1 00:00:18,040 --> 00:00:25,940 Well, the 30th of May 1832, a gunshot was heard ringing out across the building this morning. 2 00:00:25,960 --> 00:00:30,640 Paris, a peasant who was walking to the market that morning, ran towards the end. 3 00:00:30,640 --> 00:00:38,170 Gunshot was over and on the ground, he found a young man writhing in pain, clearly shot by a shooting. 4 00:00:39,250 --> 00:00:46,600 The young man was taken to a local hospital in a country hospital where he to stay in the arms of his brother, Alfred. 5 00:00:46,690 --> 00:00:50,110 The lawsuits, he says, were too high. Me, Alfred. 6 00:00:50,200 --> 00:00:54,850 I need all the courage I can muster to die at the age of 20. 7 00:00:55,840 --> 00:01:02,950 The young man's name was every Galois. He was a well-known revolutionary in Paris at the time. 8 00:01:04,810 --> 00:01:08,740 Actually, this is if you want to see me any private at all. 9 00:01:10,700 --> 00:01:19,720 Yes. Yes. Now, this is that is actually happening when I was about ten years before the IDF came out and. 10 00:01:22,300 --> 00:01:26,300 The young man. The young man's name was every schoolboy. 11 00:01:26,560 --> 00:01:29,620 He was a well-known revolutionary in Paris at the time. 12 00:01:30,130 --> 00:01:34,600 Now, it's not quite clear what the jewel that morning was about. 13 00:01:35,440 --> 00:01:39,650 Some say that it was, in fact, a duel with a friend of his over a woman. 14 00:01:39,730 --> 00:01:48,070 They both had fallen in love with others. And actually it was the establishment trying to get rid of this troublesome revolutionary. 15 00:01:48,730 --> 00:01:55,510 There's even a conjecture that he staged his own dance in order to try and spark a new revolution in Paris. 16 00:01:56,080 --> 00:02:04,180 Well, now it's unclear what that duel was about, but it wasn't revolutionary politics for which this young man became famous, 17 00:02:04,180 --> 00:02:13,600 because a few years earlier, while still at school, every school law had solved one of the big mathematical problems at the time. 18 00:02:14,410 --> 00:02:18,700 Now, he went to the parents academy trying to explain his great breakthrough. 19 00:02:18,940 --> 00:02:27,130 But the academicians in Paris couldn't understand a word of what he was talking about, partly because this is how he wrote most of his mathematics. 20 00:02:28,980 --> 00:02:29,300 Anyway, 21 00:02:29,530 --> 00:02:38,320 the night before that duel he realised that probably this was going to be his last chance to try and explain the great breakthrough that he made. 22 00:02:38,350 --> 00:02:47,110 So he actually set off the whole night before the duel, writing the line to a friend, trying to articulate this great breakthrough he made. 23 00:02:48,460 --> 00:02:52,840 And as a dawn arose and the new day, he went out to meet his destiny. 24 00:02:53,470 --> 00:02:57,750 Probably in fact been doing maths all night with the fact that he was such a bad shot that morning. 25 00:02:57,760 --> 00:03:03,030 But. But as you say, there's documents that he left behind on his desk. 26 00:03:03,040 --> 00:03:10,989 Many of us regard as some of the most important mathematical documents in the whole history of my subjects, because hidden in so many, 27 00:03:10,990 --> 00:03:23,140 that was a new language, a language to help us to explain one of the biggest ideas in mathematics and in science, namely the idea of symmetry. 28 00:03:23,500 --> 00:03:26,620 This language that he developed was called group theory. 29 00:03:26,920 --> 00:03:35,140 Now, I, as a mathematician, use this language that got a lot of evidence already, just by the age of 20, 30 00:03:35,320 --> 00:03:41,770 every day in my working life, in order to be able to understand and navigate the world of symmetry. 31 00:03:42,130 --> 00:03:48,460 It's interesting. Although I became a mathematician on my Galois, I think our Morning Edition went on. 32 00:03:48,700 --> 00:03:52,210 When I was younger, I hadn't wanted to be a mathematician at all. 33 00:03:52,240 --> 00:03:55,600 In fact, my dream when I was a school was in fact to become a spy. 34 00:03:57,100 --> 00:04:04,660 This is partly fuelled by my mother, who works for the Foreign Office, and when she had children, she had to retire. 35 00:04:05,230 --> 00:04:10,510 That's a she told me and my sister that she'd been allowed to keep the black gun of 36 00:04:10,510 --> 00:04:15,640 every member of the Foreign Office and that it was hidden somewhere inside our house. 37 00:04:16,180 --> 00:04:22,030 So my sister and I used to spend all our face and try to find where this black gun was. 38 00:04:22,270 --> 00:04:27,010 Never find it. They obviously told her the answer concealed very well as well, but some. 39 00:04:27,220 --> 00:04:31,180 So I decided that I was going to join the Foreign Office like my mother. 40 00:04:31,180 --> 00:04:39,970 And then I thought having becoming a spy. So when I got to secondary school, I went to a safe school here in Oxfordshire. 41 00:04:41,020 --> 00:04:50,110 I signed on for every language that my my school, the Foreign Office, found any languages, the French, Latin, German. 42 00:04:50,680 --> 00:04:56,379 Actually, at the time when I went to school, there was a course on the BBC teaching Russian and I thought, 43 00:04:56,380 --> 00:05:03,450 Oh, fantastic, that's what you need for a spy. Now you can tell how old I am because I grew up in the Cold War when the Russian fabric. 44 00:05:04,750 --> 00:05:09,340 And so my French teacher help me with the Russian course on the BBC. 45 00:05:10,060 --> 00:05:12,010 But as I wanted to learn these languages, 46 00:05:12,010 --> 00:05:18,500 I more and more frustrated because there were all these kind of strange spellings that you just have to learn. 47 00:05:18,520 --> 00:05:25,329 It was never long term at Learn Irregular Verbs, which is S.A. Cotton to the Russian course was actually a disaster. 48 00:05:25,330 --> 00:05:29,490 I couldn't get past the word hello, which has so many consonants and no vowels. 49 00:05:30,070 --> 00:05:34,890 My strong suit was the name of the cause. I couldn't even say the name of the school said. 50 00:05:35,610 --> 00:05:44,679 So I became very disillusioned. And it was strange to kind of spy and learn all these languages, but it was about that time, about 12 or 13, 51 00:05:44,680 --> 00:05:53,020 that my maths teacher in my school in May, Wilson, just like I want to see you after class, I got into trouble. 52 00:05:53,770 --> 00:05:58,870 So I went off to the end, of course ended and he said, Follow me. 53 00:05:59,050 --> 00:06:05,620 We went round the back of my small car, the whole dropping out, and then he took out his right time. 54 00:06:05,620 --> 00:06:09,100 Cigar. You said you weren't allowed to smoke in the common room. So two guys, right? 55 00:06:09,310 --> 00:06:17,379 So I said the same time, I think you should find out what mathematics is really about because it isn't really about all the kind of multiplication, 56 00:06:17,380 --> 00:06:20,550 percentages, signs and cosines that we're doing in the classroom. 57 00:06:20,800 --> 00:06:24,930 Much more exciting and he recommended a few books to me. 58 00:06:25,360 --> 00:06:32,439 But he's always a rock, this world of mathematics. And so we took this I took this list of books, 59 00:06:32,440 --> 00:06:39,670 and I went home and my dad and I came up and we came to Oxford with this wonderful bookshop called Blackwell's, 60 00:06:40,240 --> 00:06:47,320 which is going to have, you know, your daughter, who, as you know, I think that was taught, is this kind of small shopfront. 61 00:06:47,590 --> 00:06:51,250 Do you think there can't be anything interesting here? You go inside and it just goes on forever. 62 00:06:52,010 --> 00:06:56,829 You go down into the basement and there are all these science books and maths books, and that was so exciting. 63 00:06:56,830 --> 00:07:02,580 And so my dad took this list of books and I was just went round sort of wandering, putting books off the shelves. 64 00:07:02,610 --> 00:07:09,790 I couldn't understand words. You seem to be in some sort of secret code, but there are undergraduate stands of reading up against the bookshelves, 65 00:07:09,790 --> 00:07:13,099 reading these books as if they were novels, little stories and things. 66 00:07:13,100 --> 00:07:16,570 So. So I became very intrigued. It was exciting excitement so much. 67 00:07:16,900 --> 00:07:23,080 And we took these books home and I began to read about this exciting world of mathematics, 68 00:07:23,080 --> 00:07:27,940 and I began to have a sense of the amazing stories that this world contains. 69 00:07:28,330 --> 00:07:35,290 But what intrigued Moses was one of the books that my teacher recommended because it was called The Language of Mathematics. 70 00:07:35,710 --> 00:07:39,370 I still have the book that we bought that Saturday morning. 71 00:07:39,370 --> 00:07:46,060 It costs £1.75. I defy you to find a book in black holes now that costs £1.79. 72 00:07:46,720 --> 00:07:53,170 But this book I know because first of all, I never really thought of mathematics as a language, 73 00:07:55,060 --> 00:07:58,840 but as I began to read this book, I realised, Yeah, it's an amazing language. 74 00:07:58,840 --> 00:08:06,000 It's a language which actually helps us to articulate the structures in the world around us, where we come from, where we're going to go next. 75 00:08:06,460 --> 00:08:11,100 It was one language because I didn't have the irregular verbs that only make perfect sense. 76 00:08:11,110 --> 00:08:18,939 And so this is the language for me. So that's not to say that they didn't have strange twists and turns and surprises, 77 00:08:18,940 --> 00:08:25,330 and that's one of the joys of mathematics that not everything is totally obvious, yet everything seemed to make perfect, logical sense. 78 00:08:25,720 --> 00:08:30,940 And this is the book. It's not a very famous it's been really helpful in language. 79 00:08:30,940 --> 00:08:37,389 Mathematics is a language on the language that really I found so intoxicating in this book was this 80 00:08:37,390 --> 00:08:42,820 man with power who developed to understand the world of symmetry and language through group theory. 81 00:08:43,390 --> 00:08:48,460 And I began to understand when I read these books that in a way, symmetry is its own language. 82 00:08:48,640 --> 00:08:53,560 Symmetry is a language that nature uses to communicate information. 83 00:08:54,040 --> 00:08:57,820 If something has symmetry, then it's generally got a message inside of it. 84 00:08:58,690 --> 00:09:07,419 For example, if you go to the garden and you look at the bumblebee, a bumblebee has incredibly fine vision and can't judge distances. 85 00:09:07,420 --> 00:09:14,979 It sees the world very monochromatic. KLEE But what it can make out is shapes with symmetry because it knows the shape. 86 00:09:14,980 --> 00:09:18,790 The symmetry is likely to be a flower, which will have substance inside it. 87 00:09:19,180 --> 00:09:25,180 Now, intriguingly, the flower itself needs to be to this day in order to propagate is genetic heritage. 88 00:09:25,450 --> 00:09:30,550 So the symmetry of the flower is little bit like a bill saying, you know, come and visit me. 89 00:09:31,180 --> 00:09:39,630 And in fact, research has been done to show that the more symmetrical the flower, the sweeter the nectar inside the bee, inside the flower. 90 00:09:39,640 --> 00:09:48,280 Although we also have become very sensitive to symmetry, I think, you know, we survived in the jungle because of our ability to spot things, 91 00:09:48,310 --> 00:09:55,030 especially if you're in the jungle, you see the chaos of the trees and the leaves and things, and suddenly you see something with mirror symmetry. 92 00:09:55,630 --> 00:10:00,280 You better take notice because that's an animal. Either it's going to eat you or you're going to it. 93 00:10:00,370 --> 00:10:04,330 So symmetry. Those who are sensitive to symmetry somehow survive in this world. 94 00:10:05,200 --> 00:10:09,460 And even now we use symmetry very often when we're choosing a mate. 95 00:10:10,030 --> 00:10:15,880 I'm going to show you two pictures of faces I talk to, just think normally, but I made them artificially symmetrical. 96 00:10:16,120 --> 00:10:23,410 And the bottom line now, if you ask somebody between these two images, which ones do you find the most beautiful? 97 00:10:23,770 --> 00:10:27,430 Most people are drawn to the face, which is most symmetrical. 98 00:10:27,970 --> 00:10:31,690 And why is that? Why we associate symmetry with beauty? 99 00:10:31,900 --> 00:10:35,590 Well, again, symmetry is communicating information. We're looking for a mate. 100 00:10:35,740 --> 00:10:41,050 We're looking for somebody who has very good genetic heritage, good upbringing, good conditions. 101 00:10:41,470 --> 00:10:45,340 And the thing is that symmetry is quite hard to make. It's very easy to break. 102 00:10:45,640 --> 00:10:50,890 And so if you find somebody who has a perfectly symmetrical face that's actually communicating information, 103 00:10:51,250 --> 00:10:55,690 it's communicating information about their genetic background, that they're their upbringing. 104 00:10:55,690 --> 00:11:01,810 And so that's why, again, symmetry is being used in the face to communicate information when you're choosing your mate. 105 00:11:02,650 --> 00:11:05,350 And I rather like quite which comes from Galileo, 106 00:11:05,350 --> 00:11:11,380 which I think rather sums up the power of mathematics as a language to to understand the world around us. 107 00:11:11,440 --> 00:11:18,070 He writes, The universe cannot be raised until we learn the language, become familiar with the characters, which is written. 108 00:11:18,760 --> 00:11:20,650 It is written in mathematical language. 109 00:11:21,040 --> 00:11:29,380 And the letters are triangles, circles and other geometric figures without which means it is humanly impossible to comprehend a single without. 110 00:11:31,220 --> 00:11:38,000 So where do we start to try and explore the world as soon as we go off to the beginning of the 19th century, 111 00:11:38,000 --> 00:11:44,990 developed this language, but actually maybe trying to articulate not a sad world of symmetry for millennia. 112 00:11:45,200 --> 00:11:50,370 In fact, if you go back to some of the very first objects that humans carved out. 113 00:11:50,390 --> 00:11:56,480 So there's a wonderful game in which we find in the British Museum in London. 