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← My friend Richard Feynman | Leonard Susskind | TEDxCaltech

What's it like to be pals with a genius? Onstage at TEDxCaltech, physicist Leonard Susskind spins a few stories about his friendship with the legendary Richard Feynman, discussing his unconventional approach to problems both serious and ... less so.

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Showing Revision 7 created 11/17/2016 by TED Translators admin.

  1. I can't see the audience, and I hate that.
  2. How many great grandparents
    are there in the audience?
  3. Damn it, I can't see anything.
  4. You're probably wondering why I'm sitting.
  5. The answer is,
    because I'm a great-grandfather.
  6. Not a good grandfather,
    a great grandfather.
  7. (Laughter)
  8. And, as everybody knows,
  9. great grandparents get to do
    any damn thing they please.
  10. Including following my own
    grandfather's advice,
  11. which was, whenever you give a talk
    to a thousand people
  12. about Richard Feynman, sustain yourself.
  13. (Laughter)
  14. (Applause)
  15. This is an extremely slick operation
  16. and I'm not a slick man.
  17. I don't use these things.
  18. I decided when I was asked to do this
  19. that what I really wanted to talk about
    was my friend, Richard Feynman.
  20. I was one of the fortunate few
    that really did get to know him
  21. and enjoyed his presence.
  22. And I'm going to tell you
    about the Richard Feynman that I knew.
  23. I'm sure there are people here
    who could tell you
  24. about the Richard Feynman they knew,
  25. and it would probably be
    a different Richard Feynman.
  26. Richard Feynman was a very complex man.
  27. He was a man of many, many parts.
  28. He was, of course, foremost,
    a very, very, very great scientist.
  29. He was an actor. You saw him act.
  30. I also had the good fortune
    to be in those lectures,
  31. up in the balcony.
  32. They were fantastic.
  33. He was a philosopher.
  34. He was a drum player.
  35. He was a teacher par excellence.
  36. Richard Feynman was also a showman,
  37. an enormous showman.
  38. He was brash, irreverent.
  39. He was full of macho,
    a kind of macho one-upmanship.
  40. He loved intellectual battle.
  41. He had a gargantuan ego.
  42. But the man had, somehow,
  43. a lot of room at the bottom.
  44. And what I mean by that
    is a lot of room, in my case --
  45. I can't speak for anybody else,
    but in my case --
  46. a lot of room for another big ego.
  47. Well, not as big as his,
  48. but fairly big.
  49. I always felt good with Dick Feynman.
  50. It was always fun to be with him.
  51. He always made me feel smart.
  52. How can somebody like that
    make you feel smart?
  53. Somehow he did.
  54. He made me feel smart.
    He made me feel he was smart.
  55. He made me feel we were both smart,
  56. and the two of us could solve
    any problem whatever.
  57. And in fact, we did sometimes
    do physics together.
  58. We never published a paper together,
  59. but we did have a lot of fun.
  60. He loved to win,
  61. win these little macho games
    we would sometimes play.
  62. And he didn't only play them with me,
    but with all sorts of people.
  63. He would almost always win.
  64. But when he didn't win, when he lost,
  65. he would laugh and seem
    to have just as much fun
  66. as if he had won.
  67. I remember once he told me a story
  68. about a joke the students played on him.
  69. I think it was for his birthday --
  70. they took him for lunch
  71. to a sandwich place in Pasadena.
  72. It may still exist; I don't know.
  73. Celebrity sandwiches was their thing.
  74. You could get a Marilyn Monroe sandwich.
  75. You could get a Humphrey Bogart sandwich.
  76. The students went there in advance,
  77. and arranged that they'd all order
    Feynman sandwiches.
  78. One after another, they came in
    and ordered Feynman sandwiches.
  79. Feynman loved this story.
  80. He told me this story,
    and he was really happy and laughing.
  81. When he finished the story, I said to him,
  82. "Dick, I wonder what
    would be the difference
  83. between a Feynman sandwich
    and a Susskind sandwich."
  84. And without skipping a beat at all,
  85. he said, "Well, they'd be about the same.
  86. The only difference is a Susskind
    sandwich would have a lot more ham."
  87. "Ham" as in bad actor.
  88. (Laughter)
  89. Well, I happened to have been
    very quick that day,
  90. and I said, "Yeah,
    but a lot less baloney."
  91. (Laughter)
  92. (Applause)
  93. The truth of the matter
  94. is that a Feynman sandwich
    had a load of ham,
  95. but absolutely no baloney.
  96. What Feynman hated worse
    than anything else
  97. was intellectual pretense --
  98. phoniness,
  99. false sophistication, jargon.
  100. I remember sometime during the mid-'80s,
  101. Dick and I and Sidney Coleman
    would meet a couple of times
  102. up in San Francisco --
    at some very rich guy's house --
  103. up in San Francisco for dinner.
  104. And the last time the rich guy invited us,
  105. he also invited a couple of philosophers.
  106. These guys were philosophers of mind.
  107. Their specialty was the philosophy
    of consciousness.
