WEBVTT - Did our Universe evolve? 0:00:00.160 --> 0:00:03.840 Hi, it's Jorge and Daniel here. And this holiday season, 0:00:03.920 --> 0:00:06.440 if you're looking for a gift for yourself, for a friend, 0:00:06.600 --> 0:00:09.000 or for your your family, why not get him the 0:00:09.039 --> 0:00:11.479 Gift of Answers about the Universe. To check out our 0:00:11.520 --> 0:00:14.640 new book Frequently Asked Questions about the Universe, you can 0:00:14.640 --> 0:00:18.160 find details at Universe f a Q dot com. Thanks 0:00:18.200 --> 0:00:30.800 for supporting the podcast. Happy holidays everyone, Hey or hey? 0:00:31.000 --> 0:00:34.479 Do you think that our universe is well suited to us? 0:00:35.479 --> 0:00:37.720 I don't know. I mean, some of it seems so 0:00:37.800 --> 0:00:42.040 staggeringly beautiful to our eyes, you know, like stars, the galaxies, 0:00:42.200 --> 0:00:45.520 even like the drama of the black holes. That's true, 0:00:45.560 --> 0:00:49.120 it's definitely something we can appreciate, but also sometimes seems 0:00:49.159 --> 0:00:51.960 like the universe is kind of alien to us. I 0:00:52.000 --> 0:00:54.160 think the universe is here first, so technically we are 0:00:54.200 --> 0:00:56.800 the eighteen Yeah, but you know, sometimes the way that 0:00:56.840 --> 0:00:59.360 it works is so bizarre and so strange that I 0:00:59.360 --> 0:01:02.040 wonder if we're ever going to understand it, if our 0:01:02.080 --> 0:01:05.360 minds are suited to it, maybe that's what makes it 0:01:05.520 --> 0:01:08.240 especially suited to us. What do you mean? You know, 0:01:08.280 --> 0:01:10.680 it's like the perfect puzzle to keep us entertained. For 0:01:10.840 --> 0:01:12.880 attorney it's like that toy you put in front of 0:01:12.880 --> 0:01:14.479 a toddler. Why you need to get some work done. 0:01:14.520 --> 0:01:17.720 It's like the TV for human toddlers. Maybe Steve Jobs 0:01:17.760 --> 0:01:35.440 created the universe. Hi, I'm poor Hammad, cartoonists and the 0:01:35.520 --> 0:01:39.520 creator of PhD comics. Hi I'm Daniel. I'm a particle physicist, 0:01:39.680 --> 0:01:43.720 and I'm constantly amazed at the strangeness and the bonkers 0:01:43.800 --> 0:01:46.400 nous of the universe that we live in. Do you 0:01:46.480 --> 0:01:49.200 think the universe is bonkers? Like it is bonkers or 0:01:49.320 --> 0:01:52.560 it was made bonkers or made by a bonkers I 0:01:52.600 --> 0:01:55.440 won't speak to the mind of the creator if one exists, 0:01:55.880 --> 0:01:59.040 but it does continue to astound me how strange and 0:01:59.080 --> 0:02:01.440 how weird the univer is, and the fact that it 0:02:01.600 --> 0:02:04.240 is weird, that it seems strange, that it's counter to 0:02:04.480 --> 0:02:07.200 our expectations because we are part of the universe, So 0:02:07.320 --> 0:02:09.720 why doesn't it feel intuitive to us? Well, you know 0:02:09.760 --> 0:02:12.800 what I always say, if your expectations are not being met, 0:02:12.840 --> 0:02:15.200 maybe you should change your expectations, Daniel, I should try 0:02:15.240 --> 0:02:18.280 the Scandinavian approach. Just expect to be disappointed all the 0:02:18.400 --> 0:02:21.519 time and then be pleased when you're not, or expect 0:02:21.560 --> 0:02:23.840 to be surprised. You know, it's only weird because you 0:02:23.919 --> 0:02:28.239 think it's weird because it doesn't mean but really, really, 0:02:28.320 --> 0:02:30.880 the universe was here first, so that's true. Maybe the 0:02:30.919 --> 0:02:33.960 universe thinks we're weird. We are kind of bonkers after all. 0:02:34.320 --> 0:02:37.600 Welcome to our bonkers podcast. Daniel and Jorge Explain the Universe, 0:02:37.639 --> 0:02:40.000 a production of I Heart Radio in which we have 0:02:40.240 --> 0:02:42.880 no idea what the universe thinks of us, but we 0:02:43.000 --> 0:02:46.600 do dive deep into what human minds think about the universe, 0:02:46.720 --> 0:02:49.000 the questions we have about the way it works. At 0:02:49.040 --> 0:02:52.919 the tiniest scale of frothing buzzing quantum particles to the 0:02:53.080 --> 0:02:56.760 very biggest scale of galaxy formations and the entire fate 0:02:56.880 --> 0:02:59.840 of the universe. We question the very nature of reality, 0:03:00.160 --> 0:03:02.600 peel it back to see what's going on underneath, and 0:03:02.680 --> 0:03:05.200 we explain all of it to you, at least as 0:03:05.280 --> 0:03:08.120 far as we understand. Yeah, because it is a pretty 0:03:08.200 --> 0:03:10.800 big universe, and there's a lot that seems very puzzling 0:03:10.880 --> 0:03:14.080 and perplexing to us. It's, you know, wonderful and amazing 0:03:14.320 --> 0:03:16.960 and beautiful it seems sometimes but also a little bit 0:03:17.200 --> 0:03:21.320 terrifying and powerful and sometimes even dangerous. It sometimes seems 0:03:21.360 --> 0:03:23.720 amazing that we even live here. You know, we could 0:03:23.720 --> 0:03:26.519 have been wiped out by a supernova nearby, or could 0:03:26.600 --> 0:03:28.960 be that with small changes in the nature of the particles, 0:03:29.040 --> 0:03:31.320 we couldn't have had the chemistry we need for life 0:03:31.360 --> 0:03:33.760 to happen. Sometimes it seems like a lot of things 0:03:33.840 --> 0:03:36.760 had to go just right for us to evolve and 0:03:36.960 --> 0:03:39.560 to survive. Yeah, and if we hadn't been here, who 0:03:39.600 --> 0:03:42.040 would be asking these questions? Daniel, That's the main question. 0:03:42.160 --> 0:03:48.720 Probably some better looking, smarter version of us. If that's yeah, impossible, 0:03:49.800 --> 0:03:52.520 but we just disproved that theory or improbable at least. 0:03:53.440 --> 0:03:55.680 But yeah, it is a pretty amazing universe. And sometimes 0:03:55.720 --> 0:03:57.280 you have to wonder, like, how did it come to 0:03:57.400 --> 0:03:59.680 be like that? And how coming it came to be? 0:04:00.000 --> 0:04:02.360 And we are here and we are looking at it 0:04:02.480 --> 0:04:04.400 and wondering how it works. That's right, and that is 0:04:04.440 --> 0:04:07.000 one of the deepest questions in physics. We are often 0:04:07.120 --> 0:04:10.400 asking how do things work? What's going on with these particles? 0:04:10.480 --> 0:04:13.200 But underlying that there is a question standing in the 0:04:13.280 --> 0:04:16.200 wings waiting for an answer, and that question really is 0:04:16.680 --> 0:04:19.760 why this universe? Why is the universe of this one 0:04:19.839 --> 0:04:22.000 and not some other one? Could it have been a 0:04:22.120 --> 0:04:24.920 different universe, or is this the only possible way for 0:04:25.240 --> 0:04:28.080 universe to exist? What does it mean that we ended 0:04:28.160 --> 0:04:30.840 up in this universe? Well, for thankful that we are 0:04:30.880 --> 0:04:32.920 in this universe, I guess, or that this universe is 0:04:33.000 --> 0:04:35.960 here for us. But to understand these questions sometimes you 0:04:36.040 --> 0:04:38.000 kind of have to look outside of physics to think 0:04:38.040 --> 0:04:40.680 about the new ways in which you might answer these 0:04:40.720 --> 0:04:43.400 types of queries. That's right, And when we look to biology, 0:04:43.480 --> 0:04:46.680 for example, we find a very compelling and very powerful, 0:04:46.960 --> 0:04:51.040 very broadly useful argument for understanding why creatures exist and 0:04:51.160 --> 0:04:53.800 have certain traits. When we look at, for example, the 0:04:53.920 --> 0:04:55.840 beaks of birds and ask like, why do they have 0:04:55.960 --> 0:04:57.880 that shape? We get the answer when we look at 0:04:57.920 --> 0:05:00.400 the nuts they eat or they bug that they have 0:05:00.520 --> 0:05:03.239 to pick up. They seem to be very well suited 0:05:03.320 --> 0:05:06.400 to their environment and for a reason. Yeah, So to 0:05:06.480 --> 0:05:13.720 be on the podcast really asking the question is the 0:05:13.880 --> 0:05:18.919 universe the result of natural selection? All right? We're asking 0:05:19.000 --> 0:05:21.120 some big questions. Did they hear? I know that's sort 0:05:21.160 --> 0:05:23.640 of mind blowing to imagine, Like the universe is a 0:05:23.720 --> 0:05:27.760 bird on an island somewhere picking on bugs. I thought 0:05:27.800 --> 0:05:30.240 we were the birds, aren't we the birds. I think 0:05:30.279 --> 0:05:33.480 we might be the bugs and or the nuts, like 0:05:33.560 --> 0:05:36.440 the nuts are we're wondering how some some things are 0:05:36.480 --> 0:05:38.920 are suited to eat us. No, we are the birds, 0:05:39.000 --> 0:05:40.880 and when physics is the nuts and we're trying to 0:05:40.960 --> 0:05:43.400 crack it open. Oh boy, I'm getting lost in these 0:05:43.440 --> 0:05:46.000 analogies here. I know I'm driving you nuts, But it 0:05:46.240 --> 0:05:48.680 is a fun idea to wonder if the universe could 0:05:48.720 --> 0:05:51.120 have been other ways, and if the universe that we 0:05:51.240 --> 0:05:53.880 ended up when is this way because of some sort 0:05:53.920 --> 0:05:58.280 of process that guides the formation of universes to end 0:05:58.360 --> 0:06:01.720 up at one that sort of works. WHOA you mean 0:06:01.800 --> 0:06:08.960 like the evolution of universe is multiple universes over countless time, 0:06:09.320 --> 0:06:12.000 somehow changing and evolving. Yeah, that's the idea. We have 0:06:12.080 --> 0:06:15.360 talked about multiverses and many times on this podcast. But 0:06:15.480 --> 0:06:17.280 this is sort of like a different take. Instead of 0:06:17.360 --> 0:06:20.640 imagining the universe is actually many universes all sort of 0:06:20.760 --> 0:06:23.920 rolled up into one grand idea, this is like maybe 0:06:23.960 --> 0:06:26.880 our universe is in competition with other universes on some 0:06:26.960 --> 0:06:30.960 sort of like meta universe playing field. WHOA like an 0:06:31.040 --> 0:06:34.320 African savannah but for universes. And then there's some kind 0:06:34.360 --> 0:06:38.000 of predator, some universe predator, some universe eating. I think 0:06:38.040 --> 0:06:39.800 I saw that on an episode of the new show 0:06:39.920 --> 0:06:43.640 Look what can eat an entire universe? Exactly right, and 0:06:43.720 --> 0:06:46.400 so maybe Marvel got it right. As usual, they can 0:06:46.440 --> 0:06:49.240 do no wrong. Well, this is a kind of a 0:06:49.400 --> 0:06:52.320 mind bogging question, big ideas here, and so we were 0:06:52.360 --> 0:06:54.880 wondering how many people out there had thought about the 0:06:55.200 --> 0:06:58.400 universe as evolving and or as being the result of 0:06:58.600 --> 0:07:01.600 something like natural select. So Daniel went out there as 0:07:01.680 --> 0:07:04.080 usual and ask people on the internet what they thought 0:07:04.120 --> 0:07:06.000 of this question. That's right, and so thank you to 0:07:06.040 --> 0:07:09.600 everybody who's willing to entertain my crazy questions without the 0:07:09.640 --> 0:07:12.920 opportunity to think about it or to prepare. If you'd 0:07:13.000 --> 0:07:15.200 like to participate for a future episode, we would love 0:07:15.280 --> 0:07:17.840 to hear your voice on the podcast. Just to write 0:07:17.920 --> 0:07:20.800 us an email, no special equipment required. Shoot us an 0:07:20.840 --> 0:07:24.160 email two questions at Daniel and Jorge dot com. So 0:07:24.320 --> 0:07:26.040 think about it for a second. If someone asked you 0:07:26.560 --> 0:07:31.360 what is cosmological natural selection? What would come to mind 0:07:31.680 --> 0:07:34.640 in your brain? Here's what people had to say. I'm 0:07:34.640 --> 0:07:41.320 gonna say those bodies orbiting around a star that have 0:07:41.720 --> 0:07:48.040 the most stable gravitational orbits last the longest. Every star 0:07:48.160 --> 0:07:51.240 for itself, may the strongest in the universe survive and 0:07:51.360 --> 0:07:55.400 the weakest universal objects becomes space test well, I guess 0:07:55.680 --> 0:07:59.840 planet stars, gallessies, etcetera. Survival of the fittest would apply 0:08:00.120 --> 0:08:06.920 to another star is more likely to pass on positive traits. 0:08:07.720 --> 0:08:10.360 Does that have an influence on the next generation stars. 0:08:10.760 --> 0:08:13.040 Maybe it's a theory that explains why there are no 0:08:13.200 --> 0:08:16.400 medium sized black holes by using an analogy from evolution. 