating with each other. But they are 629 00:32:58,160 --> 00:33:00,360 Speaker 1: light year apart, so they can't. So if two things 630 00:33:00,360 --> 00:33:02,920 Speaker 1: are in sync over a period of like a day 631 00:33:03,040 --> 00:33:04,880 Speaker 1: or an hour, then they have to be within a 632 00:33:04,960 --> 00:33:07,160 Speaker 1: light day or a light hour of each other if 633 00:33:07,160 --> 00:33:09,680 Speaker 1: the same process is driving them. So it's like a 634 00:33:09,720 --> 00:33:11,920 Speaker 1: cool indirect way to get a sense of the size 635 00:33:11,920 --> 00:33:16,560 Speaker 1: of an object by seeing how quickly it's light varies. Interesting, 636 00:33:16,600 --> 00:33:19,040 Speaker 1: I guess the speed of light limits even like how 637 00:33:19,520 --> 00:33:22,280 Speaker 1: fast you can coordinate different parts of a bright object. 638 00:33:22,800 --> 00:33:24,200 Speaker 1: It's kind of what you're saying, you know, if they're 639 00:33:24,240 --> 00:33:26,600 Speaker 1: driven by the same fundamental mechanism. They have the same 640 00:33:26,680 --> 00:33:30,160 Speaker 1: underlying cause, like two sides of an object grow brighter 641 00:33:30,280 --> 00:33:33,080 Speaker 1: or darker because of the same underlying physics that's happening 642 00:33:33,120 --> 00:33:35,440 Speaker 1: inside of it. Then they can't be that far apart. 643 00:33:35,760 --> 00:33:38,360 Speaker 1: So you concluded, well, this must be something super bright, 644 00:33:38,400 --> 00:33:42,000 Speaker 1: super far and also super small, or at least, you know, 645 00:33:42,080 --> 00:33:44,680 Speaker 1: at least the size of like the our solar system 646 00:33:44,760 --> 00:33:47,840 Speaker 1: or a sun exactly. And another interesting piece of the 647 00:33:47,880 --> 00:33:51,360 Speaker 1: puzzle is that we mostly see them really far away. Right, 648 00:33:51,400 --> 00:33:54,080 Speaker 1: we said earlier that we see them really high red shifts, 649 00:33:54,080 --> 00:33:56,959 Speaker 1: which means they're mostly far away. And you might wonder, like, well, 650 00:33:57,000 --> 00:33:59,040 Speaker 1: if these things are really bright, shouldn't we see a 651 00:33:59,080 --> 00:34:01,680 Speaker 1: bunch of them close are up that are like obviously 652 00:34:01,720 --> 00:34:04,040 Speaker 1: really really bright. But the thing is that these things 653 00:34:04,040 --> 00:34:07,560 Speaker 1: were made mostly in the early part of the universe's history, 654 00:34:07,960 --> 00:34:10,719 Speaker 1: like around three billion years was the peak time to 655 00:34:10,800 --> 00:34:13,560 Speaker 1: make these quasars, and since then we haven't really been 656 00:34:13,560 --> 00:34:16,360 Speaker 1: making them very much anymore. So most of the quasars 657 00:34:16,360 --> 00:34:18,680 Speaker 1: in the universe are far away from us because the 658 00:34:18,719 --> 00:34:21,799 Speaker 1: ones close by have already died out. They don't last 659 00:34:21,840 --> 00:34:24,560 Speaker 1: that long. They only last like ten or twenty million years. 660 00:34:24,880 --> 00:34:26,799 Speaker 1: I guess what you're saying is that, you know, not 661 00:34:26,920 --> 00:34:30,600 Speaker 1: all black holes have an accretion disc or like stuff 662 00:34:30,840 --> 00:34:33,480 Speaker 1: blowing brightly around them. And so the ones that we 663 00:34:33,640 --> 00:34:36,239 Speaker 1: that do seem to have that we can see are 664 00:34:36,280 --> 00:34:39,440 Speaker 1: probably old because it's probably the black holes are closer 665 00:34:39,520 --> 00:34:42,680 Speaker 1: to us. I've already burrowed out their accretion disk. Yes, 666 00:34:42,680 --> 00:34:45,319 Speaker 1: And it's not something that we understand very well because 667 00:34:45,320 --> 00:34:47,680 Speaker 1: we'll talk about a bit more later, like what's going 668 00:34:47,719 --> 00:34:50,400 Speaker 1: on very close to the black hole, how they gather 669 00:34:50,560 --> 00:34:52,920 Speaker 1: gas and how they blow that gas away due to 670 00:34:52,960 --> 00:34:56,840 Speaker 1: the intense radiation is not something that's currently very well understood. 671 00:34:57,000 --> 00:35:00,160 Speaker 1: We think that about five to ten of galaxies with 672 00:35:00,239 --> 00:35:03,520 Speaker 1: black holes at their core have quaisars. So a lot 673 00:35:03,560 --> 00:35:06,160 Speaker 1: of the galaxies around us that have black holes don't 674 00:35:06,280 --> 00:35:09,320 Speaker 1: have a quasar. Its requires like sort of special conditions. 675 00:35:09,360 --> 00:35:11,759 Speaker 1: Not every single one does it right, or maybe they did, 676 00:35:11,880 --> 00:35:14,680 Speaker 1: but they it's no longer kind of burning bright. Yeah, 677 00:35:14,800 --> 00:35:16,960 Speaker 1: if they grew to a certain size and they've blown 678 00:35:17,000 --> 00:35:19,440 Speaker 1: away a lot of the gas that they would otherwise feed. 679 00:35:19,719 --> 00:35:22,480 Speaker 1: Remember we had another episode about how you could quickly 680 00:35:22,520 --> 00:35:24,600 Speaker 1: make a black hole, and it's not actually that easy 681 00:35:24,800 --> 00:35:26,799 Speaker 1: to just like dump a lot of stuff into a 682 00:35:26,880 --> 00:35:30,840 Speaker 1: black hole, because as they grow, their gravity gets stronger 683 00:35:31,000 --> 00:35:34,120 Speaker 1: and they create this intense radiation which actually works against 684 00:35:34,120 --> 00:35:37,799 Speaker 1: them because it blows away a lot of the stuff nearby. Interesting, 685 00:35:38,560 --> 00:35:41,160 Speaker 1: it's like it it gets indigestion, you get you get 686 00:35:41,200 --> 00:35:44,439 Speaker 1: a feed it slowly. You gotta burp your black hole 687 00:35:44,520 --> 00:35:47,560 Speaker 1: just right, yea, otherwise still burp other things out. So 688 00:35:47,600 --> 00:35:50,759 Speaker 1: then that's kind of so we don't see quasars near us, 689 00:35:51,280 --> 00:35:54,600 Speaker 1: meaning black holes that blow brightly, but they are out there, 690 00:35:54,880 --> 00:35:56,920 Speaker 1: and they do it through this kind of mechanism of 691 00:35:56,960 --> 00:36:00,720 Speaker 1: the acreation, this burning stuff up, crashing it around itself. 