114 00:11:57,170 --> 00:12:04,129 This game dates back to 2600 B.C. and it's got for the first time, interestingly, 115 00:12:04,130 --> 00:12:10,340 the first ice cubes that we used to play, Monopoly, things like that, but a little tetrahedral ice. 116 00:12:10,910 --> 00:12:19,280 So it's a kindred symmetrical object. The first choice that we used in history were the knuckle bones of sheep, which all are irregular. 117 00:12:19,280 --> 00:12:22,490 They would land. Several are often on one side rather than another. 118 00:12:22,700 --> 00:12:28,790 And people soon realised that if you wanted to find ice, you want something which is symmetrical, which doesn't on one side over the other. 119 00:12:28,970 --> 00:12:34,540 So they were naturally drawn by their claim to produce shapes which had an inbuilt symmetry. 120 00:12:35,060 --> 00:12:42,950 And so the four sides of the novel gradually got carved into this tetrahedron, which is made up of four equal outlines. 121 00:12:43,130 --> 00:12:46,610 Now, interestingly, I like this one and one of the points upwards. 122 00:12:46,880 --> 00:12:55,430 So what's the the they describe this game as they would colour two corners and then you throw it the tetrahedron 123 00:12:56,030 --> 00:13:00,290 and then you count the number of black spots that were pointing out and that would be all new in the game. 124 00:13:00,830 --> 00:13:04,850 And so this game of war actually is one of the forerunners of backgammon. 125 00:13:04,850 --> 00:13:06,500 It's an early version of backgammon. 126 00:13:06,770 --> 00:13:15,649 And even the board itself, you can see some actually the significant squares all have symmetrical shapes attached to them around the same time. 127 00:13:15,650 --> 00:13:19,670 But in Scotland you find other artists playing around with symmetry. 128 00:13:20,030 --> 00:13:25,280 In fact, these stone balls you couldn't find here in Oxford in the Ashmolean Museum, 129 00:13:26,000 --> 00:13:35,420 they make they match 2500 B.C. Every game you can see the artist taking a ball and carving different patches on the side of the ball, 130 00:13:35,420 --> 00:13:38,930 almost like a football, trying to make out of all the different patches. 131 00:13:39,170 --> 00:13:42,680 And you can see the art is exploring different possibilities. 132 00:13:42,680 --> 00:13:48,020 So something like a cube or the tetrahedron or some more complicated shapes. 133 00:13:48,380 --> 00:13:53,510 And it's interesting, we don't actually know what these stones or whether they had a purpose. 134 00:13:53,930 --> 00:13:55,460 They don't seem to be part of the game. 135 00:13:56,270 --> 00:14:03,830 Some have suggested they might have been part of a fortune telling, but it isn't the way they had power for the clans. 136 00:14:04,340 --> 00:14:11,690 But it's facilitating all these 2500 B.C., exploring one possible symmetries that are out there. 137 00:14:11,810 --> 00:14:19,040 And that's somehow what drives mathematics, is that the the the challenge of trying to find what possible symmetries are. 138 00:14:19,700 --> 00:14:27,590 And it really was it wasn't we had to wait until the ancient Greeks for a more analytical analysis of these symmetrical shapes began to emerge. 139 00:14:28,220 --> 00:14:34,730 And in fact, you find in Euclid's elements a proof sort of culmination of this great book. 140 00:14:34,970 --> 00:14:40,760 Is it a proof that you can actually only have five different shapes which make up dice? 141 00:14:41,060 --> 00:14:47,330 It always has a symmetrical face, and you have to have the same symmetrical face about the whole shape. 142 00:14:47,330 --> 00:14:52,640 And they have to arrange such that no faces and this can be distinguished from any other. 143 00:14:53,120 --> 00:14:59,470 With those conditions you find there are only five different possible types and actually place. 144 00:14:59,540 --> 00:15:06,529 I believe that the symmetry so important is that the associated these five basic shapes with the building 145 00:15:06,530 --> 00:15:11,900 blocks of nature we believe in mathematics was the foundation of the whole of the natural world. 146 00:15:12,170 --> 00:15:14,870 And so each of these five shapes is associated with one them. 147 00:15:14,870 --> 00:15:20,450 One of the elements now the elements at of time in the ancient Greeks was things like oxygen and hydrogen, 148 00:15:21,140 --> 00:15:24,260 but with things like fire, earth, air and water. 149 00:15:24,860 --> 00:15:28,189 So fire, the shape of fire was this little tetrahedron. 150 00:15:28,190 --> 00:15:32,179 So the tetrahedron is sometimes spiky, is of all the dice. 151 00:15:32,180 --> 00:15:39,650 And that was the shape of fire. The cube made up of its six square faces that was stable earth. 152 00:15:40,100 --> 00:15:46,610 And then you have another shape made out of rats and triangles. You could put eight equal out to times together to make an octahedron. 153 00:15:47,180 --> 00:15:55,460 That was the shape of this place. As I say to air, you can put 20 faces together, an easy classify move to make an icosahedron. 154 00:15:55,940 --> 00:16:00,500 This is the most circled of the shapes and so Plato associated with water. 155 00:16:00,770 --> 00:16:02,600 And then you had this one shape match over, 156 00:16:03,080 --> 00:16:11,270 which was the dodecahedron beautiful shape made 212 pentagonal faces and he associated this one with the shape of the universe. 157 00:16:11,540 --> 00:16:19,239 At the time, the ancient Greeks believe that somehow the universe was basically just some sort of glass ball with the star painted on it and place. 158 00:16:19,240 --> 00:16:27,229 They believe that that's where we were sitting. Inside was basically just a big dodecahedron and you can find examples. 159 00:16:27,230 --> 00:16:36,260 Actually, again, it's 12 faces. There are no examples of called calendars or with Zodiac signs with these 12 phases. 160 00:16:36,690 --> 00:16:38,030 So, yes, it's interesting. 161 00:16:38,900 --> 00:16:47,690 Now, from a small world perspective, Plato's classification of these shapes associated with the elements as we find what looks kind of ridiculous. 162 00:16:48,020 --> 00:16:52,110 But actually, Plato talked to something very deep about symmetry. 163 00:16:52,250 --> 00:16:59,420 So there was this symmetry. There is symmetry absolutely at the heart of science and the natural world. 164 00:16:59,990 --> 00:17:08,050 So, for example, in chemistry, chemists learn about different ways that molecules can be put together as way. 165 00:17:08,840 --> 00:17:16,970 So the different credit, the way that crystals behave of crystal structures, is very often dependent on proteins or symmetry. 166 00:17:17,540 --> 00:17:23,820 The biologies also in biology don't really want to guess because nobody knows. 167 00:17:24,290 --> 00:17:29,420 Generally, viruses like herpes virus or the AIDS virus based on symmetrical shapes. 168 00:17:29,690 --> 00:17:36,319 In fact, that virus is using the fact that symmetry has a very simple rule to create the object. 169 00:17:36,320 --> 00:17:45,590 It's not a very complicated object. So virus is heart broken has a very short is of RNA or DNA, which is a program to reproduce itself. 170 00:17:45,620 --> 00:17:48,020 It needs to reproduce itself as quickly as possible. 171 00:17:48,410 --> 00:17:54,059 And so the fact that a symmetrical shape is a very false shape to make with the very simple program is probably at 172 00:17:54,060 --> 00:18:02,480 the heart of why the virus is choosing to use this sort of a very stable shape and a very strong shape as well. 173 00:18:03,110 --> 00:18:09,800 And so we've begun to understand the way that viruses work. Understanding online symmetry in physics as well. 174 00:18:09,890 --> 00:18:13,160 And what's happening in a Large Hadron Collider, 175 00:18:13,490 --> 00:18:18,319 the fact that we're able to predict new particles that combined in there to make 176 00:18:18,320 --> 00:18:22,160 sense of all this kind of menagerie of particles that we've discovered so far. 177 00:18:22,430 --> 00:18:30,470 Actually, this horse is a simple object in very high dimensions, which somehow makes sense of all of these strange objects that we discovered. 178 00:18:30,890 --> 00:18:34,220 And also that helps us to to make predictions about what's missing. 179 00:18:34,430 --> 00:18:40,580 Because if one of the pieces isn't represented, there's likely to be a particle and we can look for it will correspond to that face. 180 00:18:40,880 --> 00:18:48,350 So symmetry is all over the scientific world, but essentially symmetry is very much part of the artistic as well, 181 00:18:48,890 --> 00:18:53,960 although I think all of these have a slightly more ambiguous relationship with symmetry. 182 00:18:54,530 --> 00:19:03,410 This is Thomas Mann in the Magic Mountain, talking about the symmetry of a snowflake, and they might be a shot at precision. 183 00:19:03,690 --> 00:19:11,120 And it definitely the very marrow of death, I think for all this symmetry is something they're a little bit nervous of. 184 00:19:11,120 --> 00:19:12,259 It's very restrictive. 185 00:19:12,260 --> 00:19:22,460 It tells you what should happen and and just like how it somehow can be filled with a sense of something without life and energy to it. 186 00:19:22,850 --> 00:19:26,419 But I think there are some artists who really love revelling in symmetry. 187 00:19:26,420 --> 00:19:33,500 And one of the parts, and particularly taps into symmetry and fantastic I think is music and in particular the music of ball. 188 00:19:33,530 --> 00:19:39,630 For example, the Goldberg Variations, I think is almost like a song celebrating symmetry. 189 00:19:39,640 --> 00:19:43,000 So here's a little bit of one of the variations from Bach, Soledad. 190 00:19:43,040 --> 00:20:02,699 Variations. Now the variations actually start with an aria, very simple aria. 191 00:20:02,700 --> 00:20:09,150 And then there are three variations through to that all study, which is the reputation of the aria you saw. 192 00:20:10,050 --> 00:20:15,810 Now, interestingly, so there's sort of a circle going on there already because the two actually got one means to the other. 193 00:20:16,020 --> 00:20:22,379 And you go to the 16th variation, Bach pulls out a banjo, which usually is the beginning of a musical piece. 194 00:20:22,380 --> 00:20:25,100 So it really got the sense with this piece. 195 00:20:25,350 --> 00:20:34,079 So all four ends and there's a sense, a circle already there that everything that variation Bach makes a hand out of the variation. 196 00:20:34,080 --> 00:20:39,000 So a kind of you might remember from singing in school when all this all starts off the song. 197 00:20:39,000 --> 00:20:42,479 And then a little bit later, the other half of the class joins in. 198 00:20:42,480 --> 00:20:48,090 And you have to tune and the same tune, guys, with the different times and you get this lovely interaction. 199 00:20:48,360 --> 00:20:52,700 So Bach loved the idea of canons, but he wanted something slightly more sophisticated. 200 00:20:52,710 --> 00:20:58,200 So each new canon, actually the second voice when it comes in doesn't just repeat with the first, 201 00:20:59,100 --> 00:21:03,060 but I think the set up was so soft, higher and higher and higher. 202 00:21:03,240 --> 00:21:09,110 So actually, by the eighth variation, what happens is that you guess the second voice comes in an octave away. 203 00:21:09,480 --> 00:21:11,730 Now I don't even want to says, I know you started with. 204 00:21:11,730 --> 00:21:17,280 So again, you just kind of set the pattern happening in the canon, so almost even has a spiral shape. 205 00:21:17,640 --> 00:21:21,290 And so for me on hearing this, there's a embedded inside the structure. 206 00:21:21,310 --> 00:21:28,080 This this is what we call a chorus of circles where the circles inside the structure of this piece and again, 207 00:21:28,080 --> 00:21:33,180 you know, the rhythms ball is very careful to to get all the different rhythms that are possible. 208 00:21:33,180 --> 00:21:35,129 So in the in the canons, 209 00:21:35,130 --> 00:21:44,040 the variations are broken off sometimes reasonable or reasonable or do these in them are the beats and divided into quavers, triplets or quavers? 210 00:21:44,340 --> 00:21:48,510 And what about going through the symmetries that if the two triangles are combination? 211 00:21:49,170 --> 00:21:58,260 He makes sure that each hand covers one of the possibilities either three B's and of all divide it up into seven quavers and Bach, 212 00:21:58,260 --> 00:22:03,570 the true imputation. Make sure that each and every different possibilities he is covered in brackets. 213 00:22:04,350 --> 00:22:09,810 Ball student medicine used to call box music a process, a sound in mathematics. 214 00:22:09,930 --> 00:22:15,330 And Bach isn't the only one who has lots of ideas symmetry in order to create variations. 215 00:22:15,510 --> 00:22:20,900 Very often the variations will mirror what is going on before when you were trying to push. 216 00:22:20,910 --> 00:22:26,129 And so symmetry is very often something you can hear embedded inside the music of, for example, 217 00:22:26,130 --> 00:22:31,830 Bach and another of the also I think, which uses symmetry or lost its architecture. 218 00:22:32,970 --> 00:22:38,870 We're in a building which really mixes art and mathematics here, police officers. 219 00:22:39,390 --> 00:22:43,050 We're right back to, in ancient times, the pyramids. In Egypt, for example. 220 00:22:43,230 --> 00:22:50,830 I looked we like these all Hadrian's Wall one hall stuck inside of the fence and he squares right through to modern day Paris. 221 00:22:50,980 --> 00:22:55,430 I think Paris is one of my favourite cities full of symmetry in fact. 222 00:22:55,430 --> 00:23:04,010 So the revolutionaries of the time of Galba had wanted to build a sphere at a hall to Paris because they felt that a sphere was 223 00:23:04,020 --> 00:23:13,410 a shape which represented the idea of égalité no direction favoured and over any other sort of perfectly symmetrical building. 224 00:23:13,830 --> 00:23:20,910 But since quite difficult to build architecturally on this one, eventually you'll be able to school Agios in Metz in Paris. 225 00:23:21,690 --> 00:23:29,350 I think the revolutionaries of debate just wanted to point out that this is in fact an all maximal revolutionary idea. 226 00:23:29,370 --> 00:23:37,620 But if you go to Israel, you actually find amazing blocks of flats which are based on the dodecahedron shape. 