1 00:01:22,400 --> 00:01:25,540 Welcome to an adventure of the mind! 2 00:01:25,540 --> 00:01:32,080 It begins by looking ahead to the sights and sounds of the mechanical universe. 3 00:01:33,780 --> 00:01:39,260 There are certain human activities that the mind associates with a particular place. 4 00:01:39,260 --> 00:01:42,620 Because it's somehow more special, more elegant there. 5 00:01:42,620 --> 00:01:46,060 For example: I'm not inclined to gamble. 6 00:01:46,060 --> 00:01:50,520 But if I wanted to, I wouldn't go and play poker in some sleazy back room. 7 00:01:50,520 --> 00:01:52,700 I would take the Concord to Monte Carlo, 8 00:01:52,700 --> 00:01:56,340 put on my tuxedo, and play Roulette in the casino. 9 00:01:56,340 --> 00:02:00,740 In the same way, when I think of tennis, I think of Wimbledon. 10 00:02:00,740 --> 00:02:03,320 For horse racing, it's the Kentucky Derby. 11 00:02:03,320 --> 00:02:05,800 For opera, it's La Scala. 12 00:02:05,800 --> 00:02:10,460 And for physics, if you want to study physics, the place is... Caltech. 13 00:02:12,340 --> 00:02:15,620 That's what we're here for. Let's get started. 14 00:02:20,880 --> 00:02:24,820 There is a branch of science, cosmology it's called, 15 00:02:24,820 --> 00:02:30,880 that concerns itself with the past, present and future of the universe as a whole. 16 00:02:34,120 --> 00:02:40,540 How did that universe begin? How has it evolved? And where is it going? 17 00:02:43,540 --> 00:02:50,760 There is another branch of science in the realm of physics, to be exact, which is called mechanics. 18 00:02:50,760 --> 00:02:58,280 The science of mechanics concerns itself with something not quite as philosophical perhaps, but no less profound. 19 00:03:02,280 --> 00:03:07,700 However it started, and wherever it's going, how does it all work? 20 00:03:16,820 --> 00:03:21,200 From the smallest particle to the largest cluster of galaxies, 21 00:03:21,200 --> 00:03:23,760 what keeps it all going? 22 00:03:23,760 --> 00:03:28,200 Whether it's speeding up, slowing down, 23 00:03:28,200 --> 00:03:33,220 changing direction, or cruising straight ahead, 24 00:03:33,220 --> 00:03:37,220 Why does it all behave the way it does? 25 00:03:38,500 --> 00:03:45,740 Whether it's a solid, a liquid, or a gas, or an enigmatic unseen force, 26 00:03:45,740 --> 00:03:49,940 Just how does it all interact? And why? 27 00:03:51,240 --> 00:03:55,400 All of these questions, from the simplest to the most profound 28 00:03:55,400 --> 00:03:58,300 are by no means later arrivals. 29 00:03:58,300 --> 00:04:03,640 In one form or another, they've been around as long as there have been people to ask them. 30 00:04:07,860 --> 00:04:13,550 Even the earliest human inhabitants of this planet must have looked up at the sky 31 00:04:13,550 --> 00:04:19,320 and across the landscape and asked: How does it all work? 32 00:04:19,320 --> 00:04:26,060 And without even knowing it, they had taken the first tentative steps towards discovering 33 00:04:26,060 --> 00:04:30,440 and understanding the mechanical universe. 34 00:04:33,320 --> 00:04:40,060 If there is a key to understanding the mechanical universe, it can be found in the realm of mathematics. 35 00:04:40,060 --> 00:04:47,740 And among earliest civilizations, there were no greater mathematicians than the Ancient Greeks. 36 00:04:47,740 --> 00:04:52,860 The work of Greek mathematicians added immeasurably to the advanced method of science. 37 00:04:52,860 --> 00:04:55,700 In the area of circles, for example, 38 00:04:55,700 --> 00:04:57,940 they work to the point of exhaustion, 39 00:04:57,940 --> 00:05:02,900 which is precisely what it took to find the number π (pi). 