  108. And they were full of all kinds of jargon.
  109. I'm trying to remember the words --
  110. "monism," "dualism,"
    categories all over the place.
  111. I didn't know what those meant, neither
    did Dick or Sydney, for that matter.
  112. Sydney, who was better educated
    than most of us.
  113. And what did we talk about?
  114. Well, what do you talk about
    when you talk about minds?
  115. There's one obvious thing to talk about:
  116. Can a machine become a mind?
  117. Can you build a machine
  118. that thinks like a human being
    that is conscious?
  119. We sat around and talked about this --
    we of course never resolved it.
  120. But the trouble with the philosophers
  121. is that they were philosophizing
  122. when they should have been
    science-ophizing.
  123. It's a scientific question, after all.
  124. And this was a very, very
    dangerous thing to do
  125. around Dick Feynman.
  126. (Laughter)
  127. Feynman let them have it --
    both barrels, right between the eyes.
  128. It was brutal; it was funny --
    ooh, it was funny.
  129. But it was really brutal.
  130. He really popped their balloon.
  131. But the amazing thing was --
    Feynman had to leave a little early;
  132. he wasn't feeling too well,
    so he left a little bit early.
  133. And Sidney and I were left there
    with the two philosophers.
  134. And the amazing thing
    is these guys were flying.
  135. They were so happy.
  136. They had met the great man;
  137. they had been instructed by the great man;
  138. they had an enormous amount of fun
  139. having their faces shoved in the mud ...
  140. And it was something special.
  141. I realized there was something
    just extraordinary about Feynman,
  142. even when he did what he did.
  143. So yes - he did not like
    intellectual pretense.
  144. Dick -- he was my friend;
    I did call him Dick --
  145. Dick and I had a little bit of a rapport.
  146. I think it may have been a special
    rapport that he and I had.
  147. We liked each other;
    we liked the same kind of things.
  148. I also like the intellectual macho games.
  149. Sometimes I would win,
    mostly he would win,
  150. but we both enjoyed them.
  151. And Dick became convinced at some point
  152. that he and I had
    some kind of similarity of personality.
  153. I don't think he was right.
  154. I think the only point
    of similarity between us
  155. is we both like to talk about ourselves.
  156. But he was convinced of this.
  157. And the man was incredibly curious.
  158. And he wanted to understand
    what it was and why it was
  159. that there was this funny connection.
  160. And one day, we were walking.
  161. We were in France, in Les Houches.
  162. We were up in the mountains, 1976.
    Up in the mountains.
  163. And Feynman said to me, "Leonardo ..."
  164. The reason he called me "Leonardo"
    is because we were in Europe,
  165. and he was practicing his French.
  166. (Laughter)
  167. And he said, "Leonardo,
  168. were you closer to your mother
    or your father when you were a kid?"
  169. I said, "Well, my real hero was my father.
  170. He was a working man,
  171. had a fifth-grade education.
  172. He was a master mechanic,
    and he taught me how to use tools.
  173. He taught me all sorts of things
    about mechanical things.
  174. He even taught me the Pythagorean theorem.
  175. He didn't call it the hypotenuse,
  176. he called it the shortcut distance."
  177. And Feynman's eyes just opened up.
  178. He went off like a lightbulb.
  179. And he said that he had had
  180. basically exactly the same
    relationship with his father.
  181. In fact, he had been convinced at one time
  182. that to be a good physicist,
  183. it was very important to have had
    that kind of relationship
  184. with your father.
  185. I apologize for the sexist
    conversation here,
  186. but this is the way it really happened.
  187. He said he had been absolutely
    convinced that this was necessary,
  188. a necessary part of the growing up
    of a young physicist.
  189. Being Dick, he, of course,
    wanted to check this.
  190. He wanted to go out and do an experiment.
  191. (Laughter)
  192. Well, he did.
  193. He went out and did an experiment.
  194. He asked all his friends
    that he thought were good physicists,
  195. "Was it your mom or your pop
    that influenced you?"
  196. And to a man -
  197. they were all men,
  198. and to a man, every single
    one of them said,
  199. "My mother."
  200. (Laughter)
  201. There went that theory,
    down the trash can of history.
  202. (Laughter)
  203. But he was very excited
    that he had finally met somebody
  204. who had the same experience
    with his father
  205. as he had with his father.
  206. And for some time, he was convinced
    this was the reason we got along so well.
  207. I don't know. Maybe. Who knows?
  208. But let me tell you a little bit
    about Feynman the physicist.
  209. Feynman's style --
    no, "style" is not the right word.
  210. "Style" makes you think
    of the bow tie he might have worn,
  211. or the suit he was wearing.
  212. It's something much deeper than that,
  213. but I can't think of another word for it.
  214. Feynman's scientific style
    was always to look for the simplest,
  215. most elementary solution
    to a problem that was possible.
  216. If it wasn't possible,
    you had to use something fancier.
  217. No doubt, part of this
    was his great joy and pleasure
  218. in showing people that he could
    think more simply than they could.
