1 00:00:03,900 --> 00:00:06,219 STEPHEN HAWKING: Let me take you back in time 2 00:00:06,220 --> 00:00:10,219 to a place without the wonders of the modern world. 3 00:00:11,780 --> 00:00:14,939 500 years ago, the Earth was dark, 4 00:00:14,940 --> 00:00:18,939 a place of mystery and superstition. 5 00:00:27,900 --> 00:00:31,899 But then science changed everything. 6 00:00:40,260 --> 00:00:42,539 This series will tell the stories 7 00:00:42,540 --> 00:00:46,539 of the British scientists who changed the world. 8 00:00:48,660 --> 00:00:52,659 We have asked some of the great scientists and inventors of today 9 00:00:53,020 --> 00:00:55,979 to tell us about their heroes. 10 00:00:55,980 --> 00:00:58,139 Now let's start her up. 11 00:00:58,140 --> 00:01:02,139 It opened up a whole new world of the very small. 12 00:01:03,900 --> 00:01:07,899 Heat was Thomson's big idea. To me, Hunter is a true hero. 13 00:01:07,980 --> 00:01:09,339 Exciting possibilities. 14 00:01:09,340 --> 00:01:13,339 He made science in Britain really matter. 15 00:01:14,060 --> 00:01:18,059 Britain has a tremendous scientific legacy 16 00:01:18,220 --> 00:01:21,979 that most people know little about. 17 00:01:21,980 --> 00:01:25,259 We want to set the record straight 18 00:01:25,260 --> 00:01:29,259 and put science back on the map. 19 00:01:29,860 --> 00:01:33,859 The world is full of wonders, but they become more wonderful 20 00:01:33,980 --> 00:01:37,979 when science looks at them. 21 00:01:50,060 --> 00:01:53,819 STEPHEN HAWKING: I was born in January 1942 22 00:01:53,820 --> 00:01:57,819 when Britain was in the midst of the darkness of war. 23 00:01:58,300 --> 00:02:02,299 With London in ruins, no-one then would have predicted 24 00:02:03,740 --> 00:02:06,659 a bright future for British science. 25 00:02:06,660 --> 00:02:10,659 But I found myself growing up in an era of astonishing discoveries. 26 00:02:16,900 --> 00:02:20,499 For all the achievements of those who had gone before, 27 00:02:20,500 --> 00:02:24,499 two big questions remain to be answered. 28 00:02:28,700 --> 00:02:32,699 One was, how did the universe begin? 29 00:02:33,380 --> 00:02:37,379 And the other, what is the secret of life? 30 00:02:40,940 --> 00:02:44,939 We want to tell you the story of these great breakthroughs, 31 00:02:45,220 --> 00:02:49,219 show you some of the most exciting recent discoveries... 32 00:02:50,100 --> 00:02:54,019 and ask each other the questions that most puzzle us. 33 00:02:54,020 --> 00:02:58,019 Do you think there will be scientific geniuses in a world of super-computers? 34 00:03:12,860 --> 00:03:16,419 RICHARD DAWKINS: Cambridge after the war was a city of battle-weary academics 35 00:03:16,420 --> 00:03:19,379 and students who had already seen the harsh side of life. 36 00:03:19,380 --> 00:03:23,379 This small university city was about to be the centre 37 00:03:24,820 --> 00:03:28,819 for not one, but two of the most significant discoveries ever made. 38 00:03:32,940 --> 00:03:35,459 On February 28th 1953, 39 00:03:35,460 --> 00:03:39,459 two rather wild young men burst into this pub in Cambridge, The Eagle, 40 00:03:40,700 --> 00:03:42,899 and announced to anyone who would listen 41 00:03:42,900 --> 00:03:45,139 that they had discovered the secret of life. 42 00:03:45,140 --> 00:03:49,139 What they discovered was the structure of DNA, 43 00:03:49,340 --> 00:03:50,739 the genetic molecule, 44 00:03:50,740 --> 00:03:54,739 the physical trace of the universal database of all life. 45 00:03:56,340 --> 00:03:58,659 It was more than just a structure. 46 00:03:58,660 --> 00:04:01,939 Written all over it was what it does. 47 00:04:01,940 --> 00:04:05,939 It has the extraordinary capacity to make almost exact copies of itself. 48 00:04:13,860 --> 00:04:16,819 Like every biologist of my generation, 49 00:04:16,820 --> 00:04:20,619 I'm hugely indebted to those wild young men 50 00:04:20,620 --> 00:04:23,459 and their truly inspirational research. 51 00:04:23,460 --> 00:04:27,459 They were an unlikely pair, not what Cambridge was used to. 52 00:04:28,700 --> 00:04:32,699 The brilliant, drivingly ambitious young American, Jim Watson, 53 00:04:32,940 --> 00:04:36,379 and his clever, larger-than-life English colleague, 54 00:04:36,380 --> 00:04:38,339 the garrulous Francis Crick. 55 00:04:38,340 --> 00:04:41,579 They were irreverent, arrogant even, 56 00:04:41,580 --> 00:04:44,779 searching for nothing less than the secret of life, 57 00:04:44,780 --> 00:04:46,779 what Watson himself referred to 58 00:04:46,780 --> 00:04:50,779 as the most important event in biology since Darwin. 59 00:04:55,260 --> 00:04:57,419 Nearly 100 years earlier, 60 00:04:57,420 --> 00:05:01,379 Charles Darwin had published his great book, The Origin Of Species, 61 00:05:01,380 --> 00:05:05,379 and the theory of evolution broke upon the world. 62 00:05:07,100 --> 00:05:11,099 But while Darwin's theory explained how life had evolved, 63 00:05:11,180 --> 00:05:15,179 one key piece of explanation was missing. 64 00:05:17,900 --> 00:05:21,899 How and why was this information passed down from parent to child? 65 00:05:28,740 --> 00:05:31,099 That is the secret of life, 66 00:05:31,100 --> 00:05:34,859 and for a generation that had just gone through a devastating world war, 67 00:05:34,860 --> 00:05:38,859 solving this mystery was one of the great challenges facing science. 68 00:05:41,020 --> 00:05:45,019 In this quest, Crick and Watson had one great advantage. 69 00:05:46,980 --> 00:05:50,939 Each other. 70 00:05:50,940 --> 00:05:54,299 If, for example, I had some idea 71 00:05:54,300 --> 00:05:56,939 which as it turned out would, say, be quite wrong, 72 00:05:56,940 --> 00:05:58,339 was going off at a tangent, 73 00:05:58,340 --> 00:06:00,859 Watson would tell me in no uncertain terms this was nonsense. 74 00:06:00,860 --> 00:06:04,179 Well, Francis likes to talk. 75 00:06:04,180 --> 00:06:06,419 It's his dominant quality, I think. 76 00:06:06,420 --> 00:06:09,659 He doesn't stop unless he gets tired or he thinks the idea's no good. 77 00:06:09,660 --> 00:06:13,659 It's useless working with somebody who's either much too junior than yourself 78 00:06:14,140 --> 00:06:17,019 or much too senior, because then politeness creeps in, 79 00:06:17,020 --> 00:06:21,019 and this is the end of all real collaboration in science. 80 00:06:22,380 --> 00:06:25,859 Crick and Watson understood each other. That was essential. 81 00:06:25,860 --> 00:06:29,859 But the problem before them was immense. 