227 00:23:37,870 --> 00:23:41,759 The place you associate with the shape universe and solar panels is in Iran, 228 00:23:41,760 --> 00:23:48,210 not in Israel, although I'm told that these are hopeless furniture that I see. 229 00:23:48,600 --> 00:23:52,230 I went very closely with a mathematician in Japan called Professor Corncob, 230 00:23:52,470 --> 00:23:57,870 and I went out to all my studies and symmetry to go and do this work with him. 231 00:23:58,050 --> 00:24:04,470 And Professor Kurokawa took me up to his beautiful city, which I don't know whether any of you need to measure, 232 00:24:05,100 --> 00:24:09,660 which is full of all these beautiful Shinto shrines and Buddhist temples, 233 00:24:10,110 --> 00:24:14,310 and they're full of symmetry all over the place, the patterns inside the building. 234 00:24:14,490 --> 00:24:16,110 And as you all know, we took this photograph. 235 00:24:16,560 --> 00:24:23,500 We we climb the stairs to this archway and the Australia had these beautiful columns in these symmetrical designs. 236 00:24:24,390 --> 00:24:29,370 So eight columns exactly the same, except for one, which is turned upside down. 237 00:24:29,850 --> 00:24:34,190 And I said to Professor Kurokawa, Oh my gosh, that the architect must be very angry. 238 00:24:34,210 --> 00:24:37,830 The builders, I mean, go that one wrong. It's upside down. And this is not it. 239 00:24:37,860 --> 00:24:45,000 It was a very deliberate decision because in Japanese they love setting all these expectations and then embracing. 240 00:24:45,270 --> 00:24:50,309 And he referred me to this lovely book called The Japanese Essays in Idleness. 241 00:24:50,310 --> 00:24:53,670 What a wonderful title for a book from the 14th century. 242 00:24:54,150 --> 00:25:01,110 And he revealed this particular requirement on these. And then one thing uniformity is undesirable, leaving something incomplete. 243 00:25:01,390 --> 00:25:04,600 Interesting, given the feeling there is room for growth. 244 00:25:05,130 --> 00:25:09,610 Even when building the Imperial Palace, they always leave one place unfinished. 245 00:25:10,240 --> 00:25:15,310 Nancy even if you go back to the ball. Ball. GOLDBERG Variations seem to be full of symmetry. 246 00:25:15,640 --> 00:25:20,140 You reach the third variation. You sort of think you know exactly what's going to happen next. 247 00:25:20,470 --> 00:25:24,040 And then back to exactly the same thing turns the whole thing upside down like that. 248 00:25:25,210 --> 00:25:31,430 It's going to call it a musical check that this variation has absolutely nothing to do with the rest of the structure, too. 249 00:25:31,660 --> 00:25:37,209 And it's such surprise because you write it and then suddenly realise how much symmetry 250 00:25:37,210 --> 00:25:42,460 there being on that point that you appreciate that break in symmetry involved in that. 251 00:25:43,700 --> 00:25:49,880 But I think actually if I was going to be cast out, I had to leave the rest of my life in one building across the well. 252 00:25:49,910 --> 00:25:59,660 Being somebody who studies symmetry and love symmetry, I probably would choose the Alhambra in Granada because, you know, Hungary was not a palace. 253 00:25:59,660 --> 00:26:04,700 There was really a past century symmetry, this symmetry all over the place. 254 00:26:05,150 --> 00:26:10,640 There's lots of water throwing up reflections of the buildings in the water. 255 00:26:10,760 --> 00:26:22,280 They came to realise how, how, how special symmetry is because it was a little breath of wind for that symmetry suddenly to be shattered. 256 00:26:22,490 --> 00:26:29,000 So it's something very special. But I think it's funny, the walls where I really see symmetry being celebrated. 257 00:26:29,000 --> 00:26:33,470 So because all of these beautiful symmetrical tiles they use across the walls 258 00:26:33,890 --> 00:26:38,690 here in the offices exploring all the different possibilities that they have, think of the two candles. 259 00:26:39,110 --> 00:26:44,810 And actually, I think you see in the Alhambra, which is really where you can ask the really big questions about symmetry. 260 00:26:45,200 --> 00:26:49,100 Reporter What is a tree? What water? 261 00:26:49,310 --> 00:26:56,090 What does it mean to say that something is symmetrical? How can you say two things have the same symmetry. 262 00:26:56,690 --> 00:27:01,670 How do you understand if you actually around all the different symmetries that are possible? 263 00:27:02,600 --> 00:27:11,060 And as you go on to body language, you want more symmetry is is really what what Galileo's young revolutionary French mathematician did. 264 00:27:11,780 --> 00:27:18,670 I think there's a sort of feel that symmetry is all about that fine, rational symmetry, but there is so much more to this language. 265 00:27:18,680 --> 00:27:26,389 And it's what the guy, along with the one who was able to articulate where the symmetry and actually how I like to describe it is that 266 00:27:26,390 --> 00:27:35,300 symmetry is kind of something that you can do to an object such that when you finish doing something that will, 267 00:27:35,520 --> 00:27:40,850 it looks kind of like the tape we started with in a way, I kind of call it the magic trick. 268 00:27:41,090 --> 00:27:47,150 So if I give you, for example, if I show you this tetrahedron, what are the symmetries of this tetrahedron? 269 00:27:48,080 --> 00:27:51,500 Well, there's some moves that I can make to this tetrahedron. 270 00:27:52,160 --> 00:27:55,550 Sasha, when I made the move, it looks like it did before I saw it. 271 00:27:55,580 --> 00:27:59,660 So, for example, I could pick it up and I could do that. 272 00:28:00,710 --> 00:28:04,610 Now it looks like it did before I saw it. So that is a symmetrical move. 273 00:28:04,820 --> 00:28:10,280 So I like school symmetry, but I mean, I and you show your eyes, which are your eyes? 274 00:28:10,790 --> 00:28:17,700 Now I'm going to do something to this and open them. Now the tetrahedron looks like it did before you shut your eyes. 275 00:28:17,720 --> 00:28:22,120 But I did something to that which has this is one of these symmetries. 276 00:28:22,130 --> 00:28:27,980 So that's what I want you to think is symmetry is something you do to an object which brings it back to look like it did before. 277 00:28:27,980 --> 00:28:35,840 But actually it has changed something. So let's go to the walls in the Alhambra and try to understand these what symmetry really means. 278 00:28:36,350 --> 00:28:42,890 So, for example, this wall here, where's the symmetry here? Well, how we picked up the tiles and put them back down here. 279 00:28:43,370 --> 00:28:52,010 So if they look like for I move them. So I fix the tiles at this red point, pick them up and turn them by 90 degrees, pull them back down again. 280 00:28:52,400 --> 00:28:56,810 The tiles look like they were before I move them and that is a symmetry. 281 00:28:57,110 --> 00:29:05,600 So symmetry or all the structure is something that I can do to the objects, which means in some way makes it look like it did before I moved it. 282 00:29:06,350 --> 00:29:09,520 So I can take two very simple objects and we can do a small. 283 00:29:09,530 --> 00:29:13,730 So what are the symmetries that are made of these tools? 284 00:29:13,880 --> 00:29:17,300 So I'm going to take the object, a triangle and a 6.2. 285 00:29:17,300 --> 00:29:21,520 So I put a little twist off. So let's start with the six point itself. 286 00:29:21,560 --> 00:29:27,330 So for me, symmetry things. I can do movies, but it looks like you did before I knew this. 287 00:29:27,340 --> 00:29:31,070 So I put it together so I can keep track of what we're doing. 288 00:29:31,280 --> 00:29:35,020 So I can take the ten, put it back down again. And it looks like it did before we saw it. 289 00:29:35,030 --> 00:29:41,620 So that's one symmetry. Okay, well, I can move it by a third so I can take it around to see. 290 00:29:41,630 --> 00:29:51,110 So that's two symmetries. I can rotate it by half for 10 seconds, around two days as a third symmetry, I can do it by two thirds a turn. 291 00:29:54,030 --> 00:30:00,089 As for cemeteries and finally I can tell you do away rounds to five six to the fence of 292 00:30:00,090 --> 00:30:06,360 a565 moves that I'm going to make to this object such that it fits back down in size. 293 00:30:06,990 --> 00:30:10,979 Now there is a cemetery. Does anyone have an idea of six cemetery? 294 00:30:10,980 --> 00:30:15,600 I miss that. Yes. Second around the back to it. 295 00:30:15,870 --> 00:30:19,499 Yes, exactly. In fact, that's just leaving it where it is, isn't it? 296 00:30:19,500 --> 00:30:22,850 Because I could take it all the way round and then it hasn't moved at all. 297 00:30:22,860 --> 00:30:27,780 It's not so. So the same symmetry, he's actually just picking it up and put it back down here. 298 00:30:28,320 --> 00:30:33,210 Okay. You might say that's awesome, but actually it's a bit like zero zero. 299 00:30:33,510 --> 00:30:37,889 It's a very difficult concept as a number for mathematicians to get hold of because what's it counting? 300 00:30:37,890 --> 00:30:43,350 It isn't counting anything. So I want you to think of this as a like zero six, but everything has a symmetry. 301 00:30:43,350 --> 00:30:45,660 So zero is you just leave it all in. 302 00:30:45,670 --> 00:30:51,540 Even if you go to this of the irregular face, you see some symmetry which is just leaving the face levels, which is good. 303 00:30:51,750 --> 00:30:55,049 So I we say there are six symmetries there is going to break through for quite a 304 00:30:55,050 --> 00:31:00,030 while to think of just leaving it as a six symmetry and you can't pick the seven, 305 00:31:00,150 --> 00:31:02,840 for example. That might have been one of your other thoughts that it has. 306 00:31:03,090 --> 00:31:07,799 It hasn't got a reflection of symmetry, because if I flipped over, it's pointing the other way. 307 00:31:07,800 --> 00:31:12,630 So it hasn't got another symmetry coming from reflection, however, I won't take the triangle instead. 308 00:31:12,840 --> 00:31:17,760 This does have what is called two rotation symmetries. I'm going to rotate my third clockwise. 309 00:31:17,950 --> 00:31:20,190 I want to rotate my third anticlockwise, 310 00:31:20,370 --> 00:31:25,469 but now I've got refraction so I can take the triangle flipped over and I'm going to go three ways I can do that. 311 00:31:25,470 --> 00:31:30,330 I can flip it over through the line, through X or get it over through the line through y. 312 00:31:30,600 --> 00:31:34,320 So the X is in point swap or I could fix it and put it over there. 313 00:31:34,620 --> 00:31:42,149 So that's five different symmetries. Again, two rotations for three reflections and then I six symmetry, which is just leave me where it is. 314 00:31:42,150 --> 00:31:51,299 I pick it up, put it back down again. So it's got six entries. So this is quite interesting because these two objects both have six symmetry. 315 00:31:51,300 --> 00:31:56,490 So perhaps we should say they have the same symmetry because they have the same amount of symmetry. 316 00:31:57,450 --> 00:32:02,730 But what I want is to explore why actually these two how we articulate really that no, 317 00:32:02,790 --> 00:32:06,210 these, these objects are two genuinely different symmetrical objects. 318 00:32:06,450 --> 00:32:11,130 But before I did I say a little challenge, which I want you to think about through the rest of the lecture, 319 00:32:11,140 --> 00:32:16,270 not, not see that this is the other stuff, but now you've got some idea of magic for me. 320 00:32:16,360 --> 00:32:19,530 So I want you to, to consider another object. 321 00:32:19,560 --> 00:32:22,650 I want you to consider the Rubik's Cube. Rubik's Cube. 322 00:32:22,650 --> 00:32:26,730 So what does symmetries of the Rubik's Cube? Well, think about this magic trick. 323 00:32:26,880 --> 00:32:30,690 So no colours. I don't care, of course, but a symmetry in the cube. 324 00:32:30,690 --> 00:32:35,280 It's really just anything I can do to the cube, which makes it look like still cube. 325 00:32:35,640 --> 00:32:38,910 So I could do that fancy symmetry. Or I could do that. 326 00:32:38,910 --> 00:32:42,190 That's. That's. And that's enough. 327 00:32:42,970 --> 00:32:46,960 So what I want you to think about, there'll be a prize for the person who gets places. 328 00:32:47,200 --> 00:32:53,740 How many symmetries do you think this thing has? How many different, genuinely different moves could I make to this cue? 329 00:32:54,370 --> 00:32:57,819 Such it still looks like a cue. We'll come back to that later. 330 00:32:57,820 --> 00:33:07,270 And I've got a price with this in this case. But so let's come back to these two shapes, because the real breakthrough got along. 331 00:33:07,630 --> 00:33:16,720 First of all, to think of of of symmetry is something about motion as you went very much against what Thomas Mann but for Thomas Mann, 332 00:33:16,720 --> 00:33:20,690 symmetry was something deathly something which didn't move but actually got lost. 333 00:33:20,690 --> 00:33:24,190 And now you should think about symmetry as something with lots of movements in it. 334 00:33:24,250 --> 00:33:30,790 It's all about it's all about life. It's all about the things that you can do as an object, which it looks like it did before I knew it. 335 00:33:31,480 --> 00:33:36,790 But the second great breakthrough was that he realised it isn't just the individual symmetries that are important, 336 00:33:37,480 --> 00:33:42,020 but how they interact with each other. So what do I mean by that? 337 00:33:42,050 --> 00:33:47,600 Well, if you think about it, if I do a magic trick, move to shape, then I can do another move to it. 338 00:33:47,870 --> 00:33:51,650 And then the combined effect is actually a third magic trick. 339 00:33:51,920 --> 00:33:56,360 So actually, all of these things are related. If I do one move followed by another. 340 00:33:56,570 --> 00:34:00,110 The combined effect is is divided in a third symmetrical move. 341 00:34:00,500 --> 00:34:07,610 So in fact, Galois began to explore, okay, what was the relationship between the 66 symmetries of the sixth point you saw? 342 00:34:07,800 --> 00:34:12,180 What's the relationship between all of those symmetries? If I do one followed by another. 343 00:34:12,200 --> 00:34:15,650 It's got to be a third symmetry, so it must be one on that list. 344 00:34:15,980 --> 00:34:18,500 So I can two names to all of these symmetrical moves. 