WEBVTT - What is Supersymmetry? 0:00:07.600 --> 0:00:09.720 Hey, Daniel, how do you convince the government to give 0:00:09.760 --> 0:00:13.640 you ten billion dollars? Oh, you just have to promise 0:00:13.840 --> 0:00:17.239 an aircraft carrier or two. I think that's right. That's 0:00:17.239 --> 0:00:18.840 about the cost of one. But it's also kind of 0:00:18.840 --> 0:00:22.400 the cost of a big physics experiment, right, that's true. 0:00:22.440 --> 0:00:25.040 Although I didn't personally get the check for ten billion 0:00:25.079 --> 0:00:27.360 dollars for the large H. John collider. But you're write 0:00:27.360 --> 0:00:30.040 a bunch of world governments all chipped in and spent 0:00:30.200 --> 0:00:33.400 a lot of money on a physics experiment, right, And 0:00:33.400 --> 0:00:36.080 and I imagined that in each of those countries there 0:00:36.080 --> 0:00:37.839 had to be some physicists who went up to the 0:00:37.840 --> 0:00:40.760 government officials and said, hey, gave was this money to 0:00:40.800 --> 0:00:43.360 discover this thing or that thing? Right? Um? Yeah, Well, 0:00:43.400 --> 0:00:46.120 they don't send me to pitch these things to the government, 0:00:46.200 --> 0:00:49.320 probably very good reason. I'm unusual in particle physics. I 0:00:49.320 --> 0:00:52.919 think most particle physicists like to make more concrete predictions 0:00:52.960 --> 0:00:55.200 about what we might find. My view is that we 0:00:55.240 --> 0:00:59.960 should just sell the exploration. But I think the one 0:01:00.000 --> 0:01:03.040 you're referring to is a kind of a famous area 0:01:03.200 --> 0:01:08.640 in particle physics about the storage for the search for supersymmetry. 0:01:08.720 --> 0:01:10.160 Exactly a lot of people thought we were going to 0:01:10.240 --> 0:01:14.839 find supersymmetry at the large a John Collider. So far nothing. 0:01:15.760 --> 0:01:17.839 I think I saw that movie from the eighties, wasn't 0:01:17.840 --> 0:01:22.440 it called Despritley Seeking Susie. That's right, supersymmetry is short 0:01:22.480 --> 0:01:27.320 and sometimes as Susie Susie here, give me a billion dollars, 0:01:27.560 --> 0:01:30.080 I'll find her. Okay, Um, you start looking and I'll 0:01:30.080 --> 0:01:50.680 send you a chet. Sounds good. I'll be right back. Hi. 0:01:50.720 --> 0:01:53.760 I'm Organ and I'm Daniel, and welcome to our podcast, 0:01:53.880 --> 0:01:56.920 Daniel and Jorge Explain the Universe, a production of I 0:01:57.120 --> 0:01:59.480 Heart Radio, in which we take things in the universe 0:01:59.480 --> 0:02:01.800 and explain them to you. Things that are super, things 0:02:01.840 --> 0:02:04.760 that are not so super, things that are symmetrical, and 0:02:04.880 --> 0:02:09.079 things that are asymmetrical, things that are antithetical to everything 0:02:09.120 --> 0:02:12.359 you believe in, but actually true. That's right. Today on 0:02:12.400 --> 0:02:16.440 the podcast, we're going to talk about a pretty kind 0:02:16.480 --> 0:02:18.799 of it's kind of a corner of particle physics, right 0:02:19.000 --> 0:02:21.120 and it's it's probably not super well known, but it 0:02:21.240 --> 0:02:26.040 is it can have incredible implications for our entire theory 0:02:26.120 --> 0:02:28.960 about the universe. Right. Yeah, it's sort of like particle 0:02:29.040 --> 0:02:32.880 physicists big hope. Right, it's like a beautiful idea that 0:02:32.919 --> 0:02:35.640 everybody really really wishes were true. It's solve a bunch 0:02:35.639 --> 0:02:38.520 of problems. It would work really well, it would be gorgeous. 0:02:39.160 --> 0:02:41.600 Everybody wants us to find it. Yeah, that's right. Today 0:02:41.600 --> 0:02:49.800 on the program, we're going to talk about super symmetry. 