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The Day Feynman Worked Out Black-Hole Radiation on My Blackboard
- anacleto 8y agoKinda reminds of me Fermat's equation though.
- neilv 8y agoI don't think I'll ever get tired of Feynman stories.
- mrmondo 8y agoYou and I both, if you haven’t already - read ‘Surely you must be joking, Mr Feynman!”
- neilv 8y agoSome other good ones on the 'net: "Richard Feynman and the Connection Machine" http://longnow.org/essays/richard-feynman-connection-machine/ http://longnow.org/essays/richard-feynman-connection-machine... and a smaller TEDx talk on the same topic by Danny Hillis: https://www.youtube.com/watch?v=8CKW4A6jnJA https://www.youtube.com/watch?v=8CKW4A6jnJA "Los Alamos from Below" https://www.youtube.com/watch?v=_aKM-MeDMSI https://www.youtube.com/watch?v=_aKM-MeDMSI
- mrmondo 8y agoThanks for those, I don’t think I’ve seen the TED talk :)
- nihil75 8y agoDo cleaning staff actually wipe blackboards at Caltec? Makes me question the authenticity of the story.
- varelaz 8y agobut quantum representation of this information still lives somewhere in the Universe
- YayamiOmate 8y agoYea, also it seems that "had it all" might be an exaggeration... there are lots of mathematical technical details that go into those papers. I consider Feynman my idol, and he certainly could have had such idea and a shot at theory, but blackboard scribbling seems closer to napkin than a fullfledged theoretical paper. Nevertheless, cool story.
- Chris_Chambers 8y agoJews excel at embellishing stories and fanatically promoting a positive image of their fellow tribe members.
- nabla9 8y agoI think Lightman uses artistic license a lot and has rehearsed the story mulitple times in his mind. Lightman is a writer who wrote 'Einstein's Dreams'. This article is basically transcript of the interview from 2014. http://nautil.us/blog/why-hawking-radiation-was-almost-feynman-radiation http://nautil.us/blog/why-hawking-radiation-was-almost-feynm... Another weird think in the interview is Lightman saying that he don't think Feynman didn't have a big ego. Feynman loved Feynman stories and was very intellectually very competitive with his peers. His reputation and those stories were not completely spontaneous. His breakup with Gell-Mann came because he sometimes forgot that it was not he who invented all those ideas they came up together. I think one of the things that makes Feynman a bigger than life characters are his quirks and personality. There is no need to clean up his image into some king of humble guy.
- gumby 8y ago> Another weird think in the interview is Lightman saying that he don't think Feynman didn't have a big ego. I only got to know him pretty late in his life (when he was in Boston) and FWIW, compared to many folks around MIT he was not especially or showily egotistical and he had the time to talk to random students about interesting things. He was more patient than most of the MIT faculty. I can't say I was some sort of pal or anything so perhaps I got the benefit of a more edited persona?
- comboy 8y agoThis just says he came to the conclusion that there should be spontaneous emission and estimated it. Coming up with how it actually happens (particle-antiparticle pair) is another story, so it seems a bit unfair to Hawking to say that Feynman got it first.
- coldtea 8y agoWhat other thing could be the emission? Besides, isn't particle-antiparticle pair obvious, if one knows about their spontaneous appearance?
- nocturnial 8y agoThe particle-antiparticle explanation is just an analogy and doesn't really cover what actually happens. I thought this video from PBS Space Time explains it really well while keeping it accessible for non-physicists: https://www.youtube.com/watch?v=qPKj0YnKANw https://www.youtube.com/watch?v=qPKj0YnKANw
- stcredzero 8y agoAnd that video is good background info for the one on the Unruh Effect, which I found truly mind-blowing! https://www.youtube.com/watch?v=7cj6oiFDEXc https://www.youtube.com/watch?v=7cj6oiFDEXc Any time we accelerate, we produce a distant effective event horizon behind us! Also, "The Unruh" would make for a good name for aliens in Star Control!
- terryf 8y agoIt's more complex than that. If it was that simple, it would emit particles and antiparticles randomly which would not lead to losing mass.
- doubleunplussed 8y agoWhat? Particles and antiparticles both have positive mass, as far as we know. Emitting either or both would be a loss of mass.
- vanderZwan 8y ago> But when I got back to my office in the morning, the cleaning lady had wiped the blackboard clean. Didn't something that happen to the notes of a very famous mathematician as well? That they were burned by the person cleaning up his belongings after he died?