40 00:05:02,900 --> 00:05:09,880 But despite, or maybe because of, such brilliant discoveries, the Greeks fell behind. 41 00:05:09,880 --> 00:05:16,800 Once the golden age was over, they placed the lower value on the questions than on the answers. 42 00:05:16,800 --> 00:05:21,020 So, with too few questions the world put on Aristotle mechanics, 43 00:05:22,340 --> 00:05:27,400 with Plato's ideas, and eventually Ptolemy's solar system, 44 00:05:27,400 --> 00:05:34,460 it was the planets orbit the Earth uniformly, circles on perfect circles, which held aloft by conventional wisdom. 45 00:05:34,460 --> 00:05:40,100 Answers instead of questions, that went almost unchallenged well until the Renaissance. 46 00:05:41,060 --> 00:05:44,040 The intellectual direction of Western civilization 47 00:05:44,040 --> 00:05:49,420 had fallen into line behind the endless circular argument of the Platonic ideal 48 00:05:49,420 --> 00:05:54,580 The question isn't really WHY, unless it's why tamper with perfection? 49 00:05:54,580 --> 00:05:57,100 The question is HOW? 50 00:05:57,440 --> 00:06:03,420 How, 1500 years after Ptolemy, was the perfect circle broken? 51 00:06:03,420 --> 00:06:07,100 And, in what must seemed another contradiction of logic, 52 00:06:07,100 --> 00:06:10,040 How did an order of the New World take shape 53 00:06:10,040 --> 00:06:13,320 and the principle of scientific revolution? 54 00:06:13,320 --> 00:06:17,920 It began when an extremely curious Polish monk, Nikolaus Copernicus, 55 00:06:17,920 --> 00:06:23,360 looked toward the stars, and saw things in a different light. 56 00:06:23,360 --> 00:06:31,320 Among other things in the Copernicus's solar system, the Earth orbits the sun, rather than the other way around. 57 00:06:31,320 --> 00:06:34,920 Why did Copernicus see the universe this way? 58 00:06:34,920 --> 00:06:42,240 and from a scientific point of view, how did such a vision make him the world's first revolutionary? 59 00:06:42,240 --> 00:06:49,320 An intellectual bridge that is spanned thousands of years, wave precariously in the winds of change. 60 00:06:50,260 --> 00:06:55,900 Pillars of an age-old academic community, we'll be set with threatening questions. 61 00:07:00,160 --> 00:07:06,740 No one was better equipped to fill the intellectual void than Galileo Galilei. 62 00:07:06,740 --> 00:07:11,740 Though Aristotelian thinking still ruled the world of the Italian Renaissance, 63 00:07:11,740 --> 00:07:14,980 Galileo was an exception to the rule. 64 00:07:14,980 --> 00:07:19,100 He was a Copernican, with the courage of his convictions. 65 00:07:19,100 --> 00:07:24,460 In other words, he had the right idea at the wrong time. 66 00:07:24,460 --> 00:07:29,420 Later, an army arose in defense of the status quo. 67 00:07:29,420 --> 00:07:37,620 But if the Earth really spins, why does a ball drop from a tower in Pisa, for example, land directly below? 68 00:07:37,620 --> 00:07:40,640 why not in the next city state? 69 00:07:40,640 --> 00:07:46,380 For a change, the answers were more dangerous than the questions. 70 00:07:46,380 --> 00:07:51,640 The Church, which considered him both a threat to Rome and then a front to common sense, 71 00:07:51,640 --> 00:07:54,780 warned him to leave things under proper places. 72 00:07:54,780 --> 00:07:57,840 Nonetheless, in practice and theory, 73 00:07:57,840 --> 00:08:02,720 Galileo spoke the truth and proved what seemed to be the impossible. 