WEBVTT - What is Bose Einstein Condensate 0:00:08.440 --> 0:00:11.440 Hey, Jorney, do you know who is the first person 0:00:11.520 --> 0:00:16.759 to reach the South Pole? It's probably a Norwegian, wasn't 0:00:16.760 --> 0:00:20.439 it someone called rolled Emson. Yeah, he's pretty famous. But 0:00:20.920 --> 0:00:24.279 do you know who the second or third place finishes were. 0:00:25.360 --> 0:00:30.479 I'm gonna guess rold Emonson Jr. Or rold Emonson the third. 0:00:30.920 --> 0:00:33.720 I have no idea. You know, those people who came 0:00:33.760 --> 0:00:37.080 in second and third, they risked their lives, literally froze 0:00:37.080 --> 0:00:39.519 their butts off, and we don't even know who they are. 0:00:39.720 --> 0:00:42.440 Man in this case, it was literally a raised to 0:00:42.640 --> 0:00:46.600 the bottom of the world. But yeah, you're right, I 0:00:46.640 --> 0:00:49.240 guess second place doesn't get much attention. And the same 0:00:49.360 --> 0:00:52.839 is true in science. There's no consolation prize for the Nobel. 0:00:53.040 --> 0:00:56.600 You don't get a silver Noble price. They should hand 0:00:56.600 --> 0:00:59.840 out a silver and a bronze, an honorable mention. There 0:01:00.120 --> 0:01:17.600 just an honor to be nominated. Hi, I'm or Hamming 0:01:17.680 --> 0:01:21.319 cartoonists and the creator of PhD comments. Hi I'm Daniel. 0:01:21.440 --> 0:01:23.800 I'm a particle of physicist. And if I was in 0:01:23.840 --> 0:01:25.680 the running for the Nobel Prize, I wouldn't get the 0:01:25.720 --> 0:01:29.040 silver or le bronze. I would get the Plywood Nobel Prize. 0:01:29.080 --> 0:01:33.240 You get the thanks for Trying coupon, I get the 0:01:33.319 --> 0:01:35.840 pin and ribbon on him and say thanks. Welcome to 0:01:35.880 --> 0:01:38.800 our podcast, Daniel and Jorge Explained the Universe, a production 0:01:38.880 --> 0:01:41.200 of I Heart Radio in which we take a tour 0:01:41.280 --> 0:01:44.000 of all the incredible things that scientists have won the 0:01:44.000 --> 0:01:47.640 Nobel Prize for and dive deep into all the things 0:01:47.680 --> 0:01:50.800 that science has not yet figured out, all the things 0:01:50.800 --> 0:01:54.000 that people want to understand, all those weird mysteries of 0:01:54.000 --> 0:01:57.360 the universe that nobody has yet figured out. Because it's 0:01:57.400 --> 0:02:01.120 a big, mysterious universe out there and humans are trying 0:02:01.120 --> 0:02:03.160 to make sense of it and come up with theories 0:02:03.160 --> 0:02:05.800 about how it all works. But it is, after all 0:02:05.880 --> 0:02:10.359 a human endeavor, and so it's about humans chipping away 0:02:10.480 --> 0:02:12.960 at the big unknown questions of the universe. And here 0:02:13.000 --> 0:02:15.359 on the show, we like to talk about the smallest things. 0:02:15.400 --> 0:02:18.440 We like to break open the universe and find out 0:02:18.480 --> 0:02:20.600 what it's made out of. What are the smallest things. 0:02:20.800 --> 0:02:24.440 But another sort of orthogonal way to approach discovery is 0:02:24.480 --> 0:02:28.079 trying to make matter do weird stuff like you're familiar 0:02:28.120 --> 0:02:32.040 with three states of matter, solids, liquids in gases, But 0:02:32.080 --> 0:02:34.880 it turns out there are lots of other really weird 0:02:34.960 --> 0:02:38.800 things that matter can do. Yeah, there are other states 0:02:38.800 --> 0:02:42.600 of matter like super hot forms like plasma, and also 0:02:42.800 --> 0:02:47.200 super cold forms. And one of these forms is a 0:02:47.200 --> 0:02:49.720 pretty well known form that we're going to talk about today. 0:02:49.840 --> 0:02:52.760 That's right. If you get matter into really weird configurations, 0:02:52.800 --> 0:02:55.000 it will do strange stuff. And this is a great 0:02:55.000 --> 0:02:57.280 way to learn about what the rules are, how does 0:02:57.320 --> 0:03:00.000 it fit together, what are the forces that are involved? 0:03:00.440 --> 0:03:03.359 And it's just fun to make matter be weird. Can 0:03:03.400 --> 0:03:05.520 you make it shinye? Can you make it jump? Can 0:03:05.560 --> 0:03:08.760 you make it super conducting? Can you make it super fluid? 