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

-- Bertrand Russell


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
edited title
Dec
11
revised Orbital mechanics of Dragon's Egg
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Dec
11
awarded  Organizer
Dec
11
revised What does an atom radiate: a wave packet or a single photon?
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Dec
11
comment White Holes and Time-Reversed Oppenheimer-Snyder collapse
Yes, and the entropy of an egg is the same regardless of wether it comes before the chicken or after the chicken. But which evolution is more likely, the one where a chicken lays an egg out of which comes a new chicken or the one where a chicken gets into an egg and hops inside another chicken?
Dec
11
awarded  Enthusiast
Dec
11
awarded  Enlightened
Dec
11
awarded  Nice Answer
Dec
10
comment Nonlinear optics as gauge theory
Ansatz is fine, one could substitute the word postulate for it, or guess as wikipedia suggests. In his 2D Ising paper, Onsager used "eigenwert" for eigenvalue. Actually, an even better translation would be "proper value". There are a lot of German words that entered science, mainly during the period from the end of the 19th to early 20th century. "Gedankenexperiment" is another one.