74 00:08:02,720 --> 00:08:05,500 And when all was said and done, 75 00:08:05,500 --> 00:08:11,160 Here in my left hand I have a feather, in my right hand a hammer 76 00:08:11,160 --> 00:08:16,680 and I'll drop the two down here and hopefully, they will hit the ground at the same time. 77 00:08:17,860 --> 00:08:24,760 How about that? Have to admit Galileo was correct and is finally... 78 00:08:24,760 --> 00:08:29,580 Galileo's findings are not only correct, 79 00:08:29,580 --> 00:08:35,680 they come down to history as an amazing example of the scientific imagination at work. 80 00:08:35,680 --> 00:08:40,320 With his brilliant mind set on explaining the universe in scientific terms, 81 00:08:40,320 --> 00:08:45,900 Galileo's experiments led him to discover the law of inertia. 82 00:08:46,900 --> 00:08:53,290 With uncanny physical insight, he accurately envisioned the parabolic path of projectiles 83 00:08:53,290 --> 00:08:56,660 as well as the law of falling bodies. 84 00:08:56,660 --> 00:09:00,520 Even today, when they come right down to it, 85 00:09:00,520 --> 00:09:06,400 the questions behind these experiments are as challenging as they were 3 centuries ago. 86 00:09:07,380 --> 00:09:11,080 How did Galileo calculate a projectile's path? 87 00:09:11,080 --> 00:09:17,000 And by doing so, how did he begin to propel mathematics deeply into the future? 88 00:09:18,860 --> 00:09:21,920 In the days when seeing truly was believing, 89 00:09:21,920 --> 00:09:26,860 how did he disprove the obvious perception about falling objects? 90 00:09:26,860 --> 00:09:31,200 How can a hammer and a feather land at the same moment? 91 00:09:31,200 --> 00:09:35,480 And does Galileo himself fell from grace since 1633? 92 00:09:35,480 --> 00:09:41,040 Why was the whole business of the universe a trial to everyone concerned? 93 00:09:43,420 --> 00:09:48,720 About the same time, every day was something of a trial to the wandering mathematician: 94 00:09:48,720 --> 00:09:50,820 Johannes Kepler. 95 00:09:50,820 --> 00:09:56,180 To a man in almost constant flight for his life, a life of illness and poverty, 96 00:09:56,180 --> 00:10:02,420 the loss of love and loved ones, which hunts the even meaner spirits of the associates. 97 00:10:02,420 --> 00:10:05,680 Simple existence was something of a challenge. 98 00:10:07,920 --> 00:10:13,220 Surely, no man ever sacrificed more to grasp the scientific truth. 99 00:10:13,220 --> 00:10:18,220 But on the other hand, no man's discoveries ever proved more rewarding 100 00:10:18,220 --> 00:10:20,360 than Kepler's laws, 101 00:10:22,040 --> 00:10:24,260 the law of the ellipses, 102 00:10:26,120 --> 00:10:28,420 the law of equal areas, 103 00:10:29,480 --> 00:10:34,200 and Kepler's third law of planetary motion, the law of harmony. 104 00:10:35,500 --> 00:10:38,780 With his laws of planetary motion as the key, 105 00:10:38,780 --> 00:10:42,700 Kepler entered the secret chamber of the cosmos. 106 00:10:46,180 --> 00:10:51,080 And yet, by explaining how, rather than why, the solar system works, 107 00:10:51,080 --> 00:10:56,040 he was destined to remain on the threshold of the mechanical universe. 108 00:10:56,040 --> 00:10:58,960 It was time for someone else to come along, 109 00:10:58,960 --> 00:11:01,320 and take the final step. 110 00:11:02,400 --> 00:11:05,920 On this very path, which led directly to the moon, 111 00:11:05,920 --> 00:11:07,920 along came Isaac Newton. 112 00:11:07,920 --> 00:11:11,020 with some crucial questions of his own. 113 00:11:11,020 --> 00:11:13,680 Why does an apple fall? 114 00:11:13,680 --> 00:11:17,540 Since an apple falls, why not the moon? 115 00:11:17,540 --> 00:11:21,060 If an apple and the moon fall for the same reason, 116 00:11:21,060 --> 00:11:25,800 why doesn't the moon, like the apple, crash into the Earth? 