0:03:09.000 --> 0:03:11.600 Can you make it act as a single blob? It's 0:03:11.600 --> 0:03:13.600 fun to make new kinds of Google, would that be 0:03:13.600 --> 0:03:17.640 your bumper sticker, Daniel? Keep matter weird, yeah, because one 0:03:17.680 --> 0:03:19.640 of the basic ways to explore the universe is just 0:03:19.680 --> 0:03:21.640 to look around you and see, like what kinds of 0:03:21.680 --> 0:03:24.320 stuff is there? You know, the very first people to 0:03:24.400 --> 0:03:27.000 think about what is the universe made out of just 0:03:27.160 --> 0:03:30.120 sort of organized the stuff around them into like you know, 0:03:30.240 --> 0:03:33.760 air or fire, earth and water. And that's reflection that 0:03:33.800 --> 0:03:37.240 there are different kinds of things. And even though we 0:03:37.320 --> 0:03:40.040 know that the universe has made fundamentally of tying the 0:03:40.080 --> 0:03:44.120 little particles. Those particles come together in really weird ways. 0:03:44.200 --> 0:03:47.720 I mean, who could predict solids and gases and all 0:03:47.760 --> 0:03:51.440 sorts of weird behavior from just the tiny particles. It's complicated. 0:03:51.480 --> 0:03:53.720 So while it's worthwhile to like dig down deep to 0:03:53.720 --> 0:03:56.560 the tiny bits, it's also really worthwhile to figure out 0:03:56.640 --> 0:03:59.640 how those bits play together to make weird stuff. So 0:03:59.720 --> 0:04:06.600 to the the program will be asking the question, what 0:04:06.880 --> 0:04:11.440 is a Bose Einstein condensate now? M Daniel, I'm guessing 0:04:11.480 --> 0:04:16.200 that's not related to both speakers or being like a BOWS. 0:04:17.000 --> 0:04:19.200 I think Bose was an early investor in the Bows 0:04:19.240 --> 0:04:25.760 speaker system. They're not related. The Bose family fortune came 0:04:25.760 --> 0:04:28.360 from physics. No, but they are related to the Higgs boson. 0:04:28.880 --> 0:04:32.479 It's the same Bows, is it? Yeah? Yes, absolutely, the 0:04:32.520 --> 0:04:35.480 Bose Einstein condensate is related to the Higgs boson. It's 0:04:35.520 --> 0:04:39.360 the same. Bows is a famous Indian physicist whose last 0:04:39.440 --> 0:04:42.279 name is Bose, and the kind of particle that we 0:04:42.320 --> 0:04:44.800 call a boson, a particle of spin one, is named 0:04:44.800 --> 0:04:48.000 after both. And he's also the guy who worked together 0:04:48.040 --> 0:04:50.160 with Einstein to come up with this idea of a 0:04:50.160 --> 0:04:54.080 weird state of matter called the Bose Einstein content. So 0:04:54.240 --> 0:04:57.160 he did rocket leg a ball And I don't know 0:04:57.200 --> 0:04:59.719 if you remember, but after the Higgs boson was discovered, 0:05:00.040 --> 0:05:02.440 there are a lot of folks in India who are like, hey, 0:05:02.480 --> 0:05:04.720 how come Higgs is getting all the credit? After all? 0:05:05.040 --> 0:05:08.159 What about bos is important contribution? His name is half 0:05:08.200 --> 0:05:12.720 of Higgs boson. Why isn't he getting as much credit? Wow? 0:05:12.760 --> 0:05:16.000 I guess it's lots of brand appealed, like clean X. Yeah. Well, 0:05:16.000 --> 0:05:17.839 if you're gonna get your name on stuff, you know, 0:05:17.880 --> 0:05:20.680 you can get your name on one individual particle like Higgs, 0:05:21.040 --> 0:05:22.679 or you can get your name on like a whole 0:05:22.880 --> 0:05:27.760 class of particles like bosons. Bosons are anything with integer spin. 0:05:28.040 --> 0:05:31.640 That's like half the particles out there, photons, w's, z 0:05:31.920 --> 0:05:36.200 s all these are boson particles. Right. Well, so today 0:05:36.320 --> 0:05:38.479 this is about states of matter, and you're right, it 0:05:38.600 --> 0:05:40.839 is kind of interesting that, you know, we can talk 0:05:40.839 --> 0:05:43.839 about what matter is and what it does and what 0:05:43.960 --> 0:05:45.600 it looks like, but we can also talk about the 0:05:45.640 --> 0:05:48.520 ways it can form itself or the ways that it 0:05:48.640 --> 0:05:51.560 can exist out there. Yeah, and it's incredible that we 0:05:51.600 --> 0:05:54.120 can sometimes