  219. But he also deeply believed,
    he truly believed,
  220. that if you couldn't explain
    something simply,
  221. you didn't understand it.
  222. In the 1950s, people
    were trying to figure out
  223. how superfluid helium worked.
  224. There was a theory.
  225. It was due to a Russian
    mathematical physicist.
  226. It was a complicated theory;
  227. I'll tell you what it was soon enough.
  228. It was a terribly complicated theory,
  229. full of very difficult
    integrals and formulas
  230. and mathematics and so forth.
  231. And it sort of worked,
    but it didn't work very well.
  232. The only way it worked
  233. is when the helium atoms
    were very, very far apart.
  234. They had to be.
  235. And unfortunately,
  236. the helium atoms in liquid helium
    are right on top of each other.
  237. Feynman decided, as a sort
    of amateur helium physicist,
  238. that he would try to figure it out.
  239. He had an idea, a very clear idea.
  240. He would try to figure out
  241. what the quantum wave function
    of this huge number of atoms looked like.
  242. He would try to visualize it,
  243. guided by a small number
    of simple principles.
  244. The small number of simple principles
    were very, very simple.
  245. The first one was that when
    helium atoms touch each other,
  246. they repel.
  247. The implication of that is that
    the wave function has to go to zero,
  248. it has to vanish when the helium
    atoms touch each other.
  249. The other fact
    is that in the ground state --
  250. the lowest energy state
    of a quantum system --
  251. the wave function is always very smooth;
  252. it has the minimum number of wiggles.
  253. So he sat down --
  254. and I imagine he had nothing more
  255. than a simple piece
    of paper and a pencil --
  256. and he tried to write down,
    and did write down,
  257. the simplest function
    that he could think of,
  258. which had the boundary conditions
  259. that the wave function
    vanish when things touch
  260. and is smooth in between.
  261. He wrote down a simple thing --
    so simple, in fact,
  262. that I suspect a really smart
    high-school student
  263. who didn't even have calculus
  264. could understand what he wrote down.
  265. The thing was, that simple thing
    that he wrote down
  266. explained everything that was known
    at the time about liquid helium,
  267. and then some.
  268. I've always wondered
    whether the professionals --
  269. the real professional helium physicists --
  270. were just a little bit
    embarrassed by this.
  271. They had their super-powerful technique,
  272. and they couldn't do as well.
  273. Incidentally, I'll tell you
    what that super-powerful technique was.
  274. It was the technique of Feynman diagrams.
  275. (Laughter)
  276. He did it again in 1968.
  277. In 1968, in my own university --
    I wasn't there at the time --
  278. they were exploring
    the structure of the proton.
  279. The proton is obviously made
    of a whole bunch of little particles;
  280. this was more or less known.
  281. And the way to analyze it was,
    of course, Feynman diagrams.
  282. That's what Feynman diagrams
    were constructed for --
  283. to understand particles.
  284. The experiments that were going on
    were very simple:
  285. you simply take the proton,
  286. and you hit it really sharply
    with an electron.
  287. This was the thing
    the Feynman diagrams were for.
  288. The only problem was that
    Feynman diagrams are complicated.
  289. They're difficult integrals.
  290. If you could do all of them,
    you would have a very precise theory,
  291. but you couldn't --
    they were just too complicated.
  292. People were trying to do them.
  293. You could do a one-loop diagram.
    Don't worry about one loop.
  294. One loop, two loops --
    maybe you could do a three-loop diagram,
  295. but beyond that, you couldn't do anything.
  296. Feynman said, "Forget all of that.
  297. Just think of the proton
  298. as an assemblage, a swarm,
    of little particles."
  299. He called them "partons."
  300. He said, "Just think of it as a swarm
    of partons moving real fast."
  301. Because they're moving real fast,
  302. relativity says the internal
    motions go very slow.
  303. The electron hits it suddenly --
  304. it's like taking a very sudden
    snapshot of the proton.
  305. What do you see?
  306. You see a frozen bunch of partons.
  307. They don't move,
  308. and because they don't move
    during the course of the experiment,
  309. you don't have to worry
    about how they're moving.
  310. You don't have to worry
    about the forces between them.
  311. You just get to think of it
    as a population of frozen partons."
  312. This was the key to analyzing
    these experiments.
  313. Extremely effective.
  314. Somebody said the word
    "revolution" is a bad word.
  315. I suppose it is,
    so I won't say "revolution,"
  316. but it certainly evolved very, very deeply
    our understanding of the proton,
  317. and of particles beyond that.
  318. Well, I had some more
    that I was going to tell you
  319. about my connection with Feynman,
  320. what he was like,
  321. but I see I have exactly half a minute.
  322. So I think I'll just finish up by saying:
  323. I actually don't think
    Feynman would have liked this event.
  324. I think he would have said,
    "I don't need this."
  325. But ...
  326. (Laughter)
  327. How should we honor Feynman?
  328. How should we really honor Feynman?
  329. I think the answer
    is we should honor Feynman
  330. by getting as much baloney
    out of our own sandwiches
  331. as we can.
  332. Thank you.
  333. (Applause)