117 00:11:29,100 --> 00:11:32,460 With such questions, the questions of a lifetime 118 00:11:32,460 --> 00:11:36,220 Newton, rather calmly sat down, had piece by piece, 119 00:11:36,220 --> 00:11:41,740 destroyed beyond repair the age-old machinery of the Aristotelian universe. 120 00:11:41,740 --> 00:11:45,160 And then, with answers that were equally astounding, 121 00:11:45,160 --> 00:11:50,320 he created something to take his place: the mechanical universe. 122 00:11:52,920 --> 00:11:57,280 The mechanical universe, a predictable, orderly universe, 123 00:11:57,280 --> 00:12:00,720 obeying precise mathematical laws. 124 00:12:01,720 --> 00:12:08,420 And with the laws of motion, the ability to take on almost any physical challenge 125 00:12:08,420 --> 00:12:12,940 With his laws of motion, not unlike David confronting Goliath 126 00:12:12,940 --> 00:12:17,020 Isaac Newton took on the great issues of mechanics. 127 00:12:17,020 --> 00:12:20,340 Armed with his keen mastery of forces, 128 00:12:20,340 --> 00:12:23,420 a precise knowledge of trajectories, 129 00:12:26,000 --> 00:12:29,000 and the universal law of gravitation 130 00:12:32,320 --> 00:12:37,040 Newton mastered more than any human being before him. 131 00:12:37,040 --> 00:12:43,220 And for that, he deserved serious attention, and considerable fanfare. 132 00:12:44,100 --> 00:12:46,940 Nonetheless, in science, 133 00:12:46,940 --> 00:12:49,700 answers are part of the past 134 00:12:49,700 --> 00:12:53,710 the future belongs to the questions that science raises. 135 00:12:55,360 --> 00:13:01,320 Which means that even Newton's laws were only a beginning in the right direction. 136 00:13:01,320 --> 00:13:08,280 For example, in modern times, a projector can be guided with mathematical precision 137 00:13:08,280 --> 00:13:10,460 How is that done? 138 00:13:12,280 --> 00:13:16,300 Part of the answer is the instrument called the gyroscope 139 00:13:16,300 --> 00:13:18,300 How does it work? 140 00:13:18,300 --> 00:13:21,320 And in the all encompassing mechanical universe, 141 00:13:21,320 --> 00:13:25,980 why is even a bicycle wheel a kind of gyroscope? 142 00:13:25,980 --> 00:13:29,360 Angular momentum is the key to the answer. 143 00:13:29,360 --> 00:13:31,680 But what is angular momentum? 144 00:13:31,680 --> 00:13:36,000 And why does it turn out to be so vital throughout the universe? 145 00:13:36,000 --> 00:13:39,420 From the cutting-edge of the most distant galaxy 146 00:13:39,420 --> 00:13:42,180 to whirlpools and the family bath, 147 00:13:42,180 --> 00:13:46,460 angular momentum moves in all the best circles. 148 00:13:48,460 --> 00:13:53,960 And among other things, moving in circles is the key to keeping perfect time. 149 00:13:53,960 --> 00:13:58,760 Through things govern as steadily as today's mechanistic concern with time. 150 00:13:59,920 --> 00:14:08,280 However, while people now have more time on their hands, the preoccupation with it is hardly a reasoned phenomenon. 151 00:14:09,780 --> 00:14:15,200 What is comparatively reasoned, however, is the phenomenon of accurate time. 152 00:14:15,200 --> 00:14:21,140 It came about gradually, day in and day out, for 4000 years. 153 00:14:22,980 --> 00:14:27,740 It finally arrived, with an understanding of harmonic motion. 154 00:14:27,740 --> 00:14:30,440 What is harmonic motion? 155 00:14:30,440 --> 00:14:35,620 And when it comes right down and up to it, how does harmonic motion really work? 156 00:14:39,300 --> 00:14:45,660 And going full circle in the mechanical universe, how is it related to circular motion? 