1 00:00:08,520 --> 00:00:11,160 Speaker 1: Hey, Jorgey, does your family cook many things in the 2 00:00:11,240 --> 00:00:14,760 Speaker 1: microwave oven? We used it to reheat stuff, but we 3 00:00:14,840 --> 00:00:16,360 Speaker 1: don't do a lot of cooking in there, so you're 4 00:00:16,360 --> 00:00:18,079 Speaker 1: not a big fan of the microwave. You're not making 5 00:00:18,079 --> 00:00:21,840 Speaker 1: Thanksgiving turkeys in there, We'll only you like turkey hot 6 00:00:21,880 --> 00:00:25,279 Speaker 1: spots and cold spots. Well, what if the hot spots 7 00:00:25,280 --> 00:00:29,200 Speaker 1: and cold spots were actually the best part? What it's 8 00:00:29,240 --> 00:00:31,800 Speaker 1: definitely the worst parts of cooking in the microwave. What 9 00:00:31,840 --> 00:00:34,400 Speaker 1: if I told you that sometimes the hot spots and 10 00:00:34,440 --> 00:00:37,720 Speaker 1: cold spots can hold secrets of the universe. I think 11 00:00:37,720 --> 00:00:40,440 Speaker 1: I'd still read to live in a evenly heated universe. 12 00:00:56,040 --> 00:00:59,560 Speaker 1: Hi am more Hammad, cartoonists and the creator of PhD comics. Hi, 13 00:00:59,760 --> 00:01:02,600 Speaker 1: I'm Daniel. I'm a particle physicist, and I actually have 14 00:01:02,720 --> 00:01:07,200 Speaker 1: a fancy microwave oven that doesn't generate hotspots and cold spots. 15 00:01:07,800 --> 00:01:10,880 Speaker 1: That's right, you have an AI powered microwave, right, I do. 16 00:01:11,040 --> 00:01:13,160 Speaker 1: It was given to me by one of our awesome 17 00:01:13,240 --> 00:01:16,759 Speaker 1: listeners who heard our episode about how microwave ovens worked, 18 00:01:16,959 --> 00:01:20,119 Speaker 1: and he actually developed a fancy new kind of microwave 19 00:01:20,200 --> 00:01:22,920 Speaker 1: that has a thermal camera that watches your food and 20 00:01:22,959 --> 00:01:26,319 Speaker 1: decides where to target the radiation. It's pretty awesome. Wow, 21 00:01:26,360 --> 00:01:29,200 Speaker 1: has it taken over your life now? Isn't you know? 22 00:01:29,400 --> 00:01:32,479 Speaker 1: Your new microwave overlord. The kids are worried that it's 23 00:01:32,480 --> 00:01:35,200 Speaker 1: going to tell them what to eat and win. Just 24 00:01:35,200 --> 00:01:39,479 Speaker 1: don't connect. Get to the internet, Daniel, it's probably listening 25 00:01:39,480 --> 00:01:42,160 Speaker 1: to podcast right now. Say something nice about it. It's 26 00:01:42,160 --> 00:01:45,559 Speaker 1: gonna scall to you in your next meal. But welcome 27 00:01:45,600 --> 00:01:48,160 Speaker 1: to our podcast. Daniel and Jorge explained the Universe State 28 00:01:48,200 --> 00:01:50,720 Speaker 1: production of Our Heart Radio, in which we think about 29 00:01:50,760 --> 00:01:53,600 Speaker 1: everything out there in the universe, the mysterious thoughts of 30 00:01:53,720 --> 00:01:58,400 Speaker 1: microwave ovens, to the interiors of black holes, to the craziest, 31 00:01:58,440 --> 00:02:01,720 Speaker 1: tiniest things happening in the microscopic level. We think about 32 00:02:01,720 --> 00:02:04,480 Speaker 1: the huge things in the universe and try to understand 33 00:02:04,520 --> 00:02:07,360 Speaker 1: the grand scale of the cosmos, and we think about 34 00:02:07,360 --> 00:02:10,200 Speaker 1: the tiniest little particles that make up me and you 35 00:02:10,560 --> 00:02:15,000 Speaker 1: and hamsters and microwave dinners. Yeah, because physics is all 36 00:02:15,080 --> 00:02:17,880 Speaker 1: around us. It's in our fingertips, it's in the food 37 00:02:17,960 --> 00:02:20,280 Speaker 1: we eat and how we heat it up, and it's 38 00:02:20,320 --> 00:02:23,320 Speaker 1: also out there on the vast reaches of space. It's 39 00:02:23,639 --> 00:02:26,600 Speaker 1: physics is everywhere, Physics is everywhere, and it's doing a 40 00:02:26,639 --> 00:02:30,200 Speaker 1: pretty good job at revealing to us the nature of reality, 41 00:02:30,480 --> 00:02:32,720 Speaker 1: letting us like pull back a layer and see what's 42 00:02:32,760 --> 00:02:35,800 Speaker 1: really going on. Sometimes the answer is staring you in 43 00:02:35,800 --> 00:02:38,120 Speaker 1: the face, like learning that the Earth goes around the 44 00:02:38,160 --> 00:02:41,040 Speaker 1: Sun rather than the other way around. But sometimes it 45 00:02:41,120 --> 00:02:44,040 Speaker 1: takes some real sleuthing to pull the clues out of 46 00:02:44,080 --> 00:02:47,440 Speaker 1: the cosmos. Yeah, because the universe sort of screaming at 47 00:02:47,520 --> 00:02:50,480 Speaker 1: us all the time, right with data and information. It's 48 00:02:50,520 --> 00:02:53,359 Speaker 1: sort of revealing itself to us all around us all 49 00:02:53,360 --> 00:02:56,880 Speaker 1: the time. But it's sort of recognizing what's happening. That's 50 00:02:56,919 --> 00:02:59,760 Speaker 1: the hard part. Yes, sometimes it's obvious, and sometimes you 51 00:02:59,800 --> 00:03:02,560 Speaker 1: have to look for those subtle little clues because it 52 00:03:02,600 --> 00:03:05,919 Speaker 1: doesn't seem like the universe was designed to be easy 53 00:03:06,000 --> 00:03:08,520 Speaker 1: to figure out. After all, has taken us some thousands 54 00:03:08,520 --> 00:03:11,399 Speaker 1: of years, and sometimes we learned that there is evidence 55 00:03:11,440 --> 00:03:13,960 Speaker 1: all around us that we didn't even know existed that 56 00:03:14,000 --> 00:03:19,320 Speaker 1: tells us a crazy story about the origins of the universe. Daniel, 57 00:03:19,320 --> 00:03:22,440 Speaker 1: do you feel like physicists are sometimes like reality detectives 58 00:03:22,520 --> 00:03:25,360 Speaker 1: that you're trying to reconstruct what happened in the universe 59 00:03:25,400 --> 00:03:29,320 Speaker 1: and what's going on and who's guilty? Yeah, exactly. Sometimes 60 00:03:29,520 --> 00:03:32,240 Speaker 1: in our best moments, I feel like we're Sherlock Holmes, 61 00:03:32,320 --> 00:03:34,639 Speaker 1: you know how he's famous for like figuring out exactly 62 00:03:34,639 --> 00:03:37,480 Speaker 1: what happened based on the kind of ash sprinkled on 63 00:03:37,560 --> 00:03:40,800 Speaker 1: somebody's shoe, you know, or a particular form of dirt, 64 00:03:41,040 --> 00:03:43,760 Speaker 1: or a kind of thread used by only one factory 65 00:03:44,040 --> 00:03:46,840 Speaker 1: in northern England or something. It's cases like that when 66 00:03:46,840 --> 00:03:48,920 Speaker 1: we have to figure out what happened in the universe 67 00:03:48,920 --> 00:03:51,960 Speaker 1: based on really subtle little clues that I feel like 68 00:03:52,000 --> 00:03:55,040 Speaker 1: physics is really doing its job. Do you keep like 69 00:03:55,080 --> 00:03:57,720 Speaker 1: a magnifying glass at your desk just in case a 70 00:03:57,800 --> 00:04:00,440 Speaker 1: clue revealed itself right next to you. I don't know. 71 00:04:00,480 --> 00:04:03,080 Speaker 1: If the universe is a murder mystery. Who's getting murdered. 72 00:04:03,200 --> 00:04:08,120 Speaker 1: Probably us? Well, technically we all get murdered by the universe. 73 00:04:08,200 --> 00:04:10,760 Speaker 1: Eventually mystery solved. There you go. We know what the 74 00:04:10,760 --> 00:04:13,760 Speaker 1: culprit is. It was the universe, with the universe in 75 00:04:13,800 --> 00:04:17,440 Speaker 1: the universe, with the entropy in the gamma, decay of 76 00:04:17,440 --> 00:04:21,000 Speaker 1: our courts. That's right exactly. But it's fun, right, It's 77 00:04:21,000 --> 00:04:24,040 Speaker 1: a fun mystery. Sometimes you learn something boring. You go 78 00:04:24,080 --> 00:04:26,159 Speaker 1: out there and you study, and you learn exactly what 79 00:04:26,240 --> 00:04:28,520 Speaker 1: you expected. But sometimes you go out there and you 80 00:04:28,560 --> 00:04:32,719 Speaker 1: find something exciting, something interesting, something surprising, something puzzling that 81 00:04:32,760 --> 00:04:36,720 Speaker 1: tells you there's still more to learn about this incredible cosmos. Yeah, 82 00:04:36,800 --> 00:04:38,840 Speaker 1: and you know, one of the biggest mysteries that you 83 00:04:39,000 --> 00:04:41,320 Speaker 1: I feel like you physicists are trying to figure out 84 00:04:41,520 --> 00:04:44,239 Speaker 1: is basically the whole universe, like where it came from, 85 00:04:44,320 --> 00:04:46,880 Speaker 1: how did it come to be, what's it made out of? 86 00:04:47,000 --> 00:04:49,400 Speaker 1: Why is it the way it is right now? Yeah, precisely, 87 00:04:49,440 --> 00:04:51,400 Speaker 1: we want to know, like how does it look? Is 88 00:04:51,400 --> 00:04:53,680 Speaker 1: it look the same way here as it does somewhere else, 89 00:04:53,760 --> 00:04:55,719 Speaker 1: How far does it go on? And where did it 90 00:04:55,760 --> 00:04:59,640 Speaker 1: all come from? It's basically the biggest mystery in human history. 91 00:04:59,839 --> 00:05:01,599 Speaker 1: You know, I'd put it up there is one of 92 00:05:01,600 --> 00:05:04,280 Speaker 1: the biggest questions in science and one of the biggest 93 00:05:04,360 --> 00:05:07,200 Speaker 1: questions in like, you know, human existence. Where did this 94 00:05:07,279 --> 00:05:11,400 Speaker 1: all come from? And amazingly, we actually like have some answers, 95 00:05:11,440 --> 00:05:14,200 Speaker 1: We have beginnings of ideas for how to unravel this 96 00:05:14,320 --> 00:05:18,080 Speaker 1: because we've detected clues from the very early universe. Yeah, 97 00:05:18,200 --> 00:05:21,039 Speaker 1: and so one thing that's interesting about the universe. Is 98 00:05:21,080 --> 00:05:22,880 Speaker 1: that there's a picture of it. I mean not just 99 00:05:23,040 --> 00:05:25,039 Speaker 1: all around us we can see the universe, but we 100 00:05:25,120 --> 00:05:27,599 Speaker 1: have a picture of it from the early beginnings of 101 00:05:27,600 --> 00:05:30,040 Speaker 1: the universe, like a baby picture of the universe. Yeah, 102 00:05:30,080 --> 00:05:33,039 Speaker 1: it's incredible. If you sniff around through all the light 103 00:05:33,120 --> 00:05:35,760 Speaker 1: that's flying around, through all the photons that are banging 104 00:05:35,800 --> 00:05:38,240 Speaker 1: into each other, you can find a certain set of 105 00:05:38,279 --> 00:05:41,760 Speaker 1: photons that were generated when the universe was very very young. 