WEBVTT - What are cosmic strings? 0:00:08.480 --> 0:00:11.200 Hey, Daniel, I have a question for you about how 0:00:11.360 --> 0:00:15.640 physics works. All right, shoot, yeah, what happens when it 0:00:15.720 --> 0:00:19.720 doesn't work? Like what happens when you're wrong? That really 0:00:19.760 --> 0:00:24.400 depends depends on what how wrong you are. No, it 0:00:24.440 --> 0:00:28.960 depends on whether you're an experimentalist or a theorist. It 0:00:29.000 --> 0:00:32.000 makes a difference. Oh yeah. For an experimentalist, if you 0:00:32.000 --> 0:00:35.760 are wrong one time, it's like a career death. It's 0:00:35.800 --> 0:00:38.680 like getting caught from murder. You know, once is enough 0:00:38.760 --> 0:00:42.159 to send you away forever. You murdered science. If you 0:00:42.640 --> 0:00:47.080 if your results are wrong, you murdered your credibility. But 0:00:47.200 --> 0:00:49.000 not for a theorist. Like if a theorist is wrong, 0:00:49.159 --> 0:00:53.400 there's no consequence. No, almost every single paper written by 0:00:53.440 --> 0:00:56.840 a theorist is wrong, and in fact, if they are 0:00:56.920 --> 0:01:00.520 right even one time, they win. The Nobel problem does 0:01:00.600 --> 0:01:03.400 sound like better? Odds, Daniel, Why did you even become 0:01:03.440 --> 0:01:22.960 an experimentalist? I asked myself that question every day. I 0:01:23.080 --> 0:01:26.840 am Jorge make cartoonists and the creator of PhD comics. Hi, 0:01:27.040 --> 0:01:30.120 I'm Daniel. I'm a particle of physicist, and though I've 0:01:30.160 --> 0:01:32.679 never been wrong in a scientific paper, I have zero 0:01:32.760 --> 0:01:35.720 Nobel prizes, No wait, that's not actually true. I do 0:01:35.800 --> 0:01:37.959 have a tiny slice of a Nobel Prize. Well, you 0:01:38.000 --> 0:01:40.680 could be wrong about having a Nobel Prize, like you could. 0:01:41.520 --> 0:01:44.080 I could write a paper about having a Nobel Prize 0:01:44.560 --> 0:01:47.080 and they'll be wrong and then get a Nobel Prize 0:01:47.080 --> 0:01:51.360 for it in literature maybe. But anyways, welcome to our 0:01:51.360 --> 0:01:55.240 podcast Daniel and Jorge Explain the Universe Even the Wrong Parts, 0:01:55.600 --> 0:01:58.240 a production of I Heart Radio, in which we take 0:01:58.280 --> 0:02:00.840 a trip around the universe, giving you a tour of 0:02:01.000 --> 0:02:04.640 everything that's amazing, everything that's exciting, everything that's real, and 0:02:04.760 --> 0:02:08.240 everything that's theoretical. Not just what's out there in the universe, 0:02:08.280 --> 0:02:11.680 but what's inside the minds of scientists, what they're hoping 0:02:11.720 --> 0:02:15.040 to discover out there in our universe. That's right, We 0:02:15.120 --> 0:02:17.840 take you on a trip across the cosmos, not just 0:02:18.000 --> 0:02:21.200 to see what's there, but what might be there. What's 0:02:21.280 --> 0:02:25.360 physicists think might be the next big idea that could 0:02:25.400 --> 0:02:29.080 revolutionize how we understand the universe. And we have a 0:02:29.120 --> 0:02:31.800 special group of people whose job it is just to 0:02:31.919 --> 0:02:35.480 come up with crazy ideas that might describe our universe. 0:02:35.639 --> 0:02:37.239 You have a group of people just to be wrong. 0:02:37.400 --> 0:02:39.800 Is that kind of how it works. They only have 0:02:39.880 --> 0:02:43.000 to be right occasionally. But yeah, basically, just throw ideas 0:02:43.000 --> 0:02:48.079 out there. It's like the brain, the brain trust. Yeah, 0:02:48.120 --> 0:02:50.320 it's like a brainstorming, you know, like maybe the universe 0:02:50.360 --> 0:02:52.600 works this way. Go check. Oh no, I guess not. 0:02:52.760 --> 0:02:55.200 Maybe the universe works that way. Go check. Oh no, 0:02:55.280 --> 0:02:57.839 I guess not. Keep coming up with ideas, folks, Yeah, 0:02:57.840 --> 0:03:01.520 because the universe is pretty crazy out there. You know, 0:03:01.720 --> 0:03:03.880 there are a lot of things that we didn't expect, 0:03:04.560 --> 0:03:08.839 and so as crazy as an idea might seem right now, 0:03:09.040 --> 0:03:13.560 it could be right. Yep. Absurdity is no obstacle to reality. 0:03:13.960 --> 0:03:15.680 I mean, you can't take a theory of physics and 0:03:15.720 --> 0:03:19.800 say that's too crazy, because some of these crazy ideas 0:03:19.840 --> 0:03:23.440 turned out to be real, you know, quantum mechanics and relativity. 0:03:23.760 --> 0:03:26.680 There have been moments in history when we had to 0:03:26.720 --> 0:03:30.040 accept things that were very difficult to swallow, and that 0:03:30.080 --> 0:03:32.320 means we need to keep our minds wide open to 0:03:32.400 --> 0:03:35.720 future crazy ideas. Yeah, you could be absurd and be 0:03:35.840 --> 0:03:40.040 right at the same time. That's the situation of the universe. 0:03:40.200 --> 0:03:43.040 That's your review of the Universe on its Amazon web page. 0:03:43.760 --> 0:03:49.400 Absurd but right, absurved but true. Five stars. Yeah, that's 0:03:49.440 --> 0:03:53.920 kind of like this podcast a Cartoonists and physicism physics 0:03:53.920 --> 0:03:56.360 for an hour, And I wonder what that's like sometimes 0:03:56.360 --> 0:03:58.040 for a theorist, because I'm not a theorist. You know, 0:03:58.080 --> 0:04:00.600 you spend your life coming up with ideas maybe there's 0:04:00.640 --> 0:04:03.440 this particle, maybe the universe works that way, and and 0:04:03.560 --> 0:04:08.120 predicting them and suggesting ways to check but almost never correct. Right. 0:04:08.320 --> 0:04:11.360 Most theorists who write papers, most of their theories don't 0:04:11.360 --> 0:04:13.680 even get checked because we can't check all of them, 0:04:13.880 --> 0:04:16.640 and when they do, mostly they just get ruled out. Yeah. 0:04:16.680 --> 0:04:18.480 I guess there are a lot of theorists out there 0:04:19.120 --> 0:04:22.560 and they can't all be right right, and they can't 0:04:22.600 --> 0:04:26.640 all be checked. So how does how do these ideas 0:04:26.760 --> 0:04:29.760 come through to get checked? Yeah? Well, if you're a theorist, 0:04:29.760 --> 0:04:31.520 you have some crazy new idea, you say, I think 0:04:31.520 --> 0:04:33.920 the universe works this way, and then you have to 0:04:33.960 --> 0:04:35.880 make a prediction. You have to say, well, if somebody 0:04:35.880 --> 0:04:39.200 did such and such experiment, they could verify my theory. 0:04:39.360 --> 0:04:42.839 Like Einstein had his theory relativity, and he predicted something 0:04:42.839 --> 0:04:45.680 would happen when light bent around the sun or when 0:04:45.760 --> 0:04:48.160 light bent around the moon during an eclipse, so it 0:04:48.240 --> 0:04:51.400 make a very specific prediction. Then the key is you 0:04:51.400 --> 0:04:54.839 have to find an experimentalist someone to do that experiment 0:04:55.040 --> 0:04:58.200 and check your prediction. If you can't convince anybody that 0:04:58.279 --> 0:05:01.040 your prediction is worth checking, it just doesn't get checked. 0:05:01.279 --> 0:05:05.080 Is there like an app for physicists to match experimentalists 0:05:05.120 --> 0:05:09.839 with theories, you know, like a dating app physics or 0:05:10.080 --> 0:05:14.400 or checker. Yeah, I'm not sure. Um, you know it's 0:05:14.440 --> 0:05:18.000 sort of arbitrary. You know, experimentals will read a paper 0:05:18.040 --> 0:05:19.880 and say, oh, that's really cool, I want to check that. 0:05:20.000 --> 0:05:22.680 Or me as an experimentals, I'll go to conferences and 0:05:22.720 --> 0:05:25.360 talk to theorists and hear about the new ideas and 0:05:25.640 --> 0:05:28.359 try to think about what's most interesting to test. Because 0:05:28.360 --> 0:05:30.599 you can't test everything, you have to make your choices. Yeah, 0:05:30.600 --> 0:05:33.839 I guess you swipe left or right depending on whether 0:05:33.880 --> 0:05:35.599 you think it could be right or what are you 0:05:35.600 --> 0:05:38.840 based on? Like is it is it? Are you tempted 0:05:38.880 --> 0:05:40.920 by like, oh that would be a big fish to catch, 0:05:41.120 --> 0:05:44.880 or are you tempted by like is this an easy 0:05:44.960 --> 0:05:47.520 fish that I could verify? Well, that's a great question. 