0:08:17.080 --> 0:08:19.760 Maybe there were some conditions in the environment that made 0:08:19.800 --> 0:08:22.960 them go extinct, while the supermassive black holes with you 0:08:23.040 --> 0:08:26.160 today lived on and appropriated. Assuming that's the thing they 0:08:26.200 --> 0:08:28.720 can do, all right. Nobody said in African Savannah with 0:08:28.760 --> 0:08:34.040 the universes, nobody talked about something eating universes. It's a 0:08:34.120 --> 0:08:38.199 pretty crazy idea to encapsulate in just three words, cosmological 0:08:38.320 --> 0:08:40.400 natural selection. So we didn't give them a whole lot 0:08:40.480 --> 0:08:42.920 to go on. It seems like people didn't trigger something 0:08:43.000 --> 0:08:45.200 big in their heads. Like most people stuck to stars 0:08:45.280 --> 0:08:48.839 or galaxies as maybe evolving, but nobody thought about the 0:08:48.960 --> 0:08:52.200 universe evolving. It's sort of too crazy, you know, it's 0:08:52.200 --> 0:08:54.599 sort of too big an idea to even leap to 0:08:55.200 --> 0:08:57.199 from this concept. It's sort of bold. But you know, 0:08:57.280 --> 0:08:59.400 I like that. I like that about bold ideas. Like 0:08:59.840 --> 0:09:02.360 for as you hear about someing, you think, what, that's great. 0:09:02.520 --> 0:09:04.600 Hold on a second, maybe that makes a little bit 0:09:04.640 --> 0:09:07.600 of sense. That's the nice thing about crazy, big ideas. 0:09:07.880 --> 0:09:10.120 I guess. You know, even ideas like the multiverse, at 0:09:10.160 --> 0:09:13.599 some point, you know, seem crazy and insane, and but 0:09:13.720 --> 0:09:16.160 now people seem to kind of accept it, and some 0:09:16.240 --> 0:09:19.880 people even assume it's true, like people like Marvel. That 0:09:20.000 --> 0:09:23.600 you can't necessarily turn that around. Just because some ideas 0:09:23.640 --> 0:09:26.120 which now make a lot of sense once seemed crazy 0:09:26.480 --> 0:09:29.880 doesn't mean that every crazy seeming idea will eventually make sense, 0:09:30.040 --> 0:09:33.320 right right, right. Sense only works one way, It only 0:09:33.360 --> 0:09:35.559 makes sense, it makes sense one way. There are a 0:09:35.559 --> 0:09:37.640 lot of crazy seeming ideas that we don't talk about 0:09:37.640 --> 0:09:40.840 it anymore because they still seem crazy right the whole, 0:09:40.920 --> 0:09:44.400 Like the universe is like turtles and turtles all the 0:09:44.440 --> 0:09:48.280 way down on top of some elephants or something that 0:09:48.360 --> 0:09:52.040 also seemed bonkers. But that doesn't mean it's true. Yeah, exactly, 0:09:52.120 --> 0:09:54.760 it's gotta have some legs, it's got to solve some problems, 0:09:54.800 --> 0:09:57.160 it's got to open up avenues for exploration, and it's 0:09:57.160 --> 0:09:59.760 got to sort of hang together mathematically. Well, I mean, 0:10:00.120 --> 0:10:02.920 turtles do solve all problems you think about it, and 0:10:03.160 --> 0:10:05.600 they have legs and they do have legs. Yeah, although 0:10:05.600 --> 0:10:07.600 they do it kind of slowly, so I mean we're 0:10:07.640 --> 0:10:09.760 still waiting for those turtles. All right, Well, to step 0:10:09.880 --> 0:10:11.920 us through this, Daniel, this big idea, what is the 0:10:12.000 --> 0:10:16.720 cosmological natural selection? So cosmological natural selection is a really 0:10:16.800 --> 0:10:20.800 fun creative idea by a physicist named Lee Smollen, a 0:10:21.000 --> 0:10:25.680 theoretical physicist, and it's in solution to what physics calls 0:10:25.800 --> 0:10:28.640 a fine tuning problem, which is just a fancy way 0:10:28.640 --> 0:10:31.400 of saying, like, why is the universe the way that 0:10:31.480 --> 0:10:33.920 it is, because it seems like it could have been 0:10:34.040 --> 0:10:37.400 lots of other ways. So before we dig into how 0:10:37.520 --> 0:10:40.120 he tries to answer that question, let's make sure we 0:10:40.240 --> 0:10:42.360 have like a good grasp on what the question is. 0:10:42.480 --> 0:10:44.520 What is the problem we're trying to solve. Why is 0:10:44.559 --> 0:10:46.800 the tricky to understand that the universe is this way 0:10:46.840 --> 0:10:49.720 and not some