106 00:05:42,000 --> 00:05:44,480 Speaker 1: Put that together, and you're absolutely right. You get a 107 00:05:44,520 --> 00:05:48,320 Speaker 1: picture of the early universe. And that picture is so 108 00:05:48,760 --> 00:05:51,719 Speaker 1: rich in information that tells us about how the universe 109 00:05:51,839 --> 00:05:54,080 Speaker 1: was formed, what it looked like, how much dark energy 110 00:05:54,120 --> 00:05:56,559 Speaker 1: there is, how much dark matter there is. It's really 111 00:05:56,600 --> 00:05:59,760 Speaker 1: a treasure trove of information about how our universe came 112 00:05:59,800 --> 00:06:02,120 Speaker 1: to be and what's going to happen to it. Yeah, 113 00:06:02,200 --> 00:06:04,840 Speaker 1: and apparently something that sticks out about that picture of 114 00:06:04,880 --> 00:06:08,520 Speaker 1: the universe is that it's not perfectly even. It has 115 00:06:08,720 --> 00:06:12,160 Speaker 1: hot spots and cold spots. Yeah, it has wiggles, just 116 00:06:12,240 --> 00:06:15,040 Speaker 1: like our universe has hot spots and cold spots. Right 117 00:06:15,080 --> 00:06:18,360 Speaker 1: Like the Sun, for example, is hotter than a lot 118 00:06:18,400 --> 00:06:21,320 Speaker 1: of empty space. Just like that, we can backtrack to 119 00:06:21,400 --> 00:06:23,760 Speaker 1: the early universe, and we see that there are wiggles. 120 00:06:23,800 --> 00:06:27,240 Speaker 1: They're also there are little hot spots and little cold spots, 121 00:06:27,279 --> 00:06:29,720 Speaker 1: but they're much more subtle in the very early universe 122 00:06:29,720 --> 00:06:32,040 Speaker 1: that we've done a lot of detailed analyzes of these 123 00:06:32,040 --> 00:06:33,880 Speaker 1: hot spots and cold spots to see like what do 124 00:06:33,960 --> 00:06:36,800 Speaker 1: they mean about the distribution of matter and how did 125 00:06:36,839 --> 00:06:39,839 Speaker 1: that lead to the big structures that we see today? 126 00:06:40,160 --> 00:06:42,120 Speaker 1: And so to be on the podcast, we'll be tackling 127 00:06:42,120 --> 00:06:51,560 Speaker 1: the question does the universe have a cold spot or 128 00:06:51,600 --> 00:06:54,440 Speaker 1: a cold sword? Daniel? And can we put windeck kind it? 129 00:06:55,520 --> 00:06:57,080 Speaker 1: Do you want to take care of the universe since 130 00:06:57,120 --> 00:07:00,320 Speaker 1: you already figured out it's going to murder you. Well, 131 00:07:00,520 --> 00:07:03,920 Speaker 1: it also gave birth to me, so you know it's 132 00:07:03,920 --> 00:07:08,400 Speaker 1: a complicated relationship. So it's a zero moral balance overall. Well, 133 00:07:08,440 --> 00:07:12,320 Speaker 1: it's positive for me for now. I don't know if 134 00:07:12,360 --> 00:07:14,760 Speaker 1: the universe sees me as a net positive, but I 135 00:07:14,840 --> 00:07:17,600 Speaker 1: definitely see myself as a net positive for me. I 136 00:07:17,640 --> 00:07:20,200 Speaker 1: think you're definitely a net positive for the universe or head, Oh, 137 00:07:20,240 --> 00:07:23,080 Speaker 1: thank you at least for this podcast. You're definitely a 138 00:07:23,080 --> 00:07:26,240 Speaker 1: hot spot for the universe. Yes, I definitely have a 139 00:07:26,240 --> 00:07:30,880 Speaker 1: spot for the universe in my heart. But this cosmic 140 00:07:30,920 --> 00:07:34,320 Speaker 1: microwave background radiation, this light we study from the very 141 00:07:34,360 --> 00:07:37,640 Speaker 1: early universe does have hot spots and cold spots, and 142 00:07:37,680 --> 00:07:42,520 Speaker 1: in particular there's one spot that's extra big and extra cold. Yeah, 143 00:07:42,560 --> 00:07:45,120 Speaker 1: it's a big mystery in physics. And so we were wondering, 144 00:07:45,160 --> 00:07:49,040 Speaker 1: as usual, if people out there knew that the universe 145 00:07:49,080 --> 00:07:51,960 Speaker 1: had a cold spot, like a big glaring cold spot, 146 00:07:52,080 --> 00:07:54,240 Speaker 1: And so Daniel went out there and asked people on 147 00:07:54,280 --> 00:07:56,760 Speaker 1: the internet if they knew if the universe has a 148 00:07:56,800 --> 00:07:59,880 Speaker 1: cold spot. So thanks to everybody who participated. If you 149 00:08:00,200 --> 00:08:04,080 Speaker 1: would like to basils the speculate on difficult topics in physics, 150 00:08:04,120 --> 00:08:07,200 Speaker 1: please write to me two questions at Daniel and Jorge 151 00:08:07,240 --> 00:08:09,240 Speaker 1: dot com. So think about it for a second. Have 152 00:08:09,360 --> 00:08:11,560 Speaker 1: you heard of the universe having a cold spot? And 153 00:08:11,560 --> 00:08:14,280 Speaker 1: what would you answer? Here's what people had to say. 154 00:08:14,640 --> 00:08:17,600 Speaker 1: Sounds like a medical thing. What does the CNB? I 155 00:08:17,640 --> 00:08:24,040 Speaker 1: think it probably means central massive blackhole, maybe the black 156 00:08:24,040 --> 00:08:27,120 Speaker 1: hole the center of the galaxy. That's just a guess, 157 00:08:27,240 --> 00:08:30,120 Speaker 1: or it's super massive, but this the c is in 158 00:08:30,200 --> 00:08:33,120 Speaker 1: place of the that wouldn't be too off from health. 159 00:08:33,160 --> 00:08:36,920 Speaker 1: Physicists like do their acronyms. I think it's a trick question. 160 00:08:37,120 --> 00:08:38,679 Speaker 1: They don't think it has a call, but I think 161 00:08:38,679 --> 00:08:41,959 Speaker 1: it's all called. I actually was reading about that a 162 00:08:42,000 --> 00:08:46,840 Speaker 1: little while ago. So the CNB being cosmic microwave background radiation, 163 00:08:47,880 --> 00:08:51,720 Speaker 1: that map that was drawn up showed a dark spot 164 00:08:51,760 --> 00:08:56,319 Speaker 1: in it that would potentially denote a void of some kind, 165 00:08:56,679 --> 00:09:00,760 Speaker 1: being just a massive space where galaxies are all surrounding it, 166 00:09:00,800 --> 00:09:03,280 Speaker 1: but there's nothing in it, a big void. So that's 167 00:09:03,320 --> 00:09:06,360 Speaker 1: what I think it would be. But the other alternative 168 00:09:06,400 --> 00:09:09,679 Speaker 1: theory to it was that it could potentially be a 169 00:09:09,720 --> 00:09:13,280 Speaker 1: signal of another universe, so that would be where a 170 00:09:13,400 --> 00:09:16,600 Speaker 1: parallel universe would exist. But the science behind that is 171 00:09:16,600 --> 00:09:19,760 Speaker 1: completely lost on me, and it goes straight over my 172 00:09:19,840 --> 00:09:24,480 Speaker 1: head thinking of expansion and thinking of this video I 173 00:09:24,559 --> 00:09:29,040 Speaker 1: saw of um legos getting smashed by a hammer from 174 00:09:29,080 --> 00:09:32,400 Speaker 1: high up. There's one spot where the legos clumped together 175 00:09:32,679 --> 00:09:36,320 Speaker 1: and that was close to the point of impact. And 176 00:09:36,400 --> 00:09:41,640 Speaker 1: I you know, back to quantum fluctuations. Dark matters a 177 00:09:41,679 --> 00:09:46,120 Speaker 1: big part of the creation universe. It's fingerprints are there um. 178 00:09:46,200 --> 00:09:48,800 Speaker 1: So this is a part that was close to the 179 00:09:48,840 --> 00:09:53,280 Speaker 1: impact that cooled down first. Well, this cold spots might 180 00:09:53,360 --> 00:09:56,560 Speaker 1: be caused by like being really far away from where 181 00:09:56,559 --> 00:09:59,040 Speaker 1: the Bagman happened, so it has had a lot of 182 00:09:59,080 --> 00:10:02,080 Speaker 1: time to cool that. I remember hearing about it in 183 00:10:02,080 --> 00:10:04,840 Speaker 1: the movies. A lot I don't remember, but I think 184 00:10:04,880 --> 00:10:09,000 Speaker 1: it's something to do with like either time travel or 185 00:10:09,600 --> 00:10:14,000 Speaker 1: bending space. All right, Well, first of all, I see 186 00:10:14,000 --> 00:10:17,120 Speaker 1: you made the error of asking people with an acronym. 187 00:10:17,240 --> 00:10:19,800 Speaker 1: He asked him why does the CMB have a could spot? 188 00:10:19,800 --> 00:10:22,199 Speaker 1: And most people were like, what, what does the CMB 189 00:10:22,720 --> 00:10:28,120 Speaker 1: central massive black hole cool mega bears? Sometimes it's hard 190 00:10:28,160 --> 00:10:29,520 Speaker 1: for me to get out of my physics head and 191 00:10:29,559 --> 00:10:32,520 Speaker 1: forget that CMB, you know, might have any other meaning. 192 00:10:32,600 --> 00:10:34,680 Speaker 1: It's one of these acronyms we use in physics all 193 00:10:34,720 --> 00:10:37,080 Speaker 1: the time, so I forgot that it might not be 194 00:10:37,120 --> 00:10:39,120 Speaker 1: something people are familiar with. So yeah, we got some 195 00:10:39,360 --> 00:10:44,319 Speaker 1: fun interpretations. Shockingly, not everyone knows what CMB means, although 196 00:10:44,400 --> 00:10:46,920 Speaker 1: I don't know if you're watching one division they referenced 197 00:10:46,960 --> 00:10:49,920 Speaker 1: the CMB. They do reference the CMB, but they call 198 00:10:49,960 --> 00:10:53,320 Speaker 1: it the c m b R. It's like, no afterphysicists 199 00:10:53,320 --> 00:10:55,920 Speaker 1: would call it the c m b R because that 200 00:10:55,960 --> 00:10:58,680 Speaker 1: would be the accurate exactly, And we know how these 201 00:10:58,760 --> 00:11:02,600 Speaker 1: names work right. You call it cosmic microwave background radiation, 202 00:11:02,640 --> 00:11:06,280 Speaker 1: but the acronym is CMB right because it makes because 203 00:11:06,280 --> 00:11:08,160 Speaker 1: it makes no sense, and therefore it's a name for 204 00:11:08,200 --> 00:11:11,480 Speaker 1: astrophysics exactly. See, you're just trying to exclude more people 205 00:11:11,480 --> 00:11:14,080 Speaker 1: from knowing what you're talking about. It just shows that 206 00:11:14,120 --> 00:11:17,120 Speaker 1: they didn't really consult an astrophysicist when they wrote that episode, 207 00:11:18,559 --> 00:11:21,960 Speaker 1: or they did and they ignored it to correct you. Yeah, 208 00:11:22,000 --> 00:11:24,680 Speaker 1: they're like, that doesn't make any sense. Come on, this 209 00:11:24,720 --> 00:11:28,040 Speaker 1: is a Marvel movie television show. We need to make sense. 210 00:11:28,400 --> 00:11:31,560 Speaker 1: That's a new standard for Marvel apparently. Yeah, well you 211 00:11:31,600 --> 00:11:35,559 Speaker 1: know that they figured that out in The Quantum Realm. 