157 00:14:47,140 --> 00:14:51,240 The answer isn't as mysterious as it may seem at first perception. 158 00:14:51,240 --> 00:14:54,940 And there's no reason to approach it in a roundabout fashion. 159 00:14:54,940 --> 00:14:57,560 However, sometimes it helps. 160 00:14:59,660 --> 00:15:02,760 All it takes is a little differential calculus. 161 00:15:03,940 --> 00:15:08,980 While Isaac Newton's calculus goes far and wide throughout the mechanical universe, 162 00:15:08,980 --> 00:15:13,140 The scope of his generosity was considerably more narrow. 163 00:15:14,040 --> 00:15:20,500 Then Wilhelm Gottfried von Leibniz strode the European landscape with a supreme confidence, 164 00:15:20,500 --> 00:15:23,680 and a number of good reasons for it. 165 00:15:23,680 --> 00:15:26,560 As a German diplomat in mathematician, 166 00:15:26,560 --> 00:15:33,080 Leibniz was so successful that Voltaire characterized him as the epitome of optimism. 167 00:15:33,880 --> 00:15:38,680 Worldly, outgoing, quite a fellow with the ladies, 168 00:15:38,680 --> 00:15:41,560 Leibniz had nothing in common with Newton 169 00:15:41,560 --> 00:15:45,040 except the discovery of the calculus. 170 00:15:45,040 --> 00:15:48,720 There is plenty of room on Newton's plate for a little kindness 171 00:15:48,720 --> 00:15:52,340 After all, he'd created the law of motion, 172 00:15:52,340 --> 00:15:56,400 the law of universal gravitation, the reflector telescope, 173 00:15:56,400 --> 00:15:59,780 a theoretical explanation for light and color. 174 00:15:59,780 --> 00:16:05,480 The menu of his unmatched accomplishments was extensive, to say the least. 175 00:16:05,480 --> 00:16:13,900 And yet, despite so much intelligence, Newton permitted, if not encouraged, a bitter controversy with Leibniz. 176 00:16:17,080 --> 00:16:21,540 This episode, only one of the emotional dramas in the mechanical universe 177 00:16:21,540 --> 00:16:23,860 threatened the reputation of one man 178 00:16:23,860 --> 00:16:25,980 and the sanity of another. 179 00:16:25,980 --> 00:16:32,300 But it will also illustrate one of the curious paradoxes that lurk within the human heart of science. 180 00:16:32,300 --> 00:16:36,860 For example, while the scientist isn't always rational, 181 00:16:36,860 --> 00:16:41,100 the scientific environment nearly always is. 182 00:16:41,100 --> 00:16:48,020 In fact, a physics laboratory is where nature rebuilds herself in the most rational terms. 183 00:16:48,020 --> 00:16:53,380 Compared to Newton, what does the modern scientist really do? 184 00:16:53,380 --> 00:16:58,700 Beyond the well-intention textbook definition, what's the method of science? 185 00:16:58,700 --> 00:17:04,500 And in the real world, how does the scientific method really work? 186 00:17:04,500 --> 00:17:08,900 Sometimes it begins with the small things 187 00:17:08,900 --> 00:17:11,160 the sturdy iron pot, 188 00:17:11,160 --> 00:17:13,220 a dash of discipline, 189 00:17:13,220 --> 00:17:17,780 a measure of creativity, 190 00:17:17,960 --> 00:17:21,420 and perhaps a touch of genius, 191 00:17:21,420 --> 00:17:24,430 and sometimes, although very rarely, 192 00:17:24,430 --> 00:17:28,960 the result is the significance of the value of the charge of the electron. 193 00:17:36,000 --> 00:17:38,160 Who was this physicist? 194 00:17:38,160 --> 00:17:43,640 And by what painstaking means did he become one of the more famous men in scientific history? 195 00:17:44,940 --> 00:17:49,080 Past, present and future 196 00:17:49,080 --> 00:17:53,660 Physicists are forever fascinated by the mysteries of nature. 197 00:17:53,660 --> 00:17:58,800 For example, the mysterious nature of light. 