692 00:36:00,760 --> 00:36:03,920 Speaker 1: And also sometimes that radiation can be very focused, right, 693 00:36:03,920 --> 00:36:07,080 Speaker 1: in which case we get super extra bright quasars. Yeah, 694 00:36:07,080 --> 00:36:09,920 Speaker 1: if quasars happen to be pointed right at us or 695 00:36:09,960 --> 00:36:12,560 Speaker 1: they're moving towards us, that we call them blaze ours 696 00:36:13,040 --> 00:36:16,839 Speaker 1: because their radiation gets boosted by being pointed right at us. Right. 697 00:36:16,840 --> 00:36:18,840 Speaker 1: But I guess this is a kind of a subtle 698 00:36:18,880 --> 00:36:21,800 Speaker 1: point is that sometimes in a black hole, the ecreation 699 00:36:21,840 --> 00:36:23,920 Speaker 1: disc is glowing. It's bright, we can see it from 700 00:36:23,920 --> 00:36:26,520 Speaker 1: far away. And sometimes but sometimes it's sort of aligned 701 00:36:26,520 --> 00:36:28,960 Speaker 1: in the right way where it's super extra bright. Right, Yeah, 702 00:36:29,000 --> 00:36:31,520 Speaker 1: if it's lined up directly to Earth, like the most 703 00:36:31,520 --> 00:36:34,719 Speaker 1: intense part of the quasar mission is pointing right at 704 00:36:34,760 --> 00:36:38,080 Speaker 1: the Earth, then they get super extra bright. Does that 705 00:36:38,120 --> 00:36:42,799 Speaker 1: mean that all quasars are all glowing? Accretion discs are directional, 706 00:36:42,880 --> 00:36:45,040 Speaker 1: like they all sort of point in a particular way 707 00:36:45,080 --> 00:36:47,600 Speaker 1: like a flashlight. They do, but not that intensely. They're 708 00:36:47,600 --> 00:36:50,360 Speaker 1: not like extremely focused the way like a pulsar is 709 00:36:50,680 --> 00:36:53,000 Speaker 1: a pulsar, you just won't even see that radiation if 710 00:36:53,040 --> 00:36:56,640 Speaker 1: it's not pointed at the Earth. These are not as directional. 711 00:36:56,960 --> 00:36:58,920 Speaker 1: But if the intense part of it is pointed at 712 00:36:58,920 --> 00:37:01,600 Speaker 1: the Earth, then yeah, there's an enhancement factor there. But 713 00:37:01,680 --> 00:37:04,439 Speaker 1: black holes do have another way that they glow, which 714 00:37:04,640 --> 00:37:07,680 Speaker 1: is very pointed. Oh yeah, what is that? Well, on 715 00:37:07,800 --> 00:37:10,839 Speaker 1: top of the accretion disc, they also sometimes create these 716 00:37:10,880 --> 00:37:14,960 Speaker 1: incredible jets of matter which fly out from the poles 717 00:37:15,000 --> 00:37:17,960 Speaker 1: of the black hole, both sort of north and south, 718 00:37:18,160 --> 00:37:20,960 Speaker 1: and these things are really extraordinary. So some black holes 719 00:37:20,960 --> 00:37:24,000 Speaker 1: don't have an increation disc, some of them do. It's glowing, 720 00:37:24,080 --> 00:37:26,680 Speaker 1: it's glowing in a sort of general direction, and some 721 00:37:26,760 --> 00:37:28,960 Speaker 1: of them are even more focused what you're saying, like, 722 00:37:29,000 --> 00:37:32,759 Speaker 1: somehow this accretion disk gathers things and shoots it in 723 00:37:32,760 --> 00:37:35,279 Speaker 1: one way, sort of like a like a tornado. Sort 724 00:37:35,280 --> 00:37:38,000 Speaker 1: of like a tornado. Some of these black holes have 725 00:37:38,120 --> 00:37:41,920 Speaker 1: these incredible things we call jets, which shoot out photons 726 00:37:41,920 --> 00:37:45,480 Speaker 1: and other kinds of matter, really really long jets, like 727 00:37:45,719 --> 00:37:48,880 Speaker 1: much larger than the black hole itself. For example, some 728 00:37:48,920 --> 00:37:51,840 Speaker 1: of these jets are like five thousand to a hundred 729 00:37:51,880 --> 00:37:55,319 Speaker 1: thousand light years long. Whoa, and so what do they 730 00:37:55,320 --> 00:37:57,520 Speaker 1: look like? They sort of look like a spotlight shining 731 00:37:57,520 --> 00:37:59,920 Speaker 1: out into the night skuy kind of, yeah, you can 732 00:38:00,040 --> 00:38:01,759 Speaker 1: you like a little dot from the quas are at 733 00:38:01,760 --> 00:38:05,320 Speaker 1: the core, and then you see these incredibly long rays 734 00:38:05,640 --> 00:38:08,880 Speaker 1: which shoot out into the interstellar medium. And because that 735 00:38:08,960 --> 00:38:11,720 Speaker 1: then hit stuff like gas and dust, they can create 736 00:38:11,800 --> 00:38:14,520 Speaker 1: these big shock waves. And so you can google a 737 00:38:14,520 --> 00:38:17,319 Speaker 1: picture of like astrophysical jets. But they look like these 738 00:38:17,360 --> 00:38:21,600 Speaker 1: incredible fireballs shooting out both sides of the black hole, 739 00:38:21,880 --> 00:38:24,879 Speaker 1: and they're much much bigger than the actual extent of 740 00:38:24,920 --> 00:38:27,960 Speaker 1: the black hole. One astronomer described as like seeing the 741 00:38:28,000 --> 00:38:32,799 Speaker 1: statue of Liberty popping out of a marble. Decide to 742 00:38:32,840 --> 00:38:35,440 Speaker 1: see but you're saying, we don't really understand how these 743 00:38:35,520 --> 00:38:38,440 Speaker 1: jets are formed, right, Like I imagine they're creating. This 744 00:38:38,560 --> 00:38:40,879 Speaker 1: is stuff kind