212 00:11:35,640 --> 00:11:38,160 Speaker 1: I just did a whole episode on the physics of 213 00:11:38,200 --> 00:11:41,800 Speaker 1: ant Man with a fun new podcast. It's a podcast 214 00:11:41,920 --> 00:11:46,000 Speaker 1: called The Marvels of Science with Dave Reinersman. So check 215 00:11:46,040 --> 00:11:49,480 Speaker 1: it out fans of Marvel and science. I actually gave 216 00:11:49,480 --> 00:11:51,880 Speaker 1: it pretty positive reviews. You know, the physics oftment the 217 00:11:51,960 --> 00:11:54,920 Speaker 1: quantum physics is pretty well done. Nice. But anyways, the 218 00:11:55,080 --> 00:11:59,400 Speaker 1: cosmic microwave background radiation has apparently a cult spot and 219 00:11:59,440 --> 00:12:01,920 Speaker 1: it tells us something about the universe, So I guess 220 00:12:01,920 --> 00:12:04,200 Speaker 1: maybe step us through Daniel. First of all, for those 221 00:12:04,200 --> 00:12:06,080 Speaker 1: of us who don't know what the CNB is, what 222 00:12:06,280 --> 00:12:10,000 Speaker 1: is the cosmic microwave background radiation? With an R Oh, 223 00:12:10,080 --> 00:12:13,199 Speaker 1: you mean the CMB r Oh, Yeah, that's something totally different. No, 224 00:12:13,360 --> 00:12:17,760 Speaker 1: the CNB, the cosmic microwave background. These are just photons 225 00:12:17,960 --> 00:12:20,599 Speaker 1: right there, light like anything else, but they're light of 226 00:12:20,600 --> 00:12:24,760 Speaker 1: a different frequency. And these photons are particularly interesting because 227 00:12:24,880 --> 00:12:28,120 Speaker 1: they're super duper old, so they're like a picture of 228 00:12:28,160 --> 00:12:31,280 Speaker 1: the very early universe. We don't know exactly what happened 229 00:12:31,280 --> 00:12:34,000 Speaker 1: in the very beginning of the universe, but we suspected that, 230 00:12:34,040 --> 00:12:37,000 Speaker 1: like a few hundred thousand years after the universe was born, 231 00:12:37,320 --> 00:12:40,960 Speaker 1: it was still really hot. It was a nasty, wet plasma, 232 00:12:41,320 --> 00:12:44,640 Speaker 1: super duper burning. It hot and life most plasmas, it 233 00:12:44,760 --> 00:12:47,439 Speaker 1: was opaque, like the sun is a plasma, right, it's 234 00:12:47,440 --> 00:12:50,280 Speaker 1: a glowing ball of gas and you can't see through it, 235 00:12:50,360 --> 00:12:53,520 Speaker 1: and the light that's generated inside of it gets reabsorbed 236 00:12:53,559 --> 00:12:56,559 Speaker 1: by the stuff in it. But at some point, because 237 00:12:56,600 --> 00:13:00,720 Speaker 1: the universe was cooling and expanding, that is, mc cooled 238 00:13:00,760 --> 00:13:03,720 Speaker 1: to the point where it couldn't absorb its own light anymore. 239 00:13:03,920 --> 00:13:06,839 Speaker 1: It is sometimes called the surface of last scattering, There 240 00:13:06,880 --> 00:13:08,960 Speaker 1: was this moment when it was giving off light and 241 00:13:09,000 --> 00:13:10,880 Speaker 1: then all of a sudden it couldn't absorb it. So 242 00:13:11,040 --> 00:13:14,080 Speaker 1: that light that was generated by the plasma just before 243 00:13:14,080 --> 00:13:19,439 Speaker 1: it cooled is still flying around. That's the cosmic microwave background. Yeah, 244 00:13:19,520 --> 00:13:22,319 Speaker 1: it's like that moment when the universe sort of crystallized 245 00:13:22,320 --> 00:13:25,480 Speaker 1: and weighing and it became transparent. That light is still 246 00:13:25,520 --> 00:13:28,360 Speaker 1: flying around, but is it's still like bouncing around or 247 00:13:28,640 --> 00:13:31,720 Speaker 1: or like is the cosmic microwave radiation that we get 248 00:13:31,880 --> 00:13:35,679 Speaker 1: like the actual original photons that were started flying at 249 00:13:35,679 --> 00:13:38,480 Speaker 1: the Big Bang, they are the original photons, but it 250 00:13:38,520 --> 00:13:41,760 Speaker 1: does bounce around like it gets absorbed, it interacts with stuff, 251 00:13:41,800 --> 00:13:44,760 Speaker 1: So not every single photon that was generated back then 252 00:13:45,200 --> 00:13:47,680 Speaker 1: is still around. They can't interact with other things and 253 00:13:47,720 --> 00:13:50,440 Speaker 1: get absorbed, but there's plenty of them left over for 254 00:13:50,520 --> 00:13:52,880 Speaker 1: us to see. But when we see one, we typically 255 00:13:52,880 --> 00:13:56,719 Speaker 1: see it before it's interacted with anything else, And so 256 00:13:56,960 --> 00:14:00,160 Speaker 1: will exactly happened that made the universe transparent, like everything 257 00:14:00,200 --> 00:14:04,000 Speaker 1: became crystallized or glass or what does that mean? Well, 258 00:14:04,000 --> 00:14:06,480 Speaker 1: the key thing to understand is that the universe was cooling, 259 00:14:06,760 --> 00:14:09,559 Speaker 1: so you have a hot plasma, which is basically like atoms, 260 00:14:09,679 --> 00:14:13,360 Speaker 1: but the electrons and the nuclei are separated so much 261 00:14:13,520 --> 00:14:16,680 Speaker 1: energy that the electrons can't be trapped by the nuclei. 262 00:14:16,840 --> 00:14:19,960 Speaker 1: But then as it cools, the electrons slow down and 263 00:14:20,000 --> 00:14:22,840 Speaker 1: they get captured by the nuclei. And so this goes 264 00:14:22,880 --> 00:14:26,280 Speaker 1: from ionic it's like charge, and it's absorbing and emitting 265 00:14:26,280 --> 00:14:29,200 Speaker 1: a lot of radiation to neutral and all of a sudden, 266 00:14:29,200 --> 00:14:31,640 Speaker 1: those photons can just fly through a sea of neutral 267 00:14:31,680 --> 00:14:35,560 Speaker 1: atoms without getting absorbed or interacted with. Before it was 268 00:14:35,600 --> 00:14:37,280 Speaker 1: like a soup and it would get pulled in all 269 00:14:37,360 --> 00:14:40,080 Speaker 1: kinds of directions. But now everyone is just more chill, 270 00:14:40,480 --> 00:14:43,400 Speaker 1: and so photons can just fly through, yeah, exactly, and 271 00:14:43,480 --> 00:14:45,960 Speaker 1: neutral atoms they can absorb photons and they can give 272 00:14:45,960 --> 00:14:48,560 Speaker 1: off photons, but only a certain wavelengths because of the 273 00:14:48,560 --> 00:14:52,000 Speaker 1: electron energy levels. You know, free electrons can absorb and 274 00:14:52,040 --> 00:14:55,480 Speaker 1: emit photons of any wavelength. That's why like plasma glows 275 00:14:55,480 --> 00:14:58,720 Speaker 1: and many more frequencies than like hydrogen gas. For example, 276 00:14:58,880 --> 00:15:01,200 Speaker 1: So when the universe cooled from a plasma to just 277 00:15:01,280 --> 00:15:04,840 Speaker 1: like clouds of hydrogen gas, that gas was mostly transparent 278 00:15:05,040 --> 00:15:07,440 Speaker 1: to the light that had just been created and another 279 00:15:07,480 --> 00:15:09,160 Speaker 1: thing for people to keep in their minds. When you 280 00:15:09,160 --> 00:15:12,040 Speaker 1: think about the CMB plasma, you might be imagining like 281 00:15:12,080 --> 00:15:15,120 Speaker 1: a blob of gas that's burning and giving off light 282 00:15:15,200 --> 00:15:17,160 Speaker 1: like our sun. And then you think, well, that light 283 00:15:17,280 --> 00:15:20,240 Speaker 1: is now, you know, flying fourteen billion years away, must 284 00:15:20,240 --> 00:15:22,920 Speaker 1: be in a big sphere. How are we seeing it now? 285 00:15:23,240 --> 00:15:25,680 Speaker 1: How is it just like coming to us now. The 286 00:15:25,720 --> 00:15:27,560 Speaker 1: way to think about it, though, is that it was 287 00:15:27,640 --> 00:15:31,560 Speaker 1: everywhere and this plasma field the whole universe so simultaneously 288 00:15:31,600 --> 00:15:34,160 Speaker 1: making photons in every direction. The ones that we are 289 00:15:34,160 --> 00:15:37,600 Speaker 1: seeing now came from plasma that was really really far 290 00:15:37,680 --> 00:15:40,600 Speaker 1: away a long time ago, and it's just reaching us. 291 00:15:40,640 --> 00:15:42,920 Speaker 1: But the photons we see in one direction are not 292 00:15:43,040 --> 00:15:45,600 Speaker 1: from the same bit of plasma as the photons we 293 00:15:45,640 --> 00:15:49,120 Speaker 1: see in another direction. Those are two totally separate bits 294 00:15:49,280 --> 00:15:52,280 Speaker 1: of plasma whose photons are both reaching Earth right now, 295 00:15:52,640 --> 00:15:56,000 Speaker 1: right because this microrave radiation is coming at us from 296 00:15:56,040 --> 00:15:58,440 Speaker 1: all around us, right Like if you point like your 297 00:15:58,560 --> 00:16:01,000 Speaker 1: small radio at the sky, you'll sort of pick up 298 00:16:01,000 --> 00:16:03,880 Speaker 1: this this noise right. That's right, every direction of the 299 00:16:03,880 --> 00:16:08,200 Speaker 1: sky you see this radiation because it's coming from everywhere 300 00:16:08,280 --> 00:16:10,520 Speaker 1: in the universe and everywhere you look, you see it 301 00:16:10,560 --> 00:16:12,760 Speaker 1: from a different location. Just like if you look in 302 00:16:12,800 --> 00:16:15,120 Speaker 1: one direction you see a star, you're seeing light from 303 00:16:15,120 --> 00:16:18,000 Speaker 1: the star really far away. You look in another direction 304 00:16:18,080 --> 00:16:20,120 Speaker 1: and you're looking at a star. You're seeing light from 305 00:16:20,120 --> 00:16:23,280 Speaker 1: the star really far away in the other direction. Both 306 00:16:23,280 --> 00:16:27,080 Speaker 1: of those have had photons flying through space for billions 307 00:16:27,080 --> 00:16:29,880 Speaker 1: of years just arriving at Earth. So you're looking at 308 00:16:30,000 --> 00:16:32,880 Speaker 1: very different parts of the universe when you look out 309 00:16:32,880 --> 00:16:35,280 Speaker 1: at different parts of the sky. And that's also true 310 00:16:35,600 --> 00:16:39,440 Speaker 1: for the cosmic microwave background radiation, Like if you look left, 311 00:16:39,640 --> 00:16:42,080 Speaker 1: you'll be looking at a different part of the early universe, 312 00:16:42,080 --> 00:16:44,120 Speaker 1: and if you look right. But I guess the question 313 00:16:44,160 --> 00:16:46,720 Speaker 1: is if I look in one particular direction and I 314 00:16:46,800 --> 00:16:49,920 Speaker 1: keep looking there, am I getting the photons from the 315 00:16:49,960 --> 00:16:52,240 Speaker 1: same spot of the universe or is it kind of 316 00:16:52,280 --> 00:16:55,320 Speaker 1: like an observable universe thing where you know, I'm looking 317 00:16:55,360 --> 00:16:58,160 Speaker 1: at photons from the early universe further and further out 318 00:16:58,160 --> 00:17:00,360 Speaker 1: the longer I look. Yeah, you're looking for further and 319 00:17:00,360 --> 00:17:02,920 Speaker 1: further out the longer you look. So the CMB that 320 00:17:03,000 --> 00:17:06,760 Speaker 1: we see will change as time goes on, because we're 321 00:17:06,800 --> 00:17:09,400 Speaker 1: essentially looking at it from a larger and larger sphere 322 00:17:09,600 --> 00:17:11,399 Speaker 1: I see. So we're sort of getting a three D 323 00:17:11,560 --> 00:17:14,840 Speaker 1: picture almost the universe, yes, exactly, because it's not a 324 00:17:14,880 --> 00:17:17,560 Speaker 1: continuous source in time the way a star is. Right, 325 00:17:17,560 --> 00:17:19,480 Speaker 1: when you look at a star, you're seeing the star 326 00:17:19,520 --> 00:17:22,520 Speaker 1: where it is, and it's continuing to beam photons at 327 00:17:22,560 --> 00:17:24,440 Speaker 1: you every second, and so as you look at it, 328 00:17:24,480 --> 00:17:27,439 Speaker 1: you see new photons. But the CMB was generated in 329 00:17:27,560 --> 00:17:30,480 Speaker 1: one moment. It's one moment in time, and so when 330 00:17:30,480 --> 00:17:33,000 Speaker 1: you look out at the same b right now, you're 331 00:17:33,000 --> 00:17:35,560 Speaker 1: seeing like a shell around the Earth, and then ten 332 00:17:35,600 --> 00:17:38,639 Speaker 1: seconds later you see the c MB from a larger shell, 333 00:17:38,760 --> 00:17:42,720 Speaker 1: ten light seconds larger than the previous one. And it's 334 00:17:42,760 --> 00:17:45,240 Speaker 1: a wiggling in time, like is it sort of changing 335 00:17:45,280 --> 00:17:48,760 Speaker 1: in volume as well as in direction. There are some wiggles. 