345 00:34:19,010 --> 00:34:28,280 So the name Amy goes to just leaving the thing where it is correct to be moving it by a sixth, but to see a third of a and so on. 346 00:34:28,880 --> 00:34:34,070 So now let's see what happens if I combine a six of inside followed by ten. 347 00:34:34,460 --> 00:34:40,710 So I'm going to do I'm going to do count will be first is equal to ten and I'm going to do capital C a third. 348 00:34:41,240 --> 00:34:47,210 So we do a combined effect and this is what this table records, sixth of a term followed by a third of a time. 349 00:34:47,450 --> 00:34:50,690 Well, the combined effect is actually about the same half term in one go. 350 00:34:51,500 --> 00:34:55,760 So actually, this kind of algebra, a language hiding behind these symmetries, 351 00:34:55,760 --> 00:34:59,600 which says, if I can combine two sentences, it's going to be a third symmetry. 352 00:34:59,600 --> 00:35:02,910 And this table records for you how these symmetries interact. 353 00:35:02,930 --> 00:35:07,790 So the combination of being followed by C is actually the same as just in the half step. 354 00:35:08,300 --> 00:35:11,430 Now I want to look do it in the other order with a three mass. 355 00:35:11,450 --> 00:35:14,509 I could have done the third return first, followed by the same for the turn. 356 00:35:14,510 --> 00:35:17,930 And still I get half as it really doesn't matter. What do you do? 357 00:35:18,230 --> 00:35:23,510 And in fact, you can see that reflected in this table. The table records all of the different pairs of symmetries. 358 00:35:23,510 --> 00:35:27,410 And what the effect is, is the symmetry. Whatever you. Doesn't matter what order you do. 359 00:35:28,640 --> 00:35:31,820 However, if we come to the triangle, it does matter. What will you do? 360 00:35:32,060 --> 00:35:39,110 So I'm going to do a third button clockwise that's going to be you go and you follow by flip and the reflection in X, 361 00:35:39,260 --> 00:35:42,980 the combined effect is actually as if the triangle was relaxing it. 362 00:35:43,310 --> 00:35:49,880 But if we do it in a different order, let's do the reflection in experts and then the rotation by third anticlockwise. 363 00:35:50,690 --> 00:35:55,070 Actually, that's the triangles ended up in a different place. It's a table like reflected in Y. 364 00:35:56,090 --> 00:36:01,130 If I. If it is if it goes to the part later, I want you to take a b-max and look at the picture on the bottom. 365 00:36:01,310 --> 00:36:06,670 And then what I want you to do is do a 90 degree turn clockwise and then a reflection in a line away from you, 366 00:36:06,780 --> 00:36:12,829 and then see when the picture is pointing, put it back, back to where it was, and then do the reflection first and then a rotation. 367 00:36:12,830 --> 00:36:18,770 You find that the picture is pointing in the other direction. So here it matters what order you do the symmetries in. 368 00:36:19,100 --> 00:36:26,120 And so it's the way the symmetries interact that we're able to start to distinguish why the symmetries of the triangle that genuinely difference, 369 00:36:26,130 --> 00:36:33,020 the symmetries, all the six points are. In fact, what I want about was a set of rules for the way the symmetries interact. 370 00:36:33,320 --> 00:36:37,130 And he shows that it's an object with six symmetries. 371 00:36:37,340 --> 00:36:42,950 Either the six symmetry must behave like the 6.2 starfish, or they must behave like the triangle. 372 00:36:43,190 --> 00:36:46,620 And there isn't a third symmetrical object. It will either. 373 00:36:46,620 --> 00:36:50,600 The symmetry will interact in the same way as one of these two objects. 374 00:36:51,350 --> 00:36:57,680 So suddenly this language now you've enabled him to say, Yeah, actually there are only two symmetrical jets with six symmetries. 375 00:36:58,100 --> 00:37:02,389 If I could use this language, it's a bit like a set of rules for Sudoku, for example. 376 00:37:02,390 --> 00:37:09,560 Let me do it. Inside the body of this table, you never see a symmetry twice in a line or in a corner. 377 00:37:09,980 --> 00:37:13,910 And so Galileo developed some set of rules to the way symmetries must interact, 378 00:37:14,090 --> 00:37:18,350 which helps him to then explore, for example, symmetries in the Alhambra. 379 00:37:18,590 --> 00:37:22,340 So it took actually till the end of the 19th century for us to use Galois language. 380 00:37:22,730 --> 00:37:26,900 But for example, these tools here, these two always look very different. 381 00:37:27,230 --> 00:37:33,170 One is made up of these kind of shimmering triangles, the other six point to solve these shapes. 382 00:37:33,380 --> 00:37:40,430 But actually using Galileo's language, we can say that these two tilings actually represent the same group of symmetries. 383 00:37:40,880 --> 00:37:44,450 So where all the symmetry decided, let's take a guess and measure moves. 384 00:37:44,750 --> 00:37:48,950 So there's one point where I can rotate by six and ignore the colours. 385 00:37:49,130 --> 00:37:53,150 So think of a turn to the point where all the triangles meet. That's one symmetry. 386 00:37:53,330 --> 00:37:58,540 There's another symmetrical move I can make, which is to take the points in the middle of the triangles, rotate one third of the time, 387 00:37:58,730 --> 00:38:06,410 the sun will look down on top of each other, and then an isolated corner place is fine, but halfway along the edge you can flip these by half a turn. 388 00:38:06,620 --> 00:38:11,719 And so what happens now is that the triangles sort of swap places on top of each other. 389 00:38:11,720 --> 00:38:15,950 So the white triangle went to the blue and blue went and said once and that's a third move. 390 00:38:15,950 --> 00:38:21,020 So basically these are the ingredients and all the symmetries of this particular set of toys. 391 00:38:21,350 --> 00:38:25,550 But if we go to the other wall, which I showed you, well, the same moves work here. 392 00:38:25,730 --> 00:38:29,720 There's a six out of a ten you can make at the centre of a six pointed star. 393 00:38:30,350 --> 00:38:35,030 There's a fair return. If you look where the pieces meet, you can rotate by a third return there. 394 00:38:36,020 --> 00:38:40,130 So that's point there. And then again, after you take the halfway point between six. 395 00:38:40,250 --> 00:38:43,850 Point in stores. That's another place where you can make these rotations. 396 00:38:44,150 --> 00:38:49,040 So although these pictures look completely different, actually using our language, 397 00:38:49,040 --> 00:38:53,719 we can articulate the symmetries of these two walls or exactly the same facts. 398 00:38:53,720 --> 00:39:01,070 In this case, we can put one tiling on top of another, and any move that we made to one will actually represent the symmetry of the other. 399 00:39:01,730 --> 00:39:02,390 So these two, 400 00:39:02,630 --> 00:39:09,620 I think you're going to think of Gauloises work a little bit like the concept of number and the concept of number is quite an abstract idea. 401 00:39:10,040 --> 00:39:14,180 For example, level three people in the front row here sitting in three chairs. 402 00:39:14,510 --> 00:39:20,210 Now the people of right difference the chairs, but the abstract idea of the number three is common to both. 403 00:39:20,960 --> 00:39:26,480 So symmetry, I want you to think of it in a similar way. It's not about geometry in pictures. 404 00:39:26,630 --> 00:39:30,380 These two pictures that I showed you, they have the same underlying symmetries, 405 00:39:30,380 --> 00:39:36,470 but they're different representations of those symmetries just in the same way as we got different representations of the number three. 406 00:39:36,910 --> 00:39:41,360 So it enables us to take, for example, these three different images. 407 00:39:41,360 --> 00:39:46,430 There's one is the tilings, the entrance to the Alhambra, one's the floor, one's the ceiling. 408 00:39:47,120 --> 00:39:52,700 Actually, these will have the same symmetrical moves that can be made, all of them, although the pictures look very different. 409 00:39:53,000 --> 00:39:59,690 This is a symmetry for 14. It's nothing to do with football but to do with the fact that there's a place where you can do a quarter of a turn. 410 00:39:59,810 --> 00:40:02,100 Another place? A quarter of a ten and a half of ten. 411 00:40:02,990 --> 00:40:09,110 So this language suddenly gave us a way to articulate when two different things might look very different, 412 00:40:09,110 --> 00:40:17,180 actually have the same underlying symmetries. By the end of the 19th century and allowed us to actually articulate the fact that in the Alhambra, 413 00:40:17,600 --> 00:40:24,650 there are only 17 different sorts of underlying sentences that you can make on a two dimensional wall. 414 00:40:25,400 --> 00:40:27,410 And if you think about those pictures of Escher, 415 00:40:27,530 --> 00:40:34,489 as he was very inspired by his trips to the Alhambra and he made lots of different pitches with devils and angels, 416 00:40:34,490 --> 00:40:43,010 a little selfish and efficient garden. But actually we can prove mathematically that however, on Escher drawings or anyone else, 417 00:40:43,010 --> 00:40:47,330 they will never be able to find anything more than the 17 that are on this list. 418 00:40:47,690 --> 00:40:53,710 And interestingly, what I do these in community holidays is my family, which they hate. 419 00:40:53,720 --> 00:40:55,730 But I took them to the Alhambra and I said, okay, 420 00:40:55,760 --> 00:41:01,489 we can see where they actually found 17 different symmetries in the Alhambra and they almost stayed there. 421 00:41:01,490 --> 00:41:06,830 The last one is Sol three, three, three, and those blue tiles, we need to paint those black. 422 00:41:06,950 --> 00:41:11,770 And then we would have had an indication that we didn't actually see this abstractly. 423 00:41:11,780 --> 00:41:18,439 But but it's amazing. That's actually even the artist was kind of ahead of the mathematicians in being able to find all of these. 424 00:41:18,440 --> 00:41:24,320 But it was only with mathematics that we're able to articulate the sort of limits of this world of symmetry. 425 00:41:25,670 --> 00:41:33,220 The only thing Gabor did was to actually realise that symmetry also has a kind of atomic symmetries, 426 00:41:33,240 --> 00:41:37,040 a bit like the possibility the periodic table of symmetry. 427 00:41:37,250 --> 00:41:41,400 Now, I think it's actually extraordinary and I studied Galileo to realise this. 428 00:41:42,210 --> 00:41:50,360 This man, aged 20, had come up with so many amazing ideas and this is perhaps the most savvy one because he showed why a 429 00:41:50,360 --> 00:41:56,810 symmetrical object can actually be broken down into the symmetries of smaller atomic symmetrical objects. 430 00:41:57,620 --> 00:42:02,720 And this gave us a way in somehow really get to grips with the world of symmetry mathematically. 431 00:42:03,020 --> 00:42:05,900 So, for example, here's a 15 sided coin. 432 00:42:06,200 --> 00:42:13,520 The symmetries in that 15 sided point, you now know how to do their sort of rotations of a 15 sum to four things and things like that. 433 00:42:13,790 --> 00:42:23,210 But actually, you can make the symmetry of this 15 sided coin at the centrepiece of two options, namely a pendulum and applying so and so on. 434 00:42:23,690 --> 00:42:30,800 So actually symmetries of the paintings. I do think that I can do all of them by doing Symmetries of the Pencil, a triangle. 435 00:42:31,040 --> 00:42:36,290 For example, I want to rotate the Pentagon by 50 return. 436 00:42:36,290 --> 00:42:41,170 So the key here is the fact that 15 can be broken down into the Primes three and five. 437 00:42:41,660 --> 00:42:48,920 So let's say I want to rotate by 5610. So I want to get let's say we're going to get six green dots. 438 00:42:48,920 --> 00:42:53,580 515 is the ten. I want to get it to yellow. I'm going to use the symmetry, symmetries, the triangle, the principle. 439 00:42:53,930 --> 00:42:57,980 So I'm going to take over the pendulum. I'm going to rotate by 2/5 to the 10th. 440 00:42:58,280 --> 00:43:00,710 So my brain is going to go down to the blue dot, 441 00:43:01,070 --> 00:43:06,860 but now I'm going to let the triangle take over and I'm going to do a rotation, my third return and equalise. 442 00:43:07,220 --> 00:43:15,860 And then also the combination of those two, hey presto, I've got a 15 for this year and this basically is at the half of all of the symmetry. 443 00:43:16,070 --> 00:43:18,139 You say any symmetrical object, actually, 444 00:43:18,140 --> 00:43:25,210 you'll be able to find smaller symmetrical objects inside of it whose symmetries can be used to build out the symmetries of the large objects. 445 00:43:25,670 --> 00:43:31,790 If you just like two dimensional flat shapes like this, basically it's the primes which are the atomic shapes. 446 00:43:32,240 --> 00:43:39,020 So any shape of 105 sides, you can make that out of triangle Pentagon 675 theta. 447 00:43:39,650 --> 00:43:47,720 So it may. Daniel's discovery that he could do this gave us the idea that you could produce a periodic table of symmetry. 448 00:43:47,870 --> 00:43:53,510 Now we can try to classify what all of these building blocks are symmetry on to understand the whole of the symmetrical world. 449 00:43:54,470 --> 00:43:59,390 So. So already we found the primes of their prime sided shapes of some of the building blocks. 450 00:43:59,780 --> 00:44:05,630 It turns out they're not the only ones. In fact, there are some much more exotic, little more complicated ones. 451 00:44:05,930 --> 00:44:16,670 And intriguingly, the first sort of interesting prime shape in all this is the symmetries of the icosahedron. 452 00:44:16,970 --> 00:44:20,410 Well, actually, not to say that usually the only considering you need to put a slight twist on it. 453 00:44:20,420 --> 00:44:28,820 So this is actually a chocolate box that Escher designed for a manufacturer in Holland of celebrating an anniversary. 454 00:44:29,390 --> 00:44:35,660 When I retire, I want one of these boxes asking you to go to the SWC and Den Haag. 455 00:44:35,840 --> 00:44:43,010 They've got an example, I presume, that makes many of these and the little tin boxes, but they're the most beautiful things. 456 00:44:43,010 --> 00:44:50,540 And but the symmetries of this box are actually one of the first sort of non obvious point symmetries that you can have, 457 00:44:50,720 --> 00:44:58,610 because actually, how many symmetries is this object have? Well, actually, it's the same as the centuries old football. 