of orbiting around the black hole, waiting 745 00:38:40,920 --> 00:38:42,880 Speaker 1: to fall into the black hole. So how does stuff 746 00:38:42,920 --> 00:38:45,600 Speaker 1: actually kind of pop out. It's all connected into this 747 00:38:45,680 --> 00:38:47,920 Speaker 1: question of how stuff falls into the black hole and 748 00:38:48,000 --> 00:38:50,080 Speaker 1: what happens. But we think that a lot of black 749 00:38:50,080 --> 00:38:53,359 Speaker 1: holes are not just curved regions of space time. They're 750 00:38:53,360 --> 00:38:57,480 Speaker 1: also spinning, and also they probably have electric charge, and 751 00:38:57,520 --> 00:38:59,640 Speaker 1: those are the three things that black holes can have 752 00:39:00,040 --> 00:39:03,080 Speaker 1: ass spin, and charge. And if a black hole has 753 00:39:03,080 --> 00:39:06,040 Speaker 1: electric charge and it's spinning, then it also has a 754 00:39:06,120 --> 00:39:09,600 Speaker 1: very very powerful magnetic field, and that magnetic field will 755 00:39:09,640 --> 00:39:11,960 Speaker 1: direct the path of particles just the same way that 756 00:39:12,040 --> 00:39:15,799 Speaker 1: the Earth's magnetic field changes how the solar wind hits 757 00:39:15,800 --> 00:39:18,800 Speaker 1: the Earth. Most of those particles don't end up coming 758 00:39:18,840 --> 00:39:22,439 Speaker 1: down and hitting us. They spiral around magnetic field lines 759 00:39:22,480 --> 00:39:24,400 Speaker 1: and go to the north pole or the south pole, 760 00:39:24,640 --> 00:39:27,200 Speaker 1: and that's what the northern lights are. In the same way, 761 00:39:27,400 --> 00:39:30,319 Speaker 1: this incredibly intense magnetic field of a black hole, some 762 00:39:30,440 --> 00:39:32,880 Speaker 1: of these particles, which otherwise might have fallen into the 763 00:39:32,880 --> 00:39:35,520 Speaker 1: black hole gets sort of like funneled up and shot 764 00:39:35,520 --> 00:39:38,920 Speaker 1: out the top or the bottom of the black hole. Interesting, 765 00:39:39,040 --> 00:39:41,759 Speaker 1: it's sort of channeled by this magnetic field. But I 766 00:39:41,760 --> 00:39:43,359 Speaker 1: guess the question is how does a black hole get 767 00:39:43,360 --> 00:39:46,560 Speaker 1: a charge? Like, does it because it absorbs more electrons 768 00:39:46,600 --> 00:39:50,080 Speaker 1: than than positive charges? Or how does it get a charge? Yeah, 769 00:39:50,160 --> 00:39:52,759 Speaker 1: we think that charge is conserved in the universe. And 770 00:39:52,800 --> 00:39:54,960 Speaker 1: so if you have a black hole that's neutral and 771 00:39:55,040 --> 00:39:57,799 Speaker 1: you toss an electron into it, that black hole now 772 00:39:57,920 --> 00:40:00,239 Speaker 1: has a charge, and you can't like tell where the 773 00:40:00,239 --> 00:40:03,279 Speaker 1: electron is inside the event horizon. All you can tell 774 00:40:03,320 --> 00:40:05,960 Speaker 1: is that the black hole itself is now charged. And 775 00:40:06,000 --> 00:40:09,320 Speaker 1: so any black hole which eats more positive than negative 776 00:40:09,360 --> 00:40:11,520 Speaker 1: particles will have a positive charge. And the same is 777 00:40:11,520 --> 00:40:14,279 Speaker 1: true for the opposite scenario. So somehow the black hole 778 00:40:14,440 --> 00:40:17,920 Speaker 1: ate more electrons then and then then post trons, And 779 00:40:18,000 --> 00:40:20,480 Speaker 1: we do have an asymmetry in our universe right. There 780 00:40:20,520 --> 00:40:23,239 Speaker 1: are a lot more electrons out there than positrons, and 781 00:40:23,600 --> 00:40:27,480 Speaker 1: stars and other matter have more electrons in them than positrons, 782 00:40:27,719 --> 00:40:29,879 Speaker 1: while they are also protons in there to balance things out. 783 00:40:30,080 --> 00:40:33,480 Speaker 1: The matter antimatter asymmetry the universe means that there are 784 00:40:33,560 --> 00:40:35,959 Speaker 1: lots of these charge particles sloating around for black holes 785 00:40:35,960 --> 00:40:38,680 Speaker 1: to gobble up. Interesting, that's true for the whole universe. 786 00:40:38,719 --> 00:40:41,120 Speaker 1: You're saying the whole universe has a negative charge. Well, 787 00:40:41,160 --> 00:40:43,319 Speaker 1: that's a really fun question. What is the charge of 788 00:40:43,360 --> 00:40:46,880 Speaker 1: the whole Is it positive, is it negative? Is it 789 00:40:46,920 --> 00:40:50,080 Speaker 1: an optimist, is it a pessimist. That's a really cool question. 790 00:40:50,120 --> 00:40:53,040 Speaker 1: I think that if charge has always been conserved, then 791 00:40:53,040 --> 00:40:56,399 Speaker 1: the universe must have the same charge it had early on, 792 00:40:56,960 --> 00:40:59,000 Speaker 1: And so if it came from like an in phloton 793 00:40:59,120 --> 00:41:01,680 Speaker 1: field or something that we've discussed recently, it probably has 794 00:41:01,719 --> 00:41:05,200 Speaker 1: an overall zero charge. But in the end those charges 795 00:41:05,239 --> 00:41:08,759 Speaker 1: break up into electrons and protons and other kinds of particles, 796 00:41:08,800 --> 00:41:10,960 Speaker 1: some of which might be more likely to be eaten 797 00:41:11,000 --> 00:41:13,239 Speaker 1: and by black holes. But they're also just there are 798 00:41:13,239 --> 00:41:16,279 Speaker 1: patches throughout the universe is not completely smooth, and so 799 00:41:16,320 --> 00:41:18,880 Speaker 1: in the same way that like black holes spin because 800 00:41:18,920 --> 00:41:21,920 Speaker 1: there's angular momentum. Even if the total spin of the 801 00:41:22,000 --> 00:41:24,239 Speaker 1: universe is zero, there are patches of it that's spin 802 00:41:24,360 --> 00:41:26,480 Speaker 1: left or spin right. In the same way there are 803 00:41:26,520 --> 00:41:29,080 Speaker 1: patches of the universe that have more matter or less matter. 