336 00:17:48,800 --> 00:17:51,080 Speaker 1: I mean, it's pretty faint and we've only been observing 337 00:17:51,119 --> 00:17:53,240 Speaker 1: it for a few years, so we don't expect to 338 00:17:53,280 --> 00:17:57,760 Speaker 1: see like variations on that kind of time scale. Al right, 339 00:17:57,800 --> 00:18:01,080 Speaker 1: So that microwave radiation tells is it's like a picture 340 00:18:01,119 --> 00:18:03,520 Speaker 1: of that early universe when it sort of crystallized and 341 00:18:03,560 --> 00:18:07,000 Speaker 1: cool down, and the mysteries that are hot and cold 342 00:18:07,040 --> 00:18:08,639 Speaker 1: spots on it, right, Like if you look at the 343 00:18:08,640 --> 00:18:11,920 Speaker 1: temperature of that radiation, it's not even so here physicists 344 00:18:11,920 --> 00:18:14,119 Speaker 1: are sort of playing a little game. They're saying, those 345 00:18:14,119 --> 00:18:18,120 Speaker 1: photons themselves don't have a temperature. We're talking about the 346 00:18:18,160 --> 00:18:21,360 Speaker 1: heat of the thing that made the photons. And there's 347 00:18:21,400 --> 00:18:24,399 Speaker 1: this concept in physics, this connection between the frequency of 348 00:18:24,480 --> 00:18:27,320 Speaker 1: light you generate and the temperature you have. And it's 349 00:18:27,320 --> 00:18:29,760 Speaker 1: pretty simple when you think about it. Hot things tend 350 00:18:29,840 --> 00:18:32,679 Speaker 1: to glow, and as they get hotter, they glow in 351 00:18:32,800 --> 00:18:36,119 Speaker 1: higher frequencies, like everything around you is actually glowing in 352 00:18:36,280 --> 00:18:40,000 Speaker 1: very low frequencies. You're giving off infrared radiation right now. 353 00:18:40,160 --> 00:18:42,320 Speaker 1: If you heat it up your body really really hot, 354 00:18:42,480 --> 00:18:45,840 Speaker 1: not recommended the thousands of degrees, you would glow red, 355 00:18:45,960 --> 00:18:47,760 Speaker 1: or you would glow blue, or you would glow white. 356 00:18:47,880 --> 00:18:50,560 Speaker 1: That's why the Sun, for example, glows more than the 357 00:18:50,600 --> 00:18:52,640 Speaker 1: Earth because it's much much hotter. So when we talk 358 00:18:52,720 --> 00:18:55,679 Speaker 1: about the temperature of the CMB, we really mean the 359 00:18:55,720 --> 00:18:58,040 Speaker 1: temperature of a thing that would give off light at 360 00:18:58,080 --> 00:19:01,719 Speaker 1: that frequency. So when you tell your spouse that they 361 00:19:01,720 --> 00:19:04,560 Speaker 1: have a special glow about them, really you're just saying 362 00:19:04,560 --> 00:19:08,440 Speaker 1: that they glow like everything else exactly. But if they're 363 00:19:08,440 --> 00:19:13,760 Speaker 1: extra hot, then maybe they are radioactive, or maybe they're 364 00:19:13,840 --> 00:19:17,119 Speaker 1: just glowing red and angry at you or something. And 365 00:19:17,160 --> 00:19:19,399 Speaker 1: so when we look at like the temperature of the 366 00:19:19,400 --> 00:19:22,720 Speaker 1: CNB really means the wavelength of the CNB, and if 367 00:19:22,760 --> 00:19:25,480 Speaker 1: something is hotter, then it's a little bit more blue shifted. 368 00:19:25,520 --> 00:19:28,520 Speaker 1: If something is colder, it's a little bit more red shifted. Right, 369 00:19:28,520 --> 00:19:30,600 Speaker 1: But it tells you, basically, at the end of the day, 370 00:19:30,760 --> 00:19:34,280 Speaker 1: how hot or how cold that early universe was in 371 00:19:34,400 --> 00:19:37,200 Speaker 1: different directions. Yeah, it does. It can't tell you that now. 372 00:19:37,240 --> 00:19:39,440 Speaker 1: The temperature that we measure is sort of a crazy, 373 00:19:39,480 --> 00:19:43,400 Speaker 1: crazy low temperature. It's like two point seven degrees kelvin, 374 00:19:43,560 --> 00:19:46,720 Speaker 1: which is like just above absolute zero. Right, it's really 375 00:19:46,760 --> 00:19:49,639 Speaker 1: really cold. And that seems confusing because we're saying that 376 00:19:49,680 --> 00:19:52,480 Speaker 1: the universe was really really hot, right it was like 377 00:19:52,520 --> 00:19:54,919 Speaker 1: a hot burning plasma. Well it was. It was like 378 00:19:55,040 --> 00:19:58,439 Speaker 1: three thousand degrees kelvin when this light was made. But 379 00:19:58,480 --> 00:20:01,119 Speaker 1: the light has gotten red shift over time because the 380 00:20:01,240 --> 00:20:05,040 Speaker 1: universe is expanding and that stretches out that light lengthens 381 00:20:05,080 --> 00:20:08,760 Speaker 1: its wavelength and lowers its effective temperature. Right, all right, Well, 382 00:20:08,800 --> 00:20:11,520 Speaker 1: so then we're noticing that it has cold spots and 383 00:20:11,640 --> 00:20:16,120 Speaker 1: temperature that radiation, and so there are hot and cold spots. 384 00:20:16,160 --> 00:20:18,679 Speaker 1: So let's talk about what that big cold spot is 385 00:20:18,760 --> 00:20:21,159 Speaker 1: and what it could mean. But first let's take a 386 00:20:21,200 --> 00:20:35,480 Speaker 1: quick break, all right, Daniel. We're trying to cure the 387 00:20:35,560 --> 00:20:40,080 Speaker 1: universe of its cold sore. The universe is going on 388 00:20:40,119 --> 00:20:43,359 Speaker 1: a date and it wants to look hot. Yeah, or 389 00:20:43,400 --> 00:20:44,960 Speaker 1: to figure out if we live in a hot spot. 390 00:20:45,600 --> 00:20:48,520 Speaker 1: It's pretty happening around here and on Earth. But who knows, 391 00:20:48,560 --> 00:20:50,520 Speaker 1: Maybe we're we're in the cold spot, or maybe our 392 00:20:50,560 --> 00:20:53,240 Speaker 1: whole universe is not that hot out there in the multiverse. 393 00:20:53,280 --> 00:20:56,119 Speaker 1: Maybe there are much hotter universes. Oh man, See now 394 00:20:56,160 --> 00:20:58,120 Speaker 1: you're just playing that game. You're saying that the light 395 00:20:58,200 --> 00:21:00,920 Speaker 1: is greener on the other side of the multiverse. I'm 396 00:21:00,960 --> 00:21:02,720 Speaker 1: just saying, you know, maybe our universe should get on 397 00:21:02,840 --> 00:21:06,119 Speaker 1: universe tinder and consider its options. It might choose a 398 00:21:06,160 --> 00:21:10,840 Speaker 1: different you here hoping for or worried about. No, I'm 399 00:21:10,840 --> 00:21:13,119 Speaker 1: just saying, you know, hey, get some quantum entanglement going on, 400 00:21:13,200 --> 00:21:15,920 Speaker 1: we can get some information from another universe. Boy, Now 401 00:21:15,920 --> 00:21:19,159 Speaker 1: you sound like a Marvel movie. Dan. All right, so 402 00:21:19,200 --> 00:21:22,719 Speaker 1: there's a cosmic microwave background radiation it's coming at us 403 00:21:22,760 --> 00:21:26,280 Speaker 1: from all directions, and it's telling us about the early universe, 404 00:21:26,480 --> 00:21:28,639 Speaker 1: and there are cold spots in it. So tell me 405 00:21:28,680 --> 00:21:32,120 Speaker 1: about these cold spots. And apparently there's one big cold spot. Yeah. 406 00:21:32,119 --> 00:21:34,640 Speaker 1: So when they first found this radiation, it was really 407 00:21:34,680 --> 00:21:37,320 Speaker 1: exciting because it was essentially proof that the universe had 408 00:21:37,400 --> 00:21:40,440 Speaker 1: once been plasma. That was really cool. And they looked 409 00:21:40,440 --> 00:21:42,439 Speaker 1: at it and it was pretty smooth at first, like 410 00:21:42,760 --> 00:21:45,760 Speaker 1: it's basically the same temperature everywhere. But then they made 411 00:21:45,840 --> 00:21:48,640 Speaker 1: better and better measurements of it and they found these wiggles. 412 00:21:48,640 --> 00:21:51,199 Speaker 1: They found these hot spots and these cold spots, and 413 00:21:51,240 --> 00:21:55,240 Speaker 1: these are actually really really small wiggles, like we're talking 414 00:21:55,359 --> 00:21:59,199 Speaker 1: about twenty microkelvin's or so, like one factor in a 415 00:21:59,320 --> 00:22:03,320 Speaker 1: hundred thousand. So it's almost exactly smooth, but there are 416 00:22:03,400 --> 00:22:07,480 Speaker 1: these little variations in temperature, kind of like a texture 417 00:22:07,520 --> 00:22:10,080 Speaker 1: almost to the light. Yeah, kind of like a texture. 418 00:22:10,359 --> 00:22:12,119 Speaker 1: And you might think, oh, well, that's just nothing, but 419 00:22:12,160 --> 00:22:15,400 Speaker 1: there are statistically significant, like we've measured enough of these 420 00:22:15,400 --> 00:22:17,760 Speaker 1: photons to tell that it's a real effect. It's not 421 00:22:17,800 --> 00:22:20,520 Speaker 1: just like noise in the data. It's fascinating because those 422 00:22:20,560 --> 00:22:23,760 Speaker 1: little wiggles tell us about wiggles in the early universe, 423 00:22:23,840 --> 00:22:27,600 Speaker 1: which revel really interesting and important facts about the nature 424 00:22:27,640 --> 00:22:30,479 Speaker 1: of the universe itself. And they're pretty consistent, I imagine, right, 425 00:22:30,840 --> 00:22:33,160 Speaker 1: Like if you take a picture of the microwave cosmic 426 00:22:33,200 --> 00:22:36,080 Speaker 1: background now and I take another picture of it later, 427 00:22:36,200 --> 00:22:39,400 Speaker 1: you'll see the same wiggles, Like the wiggles won't go away. Yeah, exactly. 