0:05:47.760 --> 0:05:51.480 I'm a bit unusual in particle physics. Most people choose 0:05:51.560 --> 0:05:55.400 theories that they think sound sort of aesthetically beautiful, like 0:05:55.520 --> 0:05:58.560 supersymmetry and gravity and all these things. They have like 0:05:58.600 --> 0:06:02.120 a deep fear redical reason to motivate that theory, like 0:06:02.320 --> 0:06:05.200 why we think it exists? Um. For me, I'm more 0:06:05.240 --> 0:06:08.160 interested in stuff that's uh going to be a surprise, 0:06:08.279 --> 0:06:11.039 Like I'd like to look for something that isn't predicted, 0:06:11.480 --> 0:06:14.880 So I try to do experiments that nobody's predicted, because 0:06:14.880 --> 0:06:17.479 then if you see something new, a new particle, then 0:06:17.560 --> 0:06:19.320 you get to be the first person to describe it, 0:06:19.320 --> 0:06:21.720 and it sort of comes out as a pleasant surprise 0:06:21.800 --> 0:06:24.600 for the community. So it is like a dating app. 0:06:24.800 --> 0:06:26.599 You swipe left or right if it's like, oh this 0:06:26.640 --> 0:06:30.320 is beautiful, I like it, or on this floats my boat, 0:06:30.560 --> 0:06:33.160 I'm gonna swipe it. All right, You're right, I give up. 0:06:33.200 --> 0:06:35.240 Physics is just like a dating app. It's basically the 0:06:35.279 --> 0:06:39.599 same thing. Well a lot of it. Amazing and incredible 0:06:39.640 --> 0:06:42.000 discoveries have been made this way. For example, the Higgs 0:06:42.040 --> 0:06:45.120 boson was really just a theory out of the blue, 0:06:45.320 --> 0:06:46.919 and it was a theory for a long time until 0:06:46.920 --> 0:06:49.320 people decided to try to test it. That's right, and 0:06:49.360 --> 0:06:52.400 people spend decades trying to test this theory, and finally 0:06:52.400 --> 0:06:54.440 we build a collider or powerful enough that we could 0:06:54.560 --> 0:06:58.000 create the Higgs boson and prove that it existed. And 0:06:58.040 --> 0:07:00.480 so this theory is to fifty years or Elier had 0:07:00.480 --> 0:07:03.200 predicted the existence of this particle, was proved right and 0:07:03.440 --> 0:07:06.320 got his Nobel prize. Yeah, that was like a like 0:07:06.360 --> 0:07:08.760 a twenty billion dollars swipe there, you know, that was 0:07:08.800 --> 0:07:13.720 a big swipe that that was good dollars. Yeah, but 0:07:13.800 --> 0:07:16.080 you know, he wasn't the only one to predict it. 0:07:16.080 --> 0:07:18.239 And there was a lot of controversy when we discovered 0:07:18.280 --> 0:07:20.680 the Higgs boson. Who was going to get the prize 0:07:20.720 --> 0:07:23.200 for it? Should it just be Higgs, should also be 0:07:23.360 --> 0:07:25.720 this guy Englert who was around and wrote a lot 0:07:25.760 --> 0:07:27.960 of very similar papers but didn't get his name on 0:07:28.000 --> 0:07:30.440 the particle. And then there was a whole other group 0:07:30.440 --> 0:07:33.600 of people that wrote very similar papers, but we didn't 0:07:33.640 --> 0:07:35.800 get any part of the prize. That's right, And so 0:07:35.920 --> 0:07:39.360 today we'll be talking about a prediction from a theorist 0:07:39.520 --> 0:07:42.760 that maybe should have gotten the Higgs Nobel Prize but didn't. 0:07:43.360 --> 0:07:46.360 And he made his second prediction about the universe that 0:07:46.400 --> 0:07:48.560 we're going to be talking about today. That's right. And 0:07:48.600 --> 0:07:51.360 this comes from a question from a listener. Somebody wrote 0:07:51.400 --> 0:07:53.760 it and said, hey, could you explain this to us? 0:07:53.880 --> 0:07:55.720 I just don't get it. Yeah, So this is a 0:07:55.800 --> 0:07:59.200 question that Peter from Poland sent us via email, and 0:07:59.240 --> 0:08:00.760 so to be on the pro and we'll be asking 0:08:00.800 --> 0:08:10.000 the question what is a cosmic string? I don't want 0:08:10.000 --> 0:08:12.240 to string people along. Let's just let's just get down 0:08:12.240 --> 0:08:15.440 to it. Daniel. Yeah, well I was thinking, you know, 0:08:15.600 --> 0:08:19.280 silly string