0:02:49.840 --> 0:02:55.000 What is it? Not just everyday symmetry, not just good symmetry, 0:02:55.000 --> 0:03:00.520 not just extra symmetry, but super not just mild mannered Tonian, 0:03:01.000 --> 0:03:07.280 superpowered flying symmetry. That's right, supersymmetry. It's supposed to be 0:03:07.320 --> 0:03:09.960 the next big thing in physics. You know. It's motivated 0:03:10.040 --> 0:03:13.880 by looking at the equations and thinking this doesn't quite 0:03:13.960 --> 0:03:16.680 fit together. How can we make this prettier? How can 0:03:16.720 --> 0:03:19.400 we find something that's simpler, that hangs together in a 0:03:19.400 --> 0:03:23.160 way that that satisfies us aesthetically. You know, that's sort 0:03:23.160 --> 0:03:28.480 of surprising how much beauty we search for sometimes in physics. Yeah, 0:03:28.480 --> 0:03:31.560 that's it's kind of interesting that physicists think about beauty 0:03:31.600 --> 0:03:35.040 in their equations, right, Like, isn't that a subjective quality? 0:03:35.640 --> 0:03:39.040 Completely subjective? Absolutely, But you know it's a very important 0:03:39.080 --> 0:03:40.920 guiding principle, Like it goes all the way back to 0:03:40.920 --> 0:03:45.600 Acam's razor. We prefer simple explanations over complex ones. Right, 0:03:45.880 --> 0:03:49.520 If your theory has one moving part, it's simpler than 0:03:49.560 --> 0:03:52.000 something that has two moving parts or ten moving parts. Right. 0:03:52.640 --> 0:03:55.360 Even also just in your life, right, you prefer simpler 0:03:55.400 --> 0:03:58.800 explanations to answer the questions you have. Right, So is 0:03:58.840 --> 0:04:01.240 it more about elegant Do you think like that's an 0:04:01.240 --> 0:04:05.680 elegant solution or an elegant answer in that it's it's 0:04:05.720 --> 0:04:09.200 simple and directly to the point. Yeah, And I think 0:04:09.240 --> 0:04:12.520 it goes to the questions we have as humans. You know, 0:04:12.720 --> 0:04:15.320 I want to know how was the universe put together? 0:04:15.640 --> 0:04:18.200 And I'd love if that answer was short, you know, 0:04:18.520 --> 0:04:21.159 if it was simple. If the answer to the question 0:04:21.240 --> 0:04:23.840 like how is the universe organized is like a huge 0:04:23.960 --> 0:04:26.159 list of what every single particle in the universe is 0:04:26.160 --> 0:04:29.600 supposed to do, then that's not really simplification. Right. In 0:04:29.640 --> 0:04:33.839 some sense, the search for simplicity is inherent. It's core 0:04:33.960 --> 0:04:36.960 to physics, right. That's what physics is is take everything 0:04:37.000 --> 0:04:40.480 we observe and describe in terms of a few equations. Right. Well, 0:04:40.480 --> 0:04:43.599 I mean you're you're basically looking for laws, right, I 0:04:43.600 --> 0:04:46.160 mean that's the idea you know, the idea of a 0:04:46.240 --> 0:04:49.760 law is is something that's applicable to many situations and 0:04:49.800 --> 0:04:53.440 not just specific situations, right, exactly. You want you want 0:04:53.520 --> 0:04:56.360 rules that generalize, Right. You want to measure something here 0:04:56.360 --> 0:04:58.560 and know you can apply it later. You want to say, oh, 0:04:58.640 --> 0:05:01.120 I studied this baseball's ocean, now I know how the 0:05:01.160 --> 0:05:03.440 next baseball is going to move. Right. You don't want 0:05:03.440 --> 0:05:05.520 to a rule that applies a different rule applies to 0:05:05.560 --> 0:05:07.919 every baseball. Yeah, Like you can't have a government that 0:05:08.040 --> 0:05:10.760 runs with a huge book that says, all right, if 0:05:11.000 --> 0:05:13.240 a guy named Whorehead does a podcast and he does 0:05:13.279 --> 0:05:15.200 this and that's not allowed, or if he does this, 0:05:15.320 --> 0:05:17.920 that's not allowed. But then if it's a guy named Daniel, 0:05:17.960 --> 0:05:19.880 then he can't do this or that of that. You 0:05:19.960 --> 0:05:24.040 sort of want rule that applies to a general rule 0:05:24.080 --> 0:05:26.239 that applies to everyone. YEA, Well, you know, I wouldn't 0:05:26.240 --> 0:05:28.680 mind having special rule just for me. Daniel doesn't have 0:05:28.720 --> 0:05:31.680 to pay taxes, Daniel can drive as fast as he likes. 0:05:32.680 --> 0:05:34.560 That would be nice. But you're right, it's not a 0:05:34.560 --> 0:05:37.760 sustainable way to do it. And and it's not just 0:05:37.839 --> 0:05:39.760 not sustainable, you know, I think the whole job of 0:05:39.800 --> 0:05:43.600 physics is to come up with generalizable laws. And so 0:05:43.760 --> 0:05:46.080 we've done this a lot of times in physics. We've said, hey, 0:05:46.120 --> 0:05:50.360 look at this um electricity is kind of similar to magnetism. 