804 00:41:29,360 --> 00:41:31,200 Speaker 1: There probably are patches of the universe that have like 805 00:41:31,280 --> 00:41:34,279 Speaker 1: more positive charge and more negative charge, and so black 806 00:41:34,320 --> 00:41:37,640 Speaker 1: holes end up accumulating some charge. Like the chances of 807 00:41:37,680 --> 00:41:41,040 Speaker 1: getting exactly zero charge if you have you know, ten 808 00:41:41,160 --> 00:41:44,560 Speaker 1: to the fifty particles is like the chances of flipping 809 00:41:44,600 --> 00:41:49,400 Speaker 1: a coin tend to the fifty times and getting exactly heads. 810 00:41:49,440 --> 00:41:52,080 Speaker 1: It's very unlikely. Yeah, it seems like it. So you're 811 00:41:52,120 --> 00:41:54,400 Speaker 1: if you're a black hole, you could be team positive 812 00:41:54,480 --> 00:41:58,480 Speaker 1: or team negative. There's two teams exactly probably very few 813 00:41:58,480 --> 00:42:02,000 Speaker 1: black holes like exactly on that knife's edge, and as 814 00:42:02,000 --> 00:42:04,759 Speaker 1: a result, they get very strong magnetic fields, right, and 815 00:42:04,800 --> 00:42:07,200 Speaker 1: so that's kind of the most intense way that a 816 00:42:07,239 --> 00:42:10,319 Speaker 1: black hole can glow, although it's technically not glowing. It's 817 00:42:10,400 --> 00:42:14,600 Speaker 1: just kind of redirecting and swirling and igniting the stuff 818 00:42:14,600 --> 00:42:17,759 Speaker 1: around it and then shooting it in one particular direction. Yeah, 819 00:42:17,880 --> 00:42:21,399 Speaker 1: and so these astrophysical jets are super fascinating and really 820 00:42:21,400 --> 00:42:24,000 Speaker 1: a source of research right now. People trying to use 821 00:42:24,040 --> 00:42:26,960 Speaker 1: them to understand what happens to a particle as it 822 00:42:27,000 --> 00:42:30,560 Speaker 1: falls into a spinning, electrically charged black hole, whether it 823 00:42:30,560 --> 00:42:33,160 Speaker 1: gets repelled by the magnetic field of the black hole, 824 00:42:33,440 --> 00:42:35,279 Speaker 1: or whether it gets sucked in all this kind of 825 00:42:35,320 --> 00:42:38,480 Speaker 1: stuff that must be pretty cool to think about and model. 826 00:42:38,680 --> 00:42:41,040 Speaker 1: All right, well, let's get into what happens if you 827 00:42:41,160 --> 00:42:43,600 Speaker 1: focus one of these jets on Earth. Is it good 828 00:42:43,640 --> 00:42:46,879 Speaker 1: news or bad news? And let's talk about our most 829 00:42:46,920 --> 00:42:49,520 Speaker 1: recent pictures of black holes. But first let's take another 830 00:42:49,600 --> 00:43:04,360 Speaker 1: quick break. All right, we're talking about glowing black holes, 831 00:43:04,400 --> 00:43:06,320 Speaker 1: and this is, I guess a pretty glowing reveal of 832 00:43:06,360 --> 00:43:09,520 Speaker 1: black holes. Would you say that we can black holes 833 00:43:09,560 --> 00:43:13,840 Speaker 1: five stars absolutely, or a million stars sometimes the trillion stars, 834 00:43:13,880 --> 00:43:16,560 Speaker 1: who knows. So sometimes they admit these intense jets, and 835 00:43:16,600 --> 00:43:18,560 Speaker 1: that's when they really shine in the sky, but they 836 00:43:18,560 --> 00:43:20,759 Speaker 1: can be sort of dangerous, right, like if black hole 837 00:43:20,840 --> 00:43:24,040 Speaker 1: suddenly focus its jet on us, we it might fry 838 00:43:24,080 --> 00:43:27,080 Speaker 1: us kind of right. Yes, these are very intense sources 839 00:43:27,080 --> 00:43:30,000 Speaker 1: of radiation. Fortunately none of them are shined at Earth 840 00:43:30,160 --> 00:43:33,239 Speaker 1: right now because they go really, really far. And the 841 00:43:33,280 --> 00:43:35,640 Speaker 1: black hole is the center of our galaxy, which is 842 00:43:35,680 --> 00:43:38,840 Speaker 1: like one that might be capable of creating very intense radiation. 843 00:43:39,080 --> 00:43:41,480 Speaker 1: We don't think that it has any of these jets. 844 00:43:41,920 --> 00:43:44,200 Speaker 1: It might have very small ones, but we're not sure. 845 00:43:44,200 --> 00:43:46,400 Speaker 1: We're going to try to take a picture of it soon. Well, 846 00:43:46,440 --> 00:43:48,239 Speaker 1: it's sort of sad that black holes are getting their 847 00:43:48,320 --> 00:43:51,640 Speaker 1: jet packs before humans are. But we we do have 848 00:43:51,680 --> 00:43:54,759 Speaker 1: sort of photos of black holes glowing like it's not 849 00:43:54,840 --> 00:43:57,600 Speaker 1: just something that we're posting or wondering about. We do 850 00:43:57,680 --> 00:44:01,400 Speaker 1: have a more recent pictures black holes, right, and you 851 00:44:01,400 --> 00:44:04,279 Speaker 1: can see them going. Yeah. Several years ago, they tied 852 00:44:04,320 --> 00:44:07,600 Speaker 1: together a bunch of radio telescopes around the world into 853 00:44:07,680 --> 00:44:11,560 Speaker 1: sort of like a huge meta telescope, and by taking 854 00:44:11,640 --> 00:44:15,439 Speaker 1: data together for about ten days, different parts of the Earth, 855 00:44:15,480 --> 00:44:17,759 Speaker 1: all working together, all pointed at the same black hole, 856 00:44:17,920 --> 00:44:20,360 Speaker 1: they were able to sort of tie those together into 857 00:44:20,360 --> 00:44:23,680 Speaker 1: a radio telescope effectively the size of the Earth. This 858 00:44:23,719 --> 00:44:27,160 Speaker 1: is called the event Horizon telescope. And they took data 859 00:44:27,160 --> 00:44:29,239 Speaker 1: for about ten days and then crunched it with their 