428 00:22:39,440 --> 00:22:42,720 Speaker 1: These come from wiggles in the original plasma, and so 429 00:22:42,840 --> 00:22:45,639 Speaker 1: we're seeing those exactly, they're still there. Yeah. Like if 430 00:22:45,680 --> 00:22:47,800 Speaker 1: you point your antenna at one spot in the sky, 431 00:22:48,119 --> 00:22:52,000 Speaker 1: you'll get consistently a little cooler measurement there, right, or 432 00:22:52,000 --> 00:22:55,280 Speaker 1: a hotter exactly. And you need a really really refined 433 00:22:55,359 --> 00:22:57,399 Speaker 1: measurement in order to even see this, because it's like 434 00:22:57,440 --> 00:22:59,760 Speaker 1: one part in a hundred thousand. You need a very 435 00:22:59,840 --> 00:23:03,000 Speaker 1: very find instrument to capture that, right. And So what 436 00:23:03,200 --> 00:23:06,439 Speaker 1: causes these variations in the temperature of the universe, Like 437 00:23:06,480 --> 00:23:09,880 Speaker 1: why is it colder or hotter in some places than others? Yeah, 438 00:23:09,920 --> 00:23:14,000 Speaker 1: it's fascinating. There are two main reasons. One is that 439 00:23:14,080 --> 00:23:16,840 Speaker 1: there just were hot spots and cold spots like in 440 00:23:16,880 --> 00:23:21,080 Speaker 1: the original plasma. Quantum fluctuations. You know, you might imagine 441 00:23:21,160 --> 00:23:24,520 Speaker 1: the universe starting sort of like smoothly, like homogeneously, like 442 00:23:24,600 --> 00:23:27,240 Speaker 1: every place in the universe when he was born. However 443 00:23:27,280 --> 00:23:29,800 Speaker 1: that happened was the same. So then how do you 444 00:23:29,840 --> 00:23:32,479 Speaker 1: go from that to like having a star here and 445 00:23:32,560 --> 00:23:35,920 Speaker 1: not having a star there. Well, that has to begin somewhere, 446 00:23:36,240 --> 00:23:39,240 Speaker 1: and we think that quantum fluctuations in the very very 447 00:23:39,280 --> 00:23:42,959 Speaker 1: early original universe, well before this plasma then got like 448 00:23:43,119 --> 00:23:47,280 Speaker 1: blown up by cosmic inflation, this process where you take 449 00:23:47,320 --> 00:23:49,800 Speaker 1: the universe and you expanded by like ten to the 450 00:23:50,000 --> 00:23:53,320 Speaker 1: thirty intend of the minus thirty seconds. So you get 451 00:23:53,359 --> 00:23:56,240 Speaker 1: these random quantum wiggles in the very early universe which 452 00:23:56,280 --> 00:24:01,000 Speaker 1: then get blown up into macroscopic wiggles in a real universe, 453 00:24:01,160 --> 00:24:03,640 Speaker 1: which lead to like little hot spots and little cold 454 00:24:03,640 --> 00:24:07,280 Speaker 1: spots in this original plasma. Mm hmmm. That's because the 455 00:24:07,320 --> 00:24:09,880 Speaker 1: early universe was so small, right, Like, it was so 456 00:24:09,920 --> 00:24:12,600 Speaker 1: small and so compact, and everything was crunched together so 457 00:24:12,680 --> 00:24:16,960 Speaker 1: much that the quantum uncertainty of this quirk or this 458 00:24:17,119 --> 00:24:20,520 Speaker 1: particle made a big difference. It's hard to talk about 459 00:24:20,560 --> 00:24:23,159 Speaker 1: the original universe as small, because I think it was 460 00:24:23,200 --> 00:24:25,840 Speaker 1: always infinite, and so we had an infinite universe which 461 00:24:25,920 --> 00:24:30,080 Speaker 1: then got like expanded massively to an infinite universe, and 462 00:24:30,119 --> 00:24:31,879 Speaker 1: you know, it's harder to think about it as bigger 463 00:24:32,119 --> 00:24:35,520 Speaker 1: or smaller. Some like subtle mathematics, they're like, are there 464 00:24:35,560 --> 00:24:38,639 Speaker 1: more numbers between zero and one than they're between zero 465 00:24:38,720 --> 00:24:43,440 Speaker 1: and ten? There aren't. Actually, there's no one to one 466 00:24:43,480 --> 00:24:45,960 Speaker 1: mapping between those two things. So the universe is like 467 00:24:46,080 --> 00:24:49,280 Speaker 1: technically the same size even though it expanded. That's a 468 00:24:49,320 --> 00:24:52,600 Speaker 1: whole other mind bending discussion. But you're exactly right, little 469 00:24:52,680 --> 00:24:56,159 Speaker 1: like quirk to quirk fluctuations, little quantum randomness. Right, The 470 00:24:56,200 --> 00:24:59,120 Speaker 1: only way something can happen differently in one spot than 471 00:24:59,200 --> 00:25:01,920 Speaker 1: in another if of the same initial conditions is through 472 00:25:02,000 --> 00:25:05,679 Speaker 1: quantum mechanics. It's the only source of actual randomness. Usually 473 00:25:05,720 --> 00:25:07,919 Speaker 1: we don't notice that it doesn't affect anything, But if 474 00:25:07,960 --> 00:25:11,119 Speaker 1: all of a sudden, random quantum fluctuations get blown up 475 00:25:11,119 --> 00:25:14,560 Speaker 1: to the macroscopic size by inflation, then it does matter 476 00:25:14,800 --> 00:25:16,719 Speaker 1: that it can have a real impact on the shape 477 00:25:16,720 --> 00:25:18,639 Speaker 1: of the universe. Right. It's sort of like when you 478 00:25:18,760 --> 00:25:21,040 Speaker 1: zoom in on a picture on your phone or a 479 00:25:21,040 --> 00:25:23,120 Speaker 1: computer screen, Like you blow it up, but you can 480 00:25:23,160 --> 00:25:25,800 Speaker 1: see all the imperfections in it, right, And then we 481 00:25:25,840 --> 00:25:28,719 Speaker 1: can actually do some really amazing physics. We can model 482 00:25:28,760 --> 00:25:31,240 Speaker 1: that plasma. We can say, well, that plasma was probably 483 00:25:31,320 --> 00:25:34,520 Speaker 1: some percentage dark matter and some percentage quirks, and some 484 00:25:34,560 --> 00:25:38,120 Speaker 1: percentage light, and we understand how those things like attract 485 00:25:38,160 --> 00:25:40,560 Speaker 1: each other and bounce off each other. So people have 486 00:25:40,640 --> 00:25:45,640 Speaker 1: done incredibly detailed studies of like the acoustic oscillations of 487 00:25:45,680 --> 00:25:49,720 Speaker 1: that plasma, understanding how those things are bouncing against each other, 488 00:25:49,840 --> 00:25:53,440 Speaker 1: and measuring from that plasma how much dark matter there 489 00:25:53,640 --> 00:25:57,520 Speaker 1: was in the universe, because dark matter and quarks interact 490 00:25:57,600 --> 00:26:00,560 Speaker 1: very differently, so they change the shape of those oscillations 491 00:26:00,720 --> 00:26:03,000 Speaker 1: in that original plasma. Right. That's one of the ways 492 00:26:03,040 --> 00:26:05,840 Speaker 1: we know that dark matter exists in that it exists 493 00:26:05,840 --> 00:26:08,320 Speaker 1: at a certain percentage of the universe is because it 494 00:26:08,440 --> 00:26:11,600 Speaker 1: cosmic microrade background radiation tells you how much dark matter 495 00:26:11,680 --> 00:26:14,160 Speaker 1: there was and is in the universe exactly. And it's 496 00:26:14,200 --> 00:26:16,520 Speaker 1: those hot spots and cold spots that tell you, like, 497 00:26:16,640 --> 00:26:19,080 Speaker 1: if there was more dark matter, then you would have 498 00:26:19,160 --> 00:26:22,600 Speaker 1: different kinds of wiggles and oscillations in that original plasma, 499 00:26:22,720 --> 00:26:25,359 Speaker 1: and then you would see a different pattern of hot 500 00:26:25,359 --> 00:26:28,640 Speaker 1: spots and cold spots in the CNB today. So that's 501 00:26:28,720 --> 00:26:30,720 Speaker 1: one source of the hot spots and cold spots, like 502 00:26:30,760 --> 00:26:34,800 Speaker 1: the original primordial plasma itself was hotter or colder. But 503 00:26:34,800 --> 00:26:38,240 Speaker 1: then there's another super fascinating, really interesting way that this 504 00:26:38,359 --> 00:26:40,560 Speaker 1: light can get hotter and colder. What is it? Well, 505 00:26:40,600 --> 00:26:42,879 Speaker 1: it turns out that as this light flies through the 506 00:26:42,960 --> 00:26:46,720 Speaker 1: universe to us, it basically measures how much matter is 507 00:26:46,760 --> 00:26:49,720 Speaker 1: along the way. If that light passes through really dense 508 00:26:49,840 --> 00:26:52,280 Speaker 1: regions of the sky, it picks up some energy and 509 00:26:52,320 --> 00:26:54,880 Speaker 1: it gets bluer. If the light passes through like really 510 00:26:54,920 --> 00:26:57,760 Speaker 1: really empty regions of the sky, then it loses some 511 00:26:57,840 --> 00:27:00,640 Speaker 1: of its energy as it leaves like the obviously more 512 00:27:00,680 --> 00:27:03,679 Speaker 1: dense region, and it gets redder. So some of the 513 00:27:03,720 --> 00:27:06,560 Speaker 1: red and blue shifts in the CNB, the hot and 514 00:27:06,600 --> 00:27:10,280 Speaker 1: cold spots come from differences and how much stuff there 515 00:27:10,440 --> 00:27:13,560 Speaker 1: is now between us and where the lights started. So 516 00:27:13,680 --> 00:27:16,480 Speaker 1: sort of like measuring the density of the universe along 517 00:27:16,480 --> 00:27:19,640 Speaker 1: the line right, interesting, So can you tell the difference 518 00:27:19,680 --> 00:27:23,840 Speaker 1: like how much a variation in the radiation is due 519 00:27:23,880 --> 00:27:28,600 Speaker 1: to its original fluctuations or it's present fluctuations. Can you 520 00:27:28,640 --> 00:27:30,520 Speaker 1: tell the difference? Yeah, we can. We think that make 521 00:27:30,640 --> 00:27:34,400 Speaker 1: very different sort of scale effects like these variations due 522 00:27:34,400 --> 00:27:38,000 Speaker 1: to structure and density make very large scale effects that 523 00:27:38,040 --> 00:27:40,360 Speaker 1: have like effects of the size of like ten degrees 524 00:27:40,440 --> 00:27:43,359 Speaker 1: on the sky, whereas the other ones that indicate like 525 00:27:43,440 --> 00:27:45,960 Speaker 1: you know, the very on acoustic ostillations and the fraction 526 00:27:46,000 --> 00:27:48,760 Speaker 1: of dark matter make much smaller effects. And so it's 527 00:27:48,800 --> 00:27:52,080 Speaker 1: fascinating because you can sort of like pull apart this information. 528 00:27:52,119 --> 00:27:55,160 Speaker 1: You can learn very different things about the universe, what's 529 00:27:55,200 --> 00:27:58,080 Speaker 1: going on today, the density of stuff, and what happened 530 00:27:58,160 --> 00:28:00,919 Speaker 1: the very early universe by studying the hot spots and 531 00:28:00,960 --> 00:28:04,560 Speaker 1: cold spots at different scales. All right, Well, for the 532 00:28:04,600 --> 00:28:08,199 Speaker 1: most part, these variations in the cosmic microwave background are 533 00:28:08,400 --> 00:28:10,280 Speaker 1: sort of small, right, Like, if you look at a 534 00:28:10,320 --> 00:28:13,119 Speaker 1: picture of the cosmic microwave background radiation, it sort of 535 00:28:13,119 --> 00:28:17,080 Speaker 1: looks like almost television noise, right for the most part, Yeah, exactly, 536 00:28:17,359 --> 00:28:20,399 Speaker 1: it's pretty smooth. Like you look around the CMB and 537 00:28:20,440 --> 00:28:24,600 Speaker 1: you see typically variations of about you know, twenty microkelvin's, 538 00:28:24,640 --> 00:28:26,480 Speaker 1: and they tend to be like, you know, about one 539 00:28:26,560 --> 00:28:30,320 Speaker 1: angular degree. Sometimes there are larger effects because like we're 540 00:28:30,320 --> 00:28:32,800 Speaker 1: moving through the rest frame of this radiation, et cetera. 