other way? Right? Because you know, as physicist, 0:10:49.760 --> 0:10:52.000 you've been sort of drilling down on the equations that 0:10:52.200 --> 0:10:54.760 make the universe work, and at some point you come 0:10:54.960 --> 0:10:57.120 upon something that you're like, you can't explain, like it 0:10:57.280 --> 0:10:59.480 just seems to be the way it is, because it 0:10:59.559 --> 0:11:01.640 seems to be the way it is, Like you can't 0:11:01.640 --> 0:11:04.599 really explain why pious three point one four or the 0:11:04.760 --> 0:11:08.719 cosmological constant is is X. Right, that's exactly right. You know. 0:11:08.800 --> 0:11:12.400 The grand goal of physics is to summarize everything we see, 0:11:12.440 --> 0:11:16.000 all phenomena, all matter, all energy, all forces in terms 0:11:16.120 --> 0:11:19.520 of one concept, you know, like maybe a single equation 0:11:19.640 --> 0:11:21.559 that we could write onto a T shirt. And so 0:11:21.679 --> 0:11:23.599 we've made a lot of progress there. We have a 0:11:23.679 --> 0:11:26.200 few equations. They don't quite fit onto a T shirt, 0:11:26.280 --> 0:11:28.480 but they're kind of beautiful and compact, and you know, 0:11:28.559 --> 0:11:31.160 they describe a portion of the universe that we understand 0:11:31.240 --> 0:11:33.360 that we've explored. Well, it depends on the size of 0:11:33.440 --> 0:11:36.120 your your T shirt. Just get a bigger T shirt, 0:11:36.120 --> 0:11:38.319 Like I said, just adjust your expectations of what a 0:11:38.440 --> 0:11:41.920 T shirt uh is or how many people can fit in. 0:11:42.000 --> 0:11:44.719 It might solve your problem. That's right. If we go 0:11:44.800 --> 0:11:46.880 to micro font and then it's no problem. We can 0:11:46.920 --> 0:11:49.679 describe the whole universe on a T shirt. But currently 0:11:49.679 --> 0:11:52.079 we have this model of particles and their interactions. We 0:11:52.160 --> 0:11:54.320 call it the standard model, and as you say, there 0:11:54.320 --> 0:11:56.719 are parts of it that we don't understand, you know, 0:11:56.800 --> 0:11:58.840 not just the structure, but there's lots of questions about 0:11:58.880 --> 0:12:01.280 the structure of you know, like why are their copies 0:12:01.320 --> 0:12:04.520 of these particles electron, Muan, Tau, but also just we 0:12:04.640 --> 0:12:08.199 find numbers in these equations, and those numbers have no 0:12:08.440 --> 0:12:11.480 explanation that we can find. They are just numbers, and 0:12:11.520 --> 0:12:13.640 the theory doesn't tell us what those numbers have to be. 0:12:13.800 --> 0:12:15.880 We have to go out and measure them. One of 0:12:15.960 --> 0:12:18.800 these numbers, for example, as you say, is the cosmological constant, 0:12:19.040 --> 0:12:21.800 this rate at which the universe seems to be expanding. 0:12:22.200 --> 0:12:24.280 We don't know why that number is what it is. 0:12:24.360 --> 0:12:26.800 We have no theoretical prediction for what it should be. 0:12:27.080 --> 0:12:29.880 It's just like a placeholder, like a parameter. It's sort 0:12:29.920 --> 0:12:32.640 of like you're in the control panel for the universe 0:12:32.720 --> 0:12:35.160 and it just has these knobs. You know. The structure 0:12:35.200 --> 0:12:37.320 of the universe is this control panel, and you could 0:12:37.400 --> 0:12:40.040 turn the values of these parameters up or down and 0:12:40.120 --> 0:12:43.520 maybe get different universes that follow the same basic laws 0:12:43.559 --> 0:12:46.880 of physics. But you know, with different settings on those knobs, right, 0:12:46.920 --> 0:12:49.439 they seem like arbitrary, like somebody came in before you 0:12:49.640 --> 0:12:51.959 and adjusted to those dials, and then you came in 0:12:52.040 --> 0:12:54.680 and you're like, why did you set these dials? Yes, exactly, 0:12:54.760 --> 0:12:56.880 we have no explanation and for why these numbers are 0:12:56.960 --> 0:12:58.760 where they are. And you might be tempted to think 0:12:58.760 --> 0:13:01.400 about numbers like this speed of light because we don't 0:13:01.440 --> 0:13:03.720 know why the speed of light is the speed of light, 0:13:03.840 --> 0:13:06.280 you know, why isn't it not faster or slower. It's 0:13:06.320 --> 0:13:09.080 a little tricky because the speed of light has units 0:13:09.160 --> 0:13:11.960 on it, right, it's meters per second. So the actual 0:13:12.160 --> 0:13:14.800 number there depends on the units you choose. If you 0:13:15.160 --> 0:13:17.040 change the meter or change the second, you get a 0:13:17.080 --> 0:13:20.800 different number. So physicists like to focus on dimensionless numbers. 