198 00:17:58,800 --> 00:18:03,080 Light, the very idea has been as hard to grasp 199 00:18:03,080 --> 00:18:07,080 as the almost incomprehensible vastness of the universe. 200 00:18:07,080 --> 00:18:10,080 And its speed has been even harder. 201 00:18:10,080 --> 00:18:13,400 Why does it have this specific value? 202 00:18:13,400 --> 00:18:16,640 Why is it called the fundamental constant? 203 00:18:16,640 --> 00:18:21,200 And precisely what is a fundamental constant of nature? 204 00:18:22,220 --> 00:18:28,040 Henry Cavendish knew the answer when he measured Newton's universal gravitational constant 205 00:18:28,040 --> 00:18:30,060 In the process of finding it, 206 00:18:30,060 --> 00:18:36,400 Cavendish not only weighed the expanding British Empire, he weighed the entire planet. 207 00:18:38,080 --> 00:18:40,800 How in the world did he do that? 208 00:18:40,800 --> 00:18:44,320 From not by hanging out in the pool 209 00:18:51,540 --> 00:18:55,400 These men lived by laws that if not exactly legal 210 00:18:55,400 --> 00:19:00,160 are nonetheless well within the laws of the classical mechanics. 211 00:19:00,160 --> 00:19:04,760 Of course, not every man here fully appreciates that fact 212 00:19:08,600 --> 00:19:12,640 Most walked down chalky narrow stairs to shoot his stick 213 00:19:12,640 --> 00:19:16,520 or to profit from the experience by some other means 214 00:19:16,520 --> 00:19:21,860 But odds are, when certain laws of physics are applied just right 215 00:19:23,540 --> 00:19:27,540 every man here fully appreciates the effects. 216 00:19:31,380 --> 00:19:35,400 The effects depend on the law of conservation of momentum. 217 00:19:35,400 --> 00:19:41,000 And like the game of billiards, it happened to originate in France. 218 00:19:41,000 --> 00:19:48,760 In the early 17th century, René Descartes grew up to love mathematics as the workings of God. 219 00:19:48,760 --> 00:19:54,680 And as a philosopher, he saw an explanation for all worldly phenomena. 220 00:19:57,040 --> 00:20:01,900 In the process, Descartes not only conceived the conservation of momentum, 221 00:20:01,900 --> 00:20:05,680 he discovered analytic geometry. 222 00:20:05,680 --> 00:20:08,880 With that discovery, he changed forever 223 00:20:08,880 --> 00:20:12,440 the terrain of mathematics. 224 00:20:12,440 --> 00:20:19,220 How, by one vehicle or another, the Greek scientific explorers approach unknown terrain. 225 00:20:22,480 --> 00:20:25,060 And when something has been discovered already, 226 00:20:25,060 --> 00:20:28,780 how can someone else sail right in and claim the credit? 227 00:20:31,180 --> 00:20:37,140 Whatever the science, from electricity to mechanics, 228 00:20:41,840 --> 00:20:45,440 Credit sometimes goes not to the first to make a great discovery 229 00:20:45,440 --> 00:20:47,680 but to the last. 230 00:20:47,680 --> 00:20:51,920 Surely, this was true in the case of James Prescott Joule. 231 00:20:51,920 --> 00:20:56,640 Though is far from the first to explore the realm of energy conservation, 232 00:20:56,640 --> 00:21:02,100 he might've been the 8th or 9th scientist to come across the law of conservation of energy. 233 00:21:02,100 --> 00:21:08,540 But like Columbus, Joule got the credit for discovery why. 234 00:21:08,540 --> 00:21:13,180 And in the greater scheme of things, why does it really matter? 235 00:21:13,180 --> 00:21:18,500 In the storehouse of the cosmos, the shelves are as amply stocked with the energy today. 236 00:21:18,500 --> 00:21:22,600 As they were the morning the universe opened for business. 237 00:21:22,600 --> 00:21:25,920 On the other hand, if energy is never lost, 238 00:21:25,920 --> 00:21:28,760 why do muscles get tired? 