0:05:50.400 --> 0:05:53.320 Can we simplify things and describe it in terms of 0:05:53.400 --> 0:05:57.720 just one idea electro magnetism. Oh look, you know this 0:05:57.760 --> 0:06:00.840 piece fits together with that piece. It turns out, you know, 0:06:00.920 --> 0:06:03.159 it's it's all part of the same thing, right, or 0:06:03.200 --> 0:06:06.280 like a discovering F equals m A. And you find 0:06:06.279 --> 0:06:09.000 that this lab applies to a whole bunch of things, 0:06:09.040 --> 0:06:12.359 and it helps you in many many situations, right, yeah, exactly, 0:06:12.440 --> 0:06:14.160 you know, and we do this a lot. We just 0:06:14.200 --> 0:06:16.640 were stumbling over stuff in physics and we don't necessarily 0:06:16.680 --> 0:06:19.560 know what connects to what. So, like, you know, it's 0:06:19.560 --> 0:06:21.800 like finding the front of the elephant, and then a 0:06:21.880 --> 0:06:24.479 hundred years later you discover, oh, elephants have butts too, 0:06:24.520 --> 0:06:26.600 And then finally somebody says, wait, put them together. You 0:06:26.680 --> 0:06:29.040 get a whole animal. Right, it makes much more sense. 0:06:29.240 --> 0:06:32.440 Elephant heads and elephant butts are not separate ideas. Um, 0:06:32.680 --> 0:06:34.200 I want to be the guy, the person who wins 0:06:34.240 --> 0:06:40.760 that Nobel prize the discovery of the elephant but yeah, exactly. 0:06:41.120 --> 0:06:43.640 You can put that on your tombstone. Um. But that's 0:06:43.640 --> 0:06:46.960 the idea, is like connecting different observations that happened to 0:06:47.240 --> 0:06:49.320 you know, happen at different times or different places, and 0:06:49.360 --> 0:06:51.680 realizing they're part of the whole. And so that's the 0:06:51.760 --> 0:06:54.560 driving ideas. Let's look at what we know and look 0:06:54.600 --> 0:06:57.440 for patterns, look for symmetry, symmetries that we can be 0:06:57.520 --> 0:07:01.320 used to simplify things. So that's what this supersymmetry is 0:07:01.320 --> 0:07:05.360 all about. It it's about simplifying the equations of the universe. Right. 0:07:05.480 --> 0:07:08.599 It's like finding like a finding a kind of another 0:07:08.640 --> 0:07:11.600 set of patterns that make it easier to understand or 0:07:11.640 --> 0:07:15.200 easier to um put together right exactly. And it's a 0:07:15.280 --> 0:07:18.680 theoretical exercise, right you say, hey, I notice these patterns 0:07:18.680 --> 0:07:20.440 in the universe, and then you can test that. You 0:07:20.480 --> 0:07:22.680 can say is this pattern real? Is it true? If 0:07:22.720 --> 0:07:25.120 it is, then I expect to find this new particle 0:07:25.160 --> 0:07:29.040 for example. The patterns usually predict something new, and amazingly 0:07:29.240 --> 0:07:31.840 sometimes that works, like that's exactly what happened with the 0:07:31.880 --> 0:07:35.120 Higgs Boson. Higgs and other folks were like, hey, look, 0:07:35.160 --> 0:07:38.080 the universe doesn't quite make sense. This is weird wrinkle 0:07:38.440 --> 0:07:41.320 that wrinkled goes away if you add one more particle, 0:07:41.760 --> 0:07:44.280 and then we actually found the Higgs boson. So like 0:07:44.480 --> 0:07:47.600 this strategy has worked. It's not just like something we 0:07:47.720 --> 0:07:51.240 you know, enjoy doing that has worked, right, Well, it's 0:07:51.280 --> 0:07:54.280 it's a it's a pretty cool word, supersymmetry. And and 0:07:54.320 --> 0:07:56.400 just to be sure, it is one word. Like you 0:07:56.400 --> 0:07:59.560 you don't write superspace symmetry. You write it like Superman. 