predict this. We can just like write down 0:05:54.240 --> 0:05:56.719 math on a piece of paper and say, we think 0:05:56.800 --> 0:05:59.760 if you put these atoms in this weird configuration that 0:06:00.160 --> 0:06:03.720 do this amazing, crazy thing you can't otherwise see. And 0:06:03.760 --> 0:06:06.279 then it's a game of seeing whether you can do it. 0:06:06.400 --> 0:06:09.160 You know, it's an experimental challenge. And this is one 0:06:09.200 --> 0:06:12.600 of those stories where the theorists were decades and decades 0:06:12.680 --> 0:06:15.720 ahead of the experimentalists. They had this idea in the 0:06:15.800 --> 0:06:19.279 twenties and it wasn't until the nineties that people figured 0:06:19.320 --> 0:06:21.440 it out. That means that it was one of these 0:06:21.480 --> 0:06:25.320 like plums hanging out there where everybody knew if you 0:06:25.360 --> 0:06:27.120 could be the first one to do it, you would 0:06:27.120 --> 0:06:29.360 get a Nobel Prize. And there was sort of like, 0:06:29.600 --> 0:06:32.159 you know, progress for ten years, and then things ground 0:06:32.160 --> 0:06:34.040 to a halt. Nobody had any good ideas, and then 0:06:34.040 --> 0:06:36.960 I burst a progress and then very late in the game, 0:06:37.240 --> 0:06:40.120 a quick sprint to the finish line, where you know, 0:06:40.160 --> 0:06:42.440 the people who crossed the finish line first, they win 0:06:42.480 --> 0:06:45.640 the Nobel Prize and everybody else just has a cold 0:06:45.720 --> 0:06:49.159 gas of atoms man. So only two people are famous, 0:06:49.240 --> 0:06:51.080 the people who come up with a problem and the 0:06:51.120 --> 0:06:53.880 people who solve the problem. Everyone in between gets forgot 0:06:54.400 --> 0:06:57.040 that's right. And if you find this kind of story inspiring, 0:06:57.040 --> 0:06:59.599 you know, there are plenty of other things out there 0:06:59.600 --> 0:07:02.520 which everybody knows. If you discover them, you would win 0:07:02.520 --> 0:07:05.640 a Nobel Prize. And maybe we're five years, maybe we're 0:07:05.640 --> 0:07:08.520 fifty years away from discovering those things and somebody getting 0:07:08.560 --> 0:07:11.640 the Nobel Prize. But there is plenty of low hanging 0:07:11.680 --> 0:07:14.080 fruit left in physics. All right, are you making a 0:07:14.120 --> 0:07:17.320 plug for bananas, Daniel, because they're pretty low hanging In general, 0:07:19.320 --> 0:07:25.360 people have discovered bananas already, sorry to first bubble well, 0:07:25.640 --> 0:07:28.440 such as the case for the Bose Einstein concent And 0:07:28.440 --> 0:07:30.280 as usually, we were wondering how many people out there 0:07:30.360 --> 0:07:33.720 knew what this was or where familiar with what the 0:07:33.840 --> 0:07:36.400 state of matter is, And so as usual, Daniel went 0:07:36.480 --> 0:07:39.000 out there into the wilds of the internet to ask 0:07:39.040 --> 0:07:42.840 people what is a Bose Einstein concent That's right? And 0:07:42.880 --> 0:07:45.560 if you'd like to participate in our random person on 0:07:45.600 --> 0:07:49.000 the Internet questions, please write to us two questions at 0:07:49.080 --> 0:07:51.720 Daniel and jorgean dot com. We would love to hear 0:07:51.800 --> 0:07:54.840 your thoughts for future upcoming episodes. Here's what people had 0:07:54.880 --> 0:07:58.120 to say. I would imagine something to do with Albert Einstein, 0:07:58.360 --> 0:08:00.120 though I don't think it has anything to do with 0:08:00.200 --> 0:08:03.040 Bose audio. I would guess it might have something to 0:08:03.080 --> 0:08:08.360 do with Bosn's and condensate means, maybe something with the 0:08:08.400 --> 0:08:12.400 way they behave at a particular temperature or pressure. Maybe 0:08:12.440 --> 0:08:14.720 it's a speaker of the vibrates water out of the 0:08:14.800 --> 0:08:18.200 year and then use the hydrogen to blow up your house. Well, 0:08:18.240 --> 0:08:23.200 I heard about it, but I don't remember. It's some 0:08:23.360 --> 0:08:28.120 kind of state or I don't know. I think Bose 0:08:28.360 --> 0:08:31.280 was a fellow that was around before Einstein who came 0:08:31.360 --> 0:08:33.760 up with the initial concept, and then I think Einstein 0:08:33.880 --> 0:08:36.640 sweetened the deal a little bit. But this was around 0:08:36.840 --> 0:08:41.280 something hectic to do with theory of relativity and the 0:08:41.360 --> 0:08:45.079 expansion of the universe and universal constants, So I think 0:08:45.120 --> 0:08:48.120 it was something related to that, but I can't quite remember. 0:08:48.120 --> 0:08:50.480 I know it was mentioned on the podcast recently. It 0:08:50.640 --> 0:08:54.760 was the state of matter, I think from dron The 0:08:54.800 --> 0:08:56.800 scientists in the s S lab found it in some 0:08:57.120 --> 0:09:00.760 udom cold lab that in the one name and they 0:09:00.800 --> 0:09:04.840 discoded it's been theoretical so far, and so first them 0:09:04.840 --> 0:09:08.640 there's something you exist in that state of matter? All right, Well, 0:09:08.679 --> 0:09:10.800 it sounds like a lot of people knew was a 0:09:10.840 --> 0:09:13.560 state of matter. Yeah, except for the folks who thought 0:09:13.559 --> 0:09:15.960 it was a speaker that vibrates water out of the 0:09:15.960 --> 0:09:19.120 air and blows up your house. Wow. Where did that 0:09:19.160 --> 0:09:21.680 one come from? Right? I don't know. That must have 0:09:21.679 --> 0:09:24.719 been like an awesome installation of massive bows speakers that 0:09:24.800 --> 0:09:27.920 chattered somebody's windows or something, And I like somebody made 0:09:28.000 --> 0:09:31.080 that connection to the Boson particle. Yeah, exactly. So there's 0:09:31.080 --> 0:09:34.560 some good general knowledge out there. Good job listeners. Yeah, 0:09:34.720 --> 0:09:38.120 so bose, Einstein, condensate, Daniel, let's dig into it. What 0:09:38.240 --> 0:09:40.679 is it? I'm guessing it has something to do with 0:09:40.880 --> 0:09:46.120 Einstein and maybe condensed milk? Is that the sweet and 0:09:46.200 --> 0:09:50.480 condensed milk? Yes, it's a recipe for lemon bars by 0:09:50.480 --> 0:09:54.360 Boz and only if you get it cold enough and 0:09:54.440 --> 0:09:56.880 only the first bite. Yeah. So what it is is 0:09:56.920 --> 0:10:00.000 a new state of matter, another state of matter different 0:10:00.040 --> 0:10:04.160 and from liquid, solid, or gas or even plasma. And 0:10:04.200 --> 0:10:06.840 as you said before, those are the states of matter 0:10:06.920 --> 0:10:12.680 sort of organized in terms of temperature increasing, right, solid, liquid, gas, plasma. 0:10:12.760 --> 0:10:15.920 And what happens there is the particles are disassociating as 0:10:15.960 --> 0:10:18.680 they get hotter and hotter, they tend to move around more, 0:10:18.720 --> 0:10:21.920 they have less restrictions. But there are these phase differences, right, 0:10:21.960 --> 0:10:26.960 Things don't go smoothly from solid to liquid and liquid 0:10:27.000 --> 0:10:30.520 to gas. They're these transitions where suddenly things behave different Wait, 0:10:30.600 --> 0:10:34.800 isn't there a middle state called the smoothie or a 0:10:35.080 --> 0:10:41.200 carbonated drink. That's right, it's called the margarita. That's the 0:10:41.240 --> 0:10:46.200 state of matter you discover after you win the Nogo process. Right, Yeah, 0:10:46.240 --> 0:10:49.480 it's made of dacorns. Now, So they're these interesting transitions, 0:10:49.480 --> 0:10:52.440 and that's fascinating, right that these particles tend to work 0:10:52.440 --> 0:10:54.400 in one way and then you cross them over a 0:10:54.400 --> 0:10:56.600 threshold and they tend to work in another way, Like 0:10:56.760 --> 0:10:59.600 there are different rules for gases and liquids and solids 0:10:59.640 --> 0:11:02.160 and lasmas, right. And it has something to do with 0:11:02.240 --> 0:11:07.360 the forces that bind atoms together and particles together, right, Like, 0:11:07.480 --> 0:11:11.079 at some point their energy is more than the that bond, 0:11:11.120 --> 0:11:14.520 and so they start arranging themselves in different ways exactly, 0:11:14.520 --> 0:11:16.880 And so you have to understand it from the microscopic 0:11:16.960 --> 0:11:19.480 You say, well, what's the dominant force? And just like 0:11:19.520 --> 0:11:22.440 you said, when things get cold with the dominant force, 0:11:22.600 --> 0:11:25.079 is this crystal structure of the atoms that are holding 0:11:25.120 --> 0:11:29.320 them together. And after that, the dominant energetic contribution is 0:11:29.360 --> 0:11:33.000 the kinetic energy of the objects. But there's still some bonds, right, 0:11:33.080 --> 0:11:35.800 the bonds between atoms and a liquid or what give 0:11:35.840 --> 0:11:38.640 you things like surface pressure and constant volume and stuff. 