860 00:44:29,280 --> 00:44:33,040 Speaker 1: computers for like two years. And in April two thousand nineteen, 861 00:44:33,280 --> 00:44:35,920 Speaker 1: they put out what was called the first direct image 862 00:44:36,000 --> 00:44:37,719 Speaker 1: of a black hole. And you might remember it. It It 863 00:44:37,800 --> 00:44:40,480 Speaker 1: looks sort of like a glowing donut. Yeah, So you 864 00:44:40,520 --> 00:44:42,920 Speaker 1: can google this and and image and do an image 865 00:44:42,960 --> 00:44:45,320 Speaker 1: starch where I guess what would you start for black 866 00:44:45,360 --> 00:44:48,799 Speaker 1: hole photo? Yeah, black hole photo. Absolutely, that pops right 867 00:44:48,880 --> 00:44:50,440 Speaker 1: up and so you can see you can see sort 868 00:44:50,480 --> 00:44:52,680 Speaker 1: of the dark circle in the middle of the glowing disk, 869 00:44:52,880 --> 00:44:55,080 Speaker 1: and it's sort of skewed though, right, It's it's not 870 00:44:55,200 --> 00:44:57,719 Speaker 1: like a perfectly round donut. It's sort of skewed one 871 00:44:57,800 --> 00:44:59,919 Speaker 1: in one direction. Yeah, it's like a crispy cream you're 872 00:45:00,080 --> 00:45:02,200 Speaker 1: of angling in at as you're about to take your 873 00:45:02,200 --> 00:45:06,680 Speaker 1: first bite, got kind of squished on one side. And 874 00:45:06,719 --> 00:45:08,840 Speaker 1: once you're looking at their the glow, of course, is 875 00:45:08,840 --> 00:45:12,080 Speaker 1: not from the actual black hole. You're not seeing hawking radiation. 876 00:45:12,239 --> 00:45:15,080 Speaker 1: You're seeing the glow of the accretion disk. And that 877 00:45:15,120 --> 00:45:17,960 Speaker 1: black hole is M eight seven. It's at the center 878 00:45:17,960 --> 00:45:21,839 Speaker 1: of a galaxy that's about fifty five million light years away, 879 00:45:21,880 --> 00:45:24,879 Speaker 1: but they chose it because it's incredibly powerful black hole. 880 00:45:25,239 --> 00:45:29,640 Speaker 1: There's like six point five billion solar masses inside of it. Wow, 881 00:45:29,920 --> 00:45:33,239 Speaker 1: six point five billion times the mass of our Sun. 882 00:45:33,440 --> 00:45:36,640 Speaker 1: And it's a fairly close enough for us to sort 883 00:45:36,680 --> 00:45:38,680 Speaker 1: of look at it. And so we have a picture 884 00:45:38,719 --> 00:45:41,840 Speaker 1: of its accretion disk, and there's sort of different theories 885 00:45:41,840 --> 00:45:43,640 Speaker 1: about what's going on there, that's right, And so the 886 00:45:43,640 --> 00:45:46,320 Speaker 1: first picture just sort of like give us the first glance, 887 00:45:46,560 --> 00:45:48,520 Speaker 1: and we saw the accretion disk, we saw the glow. 888 00:45:48,560 --> 00:45:50,759 Speaker 1: We confirmed what we thought you see the hole in 889 00:45:50,760 --> 00:45:52,840 Speaker 1: the center of it, which is the event horizon, and 890 00:45:52,880 --> 00:45:54,920 Speaker 1: that's about as big as we expected it to be. 891 00:45:55,239 --> 00:45:57,920 Speaker 1: It's really incredibly huge though, Like that event horizon is 892 00:45:58,040 --> 00:46:01,799 Speaker 1: larger than the radius of Pluto. Like that black hole 893 00:46:01,880 --> 00:46:05,040 Speaker 1: is a monster wow, meaning like you could sit in 894 00:46:05,040 --> 00:46:07,359 Speaker 1: inside of our solar system and it would basically take 895 00:46:07,600 --> 00:46:09,359 Speaker 1: take over the whole solar system. It would take over 896 00:46:09,400 --> 00:46:13,040 Speaker 1: the whole solar system exactly. And recently what they've done 897 00:46:13,120 --> 00:46:16,040 Speaker 1: is they've studied that data in more detail. They went 898 00:46:16,080 --> 00:46:18,319 Speaker 1: back and they reanalyze the data trying to get more 899 00:46:18,400 --> 00:46:23,279 Speaker 1: information about what's swirling around inside that acretion disk. Because 900 00:46:23,320 --> 00:46:24,799 Speaker 1: what they did at first, we just sort of like 901 00:46:25,040 --> 00:46:27,279 Speaker 1: look at the photons and gather them and say where 902 00:46:27,320 --> 00:46:29,400 Speaker 1: is it bright, where is it not that bright? And 903 00:46:29,440 --> 00:46:31,640 Speaker 1: that's the picture that you see is like an intensity 904 00:46:31,680 --> 00:46:34,399 Speaker 1: map essentially shows you where it's glowing hot and where 905 00:46:34,400 --> 00:46:36,640 Speaker 1: it's not glowing as much. What they did now is 906 00:46:36,640 --> 00:46:38,800 Speaker 1: they went back and they analyzed it to see how 907 00:46:38,840 --> 00:46:42,759 Speaker 1: those photons are polarized. Like photons when they move through 908 00:46:42,800 --> 00:46:45,440 Speaker 1: space can do so in various ways, like we sometimes 909 00:46:45,440 --> 00:46:48,759 Speaker 1: talk about how electrons have spin, spin up or spin down. 910 00:46:48,960 --> 00:46:51,440 Speaker 1: Photons also have spin, so they don't just fly through 911 00:46:51,480 --> 00:46:54,160 Speaker 1: space with energy. They can also spin in various ways 912 00:46:54,320 --> 00:46:57,399 Speaker 1: you might be familiar with, like sunglasses that filter out 913 00:46:57,440 --> 00:47:00,560 Speaker 1: polarized light, for example, and so like comes in sort 914 00:47:00,560 --> 00:47:02,880 Speaker 1: of different spins. And what they did is they looked 915 00:47:02,880 --> 00:47:06,280 Speaker 1: at the photons and counted how many spin in different ways, 916 00:47:06,520 --> 00:47:09,719 Speaker 1: because this tells you something really interesting about the magnetic 917 00:47:09,800 --> 00:47:13,960 Speaker 1: field inside that accretion disk, which affects how photons spin. 918 00:47:14,920 --> 