versus string theory, and there's a lot of 0:08:19.280 --> 0:08:24.160 different combinations there, but a lot of strings in physics. Yeah, 0:08:24.200 --> 0:08:26.480 it's a great question. Thank you Peter from Poland for 0:08:26.600 --> 0:08:29.760 writing in, and anybody out there, if there's something in 0:08:29.800 --> 0:08:32.480 physics you've heard about but haven't really understood any of 0:08:32.520 --> 0:08:34.920 the explanations, send to us. We're going to try to 0:08:34.960 --> 0:08:37.720 break it down. And this is a tantalizing subject because 0:08:37.880 --> 0:08:41.280 we're not just talking about strings. We're talking about cosmic strings. 0:08:41.480 --> 0:08:44.480 So they sound like a very big deal, and they 0:08:44.480 --> 0:08:46.760 are kind of a big deal. They're not small strings 0:08:46.800 --> 0:08:49.480 like maybe some people might be imagining it. That's right. 0:08:49.640 --> 0:08:53.079 This is not you know, star studied strings in your 0:08:53.160 --> 0:08:55.800 drawer or anything like that. These are things that could 0:08:55.800 --> 0:08:59.360 span the entire observable universe. And so we were wondering 0:08:59.679 --> 0:09:02.559 how people had heard of these two words put together 0:09:02.640 --> 0:09:07.760 costmaking strings out there, and how many people maybe even 0:09:07.800 --> 0:09:10.680 had an idea but what it could be. So, as usual, 0:09:10.760 --> 0:09:13.199 Daniel went out there and as people in the street, 0:09:13.480 --> 0:09:16.679 if they've heard what a cosmic string is, so before 0:09:16.679 --> 0:09:18.600 you hear these answers, think to yourself for a moment, 0:09:18.640 --> 0:09:20.720 do you know what a cosmic string is? What would 0:09:20.800 --> 0:09:23.320 you say if I asked you on the street. Here's 0:09:23.320 --> 0:09:26.400 what people had to say. It sounds like a Marvel 0:09:26.480 --> 0:09:30.240 movie before me? Is that similar to string theory? The 0:09:30.320 --> 0:09:34.640 loops that way upon it's like a fifth dimension potentially? 0:09:34.679 --> 0:09:36.280 Do you know all this stuff? I don't know any 0:09:36.280 --> 0:09:42.200 of this. I don't know any it's something, um, I 0:09:42.200 --> 0:09:48.800 don't have no idea. Cosmic strings something that uh, and 0:09:48.840 --> 0:09:54.120 then I think that's what space string. QUITE have no idea. 0:09:54.160 --> 0:09:56.520 If you laugh, is it sound funny? It just sounds 0:09:56.559 --> 0:09:59.320 like like science fiction. I heard of cosmic bowling. You're 0:09:59.320 --> 0:10:02.680 not cosmic cosmic bowling? What's that? That's when they shut 0:10:02.679 --> 0:10:07.320 down the lights for Friday night bowling, strings that you know, 0:10:07.520 --> 0:10:13.960 unite like different potential space and time like you Yeah, 0:10:14.000 --> 0:10:16.840 like space and time like a pass I guess in 0:10:16.880 --> 0:10:21.440 a way when it's stringing together, str together, I have 0:10:21.520 --> 0:10:27.760 no idea something to deal with. I don't know um energy, energy, 0:10:27.880 --> 0:10:30.000 and I don't have no idea how okay, but so 0:10:30.080 --> 0:10:36.160 very much obviously cosmic, yes, but strings those starts together now, 0:10:36.640 --> 0:10:39.000 all right, Not a lot of familiarity, although I do 0:10:39.120 --> 0:10:41.480 like the answer the person who said it sounds like 0:10:41.480 --> 0:10:46.400 a Marvel movie to me, which it totally does. You know, 0:10:46.920 --> 0:10:52.400 infinity stones, cosmic strings, quantum realm. You're you guys are 0:10:52.400 --> 0:10:54.679 all watching the same movies. You could put cosmic in 0:10:54.720 --> 0:10:56.520 front of anything. It would sounds like a Marvel movie. 