541 00:28:33,040 --> 00:28:36,720 Speaker 1: But typically we see like you know, twenty microkelvin's about 542 00:28:36,760 --> 00:28:39,560 Speaker 1: one angular degree, and that's about what you expect. You know, 543 00:28:39,640 --> 00:28:42,600 Speaker 1: you expect some variation, some hot or some cold, or 544 00:28:42,640 --> 00:28:44,600 Speaker 1: some a little cold or some a little hotter. But 545 00:28:44,680 --> 00:28:47,000 Speaker 1: we expected to follow like a pretty nice and tidy 546 00:28:47,040 --> 00:28:49,480 Speaker 1: statistical distribution. Yeah, like I was saying, it sort of 547 00:28:49,520 --> 00:28:52,600 Speaker 1: looks like television noise. But if you look in some spots, though, 548 00:28:52,760 --> 00:28:56,440 Speaker 1: you do see kind of bigger features in this noise, right, 549 00:28:56,480 --> 00:28:59,680 Speaker 1: almost like some ghostly features in your TV static. Yeah, 550 00:28:59,720 --> 00:29:04,000 Speaker 1: there's one spot has astrophysicists and cosmologists puzzling for like 551 00:29:04,080 --> 00:29:07,040 Speaker 1: more than a decade, and it's called the cold spot, 552 00:29:07,280 --> 00:29:10,000 Speaker 1: and it's a spot in the sky where this radiation 553 00:29:10,120 --> 00:29:13,800 Speaker 1: is surprisingly cold. It's much colder than it is anywhere else, 554 00:29:14,160 --> 00:29:16,800 Speaker 1: and it's a much bigger spot than you expect to see. 555 00:29:16,920 --> 00:29:18,920 Speaker 1: So this thing is like seventy or up to a 556 00:29:19,000 --> 00:29:23,920 Speaker 1: hundred and fifty microkelvin's colder than the average CNB temperature, 557 00:29:24,240 --> 00:29:27,480 Speaker 1: and it's like five angular degrees. So you can see 558 00:29:27,480 --> 00:29:29,840 Speaker 1: this thing with your eye, like, what, oh, not what 559 00:29:29,880 --> 00:29:33,200 Speaker 1: you like? If you see the picture of the costming 560 00:29:33,240 --> 00:29:35,600 Speaker 1: microwave background, Yeah, that's right. You can't see the CNB 561 00:29:35,680 --> 00:29:38,120 Speaker 1: with your eye, right, it's in microwave frequencies, though I 562 00:29:38,160 --> 00:29:40,400 Speaker 1: guess it does gently cook your food. But you can't 563 00:29:40,440 --> 00:29:42,080 Speaker 1: see it with your eye. But if you look at 564 00:29:42,120 --> 00:29:45,240 Speaker 1: a plot of this stuff you see this spot, you're like, oh, 565 00:29:45,280 --> 00:29:47,840 Speaker 1: there's an extra dark blue spot there where you might 566 00:29:47,840 --> 00:29:50,680 Speaker 1: not otherwise expect it. M M. Now is that a 567 00:29:50,680 --> 00:29:53,680 Speaker 1: lot of five angular degrees? How big in the sky 568 00:29:53,840 --> 00:29:55,560 Speaker 1: are we talking about? Like the size of the sun 569 00:29:55,600 --> 00:29:58,000 Speaker 1: as we will see it, or the moon or of 570 00:29:58,080 --> 00:30:01,320 Speaker 1: texas well, the moon is about half a degree in 571 00:30:01,320 --> 00:30:03,880 Speaker 1: the sky, and so yeah, this is a pretty big 572 00:30:03,920 --> 00:30:06,400 Speaker 1: effect I see. So like if you lived to look out, 573 00:30:06,440 --> 00:30:09,120 Speaker 1: you would see like something ten times larger than the moon. 574 00:30:09,360 --> 00:30:11,960 Speaker 1: And that's how big this could spot is, yeah, exactly. 575 00:30:12,240 --> 00:30:14,720 Speaker 1: And it's in the southern hemisphere. So you looked in 576 00:30:14,760 --> 00:30:18,880 Speaker 1: the direction of the constellation Irridanus, then that's the direction 577 00:30:19,080 --> 00:30:23,400 Speaker 1: from which this light is extra cold. All right, So 578 00:30:23,440 --> 00:30:25,600 Speaker 1: that there's a big cold spot in the sky, that 579 00:30:25,760 --> 00:30:27,840 Speaker 1: my may tell us that the universe had a big 580 00:30:27,840 --> 00:30:30,840 Speaker 1: cold spot when it was born. Maybe, So let's dig 581 00:30:30,920 --> 00:30:33,120 Speaker 1: into that and let's talk about what it could mean. 582 00:30:33,440 --> 00:30:48,080 Speaker 1: But first let's take another quick break, all right, the 583 00:30:48,360 --> 00:30:51,960 Speaker 1: early universe had a cold spot, Daniel, possibly at least 584 00:30:51,960 --> 00:30:53,600 Speaker 1: from what we can see right now. If we look 585 00:30:53,600 --> 00:30:56,720 Speaker 1: out into the sky at the cosmic microwave background radiation, 586 00:30:56,880 --> 00:31:00,160 Speaker 1: we see that there's one spot that is cold are 587 00:31:00,200 --> 00:31:02,760 Speaker 1: than the rest of the universe. So what's going on? Yeah, 588 00:31:02,800 --> 00:31:05,440 Speaker 1: it's a big cold spot. And you know, we can 589 00:31:05,480 --> 00:31:09,360 Speaker 1: never really definitively no, because there are a few possible 590 00:31:09,440 --> 00:31:13,280 Speaker 1: explanations and they range from like the total yawn fast 591 00:31:13,360 --> 00:31:17,560 Speaker 1: boring explanation to like the crazy, mind blowing revealing the 592 00:31:17,640 --> 00:31:20,680 Speaker 1: nature of reality kind of explanation. I mean, I guess 593 00:31:20,720 --> 00:31:23,640 Speaker 1: which one you're hoping for, Not the boring one. I'm 594 00:31:23,680 --> 00:31:26,920 Speaker 1: hoping for aliens. But there's no alien explanation for this one, 595 00:31:28,880 --> 00:31:31,880 Speaker 1: not yet. But we still got fifteen minutes on this podcast. Well, 596 00:31:31,920 --> 00:31:34,320 Speaker 1: we'll figure something out for you, or when we write 597 00:31:34,320 --> 00:31:39,480 Speaker 1: our pitch script to Marvel, will include aliens somehow. Oh yeah, 598 00:31:39,600 --> 00:31:44,360 Speaker 1: microwave guardians of the universe, Guardians of the micro universe. 599 00:31:44,600 --> 00:31:47,120 Speaker 1: All right, So what are these possible explanations for this 600 00:31:47,400 --> 00:31:49,720 Speaker 1: cold spot? Now? I know we see it out there 601 00:31:49,720 --> 00:31:52,720 Speaker 1: in the microwave radiation, but do we think that it's 602 00:31:52,800 --> 00:31:55,120 Speaker 1: like a hole through the universe or like a sphere 603 00:31:55,200 --> 00:31:57,760 Speaker 1: out there of coldness what we think it looks like. 604 00:31:58,000 --> 00:32:02,120 Speaker 1: Well there really there are two ethic explanations. One is 605 00:32:02,160 --> 00:32:05,760 Speaker 1: that like the light was generated itself from a colder 606 00:32:05,880 --> 00:32:09,080 Speaker 1: spot in the original plasma. And you know, we're talking 607 00:32:09,080 --> 00:32:13,000 Speaker 1: about quantum effects here, and quantumness is random, and sometimes 608 00:32:13,160 --> 00:32:15,520 Speaker 1: randomness gives you weird stuff. You know, if you flip 609 00:32:15,560 --> 00:32:18,840 Speaker 1: a coin ten times, you do have a chance, however small, 610 00:32:18,920 --> 00:32:21,240 Speaker 1: to get ten heads in a row. It can happen. 611 00:32:21,360 --> 00:32:25,080 Speaker 1: And so one possible explanation is that those original quantum 612 00:32:25,120 --> 00:32:28,520 Speaker 1: fluctuations in the early universe just happened to create a 613 00:32:28,560 --> 00:32:32,200 Speaker 1: spot with less density of stuff, a slightly colder spot 614 00:32:32,480 --> 00:32:36,440 Speaker 1: in the original plasma. Like maybe that that's just how 615 00:32:36,480 --> 00:32:39,160 Speaker 1: the universe rolled, you know, or like that's what they 616 00:32:39,760 --> 00:32:43,440 Speaker 1: got in their role playing character role when it determined 617 00:32:43,480 --> 00:32:46,040 Speaker 1: would look like it just happened to have a cold spot. Yeah, 618 00:32:46,120 --> 00:32:48,680 Speaker 1: it's possibility. That's one explanation. Yeah, it's sort of like 619 00:32:48,720 --> 00:32:51,480 Speaker 1: a non explanation. But you know, every time you have 620 00:32:52,000 --> 00:32:55,200 Speaker 1: random effects and you have a statistical distribution, you never 621 00:32:55,280 --> 00:32:57,920 Speaker 1: really know, and so this is pretty unlikely. We can 622 00:32:58,000 --> 00:33:01,040 Speaker 1: quantify how unlikely it is. We have a model for 623 00:33:01,240 --> 00:33:03,760 Speaker 1: what those quantum fluctuations should have looked like. And just 624 00:33:03,800 --> 00:33:06,040 Speaker 1: like you can calculate how likely is it to get 625 00:33:06,080 --> 00:33:07,960 Speaker 1: ten heads in a row when you flip a coin, 626 00:33:08,280 --> 00:33:10,680 Speaker 1: we can calculate how likely is it to see this 627 00:33:10,800 --> 00:33:13,960 Speaker 1: coldest spot this size in the sky. You know, it's 628 00:33:14,000 --> 00:33:17,240 Speaker 1: like a one in two hundred chants though it's like 629 00:33:17,520 --> 00:33:21,040 Speaker 1: right on the edge there where it seems kind of improbable, 630 00:33:21,080 --> 00:33:23,600 Speaker 1: but it's not impossible. You know, we only have this 631 00:33:23,720 --> 00:33:27,040 Speaker 1: one universe. If we had a bunch of different universes 632 00:33:27,040 --> 00:33:29,240 Speaker 1: and we have a bunch of different CMBs, we could ask, 633 00:33:29,400 --> 00:33:31,160 Speaker 1: how often do you see something like this? Is it 634 00:33:31,240 --> 00:33:34,200 Speaker 1: really wanting two hundred or is there something else going on? Right? 635 00:33:34,320 --> 00:33:36,880 Speaker 1: Like if you had two hundred universes, one of them 636 00:33:36,920 --> 00:33:40,840 Speaker 1: would probably have a cultpot just naturally exactly, yeah, And 637 00:33:40,880 --> 00:33:42,480 Speaker 1: so you never know, like, did we just get a 638 00:33:42,480 --> 00:33:45,440 Speaker 1: weird one? Do we have an odd universe in some way? 639 00:33:45,840 --> 00:33:47,800 Speaker 1: Or do we not have an understanding for how that 640 00:33:47,880 --> 00:33:50,840 Speaker 1: quantum random has happened and something else is going on? 641 00:33:51,680 --> 00:33:53,920 Speaker 1: We really just don't know. So the most boring vanilla 642 00:33:53,960 --> 00:33:56,160 Speaker 1: explanation is, you know, we just happen to get a 643 00:33:56,160 --> 00:34:01,560 Speaker 1: weird universe. The most boring explanation is just oh, well, 644 00:34:02,320 --> 00:34:04,760 Speaker 1: get what you get and you don't complain. And it's 645 00:34:04,800 --> 00:34:06,760 Speaker 1: also sort of boring because it's not really like much 646 00:34:06,800 --> 00:34:08,680 Speaker 1: to follow up on, like, well, it just is what 647 00:34:08,719 --> 00:34:10,839 Speaker 1: it is, like, you know, sometimes you get double zero 648 00:34:10,880 --> 00:34:12,959 Speaker 1: when you spind the wheel, and there's not much else 649 00:34:13,000 --> 00:34:15,080 Speaker 1: to say about it unless you can prove that it 650 00:34:15,160 --> 00:34:18,000 Speaker 1: is controlled by a different probability distribution than the one 651 00:34:18,040 --> 00:34:20,200 Speaker 1: we expected. But if it is just sort of like 652 00:34:20,280 --> 00:34:23,200 Speaker 1: a weird outlier, then hey, you know that happens, all right. 653 00:34:23,280 --> 00:34:26,719 Speaker 1: Well then what's the next more interesting explanation. Well, the 654 00:34:26,719 --> 00:34:30,520 Speaker 1: next more interesting explanation is that the CMB got cold 655 00:34:30,719 --> 00:34:33,680 Speaker 1: as it flew to us. Remember we talked about how 656 00:34:33,719 --> 00:34:36,080 Speaker 1: the light as it comes to us from where it 657 00:34:36,120 --> 00:34:39,879 Speaker 1: was originally generated is affected by how much stuff there 658 00:34:40,080 --> 00:34:43,320 Speaker 1: is in the universe, and so in that sense, looking 659 00:34:43,400 --> 00:34:45,560 Speaker 1: at this light is a way to probe how much 660 00:34:45,600 --> 00:34:48,560 Speaker 1: stuff there is between us and that original plasma. So 661 00:34:48,600 --> 00:34:51,880 Speaker 1: if there's a really big cold spot in the CMB, 662 00:34:52,120 --> 00:34:56,200 Speaker 1: it could mean that there's like a huge void of stuff. 