458 00:44:59,060 --> 00:45:04,420 So the football his football made out of pentagons and and hexagons. 459 00:45:04,430 --> 00:45:09,410 But actually, the symmetries of this are the same as the symmetries of the icosahedron. 460 00:45:09,420 --> 00:45:12,499 So how many different moons on that? I'll call with Max Lucas. 461 00:45:12,500 --> 00:45:18,060 Exercise. Quite a twist. So he's twisted this starfish, so there isn't the reflection, like my 620 starfish. 462 00:45:18,470 --> 00:45:22,430 So how many different moves on there that I can make? You know, I can I can do that. 463 00:45:23,360 --> 00:45:31,640 So I'm just looking to read things all like you find it when you do this, you can do 60 different moons, 60 different symmetries of this shape. 464 00:45:32,410 --> 00:45:35,480 Now, come on, 60. That's an incredibly divisible number. 465 00:45:36,830 --> 00:45:40,410 The reason the Babylonians use it for the base of the nervous system, because it's so obvious. 466 00:45:40,520 --> 00:45:49,040 It's the reason we have 60 minutes in the air. So but when you consider the symmetries of this object, it turns out that number 60 is very invisible. 467 00:45:49,310 --> 00:45:54,230 Actually, the symmetries of this can't be divided into smaller symmetrical objects. 468 00:45:54,470 --> 00:45:58,380 You might say, well, hold on. I mean, there's a painting in here. 469 00:45:58,400 --> 00:46:05,180 Surely the symmetries of the Pentagon. I just see that that's a kind of symmetry, which is a smaller hiding inside. 470 00:46:05,810 --> 00:46:10,880 But if I tried to divide by the Pentagon and trying to symmetrical objects, it doesn't make any sense. 471 00:46:10,910 --> 00:46:17,060 Turns out the mathematics that go on to balance that there's no way to break this down into smaller objects. 472 00:46:17,210 --> 00:46:23,060 This turns out to be one of the first kind of interesting atoms in the periodic table of symmetry. 473 00:46:23,390 --> 00:46:29,540 Now, it's got a lot of studies on this one, but for 150 years, it's got a long way to go. 474 00:46:29,840 --> 00:46:35,870 We were trying to classify more and more these natural objects, trying to find the acids which make up symmetry. 475 00:46:36,020 --> 00:46:45,169 And it culminated in the 1980s with what we believe was the completion of operating a table of US extraordinary objects, 476 00:46:45,170 --> 00:46:56,060 including this amazing object, which is a and I'll show it to you because it's an object is a symmetrical object, which is a 996,893 dimensional size. 477 00:46:56,690 --> 00:47:02,530 Even in that sense, you can call it altered for you physically, but amazingly, isn't it? 478 00:47:02,930 --> 00:47:09,530 If you want to think about is this kind of weird movement which exists in an unusual size and symmetries. 479 00:47:10,010 --> 00:47:13,339 So the more symmetries that they are acting as the sun gets, 480 00:47:13,340 --> 00:47:21,260 we have to suppose we couldn't write this object and just lose interest and we just didn't have any pauses, 481 00:47:21,260 --> 00:47:25,010 just weird objects that suddenly appeared at this point in space. 482 00:47:26,780 --> 00:47:34,690 But how does the mathematicians say that's what I mean by 196,883 objects? 483 00:47:34,700 --> 00:47:38,270 I mean, how do mathematicians play around with objects and stuff point on it? 484 00:47:39,470 --> 00:47:45,380 Well, I think this is another example of how fantastic language is in mathematics and language. 485 00:47:45,590 --> 00:47:50,400 In a way, you have got lost the physical world symmetry of algebra. 486 00:47:50,780 --> 00:47:58,929 Suddenly the pictures disappear. I have access to the table which allows us to sort of see mathematically shapes. 487 00:47:58,930 --> 00:48:05,600 And I mentioned school and school of easy geometry, Cartesian geometry space to be a wonderful dictionary, 488 00:48:05,810 --> 00:48:10,040 a language which translates a lot of shapes into the world of numbers. 489 00:48:10,730 --> 00:48:20,450 So, for example, if I wants to describe a square in numbers, I can locate a school in a sort of east, west, North-South south location. 490 00:48:21,410 --> 00:48:34,489 So the square consists of a point at the origin 001 set along the horizontal axis, 101701 and that is it. 491 00:48:34,490 --> 00:48:39,950 One line where I find something that. So in a way I can translate a square into the. 492 00:48:40,590 --> 00:48:44,970 Seeing results pairs among school passengers identify for you this way. 493 00:48:45,930 --> 00:48:53,660 If I want to go off the Dimension Cube where I can draw you key, but I can similarly use the dictionary to translate it into numbers of Americans. 494 00:48:53,910 --> 00:48:59,550 AIDS triples in numbers. Which car? As long as you know how many moves you make in each direction. 495 00:48:59,790 --> 00:49:03,719 No, no, no. One, nought, nought, nought, nought, nought, one. 496 00:49:03,720 --> 00:49:08,160 All the way through to the stream point while online. Okay. 497 00:49:08,280 --> 00:49:09,750 What about a four dimensional cube? 498 00:49:10,170 --> 00:49:17,630 Now, the point is, this dictionary is wonderfully powerful, because although the visual side runs out of the three, I don't show you all of it. 499 00:49:18,300 --> 00:49:21,510 Still, the numerical by the numbers carries on. 500 00:49:21,540 --> 00:49:32,690 I can tell you in numbers, one four dimensional cube is it's a it's a shape which has points light occasions 0000. 501 00:49:33,150 --> 00:49:43,230 And then from that point, you got an extra now two points at 1000010000100001. 502 00:49:43,470 --> 00:49:50,520 So for edges that I just keep on going. Maybe six in each of these directions it's going at some point at one, one, one, one. 503 00:49:51,280 --> 00:49:54,900 Now, how many corners has a four dimensional cubicles? 504 00:49:56,010 --> 00:50:01,650 16 central. You able to work out how many different ways there are putting zeros and ones inside? 505 00:50:02,040 --> 00:50:06,240 16. You could also use the same trick to look at how many edges there are. 506 00:50:07,110 --> 00:50:13,800 Now you might have to explore very quickly using this language the geometry of a shape you cannot see. 507 00:50:15,070 --> 00:50:18,480 And little thought should be able to get around the edges that are all there. 508 00:50:18,780 --> 00:50:26,250 And that's the amazing thing that we can all see. Move to symmetries of this automation cube by using the same coordinates. 509 00:50:26,590 --> 00:50:29,890 So now I kind of have to show you a shadow of this shape. 510 00:50:29,910 --> 00:50:34,920 So, in fact, if you go back to Paris, there is a shadow of a four dimensional cube. 511 00:50:35,310 --> 00:50:39,090 Actually, the financial area in Paris. 512 00:50:39,510 --> 00:50:42,749 The all points is a shadow of information. 513 00:50:42,750 --> 00:50:46,980 Q In three dimensions. Do you think about a three dimensional cube? 514 00:50:47,280 --> 00:50:51,660 Actually, then all this is really three dimensional cube on a two dimensional capitals. 515 00:50:51,810 --> 00:50:57,389 What they do is make a square and they put a smaller square inside and then they don't see what it says. 516 00:50:57,390 --> 00:51:01,350 Because you think the same cube, because it's just a black thing. 517 00:51:01,690 --> 00:51:06,130 This is the same sort of concept a project organising cube has in three dimensions. 518 00:51:06,160 --> 00:51:10,590 What you get is a small view inside an object view and the size will join up. 519 00:51:10,960 --> 00:51:18,150 So I have an example here. Here's a four dimensional cube projected down into a three dimensional universe. 520 00:51:18,490 --> 00:51:24,060 I can see you correctly articulated that there are 16 corners and you can see them 521 00:51:24,240 --> 00:51:28,890 nice little whites balls and actually you'll be able to count all the edges. 522 00:51:29,190 --> 00:51:32,730 Now. So yeah, I do the maths. 523 00:51:33,120 --> 00:51:37,080 So the 12 inch cube on there. 524 00:51:37,470 --> 00:51:42,420 So that's 24, 26, 31, 32, 32 edges. 525 00:51:42,600 --> 00:51:48,010 But actually, you could have done that. Now, this picture, if I tried, was if I want an edge in terms of these. 526 00:51:49,350 --> 00:51:53,820 But it's going to be around 196,883 are actually shadows. 527 00:51:54,240 --> 00:51:57,790 And what's good for you. So I'm trying to make small symmetries of this shape. 528 00:51:57,810 --> 00:52:06,450 You really do have to use a mathematical language which translates geometry into numbers, and amazingly, you navigate out of it. 529 00:52:06,630 --> 00:52:13,560 Even measure is pretty an amazing pleased to be able to explore the symmetries and all of this number branches. 530 00:52:13,830 --> 00:52:17,219 And one of the most is of the will of symmetry. 531 00:52:17,220 --> 00:52:27,750 You have to complete this kind of classification over the centuries to incorporate the masses of all symmetry. 532 00:52:27,900 --> 00:52:33,060 In fact, when I finished my degree area in offices, I mean, I've fallen in love with world symmetry. 533 00:52:33,240 --> 00:52:40,470 It was now 1985, and I just heard about this sort of completion of this project. 534 00:52:41,250 --> 00:52:50,340 The Cambridge seemed to be the place to go to study symmetry, and in fact, they produced this amazing piece that has been around is the real thing. 535 00:52:50,940 --> 00:52:57,180 The Atlas five is this basically inside here are all the building blocks. 536 00:52:57,660 --> 00:53:04,270 This is the periodic table of symmetry was produced in about 1985, just when I was finishing my three. 537 00:53:04,310 --> 00:53:12,120 And I went up to Cambridge because John Conway and his group to try and find out, you know, what are the next steps after having done this. 538 00:53:13,290 --> 00:53:14,820 So I was very keen to join that group. 539 00:53:16,470 --> 00:53:25,440 And he sat down and he said, well, you know, we are all very obsessed with symmetry, so let's make out at the same time. 540 00:53:25,830 --> 00:53:39,879 He said, Oh. We have to drop the do something against Rangers, though, because I know the authors in this area have six letters on each word. 541 00:53:39,880 --> 00:53:47,530 I don't like two schools in the same place when I say, you know why, but nobody's going to do that. 542 00:53:48,040 --> 00:53:52,990 I was like going agree. So as bad as it is to and others. 543 00:53:53,680 --> 00:53:58,080 Yeah. And if you drop one of those letters. 544 00:53:58,520 --> 00:54:04,809 Walter, we only have two games on the air, so I'm not an MP. 545 00:54:04,810 --> 00:54:11,379 So my argument is, if that's not all, that's the first to join the group with John Conway. 546 00:54:11,380 --> 00:54:17,620 And then he got his Ph.D. student, Ralf Hedges, that it was this guy hanging around and Cambridge just kept running around. 547 00:54:17,850 --> 00:54:23,559 It seemed to be quite helpful. Simon Norton So he was the third all go joined. 548 00:54:23,560 --> 00:54:27,940 He was really good at computing. The things he wore them all through joined with Wilson. 549 00:54:28,450 --> 00:54:34,999 They all joined in alphabetical order. So if I was going to join the group, I was going to have to change my name off. 550 00:54:35,000 --> 00:54:44,760 The same for but since. So now about that point I realise well I know that's going a little bit too far though, 551 00:54:45,940 --> 00:54:53,999 and so I'm a little bit concerned that I came back to work since I wanted to start my research into the world of surgery. 552 00:54:54,000 --> 00:54:57,320 And I, I want to go maybe. Maybe surgery finished. 553 00:54:57,420 --> 00:55:03,420 Maybe we all understand everything there is to know about, but that turns out not to be true is never true. 554 00:55:04,140 --> 00:55:10,290 So one problem that opens up so many more interesting columns in particular, particularly single who monster. 555 00:55:10,670 --> 00:55:16,090 It was this strange thing, right? In 196,883 inches right. 556 00:55:16,170 --> 00:55:22,560 Here is why you suddenly suddenly emerge in this financial space and it has this number or any significance, 557 00:55:23,190 --> 00:55:28,740 but it turns out it does this number you find in a completely different area of mathematics called number theory. 558 00:55:28,980 --> 00:55:33,790 This number comes up in some modular forms, which is very much related to the work, 559 00:55:33,790 --> 00:55:40,470 what I wanted on Fermat's Last Theorem and even conflate the other dimensions with somebody, this monster appears. 560 00:55:40,710 --> 00:55:46,110 All the numbers of the dimensions have something to do with this completely different area of mathematics. 561 00:55:46,890 --> 00:55:51,750 And so one of the challenges has been we made some progress, but I still think there's a lot to unlock. 562 00:55:51,930 --> 00:55:57,749 Why has this strange metrological anything to do with the world of number theory in school? 563 00:55:57,750 --> 00:56:05,610 Monstrous moonshine. Because John Connolly thinks that there's somehow a third object which is shining lights on both of these things, 564 00:56:05,610 --> 00:56:09,300 which in the moonlight we see is these strange numbers appearing. 565 00:56:09,690 --> 00:56:17,370 In fact, Richard Fortune's Won the Fields Medal or Nobel Prize for making a lot of discoveries about what? 566 00:56:17,370 --> 00:56:20,729 That the sun might be shining a light on a clump. 567 00:56:20,730 --> 00:56:28,590 I still believe that there's a lot we still do not understand about this strange symmetrical object, which is sort of one of the strange things. 568 00:56:28,690 --> 00:56:35,790 This happens on my symptoms, but actually my own research I might be interested in. 569 00:56:36,120 --> 00:56:40,470 If this is the periodic table, then what are the molecules of symmetry that you can make? 570 00:56:40,650 --> 00:56:45,300 What can you build? What are the new sort of trees that you can make out of this list in the spirit table? 571 00:56:45,330 --> 00:56:50,280 So as you you know, I spend more time here analysis and doing research and symmetry, 572 00:56:50,280 --> 00:56:57,120 trying to build new symmetry out of the the building blocks that we got a in the act as a simple so and 573 00:56:57,120 --> 00:57:02,249 so I discovered a strange using that for objects with connections to things called related curves. 