239 00:21:30,080 --> 00:21:33,580 And why do masses fall? 240 00:21:33,580 --> 00:21:36,940 Mechanical energy, like exercise and general, 241 00:21:36,940 --> 00:21:40,200 has a lot to do with speed and position. 242 00:21:43,760 --> 00:21:46,840 For a different perspective on changing positions, 243 00:21:46,840 --> 00:21:54,120 Catch the drift of the good ship Irish Coffee, a challenge if there ever was one in the mechanical universe. 244 00:21:54,120 --> 00:21:56,300 Sophisticated electronics, 245 00:21:56,300 --> 00:21:58,960 state-of-the-art tracking devices, 246 00:21:58,960 --> 00:22:01,620 personnel beyond compare. 247 00:22:01,620 --> 00:22:05,500 These are the resources of the United States Coast Guard. 248 00:22:05,500 --> 00:22:10,920 Also, behind the scenes, there are the tools of vector analysis. 249 00:22:10,920 --> 00:22:13,360 In a crisis or a classroom, 250 00:22:13,360 --> 00:22:17,160 how can vector mathematics go to the rescue? 251 00:22:28,200 --> 00:22:33,440 In the series world of science, vector mathematics can accomplish very much. 252 00:22:33,440 --> 00:22:37,200 So the question is not whether it can come to this rescue 253 00:22:37,200 --> 00:22:39,580 but whether it really should. 254 00:22:39,920 --> 00:22:43,540 Put it another way, is this music? 255 00:22:45,200 --> 00:22:47,300 Or is it memorex? 256 00:22:47,300 --> 00:22:50,720 In any case, a classic memorex commercial 257 00:22:50,720 --> 00:22:56,600 clearly illustrates both excellent reproductions and the physical phenomenon of resonance. 258 00:22:56,600 --> 00:22:58,260 What is resonance? 259 00:22:58,260 --> 00:23:02,540 How is many forms heard from throughout the mechanical universe? 260 00:23:02,540 --> 00:23:07,720 And why does a mere human voice, even one as powerful as Ella Fitzgerald's 261 00:23:07,720 --> 00:23:10,900 produce such shattering results? 262 00:23:11,980 --> 00:23:15,680 And in the even greater atmosphere of the mechanical universe, 263 00:23:15,680 --> 00:23:19,900 what are some other forms of sound and fury? 264 00:23:19,900 --> 00:23:22,000 This trio undertook a journey 265 00:23:22,000 --> 00:23:28,060 that surpassed every earthly explorers since the first primitive step to the unknown. 266 00:23:28,060 --> 00:23:31,780 That our destiny has been determined by engineers and scientists, 267 00:23:31,780 --> 00:23:35,860 technicians and visionaries, researchers and test pilots 268 00:23:35,860 --> 00:23:39,680 by the best laid plans and all the right stuff. 269 00:23:39,680 --> 00:23:41,720 The light the rocket itself 270 00:23:41,720 --> 00:23:44,500 a straightforward question arose: 271 00:23:44,500 --> 00:23:48,750 How was it possible to get from here to there? 272 00:23:48,750 --> 00:23:52,260 Historically speaking, rockets don't go anywhere 273 00:23:52,260 --> 00:23:55,700 without a pretty good plan behind them. 274 00:23:55,700 --> 00:24:01,740 And even today, they don't get very far without classical mechanics. 275 00:24:01,740 --> 00:24:04,840 Who are the space navigators? 276 00:24:04,840 --> 00:24:08,520 Beyond the everyday world, what do they seek? 277 00:24:08,520 --> 00:24:13,000 And often surprisingly, what do they find? 278 00:24:13,000 --> 00:24:15,100 From Johannes Kepler onward, 279 00:24:15,100 --> 00:24:20,160 celestial scientists calculate the motions of the solar system. 280 00:24:20,160 --> 00:24:25,340 But the miracle of the space say you're just making heaven passable, as well as possible. 