82 00:06:30,020 --> 00:06:34,019 For some decades, scientists had thought that a substance called DNA, 83 00:06:34,540 --> 00:06:37,539 found in all living cells, might play a key role 84 00:06:37,540 --> 00:06:41,539 in transferring information from one generation to another. 85 00:06:41,940 --> 00:06:44,739 But no-one knew how it could do this. 86 00:06:44,740 --> 00:06:47,979 Perhaps if they could see into its structure, 87 00:06:47,980 --> 00:06:50,659 they might be able to discover how it worked. 88 00:06:50,660 --> 00:06:54,659 But looking closely at DNA was very difficult. 89 00:06:55,860 --> 00:06:59,859 Direct visualisation, as with a microscope, couldn't work. 90 00:06:59,860 --> 00:07:01,659 The scale was too small. 91 00:07:01,660 --> 00:07:04,539 But there was an indirect method involving X-rays, 92 00:07:04,540 --> 00:07:08,539 and X-rays were already being beamed at crystals of DNA, 93 00:07:09,380 --> 00:07:13,379 just 50 miles away, in London. 94 00:07:18,980 --> 00:07:22,499 OLIVIA JUDSON: She is one of the heroines of British science, 95 00:07:22,500 --> 00:07:26,499 sometimes called the "Dark Lady of DNA". 96 00:07:27,100 --> 00:07:31,099 Her name was Rosalind Franklin. 97 00:07:33,140 --> 00:07:37,139 A young woman in the then male-dominated world of King's College, London, 98 00:07:37,140 --> 00:07:41,139 she, like Crick and Watson, was trying to visualize the structure of DNA. 99 00:07:44,340 --> 00:07:46,899 And Rosalind had skill on her side. 100 00:07:46,900 --> 00:07:49,459 She was an expert in X-ray diffraction, 101 00:07:49,460 --> 00:07:53,459 a way of capturing images of atomic structure. 102 00:07:54,580 --> 00:07:58,579 But the kit she had to work with was incredibly basic. 103 00:07:59,500 --> 00:08:02,939 The new biophysics department at King's was a pretty ramshackle place. 104 00:08:02,940 --> 00:08:06,539 A lot of the equipment was borrowed from colleagues at other London colleges 105 00:08:06,540 --> 00:08:07,979 and this camera was army surplus. 106 00:08:07,980 --> 00:08:11,979 The DNA came from the thymus gland of a calf in Switzerland 107 00:08:12,940 --> 00:08:16,939 and in order to take pictures of it, it had to be suspended on a paper clip. 108 00:08:17,620 --> 00:08:19,499 You put it in here, 109 00:08:19,500 --> 00:08:22,339 you look through the eyepiece and line it up to make sure it's straight, 110 00:08:22,340 --> 00:08:26,339 then you put a piece of photographic paper here and bombard it with X-rays. 111 00:08:27,700 --> 00:08:29,659 The X-rays hit the crystal 112 00:08:29,660 --> 00:08:32,699 and scatter the light, giving you a pattern of dots. 113 00:08:32,700 --> 00:08:36,699 If the image is sharp enough and the sample was lined up properly, 114 00:08:36,780 --> 00:08:40,779 you might be able to work out what the structure of the crystal is. 115 00:08:44,020 --> 00:08:48,019 Rosalind was extremely determined - little would stop her. 116 00:08:49,980 --> 00:08:53,819 The X-rays were done at night when there weren't many people around 117 00:08:53,820 --> 00:08:57,819 because King's College was afraid there might be leaks from the lab. 118 00:08:58,460 --> 00:09:01,539 But it wasn't Rosalind who made the first breakthrough. 119 00:09:01,540 --> 00:09:05,539 It was her colleague, Maurice Wilkins. 120 00:09:07,460 --> 00:09:10,779 Early in 1951, Maurice Wilkins took a photograph of DNA 121 00:09:10,780 --> 00:09:13,099 that suggested it had a regular structure. 122 00:09:13,100 --> 00:09:16,819 The story goes that one night, he came outside for a breath of fresh air 123 00:09:16,820 --> 00:09:20,819 and looked across the river at the OXO Tower. 124 00:09:22,900 --> 00:09:26,779 The famous logo gave him an idea. 125 00:09:26,780 --> 00:09:29,539 Perhaps the structure in the picture was shaped like an X, 126 00:09:29,540 --> 00:09:33,539 which might mean DNA was a helix, or spiral shape. 127 00:09:37,180 --> 00:09:39,339 This was a vital insight 128 00:09:39,340 --> 00:09:43,339 and perhaps, if they had been able to work together, Maurice and Rosalind 129 00:09:43,940 --> 00:09:46,979 could between them have begun to crack the mystery. 130 00:09:46,980 --> 00:09:50,979 But that was never going to happen. 131 00:09:54,260 --> 00:09:55,819 Rosalind comes across 132 00:09:55,820 --> 00:09:59,179 as a very private person, a loyal and thoughtful friend, 133 00:09:59,180 --> 00:10:02,339 very honest, a brilliant scientist and a dedicated one. 134 00:10:02,340 --> 00:10:06,339 But she also had a fierce temper and contempt for those she didn't respect. 135 00:10:06,500 --> 00:10:10,499 She refused to collaborate with Wilkins and didn't show him her data. 136 00:10:12,860 --> 00:10:14,579 So when she took this photo, 137 00:10:14,580 --> 00:10:18,579 she didn't show it to Wilkins, or indeed, anyone else. 138 00:10:19,820 --> 00:10:23,819 This is the famous photo 51, a blurry image, 139 00:10:24,260 --> 00:10:28,259 but one which holds the key to the secret of life. 140 00:10:28,380 --> 00:10:32,379 In this picture are vital clues needed to discover the shape of DNA. 141 00:10:36,860 --> 00:10:40,259 But Rosalind Franklin tucked the picture away in a drawer, 142 00:10:40,260 --> 00:10:44,259 and there it might have stayed, if it wasn't for Wilkins. 143 00:10:46,780 --> 00:10:50,779 Over eight months later, in January 1953, 144 00:10:51,300 --> 00:10:54,539 James Watson made one of his occasional visits to King's. 145 00:10:54,540 --> 00:10:58,179 Wilkins, who worked in the same lab as Rosalind, 146 00:10:58,180 --> 00:11:02,179 said he had something to show him. 147 00:11:07,860 --> 00:11:11,099 For Watson and Crick, this was the crucial piece of evidence, 148 00:11:11,100 --> 00:11:14,339 the clue that would allow them to deduce the structure of DNA. 149 00:11:14,340 --> 00:11:18,339 The pattern of spots on photo 51 showed clearly that DNA was a helix. 150 00:11:22,500 --> 00:11:26,259 RICHARD DAWKINS: Watson saw immediately the value of this information. 151 00:11:26,260 --> 00:11:30,259 He hotfooted it back to Cambridge with this vital clue. 152 00:11:30,340 --> 00:11:34,019 But it's what he and Crick did next that made all the difference. 153 00:11:34,020 --> 00:11:38,019 They knew it was a helix, but now the question was, what sort of helix? 154 00:11:38,740 --> 00:11:42,739 Their approach was very hands on, making giant 3-D models 155 00:11:43,060 --> 00:11:47,059 of all the different shapes they could think of that might fit the picture. 156 00:11:48,260 --> 00:11:49,779 They tried model after model, 157 00:11:49,780 --> 00:11:53,419 each one a hypothesis for a three-dimensional structure 158 00:11:53,420 --> 00:11:57,419 that might explain Franklin's X-ray results. 159 00:11:58,220 --> 00:12:02,219 Watson and Crick worked at a furious rate. 160 00:12:02,740 --> 00:12:06,579 The machine shop which supplied them with the tin bases for their models 161 00:12:06,580 --> 00:12:08,179 struggled to keep up. 162 00:12:08,180 --> 00:12:12,179 But the pieces of the puzzle all fell into place in February 1953. 163 00:12:19,300 --> 00:12:23,059 Rosalind Franklin's X-ray pictures, and her measurements on them, 164 00:12:23,060 --> 00:12:27,059 enabled Watson and Crick to work out that DNA had to be a double helix. 165 00:12:28,780 --> 00:12:31,819 Their original model has unfortunately been destroyed. 166 00:12:31,820 --> 00:12:34,419 This is a half-scale replica. 167 00:12:34,420 --> 00:12:38,019 You can see the two spirals going around like that, 168 00:12:38,020 --> 00:12:40,819 forming a kind of spiral staircase, 169 00:12:40,820 --> 00:12:44,819 and the steps of the spiral staircase are the so-called bases. 170 00:12:45,380 --> 00:12:47,539 There are only four kinds of them 171 00:12:47,540 --> 00:12:51,539 and they are in pairs - each step is one pair. 172 00:12:56,260 --> 00:13:00,259 The shape plays a vital role in the way DNA works 173 00:13:00,700 --> 00:13:04,699 because the double helix can split perfectly and then re-form. 174 00:13:07,740 --> 00:13:09,859 The reason we're all different 175 00:13:09,860 --> 00:13:13,859 is that we're born with our own particular sequence of these base pairs, 176 00:13:14,620 --> 00:13:18,619 with half of each pair inherited from each of our parents. 177 00:13:24,940 --> 00:13:28,179 Crick and Watson had indeed made the first step 178 00:13:28,180 --> 00:13:32,179 to uncovering the secret of life. 179 00:13:35,260 --> 00:13:37,699 They'd done it. 180 00:13:37,700 --> 00:13:39,699 Surely they'd had a lot of luck 181 00:13:39,700 --> 00:13:42,299 but let's not take away from their achievement. 182 00:13:42,300 --> 00:13:44,259 As Crick himself said, 183 00:13:44,260 --> 00:13:47,739 "It's true that by blundering about we stumbled on gold, 184 00:13:47,740 --> 00:13:49,859 "but we were looking for gold." 185 00:13:49,860 --> 00:13:52,059 And the biggest nugget of all? 186 00:13:52,060 --> 00:13:56,059 Forget all mystical ideas of an essence of life or a life force. 187 00:13:57,180 --> 00:14:01,179 From now on, the essence of life was just bytes and bytes and bytes 188 00:14:03,020 --> 00:14:07,019 of digital information. 189 00:14:15,060 --> 00:14:16,819 But the story didn't end there. 190 00:14:16,820 --> 00:14:18,859 What's perhaps even more exciting 191 00:14:18,860 --> 00:14:21,459 than what Watson and Crick did in the 1950s 192 00:14:21,460 --> 00:14:25,459 was what Crick went on to do in the 1960s. 193 00:14:25,540 --> 00:14:29,539 Cracking the genetic code itself. 194 00:14:30,140 --> 00:14:34,139 Crick knew that DNA was information, a code for life. 195 00:14:34,380 --> 00:14:38,379 A message lurked in the sequence of DNA bases which was translated 196 00:14:38,780 --> 00:14:42,779 into a corresponding sequence in a different kind of molecule - protein. 197 00:14:43,820 --> 00:14:45,419 There must be a dictionary, 198 00:14:45,420 --> 00:14:49,419 a look-up table, from DNA sequences to protein sequences. 199 00:14:50,260 --> 00:14:53,099 That was the elusive genetic code, 200 00:14:53,100 --> 00:14:56,099 and that was what Crick set out to break, 201 00:14:56,100 --> 00:15:00,099 and what he came up with was an ingenious experiment. 202 00:15:01,460 --> 00:15:05,459 He began with a virus and then mutated its DNA. 203 00:15:06,020 --> 00:15:08,819 He found that if he removed a single base, 204 00:15:08,820 --> 00:15:11,019 the virus would no longer work. 205 00:15:11,020 --> 00:15:15,019 This meant the original message the virus DNA was carrying was disrupted. 206 00:15:15,820 --> 00:15:19,539 The same was true when he removed two bases. 207 00:15:19,540 --> 00:15:23,539 If he removed three bases, however, the original message was restored. 208 00:15:24,580 --> 00:15:28,299 The virus was back to normal. 209 00:15:28,300 --> 00:15:32,299 It now remained for others to fill in exactly what each triplet means, 210 00:15:32,420 --> 00:15:36,419 but perhaps the vital step in the whole molecular genetic revolution 211 00:15:37,060 --> 00:15:39,939 was Crick's discovery that it was a triplet code. 212 00:15:39,940 --> 00:15:43,019 It opened up a whole new world of understanding 213 00:15:43,020 --> 00:15:45,259 that couldn't have been dreamed of 214 00:15:45,260 --> 00:15:49,259 before Crick and his colleagues came on the scene. 215 00:15:49,900 --> 00:15:53,899 Since this great discovery, the advances have come thick and fast. 216 00:15:53,980 --> 00:15:57,979 We now have a biotech industry worth billions. 217 00:15:59,660 --> 00:16:03,659 We can identify medical problems in the womb, identify crime suspects 218 00:16:04,460 --> 00:16:07,219 using unique DNA fingerprints, 219 00:16:07,220 --> 00:16:10,579 sequence the entire human genome 220 00:16:10,580 --> 00:16:14,579 and even clone new life. 221 00:16:24,140 --> 00:16:28,139 While Watson and Crick struggled to solve the mystery of life, 222 00:16:28,900 --> 00:16:30,419 in another part of Cambridge, 223 00:16:30,420 --> 00:16:34,419 the physicists had their own big question - 224 00:16:34,620 --> 00:16:38,619 how did the universe begin? 225 00:16:43,580 --> 00:16:47,579 While Crick and Watson were unravelling the shape of DNA, 226 00:16:47,700 --> 00:16:51,699 another huge question was being tackled just a few hundred yards away. 227 00:16:55,260 --> 00:16:57,339 How did the universe begin? 228 00:16:57,340 --> 00:17:01,339 It's the question I have spent my life grappling with. 229 00:17:01,740 --> 00:17:05,659 The story starts for me with the controversial genius 230 00:17:05,660 --> 00:17:09,659 who was one of my inspirations for studying at Cambridge. 231 00:17:09,980 --> 00:17:13,979 Fred Hoyle. 232 00:17:15,540 --> 00:17:17,259 JIM AL-KHALILI: In 1948, 233 00:17:17,260 --> 00:17:21,259 the nation listened enthralled to a series of radio broadcasts 234 00:17:21,980 --> 00:17:25,979 from a gruff Northerner, describing the inner workings of the universe. 235 00:17:27,140 --> 00:17:30,019 FRED HOYLE ON RADIO: Well, then, what is the stars? 236 00:17:30,020 --> 00:17:34,019 What is the insides of the stars, and what is in the depths of space 237 00:17:34,500 --> 00:17:38,499 beyond the bright girdle of the Milky Way? Come to that, what is the universe? 238 00:17:39,900 --> 00:17:42,379 AL-KHALILI: One producer said that Fred Hoyle 239 00:17:42,380 --> 00:17:46,379 described interstellar space as if it were a cricket match. 