574 00:57:02,250 --> 00:57:08,400 And in fact I got one of these Newsmax.com objects which hasn't got a name yet, 575 00:57:08,430 --> 00:57:12,780 and this is going to be a price for you that I'm going to name the symmetrical object. 576 00:57:12,780 --> 00:57:19,140 Also the person who can work out how many symmetries that Rubik's Cube has. 577 00:57:19,440 --> 00:57:25,979 So I got a little certificate here. It's not a name yet, so that is something. 578 00:57:25,980 --> 00:57:30,010 Group. This could be your name. No, no. Modern science. 579 00:57:30,610 --> 00:57:35,669 Science is a kind of a process of evolution as that one theory gets overturned by another. 580 00:57:35,670 --> 00:57:41,760 You know, the science the ancient Greeks proved in law school of business. 581 00:57:42,090 --> 00:57:48,810 The amazing thing about mathematics is it's eternal. This group will be there forever and species will die. 582 00:57:48,840 --> 00:57:54,410 Stars will up. But this group may give you a little bit of immortality if you can claim some. 583 00:57:54,780 --> 00:57:58,320 So the challenge is, okay, how many symmetries does this Rubik's Cube have? 584 00:57:59,380 --> 00:58:03,780 Okay, so I've put it back there, the Rubik's Cube here now. 585 00:58:03,780 --> 00:58:05,990 So how does I'm going to do this? Okay. 586 00:58:06,240 --> 00:58:17,010 What I want you to do is if you go to my guess, I just want you to make a guess at how many digits this number has. 587 00:58:18,090 --> 00:58:27,389 So. So just if you count I did a number of women make a guess how many digits do you also think it's got? 588 00:58:27,390 --> 00:58:32,430 A hundred symmetry. So it's got three digits. Okay, now you want to play you please stand up. 589 00:58:32,760 --> 00:58:39,180 I'm going to try and sort it out. So make your estimates using all three symmetries or three in our series. 590 00:58:39,270 --> 00:58:45,390 Right. So we've got some sort of players or we need to guess and you will get to be able to see if you get close to the right. 591 00:58:45,840 --> 00:58:49,139 So you only have one estimate. I don't need a precise formula. 592 00:58:49,140 --> 00:58:52,470 I just want you to estimate how many digits you think there are. 593 00:58:52,950 --> 00:58:58,380 Okay, so I'm going to sort it out. I'm used to calculating the but very impressive. 594 00:58:59,670 --> 00:59:06,180 So if you go to ten or fewer digits, I want you to sit down. 595 00:59:06,420 --> 00:59:11,950 Underestimated the number. So more than that. 596 00:59:12,120 --> 00:59:20,940 So if you now if you got 30 or more digits, you also sit down because you overestimate. 597 00:59:21,240 --> 00:59:25,290 And so it's the numbers. It's between ten and 30. 598 00:59:26,070 --> 00:59:32,940 Okay. So if you've got some, uh, more than 20 digits in your number. 599 00:59:34,110 --> 00:59:38,060 I want you to keep standing. All right. 600 00:59:38,430 --> 00:59:41,880 So it's between. Right. So you go there. Sometimes you got to sit down. 601 00:59:42,160 --> 00:59:50,130 So. Okay. If you've got more than 28 tickets and you have a you want to sit down. 602 00:59:52,040 --> 00:59:55,630 27. 23. 603 00:59:55,670 --> 00:59:59,850 Sit down. Okay. Right. Right. 604 00:59:59,900 --> 01:00:02,900 So it's between. It's a it's more than 23. Okay. 605 01:00:03,160 --> 01:00:06,959 It's alright. So how many of you. Tony. 606 01:00:06,960 --> 01:00:10,870 So you got to sit down to sit down. 24. 607 01:00:11,780 --> 01:00:15,349 24, 24, 25, 25. 608 01:00:15,350 --> 01:00:19,310 This is great news. So what is your name, sir? 609 01:00:19,520 --> 01:00:23,060 It's actually has 26 inches 25. Exactly. 610 01:00:23,300 --> 01:00:26,690 That's amazing. So I have work here. No, no. 611 01:00:26,780 --> 01:00:30,059 Okay. What's your name, sir? Of course. Yes. See you. 612 01:00:30,060 --> 01:00:33,350 Won't see you. Can you, auntie? Do you want to say I think. Bruce. 613 01:00:34,310 --> 01:00:39,250 Which Hamilton? Hamilton. Paul Hamilton. Okay. 614 01:00:39,250 --> 01:00:45,990 That's cheating because he's a very famous scientist. You go out to the White House, so so let me do this. 615 01:00:46,000 --> 01:00:51,900 Okay, so k you all t. So the Kurt Hamilton group has just been born. 616 01:00:53,260 --> 01:01:00,010 It's a new symmetrical object built out of the symmetries in the periodic table curtain, so we can come collect this afterwards. 617 01:01:00,490 --> 01:01:05,920 So there are in fact, it's a novel with 25 different surfaces. 618 01:01:05,920 --> 01:01:10,719 Occasionally, it's not one of the atomic symmetries. You can break down two centuries and smaller objects, 619 01:01:10,720 --> 01:01:18,970 but it's amazing that number of metal moves you can do that object which make it sort look like a cube, which is genuinely, distinctly different. 620 01:01:19,300 --> 01:01:27,410 Interestingly, the company that manufactures this Rubik's Cube, the ideal toy company say did all the packaging, the original Rubik's Cubes. 621 01:01:27,430 --> 01:01:32,589 There are more than 3 billion possible states that you can go down now. 622 01:01:32,590 --> 01:01:38,860 Such an underestimate is analogous to McDonald's proudly announcing that they sold more than 120 hamburgers. 623 01:01:39,070 --> 01:01:44,950 So it is obvious that large numbers have now, as you have discovered, many more of these symmetrical objects. 624 01:01:44,950 --> 01:01:51,519 And so you feel that it's a myth that Kurt Hamilton has beaten you to get a bit of immortality. 625 01:01:51,520 --> 01:01:58,179 Actually, we have a project here out of my Muscle Institute where it's for donation to charity that I support. 626 01:01:58,180 --> 01:02:03,340 And in Guatemala, an educational charity which gets kids off the streets and into education. 627 01:02:04,000 --> 01:02:09,159 I will name a smart girl. I'll take one of these new objects that I discovered off. 628 01:02:09,160 --> 01:02:12,730 You are a for a not why you calling but a present for somebody. 629 01:02:13,930 --> 01:02:17,409 Then they're going to own all the money goes to the charity. 630 01:02:17,410 --> 01:02:28,649 But more than just writing a. You know, it was interesting that, you know, we make a lot of progress in my money. 631 01:02:28,650 --> 01:02:30,809 So there's still all of these problems. 632 01:02:30,810 --> 01:02:38,129 And, you know, I think for me, it is those things that, you know, we still don't know, always putting these symmetries together. 633 01:02:38,130 --> 01:02:45,000 We still don't really understand what it is we all get. The monster is in there 196,883 dimensions. 634 01:02:45,000 --> 01:02:52,469 And but for me, that's that's what makes me want to carry on doing mathematics you know broke out killed at the age of 20. 635 01:02:52,470 --> 01:03:03,240 I'm not going to make it off at first, but I often come back to that wonderful quote this Professor Kurokawa told me about a Nico, 636 01:03:04,020 --> 01:03:09,240 which I think sums up mathematics as well as art. You know, in everything, uniformity is undesirable. 637 01:03:09,510 --> 01:03:14,219 There is something interesting and gives. One is the feeling that there is room for growth. 638 01:03:14,220 --> 01:03:18,540 And he says kind of silly on social things which keep us going here. 639 01:03:19,140 --> 01:03:46,879 Study mathematics, I think. So there's an opportunity to ask some questions about symmetry or any other mathematical problems. 640 01:03:46,880 --> 01:03:50,170 You only go on the line what might see. 641 01:03:50,170 --> 01:03:55,640 And so yes. Question in back here we're going to like on the assignments to. 642 01:04:07,670 --> 01:04:11,460 We're saying. All right. We're going to come back to you. 643 01:04:11,790 --> 01:04:17,730 We are going to sit right with that right high. 644 01:04:17,940 --> 01:04:21,750 Is it significant? A maximum number of images there are is a prime number. 645 01:04:24,370 --> 01:04:28,209 Oh, you mean for the Alhambra? Yeah. For example. 646 01:04:28,210 --> 01:04:35,680 Yes. So we were looking at the walls of the Alhambra as as a two dimensional shapes, how they put together. 647 01:04:35,800 --> 01:04:39,940 Interesting that it's 17, which is the final. Yeah, it's a very good question. 648 01:04:39,940 --> 01:04:47,940 If that's the sort of thing that we need to be a mathematician, is that in this case, I think it's not significant actually. 649 01:04:47,950 --> 01:04:51,500 You know, it's my favourite number 17. I mean, I'm obsessed with it. 650 01:04:51,540 --> 01:04:57,310 It's number eight for my football team. And there's the cicadas have a 17 year life cycle. 651 01:04:57,520 --> 01:05:06,820 But actually, I think in this case, actually, 17 is more of a military solution so that you find in the number of ways that you can do things. 652 01:05:06,830 --> 01:05:15,879 It just turns out that 17 is the way because for example, if you go, you can consider sort of Alhambra in higher dimensions as well. 653 01:05:15,880 --> 01:05:24,340 So for example, the number of crystals that are possible is essentially the same question as the crystal structures, 654 01:05:24,340 --> 01:05:27,879 and that isn't so that's the way it has a you know, 655 01:05:27,880 --> 01:05:35,340 it's a good question to ask, but an anxiety, what am I going to prove is it should be climb if I go back and it turns out not to be right. 656 01:05:35,360 --> 01:05:38,500 So it's more trees. 657 01:05:39,550 --> 01:05:45,940 But I see you know that's what arises in mathematicians is asking those looking for those kind of coincidences. 658 01:05:45,940 --> 01:05:50,320 I take the most the most 196,883. 659 01:05:50,620 --> 01:05:53,830 That's the number. And they're saying we got the same number somewhere else. 660 01:05:53,890 --> 01:05:58,510 And I could have just been a coincidence, but when we started to see more numbers appearing, 661 01:05:58,660 --> 01:06:04,690 the next time you see the monster is also hiding inside the ceiling number, there is an explanation. 662 01:06:04,960 --> 01:06:10,330 Then you thought, okay, I'm onto something now. So good question, but that's it. 663 01:06:10,330 --> 01:06:13,500 But after a while we see actually doesn't seem to be significant is. 664 01:06:16,560 --> 01:06:23,760 Who questions is it? We had a question in the middle here and we could get the mike to the guy in the middle, in the blue shirt. 665 01:06:23,760 --> 01:06:27,000 But I'll take this on first. So you just come down with it? 666 01:06:27,240 --> 01:06:32,850 Yes. So you spend a lot of time explaining science and mathematics to people and sharing that knowledge. 667 01:06:33,630 --> 01:06:34,670 Two little questions. 668 01:06:34,860 --> 01:06:41,790 Firstly, there know a push, it seems when we're funded by the public at doing research and that sort of thing, that what we do is useful. 669 01:06:43,290 --> 01:06:48,360 How do you what are your favourite arguments for maintaining mathematical research? 670 01:06:48,930 --> 01:06:51,960 I guess from the very purist level, right through all the scales. 671 01:06:52,170 --> 01:06:59,700 And also, do you think as publicly funded research as should we be doing more of what you're doing, 672 01:06:59,700 --> 01:07:06,000 which is explaining what we do to people and helping them to explain or understand mathematics and its beauty? 673 01:07:06,360 --> 01:07:10,260 Yeah, well, as to the question, I think it's. 674 01:07:12,930 --> 01:07:19,649 We're in a kind of rocky situation with mathematics that very often the research that we do with most mathematicians, 675 01:07:19,650 --> 01:07:26,520 I don't think do mathematics because of utility. We don't do that because we want to create a new piece of technology. 676 01:07:26,700 --> 01:07:31,380 We do mathematics because we feel like we're getting access to internal trees that nature is. 677 01:07:32,130 --> 01:07:36,720 I think aesthetics drives a lot of the directions that we choose in mathematics. 678 01:07:36,720 --> 01:07:44,090 So there's very much more similarity between the arts or very often know the choices that we make in science, 679 01:07:44,120 --> 01:07:48,120 very often driven by trying to explain the physical world around, you know, 680 01:07:48,480 --> 01:07:55,049 these symmetries on discovering things like to see them or why not studying them. 681 01:07:55,050 --> 01:08:03,150 Because I think how we use the stories that I can tell, we are all magical and full of surprises and excite me. 682 01:08:03,150 --> 01:08:08,310 And that's and a sense of your second question, which is why why do I do this? 683 01:08:08,760 --> 01:08:16,800 I do this partly because I want the next generation of mathematicians to and I want to excite them. 684 01:08:16,920 --> 01:08:25,049 My I'm paying back my teachers to Alison. He took me out of the class in the middle of a lesson and got me excited about mathematics. 685 01:08:25,050 --> 01:08:28,500 And I sort of want to pay my little way for saying, okay, 686 01:08:28,760 --> 01:08:35,800 I want to tell people as well so they can get excited and become mathematicians as well as she's selfish. 687 01:08:36,510 --> 01:08:42,340 The reason I do this because I love my subject so much, I love talking about it and then communicate, communicating. 688 01:08:42,840 --> 01:08:47,440 And for me, I really when I make a mathematical discovery, there are two things about being in a position. 689 01:08:47,490 --> 01:08:52,990 One is making a new discovery, but the second is communicating it, and that's when it starts to come online. 690 01:08:53,010 --> 01:08:58,020 When I tell you about something I've done or I'm in a seminar here in the department, 691 01:08:58,050 --> 01:09:01,290 or I write a paper and I send it to a journal and somebody else reads it. 692 01:09:01,530 --> 01:09:04,950 That's the moment when suddenly the thing has life and it begins to breathe. 693 01:09:04,950 --> 01:09:11,630 And and so I think that's, you know, we all do this in some sort of level. 694 01:09:11,640 --> 01:09:16,830 And the more we communicate, the more that subject lives and breathes. 695 01:09:17,670 --> 01:09:19,409 But I think we all have these opportunities, 696 01:09:19,410 --> 01:09:25,650 although a lot of these symmetrical objects we discovered purely for the excitement of discovering something new, 697 01:09:26,010 --> 01:09:31,229 actually, we can very quickly connect it with a utility. 