0:10:56.640 --> 0:11:00.240 Cosmic quantum, cosmic bowling. I like that answer. I was like, yeah, 0:11:00.280 --> 0:11:02.080 that does sound like a good idea. I'd like to 0:11:02.080 --> 0:11:10.360 go to cosmic bowling, cosmic breakfast, cosmic fast. All right. So, 0:11:10.440 --> 0:11:12.000 not a lot of people seem to know what it was, 0:11:12.040 --> 0:11:15.280 although it definitely sounded science and science fiction. A lot 0:11:15.320 --> 0:11:16.920 of people said, oh, it sounds like science fiction, or 0:11:16.960 --> 0:11:20.959 it sounds like something that might be related to string 0:11:21.000 --> 0:11:24.760 theory or physics or energy. It definitely has a science 0:11:24.800 --> 0:11:27.000 feel to it. Yeah, and it might have just been 0:11:27.040 --> 0:11:28.840 the way my hair looked that day. Maybe it looked 0:11:28.880 --> 0:11:31.400 more like a crazy physicist, or maybe it just does 0:11:31.440 --> 0:11:33.840 sound like a sort of a physics thing. So people 0:11:33.840 --> 0:11:36.280 are definitely guessing that. I'm trying to imagine how you 0:11:36.320 --> 0:11:39.040 can look more like a physicist, Daniel, It's kind of hard. 0:11:39.360 --> 0:11:40.959 It's kind of hard to imagine. I don't know. I 0:11:41.000 --> 0:11:42.480 guess I could put on a lab coat. I mean 0:11:42.520 --> 0:11:44.680 I don't usually with a lab code when I'm walking around. 0:11:45.600 --> 0:11:48.800 You put on a marble costume and boom, I need 0:11:48.840 --> 0:11:50.920 an m c U lab coade so I can do 0:11:50.960 --> 0:11:53.400 both things at once. Oh, that would be that's a 0:11:53.400 --> 0:11:57.000 good idea. Actually print um something fun on a lap code. 0:11:57.320 --> 0:12:00.360 M that sounds like merch. Get on that people, next 0:12:00.360 --> 0:12:03.000 product for the Daniel and Jorge explain the universe store. 0:12:04.360 --> 0:12:07.080 But all right, so let's get into it. Daniel, what 0:12:07.080 --> 0:12:10.199 what are they? What is a cosmic string? And I 0:12:10.440 --> 0:12:12.839 I am totally with the people on the street. I've 0:12:12.880 --> 0:12:15.360 never heard of this concept before this morning. Well there's 0:12:15.360 --> 0:12:19.040 a good reason, because cosmic strings are a pretty crazy idea. 0:12:19.360 --> 0:12:23.000 They're pretty far out there, but they're really fun and 0:12:23.040 --> 0:12:25.880 conceptually sort of mind blowing, which is why I think 0:12:25.920 --> 0:12:28.720 the theory stuck around for a while. People get swiping 0:12:28.760 --> 0:12:32.120 it because it sounded fun. Yeah, everybody wants this theory 0:12:32.120 --> 0:12:34.880 to be true. And so what is a cosmic string? 0:12:34.920 --> 0:12:38.880 A cosmic string is a line in space where the 0:12:38.920 --> 0:12:41.719 space itself is a little bit different from the way 0:12:41.800 --> 0:12:44.240 spaces for us, from me and you and most of 0:12:44.240 --> 0:12:46.400 the space in the universe. It's like a little bit 0:12:46.440 --> 0:12:49.120 of leftover from the Big Bang where it never quite 0:12:49.160 --> 0:12:52.320 cooled and relaxed the way the space for us has. 0:12:52.600 --> 0:12:54.840 It's like a pocket, like a pocket or a bubble, 0:12:54.960 --> 0:12:57.000 or like a stretch dog bubble. Is that kind of 0:12:57.000 --> 0:13:00.200 what mean? No, it's a really long, thin line, like 0:13:00.240 --> 0:13:03.920 it's maybe a phemptometer wide, so like super duper tiny, 0:13:04.000 --> 0:13:06.719 like the width of a proton. But then it can 0:13:06.720 --> 0:13:09.000 be super long, like it could be as long as 0:13:09.040 --> 0:13:13.079 the observable universe, like nine billion light years. It's kind 0:13:13.120 --> 0:13:17.200 of like a crack in space itself. Yeah, and you 0:13:17.280 --> 0:13:20.240 have to think about what space is and remember that 0:13:20.320 --> 0:13:23.280 space used to be really different. Right back when the 0:13:23.400 --> 0:13:27.000 universe was created. Everything was hot and dense and there's 0:13:27.040 --> 0:13:30.040 a lot of energy everywhere. And remember that space is 0:13:30.080 --> 0:13:32.959 not emptiness. Space has all this stuff in It has 0:13:32.960 --> 0:13:36.240 these quantum fields. And when you put energy into space, 0:13:36.280 --> 0:13:39.240 what you're doing is you're making those fields wiggle. And 0:13:39.320 --> 0:13:42.280 so back in the very early universe, those fields were 0:13:42.320 --> 0:13:45.280 going crazy because it was so much energy everywhere. So 0:13:45.360 --> 0:13:47.839 everything was wiggling really fast, and everything had a lot 0:13:47.880 --> 0:13:50.400 of energy. In our book, we talked about how space 0:13:50.520 --> 0:13:53.400 is kind of like a goo. It's like, it's not emptiness. 