- reallymental 8y agoPerhaps you're thinking of Fermat[0], who famously remarked "I have discovered a truly remarkable proof of this theorem which this margin is too small to contain.", and promptly proceeded to take the solution with him to the other side. I doubt anyone burned his manuscripts however, but I seem to recall an article where they mentioned that everyone searched for the solution (or for his approach) in every one of his notebooks, but couldn't find it. [0] https://en.wikiquote.org/wiki/Pierre_de_Fermat https://en.wikiquote.org/wiki/Pierre_de_Fermat
- tragomaskhalos 8y agoIsn't the accepted version of this that Fermat thought he had an elegant solution, but had actually made some simple logical error in his reasoning? And Andrew Wiles' solution is certainly not simple. However it is very seductive to imagine that Fermat was correct, and it's just that no-one since has had the insight to rediscover it.
- anacleto 8y agoVery seductive but highly unrealistic. Wiles' proof required math techniques undiscovered at the time Fermat made this famous statement.
- whatshisface 8y agoJust because our proof is complicated does not mean Fermat's proof couldn't have been simple, as no exhaustive search of all possible short proofs has ever been carried out. Vanishingly unlikely yes, but not proven false, and after all it is exceedingly romantic. ;)
- foobarbecue 8y ago`Feynman said that what Bill and Saul were describing sounded like simulated emission...` Proof we live in a simulation! (presumably this is a typo)
- zeristor 8y agoThis made me wonder if Rick Sanchez was based on Richard Feynman?
- bjornsing 8y agoSounds credible, up to the point about the cleaning lady... If he realized their importance, why would he not be able to work out the equations again, possibly with Feynman’s help?
- huhtenberg 8y agoPrecisely! Violating the sanctity of one's blackboards is one of the worst possible offenses in the academic world. Cleaning staff sure knows better than even glancing in their approximate direction.
- JoeAltmaier 8y agoWas that true in the 1050's? 1960's? Back then, the upper-class folk who inhabited offices would not think of emptying a wastepaper basket, clearing a desk, cleaning a floor. They may have had different expectations about who's job it was to erase the chalkboard as well.
- mannykannot 8y agoI would guess the cleaners would clean off the board only if the author had made it very clear, some time beforehand, that this is what he wanted and expected.
- paulpauper 8y agothere are multiple derivations. my guess is he used the simpler of the two that does not require the field equation: https://en.wikipedia.org/wiki/Hawking_radiation https://en.wikipedia.org/wiki/Hawking_radiation
- mannykannot 8y agoFeynman's argument is made from a phenomenon predicted for rotating black holes, that is analogous to stimulated emission. I believe Hawking radiation is predicted for all black holes, whether rotating or not, so I am wondering if there is a phenomenon analogous to stimulated emission from non-rotating black holes? (I am making an analogy of analogies here: if the original phenomenon is like stimulated emission from rotating black holes, and Hawking radiation is the corresponding spontaneous emission, then is Hawking radiation from stationary black holes also like spontaneous emission, and if so, what is the corresponding stimulated emission?)
- StopClickBait 8y agoThis story may or may not be true, either way it encapsulates what a scientist should be: distracted by reality and allowing other smart people to play their roles. Feynman had his own things to work on, and clearly there were more people needed for humans to advance.
- Mugwort 8y agoThis is not at all unusual. Poincare discovered special relativity before Einstein, Hilbert found the correct equations for General relativity one week before Einstein, Hamilton almost discovered quantum mechanics decades before everyone else. Newton found solutions to major mathematical problems and never published them. Gauss discovered hyperbolic geometry before Bolyai and Lobachevski and never bothered publishing his results. I can go on and on in the fields of physics and mathematics which I know best. Certainly, the same thing is true in chemistry, biology, etc. I wouldn't doubt someone got there before even Feynman did. Still in every case, the recognized discoverer not only made their discoveries independently but also managed to convince their communities of their merit, something which is FAR harder to do. This smells like classic Feynman. He did more things than people realize even coming up with his own ideas about the Riemann hypothesis even though he wasn't a mathematician at all. In a certain sense Feynman didn't discover a single physical law. (arguable) . This little anecdote if true would be Feynman's "single" discovery of an actual new physic law (which happens to not have experimental verification). Feynman was brilliant. If you have a physics PhD you can still benefit enormously by reading Feynman's lectures on physics. His work on statistical mechanics is essential reading too especially if you already know everything.
- stcredzero 8y agoThis smells like classic Feynman. He did more things than people realize... He used to be ribbing Danny Hillis all the time, saying that he came up with just about all of Computer Science during the Manhattan Project. "Just what is it that you do again?"
- fosco 8y agoMathematics is discovered not invented. The way I understand it.
- CalChris 8y agoThe article doesn't explain why light would bounce off a rotating black hole and that doesn't make intuitive sense to me. I think of light as bouncing off of surfaces and I think of a black hole as being an event horizon and stuff inside. Does anyone have an explanation for this?
- lostmsu 8y agoAFAIK, Hawking got the idea of black hole radiation from Zeldovich. See https://en.m.wikipedia.org/wiki/Hawking_radiation#Discovery https://en.m.wikipedia.org/wiki/Hawking_radiation#Discovery