698 01:09:31,230 --> 01:09:34,800 And the fact that this can create new technology, 699 01:09:35,640 --> 01:09:43,290 for example in the is the Acme supply and I simple said was an object is just discovered in use imagery which actually 700 01:09:43,290 --> 01:09:52,259 that became the basis of a new Eric Watson code that was used by Voyager to take pictures of Saturn and these pictures, 701 01:09:52,260 --> 01:09:54,420 right. Corrupted when they were delivered back to Earth. 702 01:09:54,630 --> 01:10:01,230 But using the symmetry of this code, they were able to correct these errors and produce some crystal clear images. 703 01:10:01,860 --> 01:10:07,950 That is a lot like if I give an article and experience in the future, but this is my error in one corner. 704 01:10:08,160 --> 01:10:11,890 Rushing Roshi know how to correct error because of the symmetry and the rest of the target. 705 01:10:12,270 --> 01:10:20,249 So symmetry actually is at the heart of many of the photos which encode a picture or a voice in the digital data, 706 01:10:20,250 --> 01:10:22,590 which tend to get to be corrupted in on the way back. 707 01:10:23,370 --> 01:10:33,350 So I think we can very easily justify why nobody discovered that symmetry because they wanted to create the perfect prime numbers. 708 01:10:33,360 --> 01:10:40,679 I used the Internet cryptography, but the things we discovered by our numbers that I use were discovered by Fama and Weiner. 709 01:10:40,680 --> 01:10:46,649 They to know about the Internet. But I think it's a balance. 710 01:10:46,650 --> 01:10:52,710 And, you know, I recognise that governments have limited resources, but you must always have a balance for value. 711 01:10:53,520 --> 01:10:59,130 And so yes, sure, there are some things which we can see have short term goals and there's always other. 712 01:10:59,150 --> 01:11:03,510 But there are many things that's that's look at this. 713 01:11:03,510 --> 01:11:07,920 I will have another thing that might be useful very much later. 714 01:11:08,010 --> 01:11:13,440 Turned out to be just the thing you need to do to to Google, for example. 715 01:11:13,440 --> 01:11:19,110 Google isn't like Google elves just sitting there looking at the websites that you've just asked about. 716 01:11:19,320 --> 01:11:26,160 It's a clever bit of mathematics, eigenvalues of matrices, which helps you to set up exactly what you're looking for. 717 01:11:26,820 --> 01:11:38,430 So it's, I think, through the way that we should justify why still resources research our brains about symmetry should be funded, 718 01:11:38,430 --> 01:11:40,290 even though we may not know where it's going to end. 719 01:11:40,290 --> 01:11:48,200 Is that huge number of examples of mathematical research that has been done which which has been subsequently catalysed. 720 01:11:48,480 --> 01:11:56,760 But I think we shouldn't miss the fact that actually still worth as a as a culture, you know, why should we come to music? 721 01:11:57,120 --> 01:12:04,590 You know, we we are for our society. If we don't have these different strands, each one helps the other. 722 01:12:04,680 --> 01:12:09,030 I think, you know, I spend a lot of time talking with artists. 723 01:12:10,230 --> 01:12:14,310 I'm doing a project of the moments with the theatre company. The House mathematics. 724 01:12:14,600 --> 01:12:19,650 Actually, that helps me because they make you look at a question in a completely different way and have a different way of looking at things. 725 01:12:19,830 --> 01:12:23,730 And that's, you know, I really enjoy it because creating a piece of paper about maths. 726 01:12:23,880 --> 01:12:27,930 But actually it's, I think it benefits all of these things enriching each other. 727 01:12:27,930 --> 01:12:31,270 And if you count one else, you are going to have a much poorer society. 728 01:12:33,600 --> 01:12:35,730 And so the question here. 729 01:12:38,490 --> 01:12:47,640 I probably some of the other people noticed as they came into this building outside one of the doors there's that creating a tiled surface. 730 01:12:47,790 --> 01:12:50,790 Penrose tiles based on an Oxford discovery. 731 01:12:51,210 --> 01:12:57,780 And they're marked with lines, curving lines. And some of those lines make a neat circle, about six feet in diameter. 732 01:12:58,290 --> 01:13:03,090 But while I was waiting to come in, I tried following the lines like a labyrinth. 733 01:13:03,780 --> 01:13:07,470 Some of the more complex patterns, like the outline of a five bedroom floor. 734 01:13:08,160 --> 01:13:10,350 But one line went on and on and on. 735 01:13:10,560 --> 01:13:18,810 And I was wondering, is that potentially an infinite line in that part of the layout of the tiles isn't complete yet, 736 01:13:18,810 --> 01:13:22,080 but I'm afraid it's going to be fine. It's not like that. 737 01:13:22,300 --> 01:13:31,290 Well, this is the beautiful thing about that design, is that it's increasing its symmetry, 738 01:13:31,290 --> 01:13:38,490 like five pointed star or something, but it has no repeating symmetry at all. 739 01:13:38,520 --> 01:13:46,760 So now I'm I would have to do a little bit of research to see whether there is an infinite line inside there. 740 01:13:46,770 --> 01:13:50,250 But I'm absolutely sure that there will be an unbounded. 741 01:13:50,310 --> 01:13:58,140 So the even if they're will find it will definitely be an unbounded number, I suspect, and I won't. 742 01:13:58,500 --> 01:14:04,050 But the interesting, interesting question and, you know, if given this answer and with all their actual policies parsing, 743 01:14:04,500 --> 01:14:11,250 which must be infinite and what what you discovered with this tiny is a very interesting time because in some sense it 744 01:14:12,060 --> 01:14:19,260 contradicts what I said about the Alhambra because it looks like an 18 mean you taught it but it doesn't have the symmetry. 745 01:14:19,260 --> 01:14:25,169 It has no move you can make inside those tiles such that if you move in some way, 746 01:14:25,170 --> 01:14:31,290 they would sit back on top of each other because of what is known periodicity to it so dramatically. 747 01:14:31,290 --> 01:14:35,010 They're objects that have symmetry that by force, symmetry or other symmetries, 748 01:14:35,220 --> 01:14:42,840 you were able to prove the global act on water treaties that nature actually discovered these before Roger. 749 01:14:43,560 --> 01:14:54,660 Roger actually famously and his family discovered this pattern of been used on some toilet paper. 750 01:14:54,670 --> 01:14:59,190 And this is very useful for toilet paper because because of the Non-repeating passage, 751 01:14:59,190 --> 01:15:02,820 you don't get the kind of build up if you wrap your mind around, around. 752 01:15:02,850 --> 01:15:06,060 So you have some experience, you can get a nasty sort of build. 753 01:15:06,210 --> 01:15:11,500 So this company had used it had actually cleverly patented the design. 754 01:15:11,520 --> 01:15:18,090 And I think they settled out of court for some time. 755 01:15:18,690 --> 01:15:23,940 But actually it's be discovered before Roger because we found crystals, quality crystals. 756 01:15:24,390 --> 01:15:29,970 One of the recent Nobel Prizes in chemistry was for the investigation of these crystals, 757 01:15:30,300 --> 01:15:36,180 which is quite remarkable because it is when you start to make the tiles. 758 01:15:36,180 --> 01:15:36,389 I mean, 759 01:15:36,390 --> 01:15:45,709 they have been very careful outside because there's you sort of have to have global knowledge for the whole structure to be able to lay it down. 760 01:15:45,710 --> 01:15:48,090 And so when a crystal is forming these quasicrystals, 761 01:15:48,750 --> 01:15:57,750 it's quite an interesting question about how does out how does this kind of crystal known global properties, although it's to down as it grows. 762 01:15:58,760 --> 01:16:07,480 So there are a lot of interesting questions around the this norm here only can I say around including on the US. 763 01:16:18,320 --> 01:16:26,750 Do you believe mathematics is discovered and created? And because I know Girdle said that axiom to something we believe which is true, 764 01:16:26,750 --> 01:16:32,150 but nowadays people call things which are axioms, which we don't necessarily know whether they're true or not. 765 01:16:32,450 --> 01:16:36,190 I do believe the truth lies in mathematics all the time. 766 01:16:36,200 --> 01:16:43,670 Or maybe the hypothesis is that we haven't breathed, which I actually don't have any proof, like the continuum hypothesis. 767 01:16:43,830 --> 01:16:45,350 Yeah, well, 768 01:16:45,350 --> 01:16:54,710 I think that it's it's a kind of eternal tension which exists in a mathematician's life about these two words about discovery and creation. 769 01:16:56,510 --> 01:17:00,380 And I find myself using both of them at different times. 770 01:17:00,650 --> 01:17:05,629 For example, there is new symmetrical objects now. 771 01:17:05,630 --> 01:17:12,900 I felt I created that. I felt that it was an act of creation to somehow piece together these new set of 772 01:17:12,920 --> 01:17:18,350 ideas to create this shape which has lovely connections and with electric cars. 773 01:17:18,890 --> 01:17:27,200 And there was a time I had this feeling of clashing that was all that was there all along, somewhat easier to put together and discover. 774 01:17:28,100 --> 01:17:30,280 So then you start to it like discovery. 775 01:17:30,290 --> 01:17:39,619 And I don't think there is this continual tension about how much and you see this in a lot of mathematical discoveries gets discovered. 776 01:17:39,620 --> 01:17:44,480 At the same time, non-Euclidean geometry was discovered by three different people. 777 01:17:44,720 --> 01:17:50,360 So it's a field like it was it was a continent out there for mathematicians to discover. 778 01:17:50,360 --> 01:17:56,630 And it was Gauss Mollaei who who both came close together. 779 01:17:58,040 --> 01:18:02,959 And, you know, you want to say that about and I did The Magic Flute by Mozart. 780 01:18:02,960 --> 01:18:06,080 You wouldn't think that anybody else could create the Magic Flute. 781 01:18:06,370 --> 01:18:16,699 It really isn't that isn't a discovery. But actually, if you talk to a lot of composers, you find them actually countering that and saying, 782 01:18:16,700 --> 01:18:24,439 well, you'd be surprised how often actually a new musical idea actually has been zeitgeisty. 783 01:18:24,440 --> 01:18:28,820 And people come across the same musical idea almost simultaneously. 784 01:18:29,960 --> 01:18:34,970 They would write the same piece of music. But then even in mathematics, we ratti we might have similar ideas. 785 01:18:34,970 --> 01:18:37,790 We rarely write exactly the same mathematics. 786 01:18:38,340 --> 01:18:45,560 And so I think actually even in the arts, one can see a little bit more of a tension between this creativity and discovery. 787 01:18:45,920 --> 01:18:46,700 There's interesting story. 788 01:18:46,700 --> 01:18:56,510 I was at a festival with Michael Nyman and I asked him a question during the session about whether what did he think as a composer, 789 01:18:56,690 --> 01:19:01,160 whether he thought music was just created, or was there an element of. 790 01:19:01,490 --> 01:19:05,990 Do you feel like you ever discovered music? And he said, Well, yes, I can give you an example of this. 791 01:19:06,740 --> 01:19:14,360 And he said, I found this amazing sequence, of course, where you can get a soprano to just hold a note all the way through. 792 01:19:14,360 --> 01:19:20,470 The chords just changed around her, but she just kept this one note and it was a very beautiful sort of property. 793 01:19:20,480 --> 01:19:23,330 So the sequence, of course, and he was very proud of it. 794 01:19:23,780 --> 01:19:29,750 And then a few years later, he bought an album by the Scissor Sisters, and it was an extra material. 795 01:19:29,890 --> 01:19:32,000 It was an encore from an article or something. 796 01:19:32,330 --> 01:19:38,600 And you listen to some of his material and he heard the same sequence, of course, what, running through one of the songs. 797 01:19:39,230 --> 01:19:44,330 And he said he couldn't believe that they'd found it independently. 798 01:19:44,360 --> 01:19:48,500 So yeah, she took them to court for ripping off his music. 799 01:19:49,190 --> 01:19:51,890 And so there was a whole debate within the court case, 800 01:19:52,040 --> 01:19:56,900 and they got musicologists to try and see whether the sequence of chords and ever be found before. 801 01:19:57,230 --> 01:20:03,830 And eventually Scissor Sisters had to settle and email that they actually had written off because there was no evidence that. 802 01:20:04,250 --> 01:20:13,760 Michael Nyman take that as an example. Actually, music, you can make discoveries of structures in a way that you think is just creative. 803 01:20:14,240 --> 01:20:20,840 Now coming to a question about Google is very interesting because that fact gave us a little bit of room for creativity, 804 01:20:21,110 --> 01:20:30,950 because you mentioned the continuum hypothesis. You know, we which I will actually come to in one of my other lectures later on. 805 01:20:31,700 --> 01:20:39,560 But actually it shows that we got this question about whether there's a set of numbers which is 806 01:20:39,710 --> 01:20:46,100 strictly bigger than the whole numbers and strictly smaller than the rational numbers of real numbers. 807 01:20:46,550 --> 01:20:50,770 And it turns out that we can make a choice. It's a bit like the answer is yes and no. 808 01:20:50,960 --> 01:20:53,510 I think it's what students would love in an exam. All right. 809 01:20:55,460 --> 01:21:02,840 So I think it's a very deep philosophical question you are answering, which I think we we constantly wrangle with in a way, 810 01:21:02,840 --> 01:21:06,560 how many stick our head in the round about because we just go on doing what we do. 811 01:21:10,510 --> 01:21:14,960 That's. You sound a. 812 01:21:31,190 --> 01:21:34,380 I'll try and talk loudly as it's coming through. Brilliant. 813 01:21:34,400 --> 01:21:38,710 Excellent. I love to see the pictures that have burned already. 814 01:21:38,720 --> 01:21:48,290 Scale of the Alhambra. And it seems absolutely incredible that they got all 17 symmetry elements in two days in the Alhambra. 815 01:21:49,100 --> 01:21:52,999 I've been that. I'm afraid I read as much about it as I would have liked to. 816 01:21:53,000 --> 01:21:58,200 But do you know? Well, so did the people who designed the Alhambra. 817 01:21:58,250 --> 01:22:03,620 Have they done a lot of I guess that they looked around in nature and kind of looked at the structures and nature? 