0:13:53.920 --> 0:13:57.520 It's more like it's like something that you're swimming in almost, 0:13:57.640 --> 0:14:00.760 and it can wiggle and bed and push you in 0:14:01.000 --> 0:14:04.120 different directions. Right, that's right. Gravity does really weird things 0:14:04.160 --> 0:14:06.200 to space. It can stretch it, it can bend it, it 0:14:06.120 --> 0:14:08.120 it can ripple it. But for now, let's just think 0:14:08.160 --> 0:14:11.040 about like one unit of space, Like what's in that 0:14:11.120 --> 0:14:13.560 box of space? And in that box of space are 0:14:13.640 --> 0:14:16.600 quantum fields. Now, the universe started out really hot and 0:14:16.679 --> 0:14:20.120 dense and really energetic, and those fields had a lot 0:14:20.160 --> 0:14:22.760 of energy in them. But the space that we're familiar 0:14:22.800 --> 0:14:24.840 with that operates in the way that we expect, like 0:14:25.200 --> 0:14:28.520 has electrons in it and and atoms and stuff that 0:14:28.600 --> 0:14:31.160 only came about after the universe relaxed a little bit. 0:14:31.320 --> 0:14:35.280 We talked about on the Higgs Boson episode that there's 0:14:35.360 --> 0:14:37.960 one of these quantum fields, the Higgs one, that when 0:14:37.960 --> 0:14:41.160 it relaxed, when the universe cooled down, that this field 0:14:41.240 --> 0:14:43.240 didn't go all the way down to zero, sort of 0:14:43.240 --> 0:14:47.240 got stuck on a shelf. Right, Like the field that 0:14:47.320 --> 0:14:51.360 the universe is made out of are not necessarily static, 0:14:51.680 --> 0:14:54.160 like they can be kind of buzzing with energy. That's right. 0:14:54.200 --> 0:14:56.560 Every time you have a particle that's a ripple in 0:14:56.600 --> 0:14:59.320 the field, which means you've injected energy into it. Now, 0:14:59.400 --> 0:15:01.280 most of the few can go down to zero like 0:15:01.280 --> 0:15:03.960 you've got no electrons in your box of space. That 0:15:04.000 --> 0:15:07.200 fuel is at zero. But the Higgs boson never gets 0:15:07.200 --> 0:15:09.480 down to zero. Got stuck on this shelf. And so 0:15:09.520 --> 0:15:13.280 how does that explain these pockets or these cracks in space? 0:15:13.480 --> 0:15:16.120 So what happens when the universe is expanding, is it 0:15:16.120 --> 0:15:18.760 it's cooling, right, All this energy is getting spread out 0:15:18.960 --> 0:15:21.680 into more and more space. It's like you're stretching out 0:15:21.720 --> 0:15:24.600 the fields, right, Like you're stretching them out basically, and 0:15:24.640 --> 0:15:27.480 so they calmed down. Yeah, you have the same amount 0:15:27.520 --> 0:15:30.040 of energy in more space, and so it gets deluded. 0:15:30.080 --> 0:15:33.240 So everything's like cooling and relaxing and sort of like 0:15:33.680 --> 0:15:36.600 you know, you you toss your blanket over your bed 0:15:36.640 --> 0:15:39.760 and it sort of settles down and settles over your bed, right, 0:15:40.480 --> 0:15:45.320 like a cosmic nap is like a cosmic blanket. Yeah, 0:15:45.400 --> 0:15:48.320 and it settles down. But the Higgs field got stuck. Right. 0:15:48.600 --> 0:15:51.000 But here's the thing. The Higgs field has lots of 0:15:51.040 --> 0:15:54.240 different ways to get stuck on that shelf. Is that 0:15:54.280 --> 0:15:57.480 shelf is not just like one little balcony. It's like 0:15:57.520 --> 0:16:01.240 a long round balcony, and the universe can get stuck 0:16:01.240 --> 0:16:03.800 in different spots on that shelf. And so as the 0:16:03.880 --> 0:16:06.840 universe is cooling, if this chunk of space over here 0:16:07.280 --> 0:16:10.040 got stuck on a different spot then that chunk of space, 0:16:10.440 --> 0:16:13.560 then there's this sort of boundary between them, this place 0:16:13.680 --> 0:16:16.320 between them that doesn't quite work because it's sort of 0:16:16.360 --> 0:16:19.720 trapped between