00:47:17,960 Speaker 1: It's like you're you're looking at for extra information in 919 00:47:18,000 --> 00:47:19,920 Speaker 1: the light that they might tell you what's going on, 920 00:47:19,960 --> 00:47:22,560 Speaker 1: because we we don't understand it right exactly. It's like 921 00:47:22,600 --> 00:47:24,440 Speaker 1: you first had a black and white picture, and now 922 00:47:24,480 --> 00:47:26,719 Speaker 1: you're looking at the different colors, right, You're looking for 923 00:47:27,000 --> 00:47:30,080 Speaker 1: extra information, new dimensions to this. So they crunched the 924 00:47:30,160 --> 00:47:33,200 Speaker 1: same picture, the same data through their computers for another 925 00:47:33,280 --> 00:47:36,560 Speaker 1: two years, and now they have an updated photograph. And 926 00:47:36,560 --> 00:47:39,759 Speaker 1: this one looks quite different because it's still the acreation disc. 927 00:47:39,920 --> 00:47:42,120 Speaker 1: But you can see these stripes. You can see these 928 00:47:42,160 --> 00:47:45,600 Speaker 1: like twists, this spiral pattern that tells you sort of 929 00:47:45,600 --> 00:47:48,440 Speaker 1: where the magnetic field is in the accretion disk and 930 00:47:48,480 --> 00:47:51,919 Speaker 1: sort of what its intensity. Is interesting, like the whole 931 00:47:52,000 --> 00:47:55,279 Speaker 1: disc has a magnetic field or there's like variations in 932 00:47:55,280 --> 00:47:58,359 Speaker 1: the field all around their variations in the field, and 933 00:47:58,440 --> 00:48:01,080 Speaker 1: from the pattern of where the hootons are and how 934 00:48:01,120 --> 00:48:03,279 Speaker 1: they are polarized, you can get a sense for the 935 00:48:03,320 --> 00:48:05,960 Speaker 1: strength of the magnetic field and like how those magnetic 936 00:48:05,960 --> 00:48:08,640 Speaker 1: field lines look, which tells you a lot about how 937 00:48:08,680 --> 00:48:11,640 Speaker 1: things must be moving inside the accretion disk, because those 938 00:48:11,719 --> 00:48:14,640 Speaker 1: very intensive magnetic fields are sort of like funneling particles. 939 00:48:14,680 --> 00:48:18,719 Speaker 1: They're telling particles where they can and can't go. Interesting, 940 00:48:18,760 --> 00:48:21,440 Speaker 1: like you're looking at the texture of the accretion disk. Yeah, 941 00:48:21,520 --> 00:48:23,640 Speaker 1: and so there are two theories about what's going on there, 942 00:48:23,719 --> 00:48:27,239 Speaker 1: and they have pretty fun acronyms matt and sane. It's 943 00:48:27,239 --> 00:48:30,919 Speaker 1: either crazy black hole or or a reasonable black hole. 944 00:48:31,040 --> 00:48:34,319 Speaker 1: Reasonable black Yeah. People were wondering how this works, and 945 00:48:34,360 --> 00:48:37,520 Speaker 1: they developed these different models for how things in the 946 00:48:37,560 --> 00:48:39,960 Speaker 1: acretion disk gets sort of slurped up by the magnetic 947 00:48:40,000 --> 00:48:43,440 Speaker 1: fields and then shot into this helix which pushes them 948 00:48:43,440 --> 00:48:46,799 Speaker 1: out into this astrophysical jet. Like how do particles when 949 00:48:46,800 --> 00:48:48,480 Speaker 1: they fall in through the accretion disk, how do they 950 00:48:48,520 --> 00:48:50,839 Speaker 1: sort of miss falling into the black hole and end 951 00:48:50,920 --> 00:48:54,520 Speaker 1: up pumped out into this incredibly long death ray through space. 952 00:48:54,719 --> 00:48:57,239 Speaker 1: So first people thought like, mostly it's just sort of 953 00:48:57,320 --> 00:49:02,080 Speaker 1: crazy and turbulent that you don't have really intense magnetic fields, 954 00:49:02,120 --> 00:49:04,279 Speaker 1: but that stuff just sort of like falls into the 955 00:49:04,280 --> 00:49:07,440 Speaker 1: center and the accretion disc sort of controls the helix. 956 00:49:07,480 --> 00:49:10,480 Speaker 1: That it's an angular momentum is sort of what's driving 957 00:49:10,520 --> 00:49:12,759 Speaker 1: the spinning of everything, and that the helix sort of 958 00:49:12,840 --> 00:49:16,200 Speaker 1: forms eventually from that spin. That was the model they 959 00:49:16,239 --> 00:49:20,520 Speaker 1: call sane stable and normal evolution s a n E. 960 00:49:20,960 --> 00:49:23,839 Speaker 1: And then there was a competing model they call MAD 961 00:49:23,880 --> 00:49:27,520 Speaker 1: for magnetically arrested disk. This is a model for what 962 00:49:27,600 --> 00:49:30,880 Speaker 1: happens if you like really crank up the magnetic fields, 963 00:49:30,920 --> 00:49:34,799 Speaker 1: like really strong, powerful magnetic fields, so that they're sort 964 00:49:34,800 --> 00:49:37,279 Speaker 1: of in control. And what happens there is that you 965 00:49:37,320 --> 00:49:41,280 Speaker 1: expect like coherent channels of particles. You expect like tubes 966 00:49:41,400 --> 00:49:45,240 Speaker 1: of particles being funneled by this magnetic field really quickly 967 00:49:45,280 --> 00:49:48,439 Speaker 1: wrapping up into a very powerful helix. And it also 968 00:49:48,520 --> 00:49:53,080 Speaker 1: predicts more polarized light because of these strong magnetic fields. Interesting, 969 00:49:53,120 --> 00:49:55,400 Speaker 1: it's like we know that there's an acreation disk, but 970 00:49:55,440 --> 00:49:58,600 Speaker 1: we don't know what's kind of dominating the way it works. 