818 01:22:03,620 --> 01:22:04,729 I mean, does it it can't. 819 01:22:04,730 --> 01:22:11,450 It doesn't it feels like it can't be a coincidence or is it something about the sort of symmetry elements are almost wired into us in some way, 820 01:22:11,450 --> 01:22:18,200 I guess is a slightly psychological question to put to you rather mathematical one, but I'm really interested to hear your thoughts on that. 821 01:22:19,660 --> 01:22:27,160 I think that's a that I think we all very hard line to be extremely sensitive to symmetry. 822 01:22:27,200 --> 01:22:32,440 I mean I think at that which is why we find it again and again, 823 01:22:32,560 --> 01:22:41,410 it's something we play with or withdraw and there's lots of evidence of the brain is be so addicted to symmetry, 824 01:22:41,410 --> 01:22:49,090 the desire to see symmetry where there isn't a relation to those inkblots, you know, 825 01:22:49,090 --> 01:22:57,100 there's able to there's a basically is just a passive which is the god symmetry symmetry around it and use those because. 826 01:22:58,920 --> 01:23:04,620 He knew that we would try and interpret. And if you're in a psychological session, you will try and tell a story. 827 01:23:04,860 --> 01:23:09,920 It is called symmetry. It's me telling you something. And so you started to unleash your inner mind. 828 01:23:09,960 --> 01:23:13,110 You know that it causes no. Got anything particularly special about it. 829 01:23:13,110 --> 01:23:23,060 But these different rules of images just seem to tease out of you as stories because you try and interpret it well. 830 01:23:23,100 --> 01:23:26,660 You used to get all his patients to draw mandibles, 831 01:23:26,880 --> 01:23:33,510 these symmetrical kind of Buddhist shapes because he believed in they would express their inner workings of their mind. 832 01:23:33,510 --> 01:23:36,180 So as soon as Freud said, I see blank, 833 01:23:36,180 --> 01:23:45,089 I believe in a lot of psychological problems based on the fact that we try to make logic symmetrical logic is very asymmetrical. 834 01:23:45,090 --> 01:23:51,600 If the if A and B, that's what he does not be repeating that you want to reverse these things. 835 01:23:52,470 --> 01:24:00,030 But actually the mindset is always to reverse the thing that actually that could be responsible for strange psychological disorders, 836 01:24:01,020 --> 01:24:10,670 for example, is was a patient of his. That's when when blood was being taken from the arm was that the arm was being removed from the bodies. 837 01:24:11,040 --> 01:24:19,620 And just to this reversal, and if you look at a lot of things that you can find the same sort of explanations that this sort of rape is going on. 838 01:24:19,630 --> 01:24:23,540 So I think going to the psychological side, I think that, you know, 839 01:24:23,590 --> 01:24:29,750 the brain is so online that sometimes it can confuse itself and, you know, hungers. 840 01:24:29,760 --> 01:24:37,110 I think because I think this is a good example. I think all of those images were things that they would have naturally seen around them. 841 01:24:37,200 --> 01:24:46,350 I think this is a great example of, first of all, being inspired by nature and a lot of the questions of science and the like is stalled in nature. 842 01:24:46,560 --> 01:24:55,080 But then we lose our imaginations, run riots, and and we start to try and push things which are beyond the natural world. 843 01:24:55,080 --> 01:24:58,950 And a lot of the mathematics, I think you can find its source in the natural world, 844 01:24:58,950 --> 01:25:03,420 but then it's about trying to find something and the other possibilities. 845 01:25:03,780 --> 01:25:11,219 So I would say that some of the Moorish artists who came up within the 14th century, those designs, 846 01:25:11,220 --> 01:25:18,840 and it's interesting that I showed you those patterns with the same symmetries, although they look very different. 847 01:25:19,440 --> 01:25:22,920 Interestingly, you find those in the same bit of the palace. 848 01:25:23,820 --> 01:25:29,070 So the entrance to the palace is full of lots of rotations of the floor. 849 01:25:29,110 --> 01:25:35,429 Two reflections and the second floor of the House is where I was and people visiting 850 01:25:35,430 --> 01:25:40,530 the palace would be hosting it and it's quite clients and you could see the symmetry, 851 01:25:40,530 --> 01:25:47,069 right. Some of the symmetries. Well the different patterns as you go through into the more intimate parts of the palace to the harem, 852 01:25:47,070 --> 01:25:53,910 for example, then you suddenly see reflections disappearing. You have triangles, hexagons, you get rotations. 853 01:25:54,300 --> 01:26:01,590 So a different sort of symmetry. But it seems like they always had a sensitivity to the fact that they they felt like these had some connection, 854 01:26:01,740 --> 01:26:06,990 although they never had the language until the 19th century. For us to be able to say, why are these? 855 01:26:06,990 --> 01:26:11,310 Why do you feel like these should be in the same bit of the past? But I think it is. 856 01:26:11,790 --> 01:26:14,990 That's why it comes back to the other question. 857 01:26:15,000 --> 01:26:19,139 So I think having this combination of ways of looking at the world, 858 01:26:19,140 --> 01:26:26,580 why having an artistic sentiments as a mathematician is a very helpful one in creating new possibilities. 859 01:26:27,030 --> 01:26:32,260 And in a way you see the artistic side running ahead of the mathematical side in the Alhambra. 860 01:26:37,490 --> 01:26:52,129 Is there another question here? I just think, yeah, I just study fractals for school. 861 01:26:52,130 --> 01:27:02,300 And I was wondering, does it make any sense and is it worth studying symmetry in a real value dimension of that's great to do because you want say, 862 01:27:02,300 --> 01:27:08,060 well, fractals are kind of the most magical thing because of all that's kind of strange. 863 01:27:08,180 --> 01:27:13,010 But actually there's a symmetry, a different sort of symmetry happening here, which is a symmetry scale. 864 01:27:13,880 --> 01:27:16,700 So that's another move that you could make use of. 865 01:27:16,700 --> 01:27:23,359 Zoom in and then suddenly you see the same thing repeating itself and then you get this infinite repetition of the fractal. 866 01:27:23,360 --> 01:27:32,580 So that's actually symmetry is a very powerful tool in seeing in areas which doesn't look like it should have any sort of impact for, 867 01:27:32,600 --> 01:27:38,120 say, symmetry in the world. Or perhaps the geometry is still very powerful. 868 01:27:38,510 --> 01:27:49,240 So, yes. How do people go about attacking problems like. 869 01:27:49,600 --> 01:27:55,600 Trying to classify all of the potential building blocks for symmetries and discovering things like this monster group, 870 01:27:55,600 --> 01:27:59,380 which is certainly not an object that you just trip on out in the street or walking around. 871 01:27:59,590 --> 01:28:04,540 Yeah, that's a that is one of the eternal mysteries. 872 01:28:04,540 --> 01:28:09,040 And when you're a research mathematician, I wish I knew the answer what the solution is. 873 01:28:09,220 --> 01:28:15,610 And it is about playing around with these and any kind of and it's kind of intriguing that there 874 01:28:15,610 --> 01:28:20,110 were periods in trying to understand the classification of the building blocks of symmetry. 875 01:28:20,380 --> 01:28:27,220 What I think people just had the impression this is never going to end, we're never going to find all of the things. 876 01:28:27,220 --> 01:28:35,470 And we you know, perhaps this is just beyond the capacity of the human brain, even when flying across the globe of the whole community. 877 01:28:37,040 --> 01:28:40,520 But as you put more and more restrictions on I mean, the monster. 878 01:28:40,720 --> 01:28:44,200 Exactly. It's it's a little bit like fundamental particles. 879 01:28:44,200 --> 01:28:50,360 The monsters was predicted because of conditions that it had before it was ever constructed. 880 01:28:50,380 --> 01:28:57,040 So there was a thing like that should be an object with these particular properties because we can't find any reason why they shouldn't be. 881 01:28:57,250 --> 01:29:04,930 And so the conjecture, they were such that somebody conjectured there should be an object with this number of symmetries and certain properties. 882 01:29:05,210 --> 01:29:08,020 And the challenge was, okay, well, let's try and build this thing. 883 01:29:08,400 --> 01:29:18,280 And if we can use a very complex object, yet at its heart is what do you need when you're doing these properties to break down into smaller pieces? 884 01:29:18,520 --> 01:29:22,540 And the smaller piece in the case of the monster was what you might say is not smaller. 885 01:29:22,560 --> 01:29:29,980 That and there's a way to pack 24 dimensional oranges, something called the beach lattice, which we knew about. 886 01:29:29,980 --> 01:29:33,400 And the centrepiece of that we started is it gave us the way to build. 887 01:29:33,670 --> 01:29:40,870 So you sort of these smaller jigsaw bits very often to help you to piece together to make a larger story. 888 01:29:41,470 --> 01:29:53,440 But in the case of the story of symmetry, it's a wonderful example out of many hundreds of mathematicians were involved in sort of exploring this, 889 01:29:53,450 --> 01:29:59,529 it was a bit like going out and exploring, finding new continents for archipelago of islands, 890 01:29:59,530 --> 01:30:09,670 which seem to have nothing to do with anything that your home actually has a vague thought that maybe we we didn't think we found. 891 01:30:10,150 --> 01:30:14,440 But he says we could easily have some or will have on these estimates. 892 01:30:14,440 --> 01:30:17,230 Also, he thinks that there might be a chance, 893 01:30:17,890 --> 01:30:27,810 there might be something out there that we that we miss because we thought our conditions that it couldn't be satisfied, which actually they could. 894 01:30:27,820 --> 01:30:31,870 So he has a theory, which is that I mean, you know, it's a strange thing, 895 01:30:32,530 --> 01:30:37,180 this sort of tension between wanting to prove the conjecture you're working on. 896 01:30:37,390 --> 01:30:45,400 But when he proved it, it's a sort of melancholy because, you know, you've been with that in conjecture for so long. 897 01:30:45,400 --> 01:30:48,860 And I think when Fermat's Last Theorem proved and we all love. 898 01:30:48,860 --> 01:30:56,600 And was he finished? No, but there was another guy. And by this I only realise that that's not such a motivating problem for us. 899 01:30:57,370 --> 01:31:02,950 It was kind of a know, I think it was a moment of sadness in life, wonderful cracks. 900 01:31:03,280 --> 01:31:10,480 And there was the same symmetry. It was like, Oh gosh, let's do more questions that. 901 01:31:15,710 --> 01:31:22,070 I think we should finish there. It's not what you wants to do tomorrow, so thank you for doing great. 902 01:31:37,410 --> 01:31:55,860 Sorry. You only had one. 903 01:31:56,260 --> 01:31:59,770 Yeah, it was just. Hello? I'm not sure where to start. 904 01:31:59,800 --> 01:32:04,450 Where we got me, actually. Uh, yeah. 905 01:32:04,690 --> 01:32:07,720 Just seeing Charlie. Yeah. Yeah, I just. I just took our. 906 01:32:37,250 --> 01:32:44,410 Oh, that is sound. No. 907 01:32:44,670 --> 01:33:00,050 Because you. It's. 908 01:33:03,860 --> 01:33:17,140 And I tried. On the 30th of May 1832, a gunshot was heard ringing out across the 30 on this one in Paris. 909 01:33:17,650 --> 01:33:19,780 Apparently it was walking to market that morning, 910 01:33:19,780 --> 01:33:28,590 ran towards where the gunshot came from and on the ground and found a young man arriving in a garden, clearly killed by a shooting range. 911 01:33:29,020 --> 01:33:34,719 The young man's name was every single gunman was taken to the local hospital, 912 01:33:34,720 --> 01:33:39,490 the coaching hospital where he died the next morning in the arms of his brother Alfred. 913 01:33:39,580 --> 01:33:43,840 And he said to his brother on his death, he says, Don't cry from me, Alfred. 914 01:33:43,840 --> 01:33:48,190 I need all the courage I can muster to die at the age of 20. 915 01:33:49,150 --> 01:33:52,270 I hope likely will at you was about that morning. 916 01:33:52,960 --> 01:33:57,750 It must have been between Valois and a friend of his over a woman that they were both in love with them. 917 01:33:57,890 --> 01:34:04,150 Others suggested that, in fact, it was the establishment trying to get rid of this troublesome revolutionary. 918 01:34:04,780 --> 01:34:11,230 There's even a conjecture that Galois staged his own dance in order to try and spark a new revolution in Paris. 919 01:34:11,800 --> 01:34:14,980 What happened to Clay? What statue was about that morning? 920 01:34:15,170 --> 01:34:22,450 This actually wasn't revolutionary politics, which Galois was famous because a few years earlier, while still at school. 921 01:34:22,840 --> 01:34:31,669 That was so one of the great unsolved problems in mathematics versions of the academicians in Paris trying to explain his great breakthrough. 922 01:34:31,670 --> 01:34:38,950 But unfortunately, the academicians couldn't understand what on earth he was writing about, only because this is how he wrote most of his mathematics. 923 01:34:39,760 --> 01:34:41,680 But anyway, the night before that June, 924 01:34:41,980 --> 01:34:48,080 I realised that this probably was the last opportunity he was going to have to try and explain his great breakthrough. 925 01:34:48,100 --> 01:34:52,659 So he stayed up all night writing in a letter to a friend trying to articulate this great 926 01:34:52,660 --> 01:34:58,990 breakthrough as the Sun appeared over the new day and he went out to meet his destiny. 927 01:34:59,320 --> 01:35:03,620 Maybe the fact that he was doing maths all night, the fact that he was such a bad shot that morning. 928 01:35:03,660 --> 01:35:08,229 But actually, those documents that he left behind on the desk, 929 01:35:08,230 --> 01:35:13,570 which many of us regard as some of the most important documents in the history of mathematics, 930 01:35:13,570 --> 01:35:16,750 because hidden inside, there was a new language, 931 01:35:16,990 --> 01:35:25,690 a language to understand one of the most important concepts in mathematics and science, namely the subject of symmetry. 932 01:35:25,960 --> 01:35:28,390 This new language was called group theory.