0:13:20.840 --> 0:13:23.959 You can rearrange all these constants of the universe in 0:13:24.160 --> 0:13:26.160 ratios and whatever to get rid of the units in 0:13:26.320 --> 0:13:29.800 unit with pure numbers numbers that just are. And you know, 0:13:29.920 --> 0:13:32.679 if all those numbers were one, we'd be like, cool, 0:13:33.000 --> 0:13:35.040 that makes sense. Where if all those numbers were ten 0:13:35.200 --> 0:13:37.440 or something, it would make sense. But they're all really different. 0:13:37.480 --> 0:13:39.000 Some of them are really small, some of them are 0:13:39.080 --> 0:13:41.640 really large, and we just have no explanation for them. So, 0:13:41.760 --> 0:13:44.600 as you say, they seem kind of arbitrary, and we wonder, 0:13:44.720 --> 0:13:47.319 you know, like could they be different? Could you have 0:13:47.440 --> 0:13:50.120 had another universe with different values of those numbers? And 0:13:50.160 --> 0:13:51.920 we think through like what the physics could be like. 0:13:52.320 --> 0:13:54.280 But the physics would be really really different in the 0:13:54.360 --> 0:13:56.760 universe would be totally different from the one we see. 0:13:57.320 --> 0:14:00.079 And so we wonder, like, why are these values what 0:14:00.280 --> 0:14:02.240 they are? They seem to be sort of just right 0:14:02.440 --> 0:14:05.000 to give us the universe that we have. So these 0:14:05.040 --> 0:14:08.320 are like ratios, I imagine it would be like saying, 0:14:08.320 --> 0:14:10.679 what is the rate at which the universe is expanding? 0:14:10.760 --> 0:14:14.000 It's like, you know, there's seven point four seven percent 0:14:14.280 --> 0:14:17.040 and so that's that's a dimensionless constant to write a percentage. 0:14:17.160 --> 0:14:18.800 So is that what you mean? Like ratios of like 0:14:18.920 --> 0:14:21.680 the number of so and so particles through so and 0:14:21.760 --> 0:14:24.360 so other particles. Yeah, that kind of thing. So one 0:14:24.400 --> 0:14:26.840 of the most important dimensionless constant is called the fine 0:14:26.880 --> 0:14:29.920 structure constant. It includes the speed of light and the 0:14:30.080 --> 0:14:33.440 charge of the electron and planks constant. And if you 0:14:33.520 --> 0:14:36.320 change that number, then physics changes because that affects like 0:14:36.600 --> 0:14:39.280 how strongly. Electrons and pausit trying to repel each other, 0:14:39.440 --> 0:14:42.320 and you know the distances at which things feel these 0:14:42.400 --> 0:14:45.360 kinds of forces. Other important ones are ratios of the 0:14:45.480 --> 0:14:48.240 masses of the particles, like why is the muan so 0:14:48.360 --> 0:14:51.200 much heavier than the electron? Why is the top corks 0:14:51.240 --> 0:14:54.120 so much heavier than everything else? You know, if you 0:14:54.240 --> 0:14:57.280 change those numbers, you also really change how physics work, 0:14:57.720 --> 0:14:59.920 you know, like what if the electron wasn't the light 0:15:00.080 --> 0:15:02.200 just leapt on? What if we had muans in our 0:15:02.480 --> 0:15:05.840 bodies instead of electrons because muans were lighter mass, Like 0:15:05.920 --> 0:15:08.360 that would really change everything, right, But you're you're really 0:15:08.400 --> 0:15:10.880 sort of asking two questions, right, aren't you. Like you're asking, 0:15:11.080 --> 0:15:13.080 for example, in the case of the electron, like what 0:15:13.240 --> 0:15:15.240 is the mass of the electron the way it is? 0:15:15.480 --> 0:15:19.120 And also why is the mass of the other cousins 0:15:19.200 --> 0:15:22.240 of the electron you know a certain number of times 0:15:22.280 --> 0:15:24.920 dead mass with the electron? Yeah, exactly. And so there's 0:15:24.960 --> 0:15:26.600 lots of different ways you're going to arrange these things. 