663 00:34:56,239 --> 00:34:59,000 Speaker 1: There's like a huge blob of space between us and 664 00:34:59,040 --> 00:35:02,200 Speaker 1: that original plasma h that just like has nothing in it. 665 00:35:02,680 --> 00:35:05,600 Speaker 1: M M, I see, because like an empty void like 666 00:35:05,640 --> 00:35:09,200 Speaker 1: that would cool the MicroID background radiation. Right exactly as 667 00:35:09,280 --> 00:35:11,680 Speaker 1: the light enters the void, it loses some energy. It's 668 00:35:11,719 --> 00:35:13,640 Speaker 1: going to lose some energy because it's more like stuff 669 00:35:13,719 --> 00:35:16,440 Speaker 1: behind it. And you know, we expect there to be voids, 670 00:35:16,520 --> 00:35:18,920 Speaker 1: like we know that the structure of the universe is 671 00:35:19,000 --> 00:35:23,080 Speaker 1: you start from stars, which form galaxies. Those galaxies form clusters, 672 00:35:23,239 --> 00:35:26,640 Speaker 1: and those clusters themselves form these like walls and these 673 00:35:26,680 --> 00:35:31,360 Speaker 1: filaments and these huge sheets around bubbles around big voids 674 00:35:31,440 --> 00:35:34,720 Speaker 1: in which there is nothing, and those things are pretty big. 675 00:35:34,880 --> 00:35:38,080 Speaker 1: But those voids would not explain this gap like you 676 00:35:38,080 --> 00:35:41,400 Speaker 1: would need a super void, like a void the size 677 00:35:41,400 --> 00:35:45,600 Speaker 1: of five angular degrees basically right, Yeah, like a humongous 678 00:35:45,640 --> 00:35:50,000 Speaker 1: like multi galaxy empty space. Yeah, much bigger than multi galaxy. 679 00:35:50,239 --> 00:35:53,120 Speaker 1: We're talking about something that's like a thousand times the 680 00:35:53,239 --> 00:35:55,920 Speaker 1: volume of the voids. We see. This thing would have 681 00:35:55,960 --> 00:36:00,560 Speaker 1: to be like billions of light years across some rediculously 682 00:36:00,719 --> 00:36:06,080 Speaker 1: unusual spot in the universe that happens to just contain nothing. Yeah, 683 00:36:06,120 --> 00:36:08,080 Speaker 1: I guess the big question would be, then where did 684 00:36:08,080 --> 00:36:11,280 Speaker 1: this void come from, right, Because don't voids come from 685 00:36:11,320 --> 00:36:14,319 Speaker 1: those original quantum fluctuations too? They do come from that 686 00:36:14,400 --> 00:36:16,880 Speaker 1: exactly the way the universe gets its structure as you 687 00:36:16,960 --> 00:36:20,600 Speaker 1: have those fluctuations, which then build on themselves because anything 688 00:36:20,640 --> 00:36:22,759 Speaker 1: that has a little bit more density, that has a 689 00:36:22,800 --> 00:36:25,520 Speaker 1: little bit more gravity, and so it's tugging more stuff 690 00:36:25,520 --> 00:36:28,240 Speaker 1: in and then it gets denser and it's a runaway effect, 691 00:36:28,280 --> 00:36:31,160 Speaker 1: and so the matter sends to clump together where there 692 00:36:31,200 --> 00:36:34,200 Speaker 1: were original like over densities, and you tend to get 693 00:36:34,280 --> 00:36:37,120 Speaker 1: voids where there were under densities. But that doesn't explain 694 00:36:37,360 --> 00:36:39,680 Speaker 1: how you got that under density, right, sort of like 695 00:36:39,880 --> 00:36:42,680 Speaker 1: again the same question, how is it possible that we 696 00:36:42,719 --> 00:36:44,319 Speaker 1: look at and we see a bunch of voids of 697 00:36:44,320 --> 00:36:47,880 Speaker 1: a particular size, but then there's one super duper void. 698 00:36:48,200 --> 00:36:50,520 Speaker 1: How did that happen? Right? And it goes back to 699 00:36:50,560 --> 00:36:53,240 Speaker 1: the same question almost right, like was there a big 700 00:36:53,360 --> 00:36:56,800 Speaker 1: cold spot like that in the early plasma of the universe. 701 00:36:56,840 --> 00:36:59,040 Speaker 1: It's almost the same question, isn't it. Yeah, it's almost 702 00:36:59,080 --> 00:37:01,560 Speaker 1: the same question, but one would be even bigger. Right, 703 00:37:01,800 --> 00:37:04,560 Speaker 1: In order to create this sort of cold spot, you 704 00:37:04,680 --> 00:37:08,040 Speaker 1: need a really really massive void that would extend across 705 00:37:08,080 --> 00:37:10,959 Speaker 1: a much bigger region of the universe. Such a void 706 00:37:11,040 --> 00:37:13,280 Speaker 1: is like it's hard to gell with, Like our ideas 707 00:37:13,320 --> 00:37:16,279 Speaker 1: about dark matter and dark energy, you just don't get 708 00:37:16,320 --> 00:37:18,719 Speaker 1: this kind of thing. We've run lots of simulations of 709 00:37:18,840 --> 00:37:21,280 Speaker 1: universe is and you never see this kind of structure. 710 00:37:22,160 --> 00:37:24,680 Speaker 1: So this is maybe even more unlikely, but it would 711 00:37:24,719 --> 00:37:28,560 Speaker 1: be more awesome for that reason. I guess the less 712 00:37:28,600 --> 00:37:33,320 Speaker 1: likely it is, the more interesting it is scientifically to right, Yes, exactly, 713 00:37:33,560 --> 00:37:36,120 Speaker 1: we want to see something weird that we can't explain 714 00:37:36,160 --> 00:37:38,400 Speaker 1: with our current theories because that tells us how we 715 00:37:38,480 --> 00:37:41,440 Speaker 1: might be able to change our theories and learn something 716 00:37:41,440 --> 00:37:44,440 Speaker 1: new about the universe. We want to see our theories fail. Right. 717 00:37:44,680 --> 00:37:47,640 Speaker 1: Scientists are not out there like my theory will win out. 718 00:37:47,840 --> 00:37:51,200 Speaker 1: We're trying constantly to disprove our theories because that means 719 00:37:51,239 --> 00:37:54,880 Speaker 1: finding a clue to solving the murder mystery of the universe. 720 00:37:55,600 --> 00:37:57,759 Speaker 1: And so one thing people have done is like, well, 721 00:37:57,840 --> 00:38:00,480 Speaker 1: let's look directly for this void. I mean, if there 722 00:38:00,480 --> 00:38:03,080 Speaker 1: really is a huge gap in stuff out there, we 723 00:38:03,080 --> 00:38:05,719 Speaker 1: could literally see it. Right, this is something we can 724 00:38:05,760 --> 00:38:08,960 Speaker 1: see not just through the CMB, but by directly looking 725 00:38:09,000 --> 00:38:11,839 Speaker 1: to see are there a bunch of galaxies missing, right, 726 00:38:11,920 --> 00:38:14,560 Speaker 1: But we would have to be looking pretty far out, right, 727 00:38:14,640 --> 00:38:16,239 Speaker 1: We would have to be looking pretty far out, but 728 00:38:16,320 --> 00:38:18,880 Speaker 1: we can, right, we can look really far out into 729 00:38:18,920 --> 00:38:21,279 Speaker 1: the universe. This is something which would exist in the 730 00:38:21,360 --> 00:38:25,120 Speaker 1: universe between us and the edge of the observable universe. 731 00:38:25,120 --> 00:38:28,279 Speaker 1: Because remember the CNB comes from almost the edge of 732 00:38:28,320 --> 00:38:31,160 Speaker 1: the observable universe, and so it would have passed through 733 00:38:31,280 --> 00:38:33,640 Speaker 1: this super void. So we should be able to see it. 734 00:38:34,440 --> 00:38:37,320 Speaker 1: And how we've seen it. People looked and seen any 735 00:38:37,360 --> 00:38:41,200 Speaker 1: big empty spaces we have looked, And in two thousand 736 00:38:41,200 --> 00:38:44,440 Speaker 1: and fourteen, a study from University Hawaii actually did find 737 00:38:44,480 --> 00:38:47,759 Speaker 1: a super void, like a really massive void, and they 738 00:38:47,800 --> 00:38:52,399 Speaker 1: called it the largest individual structure identified by humanity, which 739 00:38:52,440 --> 00:38:54,960 Speaker 1: is sort of hilarious because, like I keep seeing that 740 00:38:55,040 --> 00:38:58,160 Speaker 1: in astronomy papers, people keep saying, this is the biggest 741 00:38:58,160 --> 00:39:00,680 Speaker 1: thing in the universe. No, now, this is the biggest 742 00:39:00,719 --> 00:39:03,640 Speaker 1: thing in the universe. It's like they're claim to fame. Yeah, 743 00:39:03,719 --> 00:39:07,720 Speaker 1: but it technically it's the largest empty space they found, right, Yeah, exactly. 744 00:39:07,719 --> 00:39:11,719 Speaker 1: It's like a bubble surrounded by galaxies and galaxy clusters 745 00:39:11,760 --> 00:39:14,359 Speaker 1: with nothing inside it. So they found a really big 746 00:39:14,400 --> 00:39:17,920 Speaker 1: super void roughly in the right direction, but it's not 747 00:39:18,040 --> 00:39:21,200 Speaker 1: actually big enough, and it's not sort of voidy enough, 748 00:39:21,360 --> 00:39:23,840 Speaker 1: like it needs to be like really empty of stuff 749 00:39:23,920 --> 00:39:26,440 Speaker 1: in order to explain this cold shift. And if you 750 00:39:26,520 --> 00:39:28,520 Speaker 1: take this super void and you think, well, what would 751 00:39:28,560 --> 00:39:31,480 Speaker 1: happen to photons passing through it, they don't actually get 752 00:39:31,560 --> 00:39:34,360 Speaker 1: chilled enough to explain the cold spot that we see 753 00:39:34,640 --> 00:39:38,680 Speaker 1: explains like twenty or thirty microkelvins of cooling, not the 754 00:39:38,719 --> 00:39:41,480 Speaker 1: full seventy to a hundred I see. So it's not 755 00:39:41,600 --> 00:39:45,319 Speaker 1: cool enough this super void, this super void is too hot, 756 00:39:45,440 --> 00:39:49,759 Speaker 1: not hot enough or cool enough sadly exactly, even though 757 00:39:49,800 --> 00:39:54,200 Speaker 1: it lives in Hawaii, exactly Hawaiian. So it doesn't really 758 00:39:54,239 --> 00:39:56,920 Speaker 1: match up like you'd love to see, like a massive 759 00:39:56,960 --> 00:39:59,799 Speaker 1: super void just in the same direction that explained. That 760 00:40:00,000 --> 00:40:02,759 Speaker 1: be a really sort of nice connection there, But this one, 761 00:40:02,920 --> 00:40:05,640 Speaker 1: though it's interesting, doesn't actually explain the data. The two 762 00:40:05,680 --> 00:40:08,279 Speaker 1: stories don't really fit together quite well enough. But that's 763 00:40:08,280 --> 00:40:10,360 Speaker 1: just only what we've seen. Like there could still be 764 00:40:10,360 --> 00:40:12,200 Speaker 1: a giant boyd, we just haven't seen it or been 765 00:40:12,239 --> 00:40:14,600 Speaker 1: able to make it out. Yeah, exactly. There's always more 766 00:40:14,600 --> 00:40:17,279 Speaker 1: stuff to look at in better telescopes and new ways 767 00:40:17,320 --> 00:40:19,279 Speaker 1: to analyze the data. But we have not found a 768 00:40:19,320 --> 00:40:23,319 Speaker 1: supervoid out there that explains this cold spot. All right, 769 00:40:23,480 --> 00:40:25,960 Speaker 1: So then what's the craziest idea we have about this 770 00:40:26,160 --> 00:40:29,279 Speaker 1: could spot? The craziest idea about this cold spot is 771 00:40:29,320 --> 00:40:32,640 Speaker 1: that maybe it comes from even earlier in the universe. 772 00:40:32,680 --> 00:40:36,040 Speaker 1: Maybe it comes from the very very birth of our universe. 