240 00:17:47,740 --> 00:17:51,739 But Hoyle did more than bring the universe into our living rooms. 241 00:17:52,060 --> 00:17:56,059 He revolutionised our understanding of it, and of ourselves. 242 00:17:57,980 --> 00:18:01,979 For 25 years, Fred Hoyle was the most famous astrophysicist in the world, 243 00:18:03,500 --> 00:18:07,499 and the man who kick-started the debate about the origins of the universe. 244 00:18:10,060 --> 00:18:14,059 I've come to where he was born, in the village of Gilstead, 245 00:18:15,540 --> 00:18:19,539 to find out where his interest came from. 246 00:18:21,460 --> 00:18:24,859 You might think of scientists as being a bit geeky, 247 00:18:24,860 --> 00:18:28,579 heads always buried in books, always studying. 248 00:18:28,580 --> 00:18:30,859 Well, Fred Hoyle wasn't like that. 249 00:18:30,860 --> 00:18:34,619 He was always playing truant from school, either down by the canal 250 00:18:34,620 --> 00:18:38,619 near where he lived, or out here on the moors, even in weather like this. 251 00:18:39,060 --> 00:18:43,059 In fact, he loved the outdoor life, hiking, mountaineering. 252 00:18:43,060 --> 00:18:47,059 He even courted his wife-to-be while out on a hiking trip. 253 00:18:47,140 --> 00:18:50,219 But there's another side to Fred Hoyle. 254 00:18:50,220 --> 00:18:54,219 Curiosity. 255 00:18:55,620 --> 00:18:59,619 He used to say about the hours he spent mucking about on the canal 256 00:19:00,780 --> 00:19:04,779 that he was instinctively displaying a sound sense of engineering. 257 00:19:05,180 --> 00:19:08,779 Watching the lock gates and the sluices open and close 258 00:19:08,780 --> 00:19:11,019 was much more valuable, 259 00:19:11,020 --> 00:19:15,019 he thought, than anything he could have learnt at school. 260 00:19:15,380 --> 00:19:19,379 Even at an early age, Hoyle was remarkably self-confident. 261 00:19:20,580 --> 00:19:23,379 "Cocky" might be a better word to describe him. 262 00:19:23,380 --> 00:19:27,379 And throughout his time at Cambridge, he was famous for his belligerence 263 00:19:27,620 --> 00:19:29,419 and for speaking his mind. 264 00:19:29,420 --> 00:19:31,859 And he was a constant thorn in the side 265 00:19:31,860 --> 00:19:35,859 of the British scientific establishment. 266 00:19:42,020 --> 00:19:46,019 Hoyle turned his attention to the biggest question of all. 267 00:19:46,660 --> 00:19:50,659 How did the universe begin? 268 00:19:50,820 --> 00:19:54,819 By this time, scientists knew that the universe was constantly expanding, 269 00:19:56,620 --> 00:20:00,219 but why hadn't it run out of steam? 270 00:20:00,220 --> 00:20:03,939 And where had it started from? 271 00:20:03,940 --> 00:20:06,939 Hoyle enlisted the help of two old friends 272 00:20:06,940 --> 00:20:09,899 from his wartime days in radar research, 273 00:20:09,900 --> 00:20:12,819 Hermann Bondi and Thomas Gold, 274 00:20:12,820 --> 00:20:16,819 and the three of them spent hours here in Bondi's rooms in Trinity College 275 00:20:18,660 --> 00:20:22,659 talking, arguing and just plain thinking. 276 00:20:24,460 --> 00:20:27,139 But when the eureka moment came, 277 00:20:27,140 --> 00:20:31,139 it was quite sudden and from an unexpected source. 278 00:20:31,700 --> 00:20:35,699 Hoyle, Gold and Bondi went to see the thriller Dead Of Night, 279 00:20:36,540 --> 00:20:40,499 a kind of 1940s version of Groundhog Day, 280 00:20:40,500 --> 00:20:44,499 when the hero is trapped in a repeating pattern of events. 281 00:20:47,620 --> 00:20:51,179 The film is about a recurring nightmare, 282 00:20:51,180 --> 00:20:54,139 and when Gold next saw Hoyle and Bondi, 283 00:20:54,140 --> 00:20:58,139 he said, "Suppose the universe is like that, with no beginning and no end? 284 00:20:58,460 --> 00:21:00,699 "Just constantly recycling." 285 00:21:00,700 --> 00:21:03,019 Hoyle and Bondi seized on the idea 286 00:21:03,020 --> 00:21:07,019 and they made it the basis of their brand-new theories of the universe. 287 00:21:08,580 --> 00:21:12,579 What Hoyle suggested was that the universe didn't begin suddenly 288 00:21:13,940 --> 00:21:17,939 but had always been there in what he called a "steady state". 289 00:21:19,300 --> 00:21:23,299 I remember, I think it was on 10th February 1948, 290 00:21:23,580 --> 00:21:27,579 that one evening I got down and really got the equations on paper. 291 00:21:28,660 --> 00:21:32,459 I remember I had them somewhere about ten o'clock in the evening, 292 00:21:32,460 --> 00:21:34,099 and I sat up till three in the morning, 293 00:21:34,100 --> 00:21:38,099 and by then, I had the solution that I wanted. 294 00:21:38,140 --> 00:21:42,139 In Hoyle's universe, galaxies speed away from each other 295 00:21:43,060 --> 00:21:47,059 and new matter is continuously created to fill the gaps they leave behind. 296 00:21:49,380 --> 00:21:51,939 These ideas were controversial, 297 00:21:51,940 --> 00:21:55,659 and Hoyle was keen to let the whole world know about them, 298 00:21:55,660 --> 00:21:59,659 and within a year, he got his chance. 299 00:21:59,940 --> 00:22:03,939 The most obvious question to ask about continuous creation is this - 300 00:22:04,020 --> 00:22:06,859 where does the created material come from? 301 00:22:06,860 --> 00:22:08,859 Well, it doesn't come from anywhere. 302 00:22:08,860 --> 00:22:12,859 Material simply appears, it'screated. 303 00:22:13,100 --> 00:22:17,099 At one time, the various atoms composing the material don't exist, 304 00:22:17,660 --> 00:22:19,779 at a later time, they do. 305 00:22:19,780 --> 00:22:21,579 JIM AL-KHALILI: But it wasn't long 306 00:22:21,580 --> 00:22:25,579 before Hoyle's ideas were challenged by other scientists. 307 00:22:26,380 --> 00:22:30,379 This is a carbon copy of a radio talk he gave in March 1949, 308 00:22:31,900 --> 00:22:35,179 in which he invented the term "big bang". 309 00:22:35,180 --> 00:22:38,019 Now, Hoyle used it as a derogatory term. 310 00:22:38,020 --> 00:22:39,699 He thought it was a bit like 311 00:22:39,700 --> 00:22:42,499 a girl suddenly jumping out of a birthday cake. 312 00:22:42,500 --> 00:22:46,179 It was a party trick, not a real scientific theory. 313 00:22:46,180 --> 00:22:49,299 Here's what he has to say. 314 00:22:49,300 --> 00:22:53,299 "It's an irrational process that cannot be described in scientific terms. 315 00:22:53,700 --> 00:22:57,499 "On philosophical grounds too, I cannot see any good reason 316 00:22:57,500 --> 00:23:01,499 "for preferring the big bang idea." 317 00:23:01,780 --> 00:23:05,779 The idea of the Big Bang is that the universe was created suddenly, 318 00:23:06,980 --> 00:23:10,979 in a single explosive moment. 