0:07:59.640 --> 0:08:04.640 It's like supersymmetry. Yeah, we have long meetings about punctuation 0:08:04.680 --> 0:08:07.440 and particle physics, you know, whether to hyphenate where a 0:08:07.440 --> 0:08:09.640 common goes. And because people come from all over the world, 0:08:09.720 --> 0:08:11.680 they have different ideas about how to do this kind 0:08:11.680 --> 0:08:14.880 of stuff. But yeah, we all agree supersymmetry is one word. 0:08:15.200 --> 0:08:18.600 And it's very commonly abbreviated as susie s U s 0:08:18.640 --> 0:08:22.280 WA because supersymmetries were just way too long to say. Right. Well, 0:08:22.280 --> 0:08:24.960 I'm sure a lot of people know susie or two um, 0:08:24.960 --> 0:08:27.400 but we were wondering how many people out there had 0:08:27.480 --> 0:08:31.120 heard of this word supersymmetry. I know, it's basically one 0:08:31.160 --> 0:08:34.400 of the most important motivators for governments to spend billions 0:08:34.440 --> 0:08:37.080 of dollars on an experiment. So you think maybe there 0:08:37.120 --> 0:08:39.360 was a pr campaign, Maybe people know what this is, 0:08:39.400 --> 0:08:42.080 maybe they have an opinion about it. And so, as usual, 0:08:42.240 --> 0:08:44.240 Daniel went out there and ask people in the street 0:08:44.800 --> 0:08:49.120 if they knew what the word supersymmetry means. Here's what 0:08:49.200 --> 0:08:51.960 people had to say. Yeah, I've heard about it, but 0:08:52.000 --> 0:08:53.840 I don't know what it is. I've heard about it 0:08:53.880 --> 0:08:58.080 in some lectures I was listening to from from from 0:08:58.200 --> 0:09:02.800 Fineman I think, and Paul to Rock No no idea. 0:09:03.400 --> 0:09:06.480 Who would you guess just from the name, I would 0:09:06.480 --> 0:09:10.199 have to do something symmetrical, thanks very much from Big 0:09:10.240 --> 0:09:13.040 Bang Theory Ya from the TV show. Just heard it, 0:09:13.120 --> 0:09:14.719 but I don't really know what it means to be. 0:09:15.000 --> 0:09:17.640 To guess, what do you think big supersymmetry might be? 0:09:18.320 --> 0:09:21.360 Probably has to do with symmetry and how you make 0:09:21.480 --> 0:09:24.640 things easier in science, probably because usually like everything that 0:09:24.720 --> 0:09:26.679 symmetrical makes it easier because you can divide and a 0:09:26.720 --> 0:09:29.560 half when it's too geometry, or it's just like easier 0:09:29.559 --> 0:09:33.079 to apply some rules and equations on it. So I 0:09:33.080 --> 0:09:35.680 guess it would just be like a simplification of something 0:09:35.720 --> 0:09:39.720 really complicated. Okay, awesome, I don't know what that means. 0:09:39.720 --> 0:09:43.840 But my guess is like something about math, like thanks 0:09:43.960 --> 0:09:48.319 very much, assumes something is symmetrical, or like something is 0:09:48.360 --> 0:09:51.480 like balanced, or even maybe no, no, never, no, I 0:09:51.520 --> 0:09:52.800 don't have to guess what it might be. What do 0:09:52.800 --> 0:09:59.080 you think it might be symmetrical? So, as usual, the 0:09:59.160 --> 0:10:03.120 Big Bang Theory has educated Americans and what a word 0:10:03.440 --> 0:10:07.000 is without explaining what it actually means. I bet you 0:10:07.000 --> 0:10:09.640 plus love and hate that show like you probably you 0:10:09.640 --> 0:10:12.480 probably don't love the writing or the way that physicists 0:10:12.480 --> 0:10:14.720 are portrayed. But at the same time, you know, it's 0:10:14.720 --> 0:10:17.800 sort of educated so many people in the words and 0:10:17.840 --> 0:10:20.240 the kind of maybe a little bit of the concepts 0:10:20.320 --> 0:10:23.600 in particle physics. Right right as they're laughing and making 0:10:23.600 --> 0:10:27.800 fun of physicists, they accidentally learned a few pieces of vocabulary. 0:10:27.960 --> 0:10:29.640 There is a positive side of that. You're right, you 0:10:29.640 --> 0:10:32.880 wouldn't You wouldn't let people laugh at you too if 0:10:32.920 --> 0:10:36.440 they ended up learning something. Isn't that the premise of 0:10:36.480 --> 0:10:41.000 this entire podcast? Listen laugh learn something? Anyway? Well, there 0:10:41.040 --> 0:10:44.599 you go. You're right up there with Sheldon and and 0:10:45.000 --> 0:10:46.840 I don't even even know the other characters. But no, no, 0:10:46.880 --> 0:10:49.440 I would totally humiliate myself if everybody in the world 0:10:49.520 --> 0:10:52.000 could learn a little bit more physics. Whatever you want, 0:10:52.200 --> 0:10:54.040 you want to do a dunk tank, you want me 0:10:54.040 --> 0:10:56.920 to wear a silly costume, sign me up on man. 0:10:57.000 --> 0:11:00.640 That should totally be our live traveling show for this podcast. 0:11:01.200 --> 0:11:04.120 You have a dunk tank with like if you answer 0:11:04.160 --> 0:11:06.719 a physics question correctly, you get the dunk Daniel with. 0:11:07.640 --> 0:11:10.959 You have like a short Anger's dunk tank. You know, oh, 0:11:11.080 --> 0:11:13.800 like is he dunked or is he not done? Behind 0:11:13.800 --> 0:11:16.920 a cave with like a box and people throw things 0:11:16.960 --> 0:11:20.000 and then it's all connected to some quantum particle and 0:11:20.040 --> 0:11:22.280 you may or may not get wet mm hmm. So 0:11:22.320 --> 0:11:24.520 I guess that will be my sacrifice for the art. Right, 0:11:24.559 --> 0:11:26.880 That's how I'm going to make sure that I'm suffering 0:11:27.160 --> 0:11:30.320 for our art. Right. That's good because my creative partner 0:11:30.360 --> 0:11:33.480 is a joy to worker. Good. He sounds like a 0:11:33.559 --> 0:11:43.760 nice guy. He's an amazing, amazing um anyway. But yeah, 0:11:43.800 --> 0:11:46.120 so not a lot of people have heard of the concept. 0:11:46.160 --> 0:11:48.920 I mean, everyone knows what super beans, and I imagine 0:11:48.920 --> 0:11:51.240 a lot of most people out there know what symmetry means. 0:11:51.280 --> 0:11:53.360 But when you put it together, suddenly it's a it's 0:11:53.400 --> 0:11:55.800 a new word, right. Yeah. You could hear people trying 0:11:55.800 --> 0:11:57.679 to figure it out on the fly, speculating what it 0:11:57.800 --> 0:12:00.920 might mean based on zero knowledge and just the atomology. 0:12:01.400 --> 0:12:05.200 And yeah, so nobody had an idea supersymmetry needs to 0:12:05.200 --> 0:12:07.520 be better sold, right right, Well, let's get into it 0:12:07.520 --> 0:12:10.000 all right, um, And for me, you know, I think 0:12:10.040 --> 0:12:12.280 we just let's talk about what symmetry means in the 0:12:12.280 --> 0:12:14.680 first place. I mean, I know that in the common usage, 0:12:14.760 --> 0:12:17.320 symmetry just means that it's kind of like a like 0:12:17.360 --> 0:12:20.760 a mirror image, like something symmetrically something else. If it's 0:12:20.800 --> 0:12:23.560 if it looks the same as if you were looking 0:12:23.559 --> 0:12:26.760 at it in a mirror. Right. Yeah. It's all about patterns, right, 0:12:27.240 --> 0:12:30.920 is can you do two things look similar? Right? And Um? 0:12:31.440 --> 0:12:34.560 For particles, we find a lot of these patterns among 0:12:34.559 --> 0:12:37.240 the particles. And what we do is we instead of 0:12:37.280 --> 0:12:39.800 thinking about the individual particles the way you were talking 0:12:39.800 --> 0:12:42.560 about individual laws for each person, we try to think 0:12:42.600 --> 0:12:45.560 about the particles together in groups. So for example, you 0:12:45.600 --> 0:12:48.600 have the electron, and then you have the electrons, antiparticle, 0:12:48.679 --> 0:12:51.840 the positron. Right, we don't really think about the electron 0:12:51.840 --> 0:12:54.520 and the positron is separate particles. We think about the 0:12:54.720 --> 0:12:57.040 we think of them as two sides of a coin, right, 0:12:57.240 --> 0:13:00.760 the positive and negative version of this part particle, and 0:13:00.840 --> 0:13:02.880 we think of it as one concept. It's kind of 0:13:02.920 --> 0:13:05.520 like a it's the same except you flip a sign 0:13:05.960 --> 0:13:07.680 or you know. It's kind of like if you you 0:13:07.679 --> 0:13:09.439 put them electron in front of the mirror, one of 0:13:09.480 --> 0:13:11.560 them would be spinning one way, either one would be 0:13:11.600 --> 0:13:14.320 spinning kind of the other way. Right. Yeah, it's like 0:13:14.360 --> 0:13:16.959 you don't think about the heads separately from the tails 0:13:16.960 --> 0:13:18.840 of a coin, right, There just different sides of the 0:13:18.880 --> 0:13:22.240 same coin, literally, And we think about particles the same way. 0:13:22.400 --> 0:13:26.160 And because every particle seems to have an antiparticle, you know, 0:13:26.200 --> 0:13:29.000 with some funny exceptions like the photon, that it's a 0:13:29.120 --> 0:13:33.480 very useful strategy. We notice this relationship between positrons and electrons, 0:13:33.520 --> 0:13:36.240 between muans and anti muons, and so that's a really 0:13:36.280 --> 0:13:39.679 important symmetry and it it helps us ask questions. Right, 0:13:39.679 --> 0:13:42.200 We're like, well, why is there this symmetry? What does 0:13:42.280 --> 0:13:45.560 it mean? We think it reveals something deep about the universe. 0:13:45.679 --> 0:13:47.280 We still don't know the answer to that one, right, 0:13:47.320 --> 0:13:50.600 Like why do particles have antiparticles. We have no idea, 0:13:50.920 --> 0:13:54.440 but I think it's an important clue about something fundamental 0:13:54.440 --> 0:13:56.960 about the universe. So we're always looking for these patterns, 0:13:57.280 --> 0:13:59.960 not just because it helps us simplify and right thing 0:14:00.120 --> 0:14:02.640 down more quickly, but because we were hopeful that their 0:14:02.679 --> 0:14:06.280 clues about what's going on on the deeper level. Right. So, okay, 0:14:06.280 --> 0:14:08.840 so that's what symmetry means. It's it's kind of like 0:14:08.920 --> 0:14:12.920 um an electron having a mirror image of itself called 0:14:12.960 --> 0:14:15.680 the anti electron. That's right. But symmetry works in lots 0:14:15.679 --> 0:14:18.439 of different ways, like there are other symmetries in particle physics. 0:14:18.880 --> 0:14:21.000 If you remember the episode where we introduced sort of 0:14:21.000 --> 0:14:24.120 the standard model, the electron has the anti electron, but 0:14:24.280 --> 0:14:27.520 also has symmetries in other ways, Like there's the mun 0:14:27.960 --> 0:14:30.800 and the taw. These particles are exactly the same as 0:14:30.840 --> 0:14:34.400 the electron, but they're heavier, right, So the electron has 0:14:34.520 --> 0:14:37.240 two kinds of symmetries. That's a symmetry as well, But 0:14:37.280 --> 0:14:39.440 they're not they're not like they don't weigh the same, 0:14:39.720 --> 0:14:41.800 they just sort of act the same, that's right. There 0:14:41.880 --> 0:14:44.160 is a difference, right, So they're not the identical particle. 0:14:44.160 --> 0:14:46.440 But there's a pattern there because the electron is not 0:14:46.480 --> 0:14:49.560 the only one with too heavier cousins, right, The neutrino 0:14:49.680 --> 0:14:52.600 is too heavier cousins. The up coork has too heavier cousins, 0:14:52.720 --> 0:14:55.760 the down cork is too heavier cousins. There's something going 0:14:55.840 --> 0:14:59.440 on where every particle has two heavier versions of itself. 0:14:59.720 --> 0:15:03.480 We call the flavors. Sometimes, because we're not great in 0:15:03.520 --> 0:15:07.400 particle physics about coming with new names, adopt an existing word, 0:15:08.120 --> 0:15:11.120 which is very confusing. Wait, so that's that's a symmetry 0:15:11.160 --> 0:15:14.000 as well, these kind of heavier versions of an electron. 0:15:14.520 --> 0:15:18.400 Those are absolutely really what how is that symmetric? Because 0:15:18.400 --> 0:15:21.520 you know it imagine symmetry means like the same or 0:15:21.560 --> 0:15:24.080 mirror image. Yeah, it's just you have to change your 0:15:24.080 --> 0:15:26.600 definition of what the mirror means. Right. So in the 0:15:26.640 --> 0:15:30.200 case of positive and negative electrons, your mirror is changing 0:15:30.200 --> 0:15:33.080 the charge, right, it's changing from positive to negative. But 0:15:33.160 --> 0:15:35.840 that mirror can have lots of different kinds of reflections. 0:15:35.960 --> 0:15:38.520 Right in this case, an electron and a muon and 0:15:38.560 --> 0:15:41.160 a town. We think of its just different varieties of 0:15:41.200 --> 0:15:43.640 the same kind of particle. So sort of like a 0:15:43.680 --> 0:15:47.040 three way mirror. These particles are definitely related. Right, an 0:15:47.040 --> 0:15:49.960 electron is much more close relationship with the muon than 0:15:49.960 --> 0:15:53.040 it does with like corks. But why why do you 0:15:53.080 --> 0:15:55.280 call it a symmetry? Is it in the equation? Something 0:15:55.320 --> 0:15:58.440 about the equations that somehow you know what I mean? 0:15:58.800 --> 0:16:01.640 You can write all those particles, all those particles have 0:16:01.680 --> 0:16:03.880 the same kinds of interactions, right, they interact with the 0:16:03.920 --> 0:16:06.520 same forces. Uh, they interact with the forces in very 0:16:06.560 --> 0:16:09.240 similar ways. And so when you write down the equations, 0:16:09.280 --> 0:16:12.560 instead of writing down here, how here's how an electron works, 0:16:12.760 --> 0:16:15.240 Here's how a mun works, Here's how a tow works. 