971 00:49:58,640 --> 00:50:01,560 Speaker 1: It's gravity, is it magnetic fields? And it sounds like 972 00:50:01,600 --> 00:50:03,919 Speaker 1: it's mostly magnetic fields or or at least they play 973 00:50:03,960 --> 00:50:06,319 Speaker 1: a huge part that we didn't think about before. Yeah, 974 00:50:06,360 --> 00:50:09,360 Speaker 1: and so this updated picture that shows us the polarization 975 00:50:09,360 --> 00:50:11,879 Speaker 1: of the photons, it helps us determine which of these 976 00:50:11,920 --> 00:50:15,080 Speaker 1: two models is accurate. And so the data supports that 977 00:50:15,280 --> 00:50:18,239 Speaker 1: black holes are mad rather than sane, that they have 978 00:50:18,400 --> 00:50:22,520 Speaker 1: really intense magnetic fields, and that that's what's creating this helix, 979 00:50:22,520 --> 00:50:24,520 Speaker 1: and that's what pulling the particles out of the increation 980 00:50:24,520 --> 00:50:27,280 Speaker 1: disk and then into this jet that reaches out through space. 981 00:50:27,960 --> 00:50:30,359 Speaker 1: But what do you think make the mad of not 982 00:50:30,440 --> 00:50:37,080 Speaker 1: getting enough attention? It's because they got overcharged. Nice, they 983 00:50:37,160 --> 00:50:41,360 Speaker 1: stop being positive. Exactly. You eat too many electrons and 984 00:50:41,400 --> 00:50:43,120 Speaker 1: you end up feeling kind of negative. Yeah, they had 985 00:50:43,120 --> 00:50:46,680 Speaker 1: a negative experience, for sure. Now they're mad. They lost 986 00:50:46,680 --> 00:50:50,080 Speaker 1: their sanity. There you go, exactly. And so it's it's 987 00:50:50,120 --> 00:50:52,640 Speaker 1: cool because it's the first time we've really seen something 988 00:50:52,640 --> 00:50:55,439 Speaker 1: about the dynamics of the increation disk. Before we saw 989 00:50:55,480 --> 00:50:57,560 Speaker 1: sort of like a static image like Okay, it's there, 990 00:50:57,600 --> 00:50:59,920 Speaker 1: it's a blob, we know the shape. That's cool. Now 991 00:51:00,040 --> 00:51:02,319 Speaker 1: we're seeing sort of like how it's moving with the 992 00:51:02,440 --> 00:51:04,960 Speaker 1: energy flow is inside of it, which really helps us 993 00:51:04,960 --> 00:51:07,200 Speaker 1: build a picture for how the matter is flowing in 994 00:51:07,280 --> 00:51:10,080 Speaker 1: and how it's getting ejected. Yeah, pretty cool. And I 995 00:51:10,080 --> 00:51:12,239 Speaker 1: guess what's interesting is that we are getting these sort 996 00:51:12,239 --> 00:51:15,760 Speaker 1: of you know, more accurate, more interesting pictures about what's 997 00:51:15,800 --> 00:51:18,000 Speaker 1: going on outside of a black hole, Like we're getting 998 00:51:18,000 --> 00:51:20,600 Speaker 1: closer and closer to the actual black hole itself and 999 00:51:20,680 --> 00:51:23,399 Speaker 1: kind of maybe looking at what's going on in it. Yeah, 1000 00:51:23,440 --> 00:51:26,240 Speaker 1: we'll be pushing up harder and harder against that envelope 1001 00:51:26,239 --> 00:51:28,799 Speaker 1: of the event horizon. The more information we can gather 1002 00:51:28,840 --> 00:51:31,440 Speaker 1: about what happens very close to the black hole, the 1003 00:51:31,480 --> 00:51:33,560 Speaker 1: more it helps us refine our models for what's going 1004 00:51:33,600 --> 00:51:36,319 Speaker 1: on inside the black hole. People talk a lot about 1005 00:51:36,400 --> 00:51:39,719 Speaker 1: science being testable and falsifiable, right, but even if we 1006 00:51:39,760 --> 00:51:42,080 Speaker 1: can't ever see what's inside a black hole, we might 1007 00:51:42,120 --> 00:51:44,720 Speaker 1: be able to develop a pretty strong theory for what's 1008 00:51:44,719 --> 00:51:48,399 Speaker 1: going on based on its impacts on the outside. If 1009 00:51:48,440 --> 00:51:51,200 Speaker 1: we can build a theory which very accurately predicts what's 1010 00:51:51,239 --> 00:51:54,600 Speaker 1: going on outside black holes, or predicts what happens in 1011 00:51:54,680 --> 00:51:56,880 Speaker 1: areas we haven't seen yet, we could still test it 1012 00:51:57,040 --> 00:51:59,880 Speaker 1: outside the black hole. And draw conclusions about what might 1013 00:52:00,040 --> 00:52:03,680 Speaker 1: be going on inside. Wow, pretty cool. And what's amazing 1014 00:52:03,719 --> 00:52:05,359 Speaker 1: is that we can do that from all the way 1015 00:52:05,520 --> 00:52:08,560 Speaker 1: out here, right, Like we are along distance away from 1016 00:52:08,600 --> 00:52:10,239 Speaker 1: this black hole. It's not like you can see it 1017 00:52:10,239 --> 00:52:12,480 Speaker 1: in the night sky. It's like it's hidden inside of 1018 00:52:12,480 --> 00:52:16,000 Speaker 1: a whole galaxy even right exactly, And each galaxy itself 1019 00:52:16,080 --> 00:52:18,560 Speaker 1: is quite faint, right, this one is really really far away. 1020 00:52:18,560 --> 00:52:20,800 Speaker 1: It's much further away than Andromeda. So it's in the 1021 00:52:20,920 --> 00:52:23,279 Speaker 1: nice guy. It's just like a fuzzy little dot. But 1022 00:52:23,400 --> 00:52:27,040 Speaker 1: these radio telescopes are very powerful, and so using a 1023 00:52:27,200 --> 00:52:31,520 Speaker 1: huge telescope sort of like get pictures with slightly different angles, 1024 00:52:31,760 --> 00:52:33,960 Speaker 1: and then we can figure out something about the dynamics 1025 00:52:33,960 --> 00:52:36,239 Speaker 1: of what's going on the heart of that galaxy. And 1026 00:52:36,280 --> 00:52:38,520 Speaker 1: we can study that galaxy better than we can study 1027 00:52:38,560 --> 00:52:41,640 Speaker 1: the center of our own galaxy, right because I guess 1028 00:52:41,640 --> 00:52:45,239 Speaker 1: there there aren't that many stars kind of block into view. 1029 00:52:45,360 --> 00:52:47,359 Speaker 1: Is that where is that? What's going on? Two things 1030 00:52:47,400 --> 00:52:49,200 Speaker 1: are happening there. One is that the galaxy is sort 1031 00:52:49,200 --> 00:52:51,200 Speaker 1: of oriented in such a way that we can see 1032 00:52:51,280 --> 