319 00:23:16,220 --> 00:23:18,939 And while Hoyle poured scorn on the theory, 320 00:23:18,940 --> 00:23:21,219 it was gaining credence 321 00:23:21,220 --> 00:23:24,739 among other scientists. 322 00:23:24,740 --> 00:23:28,099 But Hoyle's capacity to generate ideas, 323 00:23:28,100 --> 00:23:32,099 however controversial, drew students to Cambridge. 324 00:23:33,540 --> 00:23:37,539 Among them was a young PhD student called Stephen Hawking. 325 00:23:44,980 --> 00:23:48,979 Stephen Hawking was destined to become the most famous physicist since Einstein. 326 00:23:53,060 --> 00:23:56,339 But he'd not been a particularly promising child. 327 00:23:56,340 --> 00:23:59,019 He'd not learn to read until he was eight. 328 00:23:59,020 --> 00:24:02,539 He hadn't even been in the top half of his class at school. 329 00:24:02,540 --> 00:24:04,699 And he did make it to Oxford, 330 00:24:04,700 --> 00:24:08,699 but then it was a close-run thing whether he'd get a First. 331 00:24:09,300 --> 00:24:12,739 When he moved to Cambridge to study for his PhD, 332 00:24:12,740 --> 00:24:16,739 Hawking realised that he had no interest in day-to-day astronomy, 333 00:24:17,140 --> 00:24:19,219 and that, like Hoyle, 334 00:24:19,220 --> 00:24:23,219 he wanted to use mathematics to investigate the universe. 335 00:24:24,860 --> 00:24:28,859 The hot topic of research in the 1960s was black holes. 336 00:24:29,340 --> 00:24:31,899 Now, it was Einstein's theory of relativity 337 00:24:31,900 --> 00:24:35,899 that first correctly explained how stars collapse to form black holes. 338 00:24:36,900 --> 00:24:39,259 It said that there are points in the universe 339 00:24:39,260 --> 00:24:43,259 where space is sucked in on itself. 340 00:24:47,140 --> 00:24:51,139 In 1965, mathematical physicist Roger Penrose 341 00:24:52,340 --> 00:24:54,939 devised an equation that explained 342 00:24:54,940 --> 00:24:58,939 how everything was sucked into the centre of a black hole, 343 00:25:00,820 --> 00:25:04,019 creating a sort of plughole in space, 344 00:25:04,020 --> 00:25:08,019 where matter, light and energy disappear, 345 00:25:08,620 --> 00:25:12,619 where time and space end. 346 00:25:12,660 --> 00:25:16,659 It was Hawking's genius to take this idea and reverse it... 347 00:25:19,980 --> 00:25:23,979 ..showing how the Big Bang itself was the opposite of a black hole. 348 00:25:26,220 --> 00:25:30,219 An explosive moment in which the entire universe 349 00:25:30,620 --> 00:25:34,619 emerged from a pinpoint and shot outwards, forever expanding. 350 00:25:37,740 --> 00:25:41,739 At the moment of the Big Bang, black hole behaviour was reversed, 351 00:25:42,940 --> 00:25:46,739 so rather than everything being sucked in, 352 00:25:46,740 --> 00:25:49,699 now space, time and energy 353 00:25:49,700 --> 00:25:53,699 all suddenly burst out of the singularity. 354 00:25:56,980 --> 00:25:59,499 If this explanation was correct, 355 00:25:59,500 --> 00:26:03,499 then Hoyle's steady state theory was simply wrong. 356 00:26:13,700 --> 00:26:16,779 Hawking did much more than cast final doubts 357 00:26:16,780 --> 00:26:20,779 on Hoyle's steady state interpretation of the universe. 358 00:26:22,660 --> 00:26:24,339 He went on to develop a theory 359 00:26:24,340 --> 00:26:28,339 about the behaviour of particles on the edge of a black hole. 360 00:26:30,420 --> 00:26:33,339 He still hopes to develop a mathematical theory 361 00:26:33,340 --> 00:26:36,859 that will draw the many ideas of physics together. 362 00:26:36,860 --> 00:26:40,859 A theory of everything. 363 00:26:45,060 --> 00:26:47,219 HAWKING: Just as Roger Penrose's equation 364 00:26:47,220 --> 00:26:50,259 triggered off my own thoughts about the Big Bang, 365 00:26:50,260 --> 00:26:54,259 so one breakthrough led to another in our understanding of life. 366 00:26:56,660 --> 00:27:00,659 The man who took us one step further was Bill Hamilton. 367 00:27:05,460 --> 00:27:09,019 RICHARD DAWKINS: For more than 30 years, Bill was, variously, 368 00:27:09,020 --> 00:27:13,019 my inspiration, colleague, mentor and friend. 369 00:27:13,220 --> 00:27:15,819 He was a shy and forgetful man, 370 00:27:15,820 --> 00:27:19,819 in equal parts very deep thinker and very knowledgeable naturalist, 371 00:27:20,340 --> 00:27:23,899 rather like Darwin, but with added mathematics. 372 00:27:23,900 --> 00:27:27,899 He thought all the time, seeking biological answers to big questions. 373 00:27:29,300 --> 00:27:32,419 Why do we have sex? Why do we grow old? 374 00:27:32,420 --> 00:27:36,419 But he's best known for his evolutionary explanation of altruism. 375 00:27:37,860 --> 00:27:40,139 Why do animals, including us, 376 00:27:40,140 --> 00:27:44,139 give up our own interests for the sake of others? 377 00:27:45,220 --> 00:27:49,219 I've come to Badgers Mount in Kent, because this is where Bill grew up - 378 00:27:50,540 --> 00:27:52,539 in this house, Oaklea. 379 00:27:52,540 --> 00:27:55,779 To him, it remained a wild paradise all his life, 380 00:27:55,780 --> 00:27:59,779 a laboratory of endless curiosities. 381 00:28:03,980 --> 00:28:07,979 This is Bill's collection of butterflies, made when he was a boy. 382 00:28:07,980 --> 00:28:11,979 All British and all collected within walking distance of this house. 383 00:28:12,980 --> 00:28:16,979 He sometimes joked that he preferred the company of insects to people. 384 00:28:18,740 --> 00:28:21,859 Bill wanted to apply genetics to evolution. 385 00:28:21,860 --> 00:28:25,859 He was fascinated by a big question left over from Darwin - 386 00:28:26,860 --> 00:28:29,259 the mystery of altruism. 387 00:28:29,260 --> 00:28:31,699 Why do animals co-operate? 388 00:28:31,700 --> 00:28:35,699 Why don't we humans run an entirely dog-eat-dog world? 389 00:28:36,180 --> 00:28:40,179 Inspired by the work of the great biologist Sir Ronald Fisher, 390 00:28:40,460 --> 00:28:44,459 he realised that "survival of the fittest" really meant the survival of genes. 391 00:28:46,500 --> 00:28:49,739 In 1964, Bill took off. 392 00:28:49,740 --> 00:28:53,699 In the great tradition of British naturalists like Alfred Russel Wallace, 393 00:28:53,700 --> 00:28:55,979 he took an expedition to the Amazon. 394 00:28:55,980 --> 00:28:58,259 He wanted to study the social insects - 395 00:28:58,260 --> 00:29:00,859 ants, bees, wasps and termites. 396 00:29:00,860 --> 00:29:04,299 Their sterile worker castes fascinated him 397 00:29:04,300 --> 00:29:08,299 as the ultimate genetic altruists. 