0:11:39.040 --> 0:11:41.240 And so you have to understand, like what are the 0:11:41.280 --> 0:11:43.920 dominant forces and how are they playing together? And so 0:11:44.000 --> 0:11:46.040 you take these little atoms and you try to think 0:11:46.360 --> 0:11:49.439 what are their emergent properties. And this is a really 0:11:49.520 --> 0:11:52.319 hard thing to do, to go from the microscopic like 0:11:52.440 --> 0:11:56.000 I have a few little particles to understanding the whole thing. 0:11:56.360 --> 0:11:59.319 It's like why hurricanes are difficult. You know, we understand 0:11:59.480 --> 0:12:02.720 how particles of water move through the atmosphere, it's not hard, 0:12:03.040 --> 0:12:05.920 But how do you understand ten trillion of them swirling 0:12:05.960 --> 0:12:09.520 around in really complex situations? So this kind of theory 0:12:09.640 --> 0:12:13.040 is very difficult. And Bows and Einstein we're playing around 0:12:13.080 --> 0:12:15.640 with the math and they figured out a new phase. 0:12:15.679 --> 0:12:18.240 They're like, oh, here's a way if you arrange the 0:12:18.280 --> 0:12:21.360 particles in this special way, you can get completely different 0:12:21.360 --> 0:12:25.080 behavior from anything we've seen. Well, I guess you're saying 0:12:25.080 --> 0:12:27.000 it's sort of like an emergent property that means that 0:12:27.480 --> 0:12:31.559 it's like how they all behave collectively, and you're saying 0:12:31.600 --> 0:12:33.800 that it doesn't you know, like you can't talk about 0:12:34.080 --> 0:12:36.920 one atom being solid, liquid or gas, right, you have 0:12:36.960 --> 0:12:39.160 to talk about like a collection of them, That's right. 0:12:39.160 --> 0:12:41.559 You have to talk about the state of like many particles, 0:12:41.880 --> 0:12:44.160 you know. I think about physics sort of like in layers. Right, 0:12:44.160 --> 0:12:47.319 we have rules for how the solar system operates, and 0:12:47.360 --> 0:12:49.840 we think about the planets as like an individual blob. 0:12:50.120 --> 0:12:52.959 But then we also have rules for how winds move 0:12:53.040 --> 0:12:55.880 and fluid dynamics, and then we have on another layer 0:12:55.920 --> 0:12:59.120 we have rules for individual particles, and then deeper down 0:12:59.160 --> 0:13:01.560 we have rules for like how the quarks move inside 0:13:01.559 --> 0:13:04.200 those particles. That in principle, all you need to know 0:13:04.360 --> 0:13:08.160 is the sort of lowest level stuff, the tiniest particles. 0:13:08.200 --> 0:13:12.960 Those really do determine everything else. But in practice it's hard. 0:13:13.040 --> 0:13:15.360 It's a hard way to do stuff, Like it's hard 0:13:15.360 --> 0:13:18.400 to predict how a hurricane works, even if you understand 0:13:18.520 --> 0:13:21.800 wind and water. And the amazing thing is how much 0:13:21.880 --> 0:13:26.160 interesting stuff you discover that's not fundamental like tiny particles, 0:13:26.160 --> 0:13:29.640 but comes out at the higher levels like hurricanes, And 0:13:29.720 --> 0:13:33.240 this stuff can be simply described by new laws of 0:13:33.280 --> 0:13:36.240 physics that work at that higher level, Like you don't 0:13:36.280 --> 0:13:39.480 need to know about particles to understand how cannonball flies, 0:13:39.520 --> 0:13:42.440 and have a math formula that describes it. And that's 0:13:42.480 --> 0:13:47.719 why phases of matter are super fascinating, not because they're fundamental, 0:13:47.920 --> 0:13:51.679 but because they emerge. All right, So then Einstein got 0:13:51.720 --> 0:13:55.240 together with this scientist called Bows and they hung out 