00:52:53,759 Speaker 1: it's heart, whereas in the milky Way, we're like right 1033 00:52:53,760 --> 00:52:55,200 Speaker 1: in the middle of it, and there's a lot of 1034 00:52:55,239 --> 00:52:57,560 Speaker 1: gas and dust between us and the center of our 1035 00:52:57,560 --> 00:52:59,839 Speaker 1: galaxy and other stars. As you say, the other thing 1036 00:52:59,880 --> 00:53:02,080 Speaker 1: is that this thing is a monster compared to our 1037 00:53:02,160 --> 00:53:05,319 Speaker 1: black hole, so it's much bigger and it's glowing very 1038 00:53:05,400 --> 00:53:07,840 Speaker 1: very brightly, whereas our black hole in the center of 1039 00:53:07,840 --> 00:53:11,080 Speaker 1: the Milky Way. Sagittarius a star is not as big. 1040 00:53:11,120 --> 00:53:13,319 Speaker 1: I mean, it's quite impressive, but if we don't think 1041 00:53:13,320 --> 00:53:16,040 Speaker 1: it's a quaisar, and they might or might not have 1042 00:53:16,280 --> 00:53:19,080 Speaker 1: sort of faint astrophysical jets for us to study, but 1043 00:53:19,160 --> 00:53:21,759 Speaker 1: we'll know soon. Because the same group is hoping to 1044 00:53:21,800 --> 00:53:24,800 Speaker 1: point their ritual event horizon telescope at the center of 1045 00:53:24,840 --> 00:53:27,440 Speaker 1: our galaxy and try to take a picture of Sagittarius 1046 00:53:27,480 --> 00:53:29,759 Speaker 1: a Star. Well, they've been pointing at it all this time, 1047 00:53:29,800 --> 00:53:32,160 Speaker 1: and it's it's just that the images from this larger 1048 00:53:32,200 --> 00:53:36,359 Speaker 1: black hole were sort of easier or radio sooner, right, Yeah, Well, 1049 00:53:36,360 --> 00:53:38,880 Speaker 1: they need dedicated time on these radio telescopes, which are 1050 00:53:38,880 --> 00:53:40,719 Speaker 1: of course, you know, of interest for lots of other 1051 00:53:40,719 --> 00:53:43,839 Speaker 1: things like searching for intelligent life and looking for exoplanets 1052 00:53:43,840 --> 00:53:46,520 Speaker 1: and whatever. So you need dedicated, coordinated time on all 1053 00:53:46,560 --> 00:53:49,200 Speaker 1: of these telescopes. In order to gather this data. So 1054 00:53:49,280 --> 00:53:51,200 Speaker 1: if you've ever wonder what a black hole looks like 1055 00:53:51,280 --> 00:53:52,919 Speaker 1: or want to see what it looks like just looking 1056 00:53:52,960 --> 00:53:55,759 Speaker 1: up on the internet black hole photo. Although we think 1057 00:53:55,800 --> 00:53:57,560 Speaker 1: it's a black hole, right, we talked last time about 1058 00:53:57,600 --> 00:54:00,200 Speaker 1: how it could just be maybe a really a dark 1059 00:54:00,239 --> 00:54:03,040 Speaker 1: star or a neutron star. Right, Yeah, we don't actually know. 1060 00:54:03,160 --> 00:54:06,400 Speaker 1: All of this information is indirect. Most of the evidence 1061 00:54:06,520 --> 00:54:10,000 Speaker 1: is it's something, it's very massive, it's very small, and 1062 00:54:10,080 --> 00:54:12,879 Speaker 1: black hole is the only thing we think that fit 1063 00:54:12,960 --> 00:54:15,200 Speaker 1: the bill. Though there are some folks out there coming 1064 00:54:15,280 --> 00:54:18,359 Speaker 1: up with other crazy ideas, like dark stars which are 1065 00:54:18,520 --> 00:54:21,719 Speaker 1: powered by quantum mechanics and not actually having event horizon. 1066 00:54:22,160 --> 00:54:24,120 Speaker 1: So maybe one day we'll just have to get closer 1067 00:54:24,120 --> 00:54:25,880 Speaker 1: so we can see one of these things with our 1068 00:54:25,920 --> 00:54:28,200 Speaker 1: own eyes. Yeah, it could be like a gray hole. 1069 00:54:28,239 --> 00:54:31,520 Speaker 1: We talked about that last time. Yeah, So another awesome 1070 00:54:31,560 --> 00:54:34,399 Speaker 1: reminder of how mysterious the universe is, but also how 1071 00:54:34,440 --> 00:54:37,680 Speaker 1: discoverable it is if we can eventually get pictures of 1072 00:54:37,719 --> 00:54:40,640 Speaker 1: it and maybe even figure out what's going on inside 1073 00:54:40,680 --> 00:54:43,160 Speaker 1: of the texture of the black hole itself, and how 1074 00:54:43,200 --> 00:54:46,400 Speaker 1: physics and math can really guide is to an understanding 1075 00:54:46,480 --> 00:54:50,040 Speaker 1: of the craziest corners of the universe, so that even 1076 00:54:50,120 --> 00:54:53,200 Speaker 1: things like black holes and astrophysical jets can start to 1077 00:54:53,280 --> 00:54:56,000 Speaker 1: make sense to you and to me. Physics and math, 1078 00:54:56,040 --> 00:54:58,879 Speaker 1: how would you combine those two words? And fast fath 1079 00:54:59,000 --> 00:55:05,680 Speaker 1: fast math mimsis mrs me, that's the one. I'm a methodist, yours? 1080 00:55:06,400 --> 00:55:08,279 Speaker 1: Are you a mystic? Is that what you're saying. I'm 1081 00:55:08,280 --> 00:55:11,840 Speaker 1: a mythical feature, I'm a mythical figure, you're mathematical mystical 1082 00:55:12,400 --> 00:55:16,080 Speaker 1: most on his cosmic quest for understanding the contextual clues 1083 00:55:16,520 --> 00:55:19,400 Speaker 1: of the cosmos. Yeah. Well, we hope they gave you 1084 00:55:19,440 --> 00:55:21,520 Speaker 1: a lot to think about and we hope you enjoyed that. 1085 00:55:21,880 --> 00:55:32,600 Speaker 1: Thanks for joining us, See you next time. Thanks for listening, 1086 00:55:32,600 --> 00:55:35,320 Speaker 1: and remember that Daniel and Jorge explained the universe is 1087 00:55:35,360 --> 00:55:38,759 Speaker 1: a production of I Heart Radio. For more podcast for 1088 00:55:38,880 --> 00:55:42,640 Speaker 1: my heart Radio, visit the I heart Radio app, Apple Podcasts, 1089 00:55:42,760 --> 00:55:50,720 Speaker 1: or wherever you listen to your favorite shows. Ye