Nathaniel
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 Mar 15 reviewed Approve Apart from friction what can be considered a non-conservative force? Mar 2 comment Why is entropy additive? @SaudiBombsYemen ah, I see. But when you sum over A and B, they are equal after all. (It that isn't clear, let me know and I'll post an answer.) Mar 1 comment Why is entropy additive? I'm pretty confused, because it looks like you start by assuming that $P(S)=P(A)P(B)$ and then show that it contradicts an assumption that $P(S)\ne P(A)P(B)$, which of course shouldn't be surprising. Have I misunderstood what you're trying to show? Feb 17 accepted What is the easiest way to stop a star? Feb 14 comment Why are magnets in form of hollow sphere not a magnetic monopole? Other possible duplicates physics.stackexchange.com/q/18115 physics.stackexchange.com/q/15655 Feb 12 awarded Notable Question Feb 9 comment How can a product of Bra and Ket be a scalar if they are matrices? +1 because that way of visualising matrix multiplication is way better than the much more awkward one I've been using all my life up to now. Feb 2 comment Reference for statistical mechanics from information theoretic view I added another Jaynes reference, which I consider one of the best - I hope you don't mind Feb 2 revised Reference for statistical mechanics from information theoretic view added 322 characters in body Jan 19 comment What are alternative ways to think about transfer matrix as used in Ising model? Oh, either's fine! I can probably work through it myself, but if you have time to put some information in the answer it might be helpful. (I just figured out that if you use the convention that stochastic matrices left-multiply probability vectors then you have to use the left Perron-Frobenius eigenvector of $T$, which is what was holding me up.) Jan 19 awarded Altruist Jan 18 awarded Investor Jan 18 comment What are alternative ways to think about transfer matrix as used in Ising model? This is an excellent answer and taught me something I needed to know. I'd really like to know more about the general case, in which the transfer matrix might not be symmetric. Jan 15 comment What would be the implications of a Penrose Universