Yea, 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.
I 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-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.
> 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?
Assuming Feynman's identity and self worth were tied around his intellect, accomplishments and reputation. I don't think his identity was challenged in day-to-day encounters with his students and colleges. Only people like Gell-Mann might be able to push his buttons. If I remember correctly the stories, the two were always trying to one-up each other even in trivial matters. That kind of mutual challenging was probably beneficial.
Ego is weird word because it can mean opposite things in common use. "Weak ego" - person is easily upset when their identity is challenged. "Strong ego" or "big ego" - used as positive thing, opposite of weak ego. "big ego" - used negatively as synonym for egoistic, selfish or self centered. "egotistic" - excessive and objectionable reference to oneself in conversation or writing; conceit; boastfulness, selfishness
This 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.
The 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
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!
Ok, to be fair I'm not a physicist but it would seem to me that if you get a stream of mixed particles and anti-particles, they would annihilate, thus not producing a mass difference.
That "annihilation" doesn't lead to non-existence, it does lead to transformation. You get energy rather than matter... Which would still lead to mass loss so long as that energy didn't end up back in the black hole. And very much not a physicist myself...
Right, but the charges of particle-antiparticle pairs do cancel out, so there is no net energy produced.
Quick thought experiment: two particle-antiparticle pairs get created:
p1-ap1, p2-ap2
In regular space, after a very short amount of time p1 annihilates with ap1 and p2 with ap2. Net result is zero additional matter and energy, otherwise we'd just be creating random matter and/or energy everywhere.
If the same happens at the event horizon of a black hole and let's assume purely by chance, p1 and ap2 fall in and p2 and ap1 do not. After a short while, p1 and ap2 annihilate inside and p2 and ap1 outside. The result should be effectively the same as in the previous case, thus zero net energy and/or matter on either side. Thus, also no radiation and mass loss.
It'd be nice if an actual physicist chimed in at this point and told me where I went wrong :)
For the charge to matter, you're saying that charges infer positive or negative mass. But that's original responder's point.... both the particle and anti-particle both have positive mass regardless of their charge, which is a different attribute.
Consider how it is you are conserving energy/mass in your thought experiment. Seems like you might be creating a back door whereby that mass/energy is not conserved in order to preserve charge conservation.
The epistemological reality of those events are not as simple as you assume. For the most part, that annihilation event is a short-hand analogy for a term in an equation. Another way to think of it is that this 'happening everywhere' style of particle-anti-particle annihilation relies on the inherent uncertainty of energy over short time scales, and thus it 'borrows' energy that doesn't exist in order to precede, but under any measurable timescale the energy must be conserved, and so these events are likewise unobservable. So it's not a simple matter to assume they happen, or that they are the same phenomenon as annihilation in general.
Massless particles exist, and I believe this goes to the concept that particle and anti-particle pairs exist everywhere, and annihilate each other very very fast.
If you put an object into empty space, sunlight will hit it and get hot. Don't have an object in empty space? Something has to be there.
It might be part of that region in space, or it might be some property of the object emitting energy.
It help me to think of this as a model. It works, whether we have an intuitive understanding of it or not. Light comes on, wall gets bright. Whether it's ripples in a connected medium, or collisions between little projectiles, we know it's always going to be the same.
What I'm thinking about is if black holes are not really black and have some light to them, can suns sort of be black holes too? Can we thread particles around it's outer orbit, to gain control of the gravity internal to the star, and also pull out more from what's around it?
This happens in patents where the law distinguishes between obviousness (section 103 rejection) and novelty (section 102 rejection). You can invent something which is in fact novel but still obvious.
> I am always skeptical of retrospective claims of obviousness (partly from the number of times I have seen it made in math textbooks.)
I agree with you about your claim, but not about your justification. I believe that "historically obvious" things ("that's the first thing I would have thought of in that situation; how did it take them so long?") are usually subject to considerable ex post facto bias.
On the other hand, when a mathematics textbook says that something is obvious, it means, or should mean: we've specifically set up the presentation to this point so that there's a unique best way to assemble the material so far, and that unique best way will accomplish the next step. This isn't always true when it's claimed, but it is possible in textbooks in a way that it isn't (or that has only a small probability) in history, since textbooks are consciously organised and history isn't.
Also, this says it was a year before Hawking published his paper. Presumably he'd been working on it for quite a while before he published so I'm not sure it's fair to say Feynman was "first".
This isn't about priority, and that is clearly something that Feynman did not care about. It is about Feynman's astonishing ability to make fruitful connections.
> 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.
It is analogous to evolution of how stimulated and spontaneous emission were explained microscopically in the first place:
For the case of general photon behavior, Einstein showed that the statistics of photons phenomenologically demanded that there be a stimulated process; and then (several decades later) QED provided a microscopic description of how stimulated and spontaneous processes work.
For the case of black holes, it seemed that Feynman noticed that a stimulated-like process was occurring, which (again, probably because of statistics) phenomenologically demands that there be an associated spontaneous process; and then (merely one year later) Hawking provided a microscopic description of how the spontaneous process works.
To be honest, I've never heard anyone talk about stimulated emission from black holes in the context of Hawking radiation, but perhaps it is well-known to those in the field.
> 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?
Perhaps 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.
Isn'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.
Just 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. ;)
Sounds 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?
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.
Was 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.
I 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.
Feynman'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?)
This 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.
This 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.
This 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?"
The 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?
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[ 2.6 ms ] story [ 138 ms ] thread"Richard Feynman and the 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
"Los Alamos from Below" https://www.youtube.com/watch?v=_aKM-MeDMSI
Makes me question the authenticity of the story.
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.
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.
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?
Ego is weird word because it can mean opposite things in common use. "Weak ego" - person is easily upset when their identity is challenged. "Strong ego" or "big ego" - used as positive thing, opposite of weak ego. "big ego" - used negatively as synonym for egoistic, selfish or self centered. "egotistic" - excessive and objectionable reference to oneself in conversation or writing; conceit; boastfulness, selfishness
Besides, isn't particle-antiparticle pair obvious, if one knows about their spontaneous appearance?
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!
Quick thought experiment: two particle-antiparticle pairs get created:
p1-ap1, p2-ap2
In regular space, after a very short amount of time p1 annihilates with ap1 and p2 with ap2. Net result is zero additional matter and energy, otherwise we'd just be creating random matter and/or energy everywhere.
If the same happens at the event horizon of a black hole and let's assume purely by chance, p1 and ap2 fall in and p2 and ap1 do not. After a short while, p1 and ap2 annihilate inside and p2 and ap1 outside. The result should be effectively the same as in the previous case, thus zero net energy and/or matter on either side. Thus, also no radiation and mass loss.
It'd be nice if an actual physicist chimed in at this point and told me where I went wrong :)
For the charge to matter, you're saying that charges infer positive or negative mass. But that's original responder's point.... both the particle and anti-particle both have positive mass regardless of their charge, which is a different attribute.
Consider how it is you are conserving energy/mass in your thought experiment. Seems like you might be creating a back door whereby that mass/energy is not conserved in order to preserve charge conservation.
The actual physicist is Richard Feynman, and here is a Feynman diagram of a particle-antiparticle annihilation.
* https://commons.wikimedia.org/wiki/File:Mutual_Annihilation_...
If you put an object into empty space, sunlight will hit it and get hot. Don't have an object in empty space? Something has to be there.
It might be part of that region in space, or it might be some property of the object emitting energy.
It help me to think of this as a model. It works, whether we have an intuitive understanding of it or not. Light comes on, wall gets bright. Whether it's ripples in a connected medium, or collisions between little projectiles, we know it's always going to be the same.
What I'm thinking about is if black holes are not really black and have some light to them, can suns sort of be black holes too? Can we thread particles around it's outer orbit, to gain control of the gravity internal to the star, and also pull out more from what's around it?
I agree with you about your claim, but not about your justification. I believe that "historically obvious" things ("that's the first thing I would have thought of in that situation; how did it take them so long?") are usually subject to considerable ex post facto bias.
On the other hand, when a mathematics textbook says that something is obvious, it means, or should mean: we've specifically set up the presentation to this point so that there's a unique best way to assemble the material so far, and that unique best way will accomplish the next step. This isn't always true when it's claimed, but it is possible in textbooks in a way that it isn't (or that has only a small probability) in history, since textbooks are consciously organised and history isn't.
It is analogous to evolution of how stimulated and spontaneous emission were explained microscopically in the first place:
For the case of general photon behavior, Einstein showed that the statistics of photons phenomenologically demanded that there be a stimulated process; and then (several decades later) QED provided a microscopic description of how stimulated and spontaneous processes work.
For the case of black holes, it seemed that Feynman noticed that a stimulated-like process was occurring, which (again, probably because of statistics) phenomenologically demands that there be an associated spontaneous process; and then (merely one year later) Hawking provided a microscopic description of how the spontaneous process works.
To be honest, I've never heard anyone talk about stimulated emission from black holes in the context of Hawking radiation, but perhaps it is well-known to those in the field.
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?
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
Agree on that part. (:
Probably one of those apocryphal stories that died when the internet came along (I remember first hearing of this two decades ago).
Proof we live in a simulation! (presumably this is a typo)
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.
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.
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?"
The way I understand it.