0:15:26.640 --> 0:15:29.400 But fundamentally, we're looking at a set of numbers, and 0:15:29.520 --> 0:15:32.520 those numbers control the way the universe is, and we 0:15:32.640 --> 0:15:36.320 don't know why those numbers are what they are, and 0:15:36.640 --> 0:15:39.360 you know, as you said earlier, one possible explanation is, 0:15:39.680 --> 0:15:42.000 we know if those numbers were different, who would be 0:15:42.160 --> 0:15:46.040 here asking that question? And that's a popular answer, and 0:15:46.080 --> 0:15:48.440 it goes by the name of the anthropic principle. It 0:15:48.560 --> 0:15:50.960 just says that if the numbers were different, you wouldn't 0:15:50.960 --> 0:15:53.240 get humans and you wouldn't get intelligence, and nobody would 0:15:53.240 --> 0:15:56.240 be asking. So only in a universe where things happen 0:15:56.320 --> 0:15:58.160 to work in just this way do you have people 0:15:58.240 --> 0:16:00.120 to ask that question? So you want to ask that 0:16:00.280 --> 0:16:03.080 question when it's possible, And that's sort of like a 0:16:03.200 --> 0:16:05.560 circular explanation, but a lot of people like that answer. 0:16:05.800 --> 0:16:07.640 Sort of like my kids asking why is our house 0:16:07.720 --> 0:16:10.320 designed that way? It's like they are just born into 0:16:10.360 --> 0:16:12.720 the house. Been born in a different house, they would 0:16:12.720 --> 0:16:15.600 be asking a different question about that house. Yeah. Or 0:16:15.680 --> 0:16:18.200 it's like kids asking, you know, why am I here? 0:16:18.520 --> 0:16:21.560 Why was I created? And not some other kid? You know, like, well, 0:16:21.600 --> 0:16:23.400 if I had had a different kid, because you know, 0:16:23.480 --> 0:16:25.840 you've been conceived in a different moment, that kid might 0:16:25.880 --> 0:16:28.520 be asking the same question, or you know, have different 0:16:28.560 --> 0:16:31.320 interests or whatever, ask a different question. Right, Basically, you 0:16:31.320 --> 0:16:35.360 want to tell your kids they're not special. Of course, 0:16:35.520 --> 0:16:39.480 my kids are special. Everybody else kids I don't know about. Yeah, 0:16:39.480 --> 0:16:43.640 it sounds like anthropic parenting. And my complaint with this 0:16:44.200 --> 0:16:46.120 is that it's sort of like giving up. It's sort 0:16:46.160 --> 0:16:49.320 of like saying there is no explanation, look no further, 0:16:49.880 --> 0:16:52.560 Whereas what I like in science is when you're always 0:16:52.600 --> 0:16:55.040 trying to dig deeper. You're always saying, there must be 0:16:55.160 --> 0:16:57.640 a reason for this to happen. Let's look deeper, because 0:16:57.720 --> 0:17:00.680 it's possible that there is a deeper sir. Right, We 0:17:00.920 --> 0:17:03.680 certainly don't have the final theory of physics. We know 0:17:04.000 --> 0:17:07.280 that our description of particles and their interactions is flawed 0:17:07.320 --> 0:17:09.600 and limited, because we know, for example, it breaks down 0:17:09.720 --> 0:17:12.119 if you have really really high energies. Our theory just 0:17:12.320 --> 0:17:14.880 doesn't work. And so we know we need some sort 0:17:14.880 --> 0:17:17.320 of deeper theory. And so maybe you know there is 0:17:17.359 --> 0:17:19.760 some deeper explanation one we just haven't found yet, that 0:17:19.880 --> 0:17:22.639 explains these values and says these values have to be 0:17:22.880 --> 0:17:26.480 certain numbers, like, there's not arbitrary. It only works if 0:17:26.520 --> 0:17:28.720 they are these numbers. We just don't quite see the 0:17:28.760 --> 0:17:31.560 full picture yet, And so I don't like the entropic answer, 0:17:31.600 --> 0:17:34.399 because I always want to strive for that deeper understanding, right, 0:17:34.440 --> 0:17:37.360 Like maybe you'll dig deeper into the equations and find 0:17:37.440 --> 0:17:39.200 that if the electron had half the mass that it 0:17:39.280 --> 0:17:42.080 does right now, it just doesn't make for a logical 0:17:42.240 --> 0:17:45.000 universe or like a universe dead. You know, it gives 0:17:45.040 --> 0:17:47.479 you tupiles to equal seven, Like that's what you want. 0:17:47.520 --> 0:17:49.720 You wanted to boil it down to one question and say, look, 0:17:49.760 --> 0:17:53.119 if you change this, then you wouldn't it wouldn't logically work, right, 0:17:53.119 --> 0:17:55.240 because that's kind of the only alternative when you say, 0:17:55.320 --> 0:17:57.200 like it's think things have to be a certain way, 0:17:57.640 --> 0:17:59.959 like not being able to be a certain way mean 0:18:00.200 --> 0:18:03.280 that it would be illogical. Yeah, And people are looking 0:18:03.400 --> 0:18:06.159 for a theory of the universe that's self consistent, right, 0:18:06.240 --> 0:18:09.480 So the sort of philosophical implication there is that only 0:18:09.600 --> 0:18:13.879 self consistent universes can exist. And so maybe there's a 0:18:13.960 --> 0:18:16.800 reason why those other values of those numbers make for 0:18:16.880 --> 0:18:20.080 some inconsistency, and there you need to have some sort 0:18:20.119 --> 0:18:23.480 of physics principle we haven't yet discovered, right that shows 0:18:23.560 --> 0:18:26.200 us why those things would be inconsistent, you know, And 0:18:26.440 --> 0:18:28.200 we don't have that, but we can sketch the sort 0:18:28.240 --> 0:18:31.359 of like rough idea. You know, maybe for example, string 0:18:31.520 --> 0:18:34.480 theory is correct, and at the basic level the universe 0:18:34.560 --> 0:18:37.800 are these little, tiny vibrating strings and they can only 0:18:37.880 --> 0:18:41.320 vibrate in certain ways and because of their basic fundamental nature, 0:18:41.440 --> 0:18:44.080 and that leads to certain properties that we then measure, 0:18:44.240 --> 0:18:46.240 you know, at our scale, which have to come out 0:18:46.280 --> 0:18:48.399 this certain way, and that you just can't have an 0:18:48.440 --> 0:18:50.840 electron with a different charge, and you can't have them 0:18:50.880 --> 0:18:53.480 you want with four times as much mass as the electron. 0:18:53.760 --> 0:18:55.479 You have to have the numbers that we have now, 0:18:56.000 --> 0:18:58.240 and it comes out of some deeper logic that we 0:18:58.359 --> 0:19:00.479 just don't know yet. So we don't have that theory yet, 0:19:00.520 --> 0:19:03.600 but you know, you can imagine that kind of theory existing, right. 0:19:03.640 --> 0:19:05.880 But that is still satisfy you though as a physicist, 0:19:06.000 --> 0:19:07.639 like did you say, Well, that's just the way the 0:19:07.760 --> 0:19:10.119 universe is, and it has to be that way because 0:19:10.160 --> 0:19:12.639 of the way the universe is. I'll never be satisfied, 0:19:12.920 --> 0:19:15.639 absolutely not when we get that answer that explains all 0:19:15.640 --> 0:19:17.879 the mysteries we see today. There will just always be 0:19:17.960 --> 0:19:19.920 more questions. And that's what I don't like about the 0:19:19.960 --> 0:19:22.640 anthropic principle because it stops you from asking that next 0:19:22.760 --> 0:19:24.920 round of questions, whereas I feel like science is this 0:19:25.000 --> 0:19:27.760 cycle of digging every deeper into the most basic questions. 0:19:27.800 --> 0:19:29.960 And you know, even if we exhaust physics and we 0:19:30.119 --> 0:19:33.080 get just one single theory that describes the whole universe, 0:19:33.160 --> 0:19:35.840 will always have philosophy because we can always ask like, well, 0:19:35.920 --> 0:19:39.480 what does it mean? Man? What does it mean? And 0:19:39.680 --> 0:19:43.080 that's one potential way to answer why the universe is 0:19:43.119 --> 0:19:44.800 the way it is, Why those numbers are all the 0:19:44.880 --> 0:19:47.440 way that the numbers that they are. Maybe there's some 0:19:47.600 --> 0:19:50.280 asked yet to be discovered, you know, equation or theory 0:19:50.359 --> 0:19:52.280 that explains them all that makes them want to be 0:19:52.400 --> 0:19:55.119 those numbers or makes them have to be those numbers. 0:19:55.640 --> 0:19:58.640