398 00:29:12,540 --> 00:29:14,619 These are leafcutter ants. 399 00:29:14,620 --> 00:29:16,499 They're native to South America. 400 00:29:16,500 --> 00:29:20,099 They forage for leaves, they cut them and carry them home. 401 00:29:20,100 --> 00:29:22,859 But they don't actually eat the leaves, 402 00:29:22,860 --> 00:29:25,659 but compost them for a fungus which they grow underground. 403 00:29:25,660 --> 00:29:28,099 It's the mushrooms that they eat 404 00:29:28,100 --> 00:29:32,099 and feed to the queen and the larvae and the other workers. 405 00:29:32,180 --> 00:29:36,179 Now, from a Darwinian point of view, that could be called an act of altruism. 406 00:29:37,020 --> 00:29:41,019 The workers are working for the good of the reproduction of another individual, 407 00:29:41,980 --> 00:29:45,779 the queen, and that's a supreme act of self-sacrifice 408 00:29:45,780 --> 00:29:49,779 in a Darwinian world. 409 00:29:49,940 --> 00:29:53,939 Bill worked out that a gene for altruism would survive 410 00:29:54,020 --> 00:29:58,019 if the cost to the individual was exceeded by the benefit it gave to others, 411 00:29:58,900 --> 00:30:02,299 depending on how close the relationship was. 412 00:30:02,300 --> 00:30:05,059 He created a mathematical formula to reflect this, 413 00:30:05,060 --> 00:30:09,059 which became known as Hamilton's rule. 414 00:30:10,300 --> 00:30:14,299 The theory made sense not only of ants and the other social insects, 415 00:30:14,300 --> 00:30:18,219 but it also explains co-operation and mutual support 416 00:30:18,220 --> 00:30:20,739 in a huge range of animals. 417 00:30:20,740 --> 00:30:22,859 Bill Hamilton went on to solve 418 00:30:22,860 --> 00:30:26,259 many other outstanding questions left over from Darwin, 419 00:30:26,260 --> 00:30:28,859 including why we grow old, 420 00:30:28,860 --> 00:30:31,299 why the ratio of males to females is what it is, 421 00:30:31,300 --> 00:30:35,299 and above all, why sexual reproduction evolved at all. 422 00:30:41,420 --> 00:30:44,299 An extraordinary thing about Bill 423 00:30:44,300 --> 00:30:47,019 was the way he wouldn't advertise his own genius. 424 00:30:47,020 --> 00:30:49,579 He'd have a brilliant idea, but then he'd bury it 425 00:30:49,580 --> 00:30:52,379 in the middle of a book review or something like that, 426 00:30:52,380 --> 00:30:54,779 and then attribute it to somebody else later. 427 00:30:54,780 --> 00:30:58,179 I'd then have to show him his own earlier paper 428 00:30:58,180 --> 00:31:02,139 in order to convince him that the idea was really his. 429 00:31:02,140 --> 00:31:04,259 He'd then reluctantly admit it, 430 00:31:04,260 --> 00:31:08,259 but say that the other person had expressed it better. 431 00:31:09,100 --> 00:31:13,099 Bill died from complications arising from malaria at the age of 63. 432 00:31:14,740 --> 00:31:18,459 I vividly remember his funeral. 433 00:31:18,460 --> 00:31:21,779 Perhaps tongue-in-cheek, he'd expressed the hope when he died 434 00:31:21,780 --> 00:31:25,779 that he would be laid out unburied on the floor of the Amazon jungle, 435 00:31:26,500 --> 00:31:29,339 where burying beetles would inter him. 436 00:31:29,340 --> 00:31:32,019 Of course, that's not the way it happened. 437 00:31:32,020 --> 00:31:35,499 Bill is in fact buried on the edge of another famous forest, 438 00:31:35,500 --> 00:31:37,979 Wytham Wood near Oxford. 439 00:31:37,980 --> 00:31:41,179 At the graveside, his companion Louisa 440 00:31:41,180 --> 00:31:44,299 invoked one of Bill's wilder theories, 441 00:31:44,300 --> 00:31:48,059 and painted a picture of bacterial and fungal spores 442 00:31:48,060 --> 00:31:50,859 carrying him up into the clouds 443 00:31:50,860 --> 00:31:54,859 where he might eventually be rained down onto the forests of his beloved Amazon. 444 00:32:08,780 --> 00:32:12,779 HAWKING: The speed at which science has advanced since I was born 445 00:32:13,020 --> 00:32:17,019 is breathtaking. 446 00:32:17,700 --> 00:32:21,379 Since we got our first glimpse of how the universe began, 447 00:32:21,380 --> 00:32:25,379 since the structure of DNA revealed the structure of life itself, 448 00:32:27,980 --> 00:32:31,979 British scientists have created the world's first supersonic airliner, 449 00:32:33,100 --> 00:32:37,099 delivered the first test-tube baby, and invented the internet. 450 00:32:39,940 --> 00:32:42,739 So what lies ahead? 451 00:32:42,740 --> 00:32:46,739 What will be the discoveries and inventions of the next 50 years? 452 00:32:52,020 --> 00:32:56,019 JAMES DYSON: I want to show you the new invention that most excites me. 453 00:32:56,340 --> 00:33:00,339 One which promises to transform our world. 454 00:33:01,500 --> 00:33:05,499 The most exciting possibilities of the future lie in nano-technology, 455 00:33:06,900 --> 00:33:09,139 making incredibly strong materials 456 00:33:09,140 --> 00:33:12,259 that are smaller than you can imagine. 457 00:33:12,260 --> 00:33:16,259 These materials could even allow us to build a lift into space. 458 00:33:16,820 --> 00:33:18,939 It's the modern equivalent of prehistoric man 459 00:33:18,940 --> 00:33:21,779 discovering how to work with iron. 460 00:33:21,780 --> 00:33:24,419 I've come to where else but Cambridge, 461 00:33:24,420 --> 00:33:28,419 where some of the most impressive work is being done. 462 00:33:35,740 --> 00:33:39,739 In the past, the strength of a material went hand in hand with its weight - 463 00:33:40,460 --> 00:33:43,219 the stronger it was, the heavier it was. 464 00:33:43,220 --> 00:33:47,139 Then in the 1980s, a British scientist called Harry Kroto 465 00:33:47,140 --> 00:33:50,779 won a Nobel prize for discovering a new type of carbon. 466 00:33:50,780 --> 00:33:54,779 Carbon-60 was the inspiration for carbon nanotubes, 467 00:33:55,540 --> 00:33:59,539 which are incredibly tough but also very light. 468 00:34:01,540 --> 00:34:05,539 Nanotubes are many times stronger than any carbon fibres currently in use. 469 00:34:07,380 --> 00:34:09,179 And the surprising thing about them 470 00:34:09,180 --> 00:34:11,739 is that they're not, in fact, made at all. 471 00:34:11,740 --> 00:34:15,259 They're grown. 472 00:34:15,260 --> 00:34:17,739 The protective clothing is necessary 473 00:34:17,740 --> 00:34:20,779 to stop human hair and flakes of skin damaging the process. 474 00:34:20,780 --> 00:34:24,779 Human hair is 50,000 times fatter than a nanotube 475 00:34:25,660 --> 00:34:29,659 and if it got into the sample, it would ruin it. 476 00:34:34,380 --> 00:34:38,379 Well, this'll be a challenge! The scientists in this lab 477 00:34:38,420 --> 00:34:40,779 are letting me grow my own nanotubes, 478 00:34:40,780 --> 00:34:44,779 and if things go all right, they'll develop on this silicon wafer. 