0:16:15.240 --> 0:16:17.760 Here the laws for those particles, we just write down 0:16:17.800 --> 0:16:19.960 one set of laws because they follow the same laws. 0:16:20.160 --> 0:16:21.840 There's a little bit of a difference. Each one has 0:16:21.840 --> 0:16:24.840 a different mass, right, but the laws, the basic structure 0:16:24.880 --> 0:16:27.040 of how it works is the same. Is it kind 0:16:27.080 --> 0:16:30.560 of like different solutions to the same equation? Or Well, 0:16:30.560 --> 0:16:32.320 what we don't know is why we have them, right, 0:16:32.320 --> 0:16:35.920 you're sort of suggesting like the reason we have three, right, Well, 0:16:35.960 --> 0:16:37.640 we don't know the answer to that. We don't know 0:16:37.680 --> 0:16:39.800 why there is more than one at all, Like why 0:16:39.840 --> 0:16:42.400 does this symmetry exist? And then we don't know why 0:16:42.400 --> 0:16:45.120 there are three in a four or seven or two. Right, 0:16:45.520 --> 0:16:49.040 those are deep questions. When you discover symmetry, it's helpful because, 0:16:49.040 --> 0:16:51.640 as we said, it gives you a clue about some 0:16:51.720 --> 0:16:54.000 deep questions, but doesn't always give you the answer, right, 0:16:54.240 --> 0:16:56.640 sort of raises the question. So in this case, when 0:16:56.680 --> 0:16:59.400 when you say symmetry, you kind of mean like an 0:16:59.400 --> 0:17:03.360 imperfect copy. Yeah, exactly, and the perfection there can vary, right, 0:17:03.400 --> 0:17:06.399 Like the positron of the electron are really exactly the 0:17:06.440 --> 0:17:09.760 same except for the charge um. In the case of 0:17:09.800 --> 0:17:12.919 the electron, the mu and the too, they're very similar. 0:17:12.960 --> 0:17:16.040 There are some differences, the most important one is the mass. 0:17:16.440 --> 0:17:18.719 So you can have more or less perfect symmetries. None 0:17:18.760 --> 0:17:21.959 of these symmetries are exact, so just sort of like 0:17:22.040 --> 0:17:25.520 guiding patterns that we used to organize how how we 0:17:25.560 --> 0:17:27.960 write down the equations. Okay, so if you had to, 0:17:28.040 --> 0:17:31.920 if you had to christen this thing another name, would 0:17:31.920 --> 0:17:34.160 you still call it some symmetry or would you maybe 0:17:34.200 --> 0:17:36.680 use another word? Oh? I think symmetry is a nice word. 0:17:36.680 --> 0:17:39.800 You know, symmetry shows like aesthetic purity, right, I mean, 0:17:39.800 --> 0:17:42.560 when you're looking at art, you like symmetry. But when 0:17:42.560 --> 0:17:45.040 you look at a face. Scientists have like discovered right 0:17:45.080 --> 0:17:47.879 that symmetric faces are considered the most beautiful. So I 0:17:47.880 --> 0:17:51.120 think there's a connection between symmetry and beauty and simplicity. 0:17:51.240 --> 0:17:53.600 So I like the word symmetry. Yeah, No, I think 0:17:53.600 --> 0:17:56.800 it's it's pretty nice. It's hard to spell for her 0:17:56.880 --> 0:17:59.520 young students. I've I've seen a creatively spelled in lots 0:17:59.520 --> 0:18:03.000 of different way is. But it's a nice word. Well, 0:18:04.200 --> 0:18:06.080 hold on, I'm still stuck a little bit in symmetry. 0:18:06.119 --> 0:18:10.760 So why is symmetry Plano mild manner symmetry? Why is 0:18:10.800 --> 0:18:14.679 that um important in the equations of physics because you 0:18:14.760 --> 0:18:17.359 see it or it's it's something that helps you solve 0:18:17.440 --> 0:18:19.919 the equations. Well, it's for the same reason that you 0:18:20.080 --> 0:18:23.240 um you said earlier about like writing laws. You wouldn't 0:18:23.240 --> 0:18:26.199 want to write down a different law for everybody. You'd notice, Hey, 0:18:26.240 --> 0:18:28.000 I'm rinning now all the same laws, except I'm just 0:18:28.040 --> 0:18:31.800 substituting Jorge some places and Daniel in other places. Maybe 0:18:31.880 --> 0:18:34.880 I should just write one law for everybody, right, And 0:18:34.960 --> 0:18:37.120 so that's what we're doing with symmetries, is we're trying 0:18:37.119 --> 0:18:40.120 to find these patterns to simplify things. We could say, hey, look, 0:18:40.119 --> 0:18:42.240 the same laws apply to the electron and the muan 0:18:42.359 --> 0:18:44.520 and the tow. We just need to tweak this a 0:18:44.560 --> 0:18:47.879 little bit, and the same rules apply. So that's what 0:18:47.920 --> 0:18:50.360 we're going for. Maybe, Okay, So maybe when you when 0:18:50.359 --> 0:18:53.760 you say symmetry, you actually means like same rules apply. Yeah, 0:18:54.119 --> 0:18:55.800 Or you could think of it like a pattern, right, 0:18:55.960 --> 0:18:57.880 all right, So it's kind of like you might say, 0:18:57.920 --> 0:19:00.119 like a living in the US is very symmetric to 0:19:00.240 --> 0:19:03.360 living in Suitland in that blah blah blah blah blah 0:19:03.359 --> 0:19:06.320 blah blah, and it's kind of like it's it's the 0:19:06.359 --> 0:19:09.240 magrick thing that it's sort of like the same rules apply, 0:19:09.359 --> 0:19:11.200 or there's some sort of pattern between living here in 0:19:11.240 --> 0:19:13.160 the vein in Switzerland. Yeah. I don't know if there's 0:19:13.240 --> 0:19:15.840 much in common between living in Switzerland living in the US. 0:19:16.040 --> 0:19:19.280 I've lived in both places. They're pretty different experiences. Um, 0:19:19.320 --> 0:19:23.439 I guess they both eat yogurt. Super symmetric. It's not 0:19:23.480 --> 0:19:26.720 a super symmetric analogy, Daniel, Exactly right. That was not 0:19:26.760 --> 0:19:31.560 a super analogy about symmetry. It's an underwhelming symmetry, yeah, exactly. 0:19:31.800 --> 0:19:34.080 But you know, you could look for example, what are 0:19:34.080 --> 0:19:36.760 the laws of different countries, And you might say, hey, look, 0:19:37.160 --> 0:19:40.399 there is these underlying things everybody wants to the value 0:19:40.400 --> 0:19:43.320 of property and everyone who wants life, and everyone wants liberty, 0:19:43.359 --> 0:19:45.840 and you could say those are inherent about being human. 0:19:45.960 --> 0:19:49.200 Is something about forming a human society that makes people 0:19:49.240 --> 0:19:52.040 want these things, and so we should encode those as 0:19:52.080 --> 0:19:54.640 the bedrock principles of humanity. Right, so we call those 0:19:54.720 --> 0:19:58.280 human rights. You so and and and you've learned something 0:19:58.320 --> 0:20:01.720 about humanity that way by identifying in these core principles. Right. 0:20:01.760 --> 0:20:03.479 So it's kind of like a perspective. It's like when 0:20:03.520 --> 0:20:05.800 you say you want the laws of physics to be symmetric, 0:20:05.920 --> 0:20:09.760 you're saying you want them to be kind of a universal, 0:20:09.800 --> 0:20:13.160 and you want them to be applicable to many different things, 0:20:13.240 --> 0:20:17.520 and you want them to not very on a Willie 0:20:17.520 --> 0:20:21.200 Neely basis, wanted to be kind of rock solid. Yeah, exactly. 0:20:21.359 --> 0:20:24.120 Symmetries allow us to write these things more compactly, write 0:20:24.119 --> 0:20:27.560 to write down fewer laws because we identify patterns and 0:20:27.600 --> 0:20:31.399 so the same laws can apply to different kinds of phenomena. Right, Okay, 0:20:31.400 --> 0:20:35.960 So that's kind of regular mild manner. Clark Kent glasses wearing. 0:20:36.000 --> 0:20:39.399 Symmetry is some sort of like a perspective on the 0:20:39.480 --> 0:20:42.360 laws of physics that say that it's, um, it's sort 0:20:42.400 --> 0:20:45.800 of applicable everywhere. So then um, but now they're supersymmetry. 0:20:45.800 --> 0:20:48.320 Are you ready to put spandex on the look like 0:20:48.359 --> 0:20:52.000 the clothes off and see what he's wearing underneath? When 0:20:52.080 --> 0:20:56.080 making a family friendly podcast, Well, he's taking his clothes up, 0:20:56.080 --> 0:20:58.760 but he's got an outfit on underneath. Folks. Okay, well 0:20:58.760 --> 0:21:15.520