space that got that cooled in two different ways. 0:16:20.600 --> 0:16:23.280 It's kind of like how you know, water or air 0:16:23.400 --> 0:16:27.880 has different states like solid liquid and gas, and you know, 0:16:28.800 --> 0:16:32.040 as you cool something down, you can form these little 0:16:32.040 --> 0:16:36.040 pockets of liquid or gas or what's either one solid 0:16:37.360 --> 0:16:40.200 water crystal. Yeah, it's like when you, like when you 0:16:40.240 --> 0:16:43.240 stick water into the freezer and it cools down and 0:16:43.640 --> 0:16:47.280 forms ice. It doesn't form like this perfect solid of ice. 0:16:47.360 --> 0:16:50.560 It forms like it has bowls and cracks and wiggles 0:16:50.560 --> 0:16:51.760 and it is that kind of what you're saying, is 0:16:51.840 --> 0:16:54.400 happened happened? Or how is happening to space right now? 0:16:55.040 --> 0:16:57.760 Exactly like that, if you cool water down, then you 0:16:57.800 --> 0:16:59.960 get a crystal. But it doesn't, as you say, turn 0:17:00.040 --> 0:17:02.520 into a crystal all at once. There's these sites that 0:17:02.560 --> 0:17:05.520 begin because they're the coldest, little dots, and the crystals 0:17:05.520 --> 0:17:08.600 start to form there, and then they form out from 0:17:08.600 --> 0:17:11.280 those little spots where they have nucleated. And then what 0:17:11.359 --> 0:17:15.280 happens when two crystals meet, You have this boundary, right, 0:17:15.600 --> 0:17:17.280 and you don't have a perfect crystal. You have a 0:17:17.320 --> 0:17:19.840 defect in the crystal. That's why, like some diamonds are 0:17:19.880 --> 0:17:22.440 perfect and some diamonds are not because there's a defect 0:17:22.440 --> 0:17:24.720 there where in the crystal where one half of it 0:17:24.800 --> 0:17:27.080 is cooled in a different time than the other half, 0:17:27.240 --> 0:17:30.080 so they're not all lined up perfectly. The same thing 0:17:30.200 --> 0:17:33.919 happened to space, maybe, like there are imperfections in space, 0:17:34.320 --> 0:17:37.520 there are imperfections in their defects or cracks in space. 0:17:37.840 --> 0:17:40.080 Where on one side the Higgs field, it's at the 0:17:40.160 --> 0:17:43.159 same level, right, it's just pointed in a different direction, 0:17:43.160 --> 0:17:45.240 because the Higgs field has sort of two we call 0:17:45.280 --> 0:17:48.159 them degrees of freedom, the level let it relaxed that 0:17:48.440 --> 0:17:51.600 and also where on that shelf it got stuck. So 0:17:51.640 --> 0:17:53.439 if this chunk of space is stuck on a different 0:17:53.440 --> 0:17:55.720 spot in the shelf, then that chunk of space, it's 0:17:55.760 --> 0:17:59.199 sort of like your ice cooling at different ways. In 0:17:59.200 --> 0:18:02.159 different ways, the stoles are oriented in different directions, and 0:18:02.200 --> 0:18:04.400 so at the boundary you get this thing that doesn't 0:18:04.480 --> 0:18:06.840 quite make sense. So I always thought the universe was 0:18:07.040 --> 0:18:09.560 pretty pretty good, but I guess it's not a triple 0:18:09.600 --> 0:18:13.960 A diamond quality space. I mean, I love our universe. 0:18:14.000 --> 0:18:16.159 I would not trade it in for anything. I think 0:18:16.200 --> 0:18:18.120 it's perfect just the way it is. But it might 0:18:18.200 --> 0:18:20.119 have these cracks in it, right, And we don't know. 0:18:20.240 --> 0:18:22.560 We have never seen one of these things, but it 0:18:22.680 --> 0:18:25.080 might have these cracks in it. That's the idea. That's 0:18:25.240 --> 0:18:29.520 the concept of a cosmic string, cosmic flaws in space itself. 