479 00:34:44,780 --> 00:34:47,899 It'll need an electron microscope to see it, of course. 480 00:34:47,900 --> 00:34:51,139 I'll put it on this graphite heater 481 00:34:51,140 --> 00:34:55,139 and put the bell jar over the top. 482 00:34:58,940 --> 00:35:00,659 Now I'll switch on. 483 00:35:00,660 --> 00:35:03,739 That will introduce gases into the bell jar 484 00:35:03,740 --> 00:35:07,659 and the whole thing will heat up to about 700 degrees centigrade. 485 00:35:07,660 --> 00:35:10,419 There's now an electric field between the black shower-head 486 00:35:10,420 --> 00:35:12,219 and the silicon wafer, 487 00:35:12,220 --> 00:35:16,219 and the red glow is the heater which the silicon is sitting on. 488 00:35:19,180 --> 00:35:22,659 This machine produces thousands of nanotubes 489 00:35:22,660 --> 00:35:26,659 too small for the human eye to see. 490 00:35:28,740 --> 00:35:32,459 To give you an idea, a nano is to a football 491 00:35:32,460 --> 00:35:36,459 what a football is to the Earth. 492 00:35:39,900 --> 00:35:43,899 Now I can take my silicon wafer to a scanning electron microscope 493 00:35:45,220 --> 00:35:49,219 to see if I've actually grown any nanotubes. 494 00:35:50,380 --> 00:35:52,499 This microscope has magnification 495 00:35:52,500 --> 00:35:56,499 up to 4,000, even 5,000 times. 496 00:36:00,900 --> 00:36:04,899 Look at that. A great forest of carbon nanotubes. 497 00:36:04,900 --> 00:36:07,979 Their great virtue is that you can make almost any shape you want. 498 00:36:07,980 --> 00:36:10,219 So you can grow a forest. 499 00:36:10,220 --> 00:36:12,619 It increases the conductive surface area 500 00:36:12,620 --> 00:36:16,619 and makes them very useful for electronic applications. 501 00:36:19,900 --> 00:36:23,899 The potential applications for this stuff are vast. 502 00:36:24,140 --> 00:36:28,139 Its conductivity and lightness will mean that it will replace copper, 503 00:36:28,340 --> 00:36:31,139 and it could carry several hundred times the current. 504 00:36:31,140 --> 00:36:34,739 Because it's the strongest material known to man, 505 00:36:34,740 --> 00:36:38,739 people are even talking about building an elevator into space with it. 506 00:36:42,420 --> 00:36:45,259 The space elevator is an idea 507 00:36:45,260 --> 00:36:47,499 that's been around for over 100 years, 508 00:36:47,500 --> 00:36:51,499 but now it's left the pages of Jules Verne and become a real possibility. 509 00:37:03,740 --> 00:37:07,739 The aim would be to create a cable to link Earth to a space satellite. 510 00:37:08,580 --> 00:37:12,579 An elevator would then run up the cable, like a train on rails. 511 00:37:12,820 --> 00:37:15,859 It would extend 22,000 miles into space 512 00:37:15,860 --> 00:37:19,859 and a further 40,000 to a counterbalance to stabilise the structure. 513 00:37:20,260 --> 00:37:24,259 But with production at 12 miles a day, there's a long way to go. 514 00:37:31,300 --> 00:37:35,299 Imagine one day you could build a giant solar power station in space, 515 00:37:36,700 --> 00:37:40,699 and think how much clean energy you could send back to Earth. 516 00:37:44,100 --> 00:37:48,099 HAWKING: In the last 60 or 70 years, we have learned much about 517 00:37:48,180 --> 00:37:52,179 the extraordinary workings of the universe around us, and within us. 518 00:37:57,300 --> 00:38:01,299 But there are still great essential mysteries to be solved, 519 00:38:01,940 --> 00:38:03,819 questions we ask ourselves 520 00:38:03,820 --> 00:38:07,819 about how the universe works and the future of mankind. 521 00:38:12,420 --> 00:38:15,539 In a few days, I'm planning to visit Stephen Hawking, 522 00:38:15,540 --> 00:38:19,539 to ask him what he thinks of some of the big puzzles that face us all, 523 00:38:20,660 --> 00:38:24,659 and find out what he'd like to ask me. 524 00:38:30,340 --> 00:38:33,939 For me, the essence of what scientists do is not maths or experiments, 525 00:38:33,940 --> 00:38:37,659 abstract thought or even applying for research funding, 526 00:38:37,660 --> 00:38:41,299 but asking questions. 527 00:38:41,300 --> 00:38:44,899 Newton wanted to know why things fell to the ground. 528 00:38:44,900 --> 00:38:48,899 Darwin, why animals were different in different places. 529 00:38:50,620 --> 00:38:53,299 I'm on my way to talk to Stephen Hawking 530 00:38:53,300 --> 00:38:56,859 about some of the questions we are both still asking. 531 00:38:56,860 --> 00:39:00,859 I want to ask him his views on evolution. As a physicist, 532 00:39:00,940 --> 00:39:04,939 does he think that the origin of life on Earth is just a happy coincidence? 533 00:39:06,620 --> 00:39:08,699 The existence of the Earth, 534 00:39:08,700 --> 00:39:12,699 and the properties that made it possible for biological life to develop, 535 00:39:14,180 --> 00:39:18,179 depend on a very fine balance between the so-called constants of nature. 536 00:39:19,820 --> 00:39:23,019 If they were more than slightly different, 537 00:39:23,020 --> 00:39:25,939 either planets like the Earth would not occur, 538 00:39:25,940 --> 00:39:29,939 or the chemical processes necessary for life would not take place. 539 00:39:31,900 --> 00:39:35,339 One might take this as evidence for a divine creator, 540 00:39:35,340 --> 00:39:39,339 but an alternative explanation is what is known as the multiverse. 541 00:39:40,380 --> 00:39:44,379 The idea is that there are many possible universes. 542 00:39:44,740 --> 00:39:48,739 Only in the small number of universes that are suitable 543 00:39:48,820 --> 00:39:51,099 will intelligent beings develop, 544 00:39:51,100 --> 00:39:55,099 and be able to ask the question, "Why is the universe so carefully designed?" 545 00:40:00,700 --> 00:40:03,659 DAWKINS: What happened before the Big Bang? 546 00:40:03,660 --> 00:40:07,659 What happened before the origin of space and time? 547 00:40:11,300 --> 00:40:15,299 HAWKING: In Newton's theory, time was separate from space, 548 00:40:15,340 --> 00:40:19,339 and ran from the infinite past to the infinite future. 549 00:40:20,060 --> 00:40:21,619 However, Newton's theory 550 00:40:21,620 --> 00:40:25,619 was superseded by Einstein's general theory of relativity. 551 00:40:26,980 --> 00:40:30,979 This allowed the beginning of the universe to be like the South Pole, 552 00:40:32,420 --> 00:40:35,899 with degrees of latitude playing the role of time. 553 00:40:35,900 --> 00:40:39,099 Asking for a time before the beginning 554 00:40:39,100 --> 00:40:43,099 would be like asking for a point south of the South Pole. 555 00:40:51,180 --> 00:40:55,179 Can one assume that insects and bacteria will survive us 556 00:40:55,540 --> 00:40:59,539 if our so-called intelligence leads us to destroy ourselves 557 00:41:00,060 --> 00:41:03,819 by nuclear war or other disasters? 558 00:41:03,820 --> 00:41:06,739 Yes, I think you've got an excellent point. 559 00:41:06,740 --> 00:41:10,099 We happen to survive by our intelligence 560 00:41:10,100 --> 00:41:12,859 and so we think that's the way you should survive. 561 00:41:12,860 --> 00:41:15,899 But from a bird's point of view, say a swift, 562 00:41:15,900 --> 00:41:19,379 they would think that flying is the way you survive. 563 00:41:19,380 --> 00:41:22,979 Eyes are said to have evolved some 40 times, independently. 564 00:41:22,980 --> 00:41:26,099 Flight has evolved four times independently. 565 00:41:26,100 --> 00:41:30,099 But it looks as though intelligence, at least verbal intelligence of our kind, 566 00:41:30,740 --> 00:41:32,779 has only evolved once, 567 00:41:32,780 --> 00:41:36,659 and so that might suggest that it's a pretty esoteric way of surviving. 568 00:41:36,660 --> 00:41:38,819 It seems to work very well for us, of course, 569 00:41:38,820 --> 00:41:42,259 and we're doing very well, we're overpopulating the planet with it, 570 00:41:42,260 --> 00:41:46,099 but if we go too far with it and destroy ourselves and destroy much of life, 571 00:41:46,100 --> 00:41:49,699 then of course you are right that other ways of survival will take over, 572 00:41:49,700 --> 00:41:52,539 bacteria prominent among them. 573 00:41:52,540 --> 00:41:54,859 HAWKING: One can't help asking. 574 00:41:54,860 --> 00:41:57,379 Why are you so obsessed with God? 575 00:41:57,380 --> 00:42:01,379 Well, I notice that you brought up the question of God and I didn't. 576 00:42:03,500 --> 00:42:05,579 When you ended A Brief History of Time 577 00:42:05,580 --> 00:42:07,819 with "for then we shall know the mind of God", 578 00:42:07,820 --> 00:42:11,019 I suspect that you were using God in a sort of Einsteinian sense, 579 00:42:11,020 --> 00:42:15,019 a euphemism for the mystery at the root of the universe, 580 00:42:15,460 --> 00:42:19,459 that which we don't understand, but most people use the word God for a person. 581 00:42:19,780 --> 00:42:22,779 God as an answer to scientific questions. 582 00:42:22,780 --> 00:42:26,099 Then I think it is scientifically pernicious 583 00:42:26,100 --> 00:42:29,739 because it distracts people away from the hard work 584 00:42:29,740 --> 00:42:32,299 of answering scientific questions. 585 00:42:32,300 --> 00:42:34,379 It's just too easy to say, "Oh, God did it, 586 00:42:34,380 --> 00:42:38,379 "therefore we don't need to answer the question." 587 00:42:39,260 --> 00:42:43,259 Looking to the future, do you think there will be scientific geniuses 588 00:42:43,300 --> 00:42:45,539 in a world of super-computers? 589 00:42:45,540 --> 00:42:49,539 Our picture of the universe has been transformed 590 00:42:49,900 --> 00:42:53,419 by brilliant individuals, like Newton and Einstein, 591 00:42:53,420 --> 00:42:57,419 who have made great leaps in the imagination. 592 00:42:57,780 --> 00:42:59,819 Computers cannot make such leaps, 593 00:42:59,820 --> 00:43:03,819 so I think there will be plenty more Newtons and Einsteins in the future. 594 00:43:06,340 --> 00:43:08,139 Thank you very much indeed. 595 00:43:08,140 --> 00:43:12,139 Thank you. 596 00:43:16,100 --> 00:43:17,899 In the not too distant future, 597 00:43:17,900 --> 00:43:20,539 there are certainly going to be major problems. 598 00:43:20,540 --> 00:43:24,379 Problems about climate change, 599 00:43:24,380 --> 00:43:28,379 problems about increasing density of population. 600 00:43:28,580 --> 00:43:32,579 There will be a problem, too, about power - how are we to generate power? 601 00:43:33,340 --> 00:43:36,299 Science will produce the answer. 602 00:43:36,300 --> 00:43:39,219 What the answer will be, I don't know, 603 00:43:39,220 --> 00:43:43,219 but I am perfectly certain that it is science that will find it for us. 604 00:43:49,340 --> 00:43:53,339 HAWKING: We began this story in the 17th century 605 00:43:53,540 --> 00:43:57,379 at a time of witchcraft and superstition, 606 00:43:57,380 --> 00:44:01,379 when Britain was just recovering from a bloody civil war. 607 00:44:03,060 --> 00:44:07,059 We've seen how a handful of men began by asking questions. 608 00:44:08,220 --> 00:44:12,219 What keeps the stars in the sky? 609 00:44:12,540 --> 00:44:15,979 What makes an apple fall? 610 00:44:15,980 --> 00:44:19,979 What invisible worlds exist on our skin and under our noses? 611 00:44:22,060 --> 00:44:26,059 Their determination and curiosity brought science into being. 612 00:44:30,860 --> 00:44:33,699 AL-KHALILI: In the 350 years since, 613 00:44:33,700 --> 00:44:37,699 British scientists have learnt to picture the enormity of the universe - 614 00:44:38,740 --> 00:44:42,419 and they've split the atom. 615 00:44:42,420 --> 00:44:46,419 DYSON: They discovered how to cross oceans and fly at supersonic speeds, 616 00:44:49,580 --> 00:44:53,579 how to power turbines and light up cities. 617 00:44:54,420 --> 00:44:57,739 DAWKINS: They've uncovered the greatest secrets of life 618 00:44:57,740 --> 00:45:00,499 and shown us just how astonishing the world is. 619 00:45:00,500 --> 00:45:03,619 WINSTON: Scientists have helped us live longer, 620 00:45:03,620 --> 00:45:07,619 healthier and more fulfilled lives than ever before. 621 00:45:09,540 --> 00:45:13,499 ATTENBOROUGH: Above all, these men have changed our world for ever. 622 00:45:13,500 --> 00:45:16,779 Indeed, they've made it what it is. 623 00:45:16,780 --> 00:45:20,579 DYSON: They were often awkward and contentious characters - 624 00:45:20,580 --> 00:45:24,579 people who kept on asking questions and didn't settle for second-rate answers. 625 00:45:25,620 --> 00:45:29,619 AL-KHALILI: Their stories explain why science is so important to us. 626 00:45:33,220 --> 00:45:36,219 SYKES: You don't have to be the cleverest kid in class 627 00:45:36,220 --> 00:45:40,219 or go to a posh school to become a great scientist. 628 00:45:40,820 --> 00:45:44,739 ATTENBOROUGH: What is clear is that we need more men and women 629 00:45:44,740 --> 00:45:48,019 like them in the future, not fewer. 630 00:45:48,020 --> 00:45:52,019 HAWKING: We hope that some of you watching now will take up this challenge 631 00:45:53,340 --> 00:45:57,339 and continue to ask the important questions.