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"I would never die for my beliefs because I might be wrong."

-- Bertrand Russell


Dec
13
revised The Concepts of Path Integral in Quantitative Finance
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Dec
13
revised The Concepts of Path Integral in Quantitative Finance
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Dec
13
answered The Concepts of Path Integral in Quantitative Finance
Dec
12
comment Which areas in physics overlap with those of social network theory for the analysis of the graphs?
I think about the field of neural networks, which in physics builds further on more complicated versions of Ising models and spin glass models. Also, in the study of the spread of diseases many results and models from physics are used. In general, I would say statistical mechanics.
Dec
12
comment How many Onsager's solutions are there?
I get the idea of what he's trying to do, but it's so long that I'm not sure how to summarize it. Maybe I'll skip the derivation of the various commutation relations and just assume them.
Dec
12
comment White Holes and Time-Reversed Oppenheimer-Snyder collapse
Of course it has everything to do with entropy. You say it yourself in your reply: "the matter distribution is something like a star that goes into the distant past" or in other words, white holes in the distant past are ruled out by postulating that the universe started in a special low entropy state that thus could not have contained white holes.
Dec
12
comment White Holes and Time-Reversed Oppenheimer-Snyder collapse
Or, if you're not that patient, here's an alternative.
Dec
12
comment White Holes and Time-Reversed Oppenheimer-Snyder collapse
In the same vein, what proves me that this entire post with your question is not just a fluctuation from an equilibrium state? If you can answer that question, you'll understand why we assume the same about white holes. I suggest reading David Albert's book where he addresses your issue.
Dec
12
comment Nonlinear optics as gauge theory
@space-cadet, that would only give a "linear material".
Dec
11
comment Irreversible expansion and time reversal symmetry
True, the wikipedia explanation for the Loschmidt paradox is quite horrible. This book by David Albert does a better job at explaining it.
Dec
11
revised Irreversible expansion and time reversal symmetry
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Dec
11
comment Irreversible expansion and time reversal symmetry
I added an extra comment in relation to your objection. Can't find a wiki page for the Zermelo paradox, except in french. I'll look for another page.
Dec
11
revised Irreversible expansion and time reversal symmetry
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Dec
11
answered How many Onsager's solutions are there?
Dec
11
comment Irreversible expansion and time reversal symmetry
It is not essential to the argument because I can start in a special state like the one constructed in 1, and then the time to reach the corner will be very small. So the real point is in explaining why such trajectories are rare.
Dec
11
comment Irreversible expansion and time reversal symmetry
Time is not important, only the relative sizes of the phase space volumes is important. I concentrated on the configurational part because that's the most easily explained and suffices to drive the point home. Second, I'm well aware that ergodicity of the system implies that the system will visit the corner again sooner or later (I implied it at the very end of the second part.) I could have added an extra computation of how long exactly it would take for a typical configuration to get in the vicinity of the corner state. But that is not the crux of the argument.
Dec
11
comment Orbital mechanics of Dragon's Egg
I've read the book's plot on the wikipage, and I just realize that a Star Trek Voyager episode, "Blink of an Eye", basically stole the plot from Dragon's Egg.
Dec
11
answered Irreversible expansion and time reversal symmetry
Dec
11
revised Electron transitions in an infinite square well
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Dec
11
revised Orbital mechanics of Dragon's Egg
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