281 00:24:25,340 --> 00:24:29,320 Well that might've been what the father of the classical mechanics dreamt of 282 00:24:29,320 --> 00:24:32,720 is what the space navigators do. 283 00:24:32,720 --> 00:24:37,180 In a sense, all scientists are navigators and explorers. 284 00:24:37,180 --> 00:24:43,240 The quest, in one way or another, has always been human destiny. 285 00:24:43,240 --> 00:24:47,800 The strategy has always had something to do with teaching and learning, 286 00:24:47,800 --> 00:24:52,620 with imagination and logic, with trial and error, 287 00:24:54,860 --> 00:24:57,900 with taking risks and going to the limit. 288 00:24:57,900 --> 00:25:01,380 Not only the strategy but the universe itself 289 00:25:01,380 --> 00:25:05,720 may turn out to be some sort of cosmic game. 290 00:25:08,100 --> 00:25:13,220 Over the years, the roster has included some very impressive players. 291 00:25:13,220 --> 00:25:15,440 Some played by the rules. 292 00:25:15,440 --> 00:25:18,080 And some made up their own. 293 00:25:18,080 --> 00:25:20,720 But all of them shared a common need: 294 00:25:20,720 --> 00:25:23,680 they HAD to play the game. 295 00:25:23,680 --> 00:25:27,920 It's been played for the highest stakes and for the longest time. 296 00:25:27,920 --> 00:25:32,420 And in a sense, the game will never be over. 297 00:25:32,420 --> 00:25:36,120 I think that our subject, classical mechanics 298 00:25:36,120 --> 00:25:41,260 is part of the most important discovery in history. 299 00:25:41,260 --> 00:25:42,860 Before it was made, 300 00:25:42,860 --> 00:25:46,860 our view of the universe was the one that we received from the Ancient Greeks 301 00:25:46,860 --> 00:25:51,020 merely in the worlds of Plato and Aristotle. 302 00:25:51,020 --> 00:25:56,640 In that view, the crystal spheres of the heavens were immutable, serene, 303 00:25:56,640 --> 00:25:59,300 eternal and perfect. 304 00:25:59,300 --> 00:26:04,200 Only down here, in this lowly Earth, was there confusion, 305 00:26:04,200 --> 00:26:08,140 decay, disorder and death. 306 00:26:08,140 --> 00:26:13,420 It was a view that was literally designed to push us in our places. 307 00:26:13,420 --> 00:26:17,840 But that place, the Earth, was at the center of the universe 308 00:26:17,840 --> 00:26:22,900 and we can easily imagine ourselves to be the purpose of creation. 309 00:26:22,900 --> 00:26:25,720 Then along came Copernicus, 310 00:26:25,720 --> 00:26:29,360 and Kepler, and Galileo, and Newton. 311 00:26:29,360 --> 00:26:36,380 And by the time they were done, we live on the speck of dust, in a forsaken galaxy, in a lost corner of the universe. 312 00:26:36,380 --> 00:26:38,160 No matter how lowly, 313 00:26:38,160 --> 00:26:42,420 Plato and Aristotle had tried to make us live in their wildest dreams. 314 00:26:42,420 --> 00:26:45,660 They think of doing that to us. 315 00:26:45,660 --> 00:26:48,380 Like today, it's not very different 316 00:26:48,380 --> 00:26:51,100 from what it was 2000 years ago. 317 00:26:51,100 --> 00:26:55,900 It is essential if human condition has not changed very much. 318 00:26:55,900 --> 00:26:59,520 But in that one thing it's changed forever... 319 00:26:59,520 --> 00:27:03,680 ...we've discovered our place in the universe. 320 00:27:03,680 --> 00:27:07,200 That's why the discovery is so important. 321 00:27:07,200 --> 00:27:11,660 Our job is to find out what that discovery was 322 00:27:11,660 --> 00:27:14,800 how it was made and by whom. 323 00:27:14,800 --> 00:27:19,680 And we'll begin with one of the most important discoveries by Galileo Galilei 324 00:27:19,680 --> 00:27:23,200 when we meet here next time! 325 00:27:24,240 --> 00:29:01,150 Subtitle created by Tran Nguyen Phuong Thanh - 2013.