0:13:55.280 --> 0:13:57.160 and worked out the math together. Or how did they 0:13:57.240 --> 0:13:59.640 work together? I think Bo's actually worked out the basic 0:13:59.720 --> 0:14:03.080 idea at first, and then Einstein reads paper and extended it, 0:14:03.440 --> 0:14:06.240 and the result was this prediction that if you took 0:14:06.280 --> 0:14:08.839 atoms and you made them not super hot like you 0:14:08.840 --> 0:14:11.880 would need to get a plasma, but super duper duper cold, 0:14:12.400 --> 0:14:15.480 then they would do something really interesting, but only if 0:14:15.520 --> 0:14:18.200 there were a certain kind of particle, a particle called 0:14:18.240 --> 0:14:21.120 a boson. Oh. I see, so this is not about atoms. 0:14:21.120 --> 0:14:25.200 It's more like when we're talking about particular particles. Well, 0:14:25.200 --> 0:14:27.840 there's two kinds of particles. There are fermions and there 0:14:27.840 --> 0:14:31.000 are bosons. Fermions are particles that have a certain kind 0:14:31.040 --> 0:14:33.560 of spin half an integer that can have spin one 0:14:33.600 --> 0:14:36.560 half or minus one half, and bosons are particles that 0:14:36.640 --> 0:14:38.640 have spin that are an integer. So they can have 0:14:38.680 --> 0:14:41.680 spin like one zero or minus one. Now that's not 0:14:41.720 --> 0:14:44.400 really a big deal, it doesn't really matter. But every atom, 0:14:44.440 --> 0:14:47.200 for example, is either a fermion or boson depending on 0:14:47.480 --> 0:14:49.840 how you build it up out of the little particles. 0:14:49.880 --> 0:14:53.440 So for example, rubidium is a boson because of the 0:14:53.480 --> 0:14:57.160 particles it's made out of. You can also have fermionic atoms. Oh, 0:14:57.440 --> 0:15:01.440 what are electrons? But are electron? Electrons are emions, and 0:15:01.600 --> 0:15:05.000 quarks are bosons. Right, Electrons are fermions and quarks are fermions. 0:15:05.400 --> 0:15:08.480 At the particle level, the smallest level, all of the 0:15:08.520 --> 0:15:14.800 matter particles quarks and leptons are fermions, while the force particles, photons, etcetera. 0:15:14.880 --> 0:15:19.560 Are bosons. But you can combine fermions together to make boson. 0:15:19.680 --> 0:15:23.920 So like two electrons together can make a bosonic pair 0:15:24.200 --> 0:15:26.360 because the one has can add up to an integer. 0:15:26.920 --> 0:15:29.920 And that's why, for example, you can make bosons out 0:15:29.920 --> 0:15:33.840 of fermions. Some really complicated spin arithmetic there that we 0:15:33.840 --> 0:15:36.000 probably don't want to get into. And vocabulary. I feel 0:15:36.000 --> 0:15:40.160 like you're confusing me with vocabulary again, Daniel. But like Higgs, 0:15:40.200 --> 0:15:42.400 boson then is made out of other things, or is 0:15:42.440 --> 0:15:44.920 the higgs boson and boson bosons don't have to be 0:15:45.040 --> 0:15:47.640 made the fermions. They can be fundamental like the higgs, 0:15:47.680 --> 0:15:50.560 but all the force particles like the higgs, boson, the photon, 0:15:50.640 --> 0:15:54.840 the w d z fundamentally are boson. But fermions can 0:15:54.880 --> 0:15:59.560 get together and become like boson. Yes, absolutely, you can 0:15:59.640 --> 0:16:03.640 combine find the half spin lego pieces to make integer 0:16:03.680 --> 0:16:06.360 spin pieces. I see, but they have to come in 0:16:06.440 --> 0:16:08.760 like in pairs. I guess right, Yeah, you have to 0:16:08.800 --> 0:16:10.440 combine them the right way. So does it have to 0:16:10.440 --> 0:16:12.480 do with like if the atom has an even number 0:16:12.520 --> 0:16:17.880 of electrons or yes, exactly, so you can make bosons, 0:16:18.000 --> 0:16:20.640 you can make fermions. Every atom can be fermions, you 0:16:20.680 --> 0:16:24.240 can have bosons, etcetera. But there's an important difference because 0:16:24.280 --> 0:16:28.200 bosons can do something that fermions cannot do, which is 0:16:28.280 --> 0:16:31.360 hang out together. You're saying, yes, they can hang out together. 