0:18:29.520 --> 0:18:32.720 And so along that line, it's like the universe never 0:18:32.800 --> 0:18:34.879 got to cool because it doesn't know like should I 0:18:34.880 --> 0:18:36.439 cool in this way or should I cool in the 0:18:36.520 --> 0:18:38.840 other way. It's sort of like trapped between them, and 0:18:38.880 --> 0:18:42.160 so it still has that energy density from the initial 0:18:42.280 --> 0:18:45.239 universe when everything was really hot and dense. And so 0:18:45.320 --> 0:18:48.200 these cosmic strings, even though they're really really thin, they're 0:18:48.240 --> 0:18:52.240 like a femtometer wide. They're incredibly massive, and they could 0:18:52.240 --> 0:18:54.760 be holding energy like the cracks or the flaws in 0:18:54.800 --> 0:18:58.520 the universe could be storing some sort of energy or 0:18:58.680 --> 0:19:03.560 tension into them. Absolutely incredible amounts of energy. Like two 0:19:03.600 --> 0:19:07.200 centimeters of a cosmic string weighs as much as Mount Everest. 0:19:07.760 --> 0:19:11.520 A kilometer of cosmic string weighs more than the Earth. 0:19:12.080 --> 0:19:13.800 And so we're talking about these things. They could be 0:19:13.840 --> 0:19:17.879 like ninety billion light years long. It's an enormous amount 0:19:17.920 --> 0:19:21.479 of energy. What you just totally correct my mind here, Daniel, 0:19:21.920 --> 0:19:26.160 cosmically cosmically dude. But all right, so let's get into 0:19:26.200 --> 0:19:30.120 it and why is physicists think these crazy cracks might 0:19:30.200 --> 0:19:32.960 exist and whether or not they're real. But first let's 0:19:32.960 --> 0:19:47.680 take a quick break. Okay, so you're saying that as 0:19:47.800 --> 0:19:51.560 the universe was cooling or assets cooling right now, you 0:19:51.680 --> 0:19:56.520 might have these areas these lines, these huge lines in 0:19:56.600 --> 0:19:59.919 space that are sort of like cracks, like where space 0:20:00.200 --> 0:20:05.040 is kind of freezing into different crystals like structures or 0:20:05.160 --> 0:20:08.240 different modes, and so you have these kind of edges 0:20:08.320 --> 0:20:11.679 to the wrinkles in space itself due to the Higgs 0:20:11.680 --> 0:20:14.439 field precisely, and we are in the crystal part, right, 0:20:14.480 --> 0:20:16.720 we're in the part of space that cooled, and these 0:20:16.840 --> 0:20:19.920 chunks of space that all cool sort of together. That's 0:20:19.960 --> 0:20:23.080 like could be as wise nine billion night years like 0:20:23.119 --> 0:20:25.480 the observable universe. So it's not like you have a 0:20:25.480 --> 0:20:27.560 little pocket of space, assize your hand and the next 0:20:27.560 --> 0:20:30.040 pocket is different, the next pocket is different. If there 0:20:30.080 --> 0:20:33.919 are these pockets and they're vast, they're incredibly enormous, but 0:20:33.960 --> 0:20:36.480 then at their edges there can be these cracks. And 0:20:36.520 --> 0:20:40.800 you're saying, these edges, these boundaries look like strings, and 0:20:41.000 --> 0:20:43.560 so why don't they look like walls or like you know, 0:20:43.720 --> 0:20:46.800 planes out in space. Why is it shape like a 0:20:46.840 --> 0:20:50.240 long like you're super thin but really long string. Yeah, 0:20:50.280 --> 0:20:53.520 that's a great question. That's because the Higgs boson. The 0:20:53.600 --> 0:20:56.240 field for the Higgs has a lot of different ways 0:20:56.280 --> 0:20:59.199 you can relax, Like there's one level at which you 0:20:59.200 --> 0:21:01.639 can relax one and energy level, but on that energy 0:21:01.720 --> 0:21:04.439 level can sort of point in a lot of different directions. 0:21:04.960 --> 0:21:06.879 And so the way to get a boundary is like 0:21:06.920 --> 0:21:09.720 if you had two different energy levels and and the 0:21:09.760 --> 0:21:12.800 boundary like a would be like a plane between them. 0:21:12.880 --> 0:21:16.199 But um, because there's only one energy level, everywhere in 0:21:16.240 --> 0:21:18.760 space has that energy level, but they just point in 0:21:18.760 --> 0:21:21.479 different directions. And so what you get is this defect 0:21:21.520 --> 0:21:24.119 that's like a string. And then as you go around 0:21:24.359 --> 0:21:27.720 the string, the Higgs field is pointing in different directions, 0:21:27.760 --> 0:21:30.600 and so it points in a different direction every point 0:21:30.640 --> 0:21:33.040 around the string. And then the only place where you 0:21:33.080 --> 0:21:36.200 can't get sort of like smoothness is along this one 0:21:36.320 --> 0:21:40.160