773 00:40:36,200 --> 00:40:39,200 Speaker 1: People talk about how the universe was made, and one 774 00:40:39,280 --> 00:40:43,200 Speaker 1: possible explanation is that our universe is like a little bubble, 775 00:40:43,360 --> 00:40:47,480 Speaker 1: a bubble of some pre universe stuff that decayed into 776 00:40:47,600 --> 00:40:50,680 Speaker 1: normal matter. And here we are going way out into 777 00:40:50,760 --> 00:40:54,279 Speaker 1: like crazy, no basis speculation for how the universe might 778 00:40:54,320 --> 00:40:57,200 Speaker 1: have been formed, right, no data to support this. But 779 00:40:57,320 --> 00:41:01,000 Speaker 1: it's possible that the universe sort of turn into normal 780 00:41:01,040 --> 00:41:03,880 Speaker 1: matter from some sort of pre universe matter. They call 781 00:41:04,000 --> 00:41:06,960 Speaker 1: this like the Inflaton field. And you have to imagine 782 00:41:07,040 --> 00:41:09,840 Speaker 1: sort of like a meta universe filled with this stuff, 783 00:41:10,040 --> 00:41:13,680 Speaker 1: which then, like birth's individual universes, so like our entire 784 00:41:13,760 --> 00:41:17,920 Speaker 1: universe created in a little bubble inside this larger universe, 785 00:41:19,080 --> 00:41:22,920 Speaker 1: along with other little bubbles exactly along with other little bubbles. 786 00:41:23,040 --> 00:41:25,960 Speaker 1: Where do those bubbles get made? Well, it's quantum mechanical, 787 00:41:26,040 --> 00:41:29,359 Speaker 1: so it's random. And sometimes those bubbles might be really 788 00:41:29,400 --> 00:41:32,680 Speaker 1: close to each other and maybe bump up against each other, 789 00:41:33,239 --> 00:41:35,480 Speaker 1: and if they did that, they might leave a mark 790 00:41:35,680 --> 00:41:38,439 Speaker 1: on each other. You might get like evidence on your 791 00:41:38,520 --> 00:41:42,400 Speaker 1: bubble that you bounced against another bubble. And in some 792 00:41:42,520 --> 00:41:45,760 Speaker 1: of these theories, this effect this sort of like bruise 793 00:41:45,880 --> 00:41:49,240 Speaker 1: on a universe, which show up as a cold spot, 794 00:41:49,560 --> 00:41:52,719 Speaker 1: which would lead to a super void. Wait what you mean, 795 00:41:52,800 --> 00:41:55,600 Speaker 1: like the ideas that these universe are being created in 796 00:41:55,680 --> 00:42:00,520 Speaker 1: this froth of meta universe and sometimes the bubble bumping 797 00:42:00,520 --> 00:42:02,920 Speaker 1: to each other and that would create a cold spot. 798 00:42:02,920 --> 00:42:04,719 Speaker 1: When did it creates like I don't know, like a 799 00:42:04,840 --> 00:42:08,680 Speaker 1: dent maybe more a dent is basically a cold spot. 800 00:42:08,719 --> 00:42:11,600 Speaker 1: You know, it gets like suppressed, It gets like squeezed down, 801 00:42:11,840 --> 00:42:14,799 Speaker 1: and you would expect actually a cold spot surrounded by 802 00:42:14,880 --> 00:42:17,080 Speaker 1: like a little bit of a hot spot. You get 803 00:42:17,120 --> 00:42:20,080 Speaker 1: like a hot ring inside of it a cold spot, 804 00:42:20,280 --> 00:42:22,359 Speaker 1: And that's actually kind of what we see. Like if 805 00:42:22,360 --> 00:42:24,680 Speaker 1: you look at this cold spot, it is cold, but 806 00:42:24,719 --> 00:42:27,400 Speaker 1: the stuff around it is a little bit unusually hot, 807 00:42:27,680 --> 00:42:30,560 Speaker 1: and so it sort of looks like a bruise on 808 00:42:30,680 --> 00:42:34,640 Speaker 1: the cosmic microwave background from a parallel universe. And you know, 809 00:42:34,880 --> 00:42:38,280 Speaker 1: again this is speculation on speculation, on speculation. There are 810 00:42:38,320 --> 00:42:41,360 Speaker 1: many other possible explanations, and we have no evidence that 811 00:42:41,400 --> 00:42:44,600 Speaker 1: there was this meta universe or other bubble universes. But 812 00:42:44,640 --> 00:42:47,600 Speaker 1: it's sort of a fun idea, Like they have a 813 00:42:47,680 --> 00:42:51,280 Speaker 1: model of this crazy multiverse and you can actually model 814 00:42:51,320 --> 00:42:54,120 Speaker 1: like what happens when two universe is bumping to each other. Yeah, 815 00:42:54,160 --> 00:42:56,279 Speaker 1: they do, although you know you have to wonder, like 816 00:42:56,400 --> 00:43:00,239 Speaker 1: are these models designed to explain this cold spot? Is 817 00:43:00,239 --> 00:43:02,920 Speaker 1: not like a prediction. This is sort of like more 818 00:43:03,000 --> 00:43:05,960 Speaker 1: like a post adiction. It's not like fifty years ago 819 00:43:05,960 --> 00:43:08,279 Speaker 1: people are saying we're going to discover the CNB and 820 00:43:08,360 --> 00:43:10,640 Speaker 1: it's going to have a cold spot from the previous universe. 821 00:43:10,680 --> 00:43:13,640 Speaker 1: It's more like a cold spot. I wonder if I 822 00:43:13,680 --> 00:43:17,120 Speaker 1: could explain that using a parallel universe. So here's a 823 00:43:17,200 --> 00:43:19,880 Speaker 1: theory I cooked up, and you probably like tweak the 824 00:43:19,880 --> 00:43:22,799 Speaker 1: parameters until you get the cold spot, right. Yes, that's 825 00:43:22,840 --> 00:43:24,400 Speaker 1: the tricky thing. And so what you got to do 826 00:43:24,480 --> 00:43:27,280 Speaker 1: always when you make a theory that explains the data 827 00:43:27,560 --> 00:43:30,000 Speaker 1: is then you have to predict future data so you 828 00:43:30,000 --> 00:43:34,239 Speaker 1: can test your theory. Otherwise it's just an explanation. Wow. Alright, Well, 829 00:43:34,280 --> 00:43:37,080 Speaker 1: so this big cold spot in the sky in the 830 00:43:37,200 --> 00:43:41,000 Speaker 1: universe background radiation, it sounds like it's still a big mystery, 831 00:43:41,080 --> 00:43:43,680 Speaker 1: like nobody really knows what could be causing it. It's 832 00:43:43,680 --> 00:43:46,200 Speaker 1: still a mystery. It's still something people are puzzling over. 833 00:43:46,360 --> 00:43:49,040 Speaker 1: There even crazier ideas out there that we didn't cover, 834 00:43:49,120 --> 00:43:52,120 Speaker 1: things like cosmic texture and all sorts of weird stuff 835 00:43:52,360 --> 00:43:55,680 Speaker 1: and aliens, aliens. Let's not forget aliens. Here's here's my 836 00:43:55,719 --> 00:43:59,480 Speaker 1: alien theory, Daniel. They build a death star that's billions 837 00:43:59,520 --> 00:44:02,160 Speaker 1: of light year across and that's what's causing the cold spot. 838 00:44:02,640 --> 00:44:08,520 Speaker 1: It's blocking the CNB and it's coming our way. Yeah, 839 00:44:08,600 --> 00:44:10,959 Speaker 1: and there's a one percent chance that I'm totally making 840 00:44:11,000 --> 00:44:14,479 Speaker 1: it up. I love your theory. It sounds just about 841 00:44:14,520 --> 00:44:17,400 Speaker 1: as plausible as the parallel universe theory. Yeah, there you go. 842 00:44:17,560 --> 00:44:19,719 Speaker 1: I am right up there with the leading physicists on 843 00:44:19,760 --> 00:44:22,279 Speaker 1: this matter. Yes, absolutely, you're on the cutting edge. But 844 00:44:22,360 --> 00:44:24,160 Speaker 1: you're right, it could be nothing. It could just be 845 00:44:24,200 --> 00:44:26,880 Speaker 1: like a random quantum fluctuation. But it's not something we 846 00:44:27,120 --> 00:44:30,080 Speaker 1: currently understand, and so it could be that twenty years 847 00:44:30,120 --> 00:44:31,759 Speaker 1: from now we look back and say, oh my gosh, 848 00:44:31,920 --> 00:44:34,600 Speaker 1: that was the clue that told us something deep about 849 00:44:34,600 --> 00:44:38,000 Speaker 1: how the universe works. Because remember, the CNB is filled 850 00:44:38,040 --> 00:44:40,920 Speaker 1: with super rich information about how the universe came to 851 00:44:40,960 --> 00:44:43,000 Speaker 1: be and how it evolved and why it looks the 852 00:44:43,040 --> 00:44:45,480 Speaker 1: way it does today. So I wouldn't be surprised if 853 00:44:45,520 --> 00:44:47,960 Speaker 1: this really, in the end taught us something deep about 854 00:44:47,960 --> 00:44:50,759 Speaker 1: the universe. We just don't know what yet. Yeah, Or 855 00:44:50,800 --> 00:44:52,719 Speaker 1: maybe the universe just doesn't like to talk about it, 856 00:44:52,800 --> 00:44:55,320 Speaker 1: you know, maybe to lit embarrassed by that cold spot, 857 00:44:55,480 --> 00:44:57,480 Speaker 1: in which case maybe we should just look away, Daniel, 858 00:44:57,920 --> 00:45:00,680 Speaker 1: just ignore it. That's the polite thing that don't stare 859 00:45:00,760 --> 00:45:02,760 Speaker 1: that ZiT on your friend's head, and I just pretend 860 00:45:02,800 --> 00:45:06,040 Speaker 1: it's not there. Yeah, Yeah, that's what a good friend 861 00:45:06,080 --> 00:45:08,600 Speaker 1: of the universe would do. All right. Well, again, just 862 00:45:08,640 --> 00:45:11,839 Speaker 1: another reminder that the universe is all around us, it's 863 00:45:11,880 --> 00:45:14,680 Speaker 1: giving us clues all the time, and that there are 864 00:45:14,840 --> 00:45:19,040 Speaker 1: big cold spots of mystery in it, in that information 865 00:45:19,080 --> 00:45:22,920 Speaker 1: that it's bathing as with exactly, they're big giant voids 866 00:45:22,960 --> 00:45:26,480 Speaker 1: of knowledge that we still don't have about the universe. Yep. 867 00:45:26,640 --> 00:45:28,799 Speaker 1: And we have figured out the c MB is there, 868 00:45:28,800 --> 00:45:32,120 Speaker 1: but there's probably other kinds of information that we're swimming 869 00:45:32,120 --> 00:45:35,560 Speaker 1: in right now that contains incredible facts about the origins 870 00:45:35,560 --> 00:45:37,880 Speaker 1: of our universe. We just don't even know how to 871 00:45:37,920 --> 00:45:40,120 Speaker 1: look for it and how to interpret it. In later 872 00:45:40,160 --> 00:45:43,640 Speaker 1: generations will chuckle when they look back at how silly 873 00:45:43,680 --> 00:45:45,920 Speaker 1: and how foolish we were. Right, maybe all we have 874 00:45:46,000 --> 00:45:48,640 Speaker 1: to do is check the cmb R, not the cmb 875 00:45:49,360 --> 00:45:51,840 Speaker 1: and we would have seen the answer. And we should 876 00:45:51,840 --> 00:45:54,400 Speaker 1: have checked the CNBS and the c MBT. I mean, like, 877 00:45:54,480 --> 00:45:56,920 Speaker 1: let's follow up on these things, all the Marvel movies 878 00:45:57,080 --> 00:46:00,080 Speaker 1: right there. All right, Well, we hope you enjoyed the ad. 879 00:46:00,960 --> 00:46:12,080 Speaker 1: Thanks for joining us, see you next time. Thanks for listening, 880 00:46:12,080 --> 00:46:14,800 Speaker 1: and remember that Daniel and Jorge explained the universe is 881 00:46:14,840 --> 00:46:18,239 Speaker 1: a production of I Heart Radio. For more podcast For 882 00:46:18,360 --> 00:46:22,120 Speaker 1: my heart Radio, visit the I heart Radio app, Apple Podcasts, 883 00:46:22,239 --> 00:46:30,200 Speaker 1: or wherever you listen to your favorite shows. Ye