WEBVTT 00:00:02.600 --> 00:00:06.360 This week, math is on trial, and today's charge 00:00:06.360 --> 00:00:09.439 is that mathematics fits the physical universe 00:00:09.439 --> 00:00:14.119 far better than we might expect. Ideas that begin 00:00:14.119 --> 00:00:18.179 in the human mind somehow, someway, describe 00:00:18.179 --> 00:00:22.160 things far beyond it. Why should that be true? 00:00:23.120 --> 00:00:26.420 Math often begins with someone exploring an idea 00:00:26.420 --> 00:00:30.160 simply because it's interesting. or not doing 00:00:30.160 --> 00:00:33.740 math to solve a practical problem. Yet again 00:00:33.740 --> 00:00:37.219 and again, these ideas turn out to describe the 00:00:37.219 --> 00:00:42.140 physical world with remarkable precision. We 00:00:42.140 --> 00:00:46.280 can use equations to describe how planets move, 00:00:46.600 --> 00:00:51.740 how light travels, how atoms behave, and how 00:00:51.740 --> 00:00:55.979 the universe expands. It reaches inside things 00:00:55.979 --> 00:00:59.850 too small for us to see, and across distances 00:00:59.850 --> 00:01:04.950 too large for us to imagine. Isn't that amazing? 00:01:05.670 --> 00:01:09.430 And the surprising part isn't simply that mathematics 00:01:09.430 --> 00:01:13.250 is useful. We expect a tool designed for a particular 00:01:13.250 --> 00:01:16.909 job to be useful. The surprising part is that 00:01:16.909 --> 00:01:19.810 mathematical ideas developed without a physical 00:01:19.810 --> 00:01:26.049 purpose often fit the universe anyway. In 1960, 00:01:26.469 --> 00:01:29.959 a famous physicist, Eugene Wigner called this 00:01:29.959 --> 00:01:32.980 the unreasonable effectiveness of mathematics 00:01:32.980 --> 00:01:37.439 in the natural sciences. He was not surprised 00:01:37.439 --> 00:01:41.719 that mathematics worked. What surprised him was 00:01:41.719 --> 00:01:45.540 just how well it worked. I mean, why should the 00:01:45.540 --> 00:01:48.640 universe have patterns that we can express mathematically? 00:01:49.299 --> 00:01:53.739 And why should the human mind be able to discover 00:01:53.739 --> 00:01:58.609 them? Math cannot answer these questions by itself, 00:01:58.829 --> 00:02:03.069 but the fit between mathematics and the universe 00:02:03.069 --> 00:02:09.090 is difficult to ignore. Well, when I think about 00:02:09.090 --> 00:02:12.250 my life, I can move through my day focused on 00:02:12.250 --> 00:02:15.250 the next problem that needs to be solved. And 00:02:15.250 --> 00:02:17.629 when I do that, it's easy to treat the universe 00:02:17.629 --> 00:02:20.530 as little more than just the background of my 00:02:20.530 --> 00:02:24.069 life. But when I stop and consider that the same 00:02:24.069 --> 00:02:27.310 mathematics that we explore in our minds can 00:02:27.310 --> 00:02:31.710 describe galaxies and atoms and light and space, 00:02:31.949 --> 00:02:36.469 it fills me with wonder. I do not know why we 00:02:36.469 --> 00:02:39.090 can understand the universe this way, but the 00:02:39.090 --> 00:02:42.650 fact that it can gives me a reason to pay attention. 00:02:43.990 --> 00:02:46.530 Mathematics reminds me that the world is not 00:02:46.530 --> 00:02:49.900 only something to study or to use. but it is 00:02:49.900 --> 00:02:53.300 also something to notice, appreciate, and enjoy. 00:02:54.939 --> 00:02:59.280 I find it deeply satisfying when math goes from 00:02:59.280 --> 00:03:05.080 explanation to wonder. So on the charge of fitting 00:03:05.080 --> 00:03:07.199 the universe with unreasonable effectiveness, 00:03:07.759 --> 00:03:13.120 mathematics is guilty. Well, maybe today is the 00:03:13.120 --> 00:03:16.580 day to pause from explaining something and simply 00:03:16.580 --> 00:03:19.379 notice something that fills you with wonder and 00:03:19.379 --> 00:03:19.699 joy.