0:16:31.400 --> 0:16:35.640 So fermions, for a reason that nobody really understands, can 0:16:35.720 --> 0:16:39.120 never share a quantum state. Like that's the reason why 0:16:39.280 --> 0:16:42.640 electrons which are fermions don't all lie in the ground 0:16:42.720 --> 0:16:44.720 state of an atom, like you have an atom with 0:16:44.760 --> 0:16:47.120 ten electrons in it. They don't all just lie in 0:16:47.160 --> 0:16:50.240 the lowest energy level. They stack on top of each other. 0:16:50.400 --> 0:16:52.560 The energy levels are a ladder. You can only have 0:16:52.680 --> 0:16:56.360 one electron per layer of the ladder because their fermions 0:16:56.360 --> 0:16:59.400 bosons are happy to all hang out at the bottom 0:16:59.480 --> 0:17:02.560 level in the nuts. In many configurations, like you can 0:17:02.600 --> 0:17:04.680 have a laser, which is a bunch of photons which 0:17:04.680 --> 0:17:07.840 are bosons, all in the same quantum states. And so 0:17:08.160 --> 0:17:12.240 we have two kinds of particles, bosons and fermions. And 0:17:12.480 --> 0:17:16.000 we understand sort of mathematically why this happens. It emerges 0:17:16.359 --> 0:17:18.840 from the math, but we don't really fundamentally and tutially 0:17:18.920 --> 0:17:21.800 understand why bosons can all hang out in the same 0:17:21.800 --> 0:17:25.280 state and formons just will not Like this, this famous 0:17:25.280 --> 0:17:28.000 story about how somebody asked Fineman he find me, can 0:17:28.040 --> 0:17:31.560 you explain this to us why bosons can all hang 0:17:31.560 --> 0:17:34.119 out in the same state and formons can't. And he 0:17:34.160 --> 0:17:35.960 came back and he said, you know, I don't have 0:17:36.000 --> 0:17:39.120 an explanation that I can use on like eighteen year olds, 0:17:39.160 --> 0:17:42.520 which means I don't really understand it. That's right. He's 0:17:43.040 --> 0:17:47.760 famous for saying nobody understands quantum physics, right, yeah, exactly, 0:17:48.200 --> 0:17:50.520 and you know it does come out of the mathematics, 0:17:50.520 --> 0:17:52.840 but we don't intuitively understand it. It's just a weird 0:17:52.920 --> 0:17:56.359 fact about the universe. But it means that if you 0:17:56.440 --> 0:18:00.119 put a bunch of Boson particles together, they can in 0:18:00.440 --> 0:18:04.879 all hang out in the coldest, lowest quantum state, and 0:18:04.960 --> 0:18:08.840 that is the Einstein bos concit. Yes, so they predicted 0:18:08.840 --> 0:18:10.920 that if you get a bunch of these particles together 0:18:11.119 --> 0:18:13.480 and you get them really cold, they can all be 0:18:13.520 --> 0:18:16.680 in the same quantum state. And then something really weird 0:18:16.720 --> 0:18:20.080 would happen that because they would be so close together 0:18:20.480 --> 0:18:25.640 and so cold that the size of their quantum wavelength 0:18:25.960 --> 0:18:28.600 would be larger than the distance between them, and so 0:18:28.640 --> 0:18:31.680 they would basically merge and all have the same quantum 0:18:31.720 --> 0:18:35.320 state and act like one big quantum particle. Alright, cool, 0:18:35.440 --> 0:18:37.640 let's get into it a little bit more and how 0:18:37.680 --> 0:18:40.600 that all works. But first let's take a quick break. 0:18:53.200 --> 0:18:56.320 All right, we're talking about the Bose Einstein condensate, and 0:18:56.359 --> 0:18:59.159 you're saying that it's related to this idea that bosons 0:18:59.280 --> 0:19:01.399 can hang out to other and they can share a 0:19:01.480 --> 0:19:04.760 quantum state. I guess maybe some people might be wondering 0:19:04.920 --> 0:19:07.280 what does that mean, Like they're sharing a quantum state. 0:19:07.320 --> 0:19:09.640 Does that mean that they have all the same quantum 0:19:09.680 --> 0:19:12.240 properties and are sitting in the same spot. It means 0:19:12.240 --> 0:19:13.800 that they sit on top of each other. They can 0:19:13.840 --> 0:19:16.040 be in the same location and they can share all 0:19:16.040 --> 0:19:19.280 the same quantum properties. And this is really interesting because 0:19:19.520 --> 0:19:22.639 usually you have just one particle in a quantum state, 0:19:23.000 --> 0:19:25.080 and you know, we know the quantum state is sort 0:19:25.080 --> 0:19:28.440 of a thing that controls what happens to one particle. 0:19:28.640 --> 0:19:30.520 It's like a list of all the possibilities for what 0:19:30.720 --> 0:19:33.280 that particle can do. But since you only ever have 0:19:33.400 --> 0:19:35.760 one particle in a quantum state, you don't really see 0:19:35.800 --> 0:19:39.000 the full distribution. But if you have a bunch of 0:19:39.040 --> 0:19:42.479 particles and they're all in that same one quantum state, 0:19:43.040 --> 0:19:45.199 then you can see sort of the whole distribution. You 0:19:45.200 --> 0:19:48.840 can like physically look at this thing and see, oh, 0:19:48.880 --> 0:19:51.960 here's the distribution of all the possible things that could 0:19:52.000 --> 0:19:54.919 happen to this particle. Because you have ten million particles 0:19:54.960 --> 0:19:57.239 and they're all in the same quantum states, you get 0:19:57.280 --> 0:19:59.879 to see sort of all the outcomes at once. A 0:20:00.119 --> 0:20:01.960 only if there are boson. Only if there are boson 0:20:02.040 --> 0:20:04.800 because only bosons can do this. Permons can only have 0:20:04.880 --> 0:20:08.040 one particle per quantum state. Bosons you can have any 0:20:08.160 --> 0:20:11.399 number of particles all in the lowest quantum state. Now, 0:20:11.560 --> 0:20:13.280 how do you get a bunch of particles in the 0:20:13.400 --> 0:20:16.239 same quantum state. Well, the only way really to do 0:20:16.280 --> 0:20:18.960 that is to push them up against the wall of temperature. 0:20:19.280 --> 0:20:20.800 But you can't get them all in the same quantum 0:20:20.840 --> 0:20:23.280 state if they're at two hundred degrees because there's a 0:20:23.280 --> 0:20:25.760 billion different quantum states. So what you do is you 0:20:25.840 --> 0:20:29.399 make them really really cold, so there's only one of 0:20:29.480 --> 0:20:32.280 state available to them, the lowest one, and then they 0:20:32.320 --> 0:20:35.159 all pile up in that quantum state. And Einstein and 0:20:35.200 --> 0:20:37.480 Bows predicted that if you did that, you would get 0:20:37.520 --> 0:20:41.480 this blob where the particles sort of lose their individuality. 0:20:41.560 --> 0:20:45.240 They become a macroscopically size like you could see it 0:20:45.720 --> 0:20:48.960 quantum mechanically behaving conject I guess maybe I'm getting tripped 0:20:49.000 --> 0:20:51.760 up because I'm thinking of these things as particles. It's 0:20:51.840 --> 0:20:54.400 like little things. But maybe you know, if you think 0:20:54.440 --> 0:20:57.000 of them as waves, then it maybe makes more sense. 0:20:57.080 --> 0:20:59.879 Like you know, fermions, you can't have a wave on 0:21:00.040 --> 0:21:02.800 top of another wave, but bosons they're happy to stack 0:21:02.880 --> 0:21:05.360 together as waves. It's that kind of what you're saying. Yeah, 0:21:05.400 --> 0:21:07.320 And every time you think about these things, you should 0:21:07.359 --> 0:21:10.520 not be thinking about a tiny, little spinning ball of matter, right, 0:21:10.560 --> 0:21:13.680 because that's not what they are. They're weird quantum mechanical objects. 0:21:14.000 --> 0:21:16.720 And the intuition you usually have about how a particle, 0:21:16.760 --> 0:21:20.239 a little thing moves through space doesn't work. But you're right, 0:21:20.280 --> 0:21:23.040 and you can apply that intuition to the waves because 0:21:23.040 --> 0:21:26.520 the waves follow all those rules, like waves are deterministic 0:21:26.560 --> 0:21:29.919 and their future can be predicted and actually move through space. 0:21:30.040 --> 0:21:32.960 So yes, you can imagine all those bosonic waves sort 0:21:32.960 --> 0:21:34.760 of stacking on top of each other. They're all doing 0:21:34.760 --> 0:21:37.760 the same thing, right, whereas like a fermion, a bunch 0:21:37.760 --> 0:21:40.400 of waves, they would all sort of avoid each other. Yeah, exactly, 0:21:40.440 --> 0:21:42.720 like droplets that repel each other. Yeah, or sort of 0:21:42.760 --> 0:21:45.000 like a game of connect for you know, you slide 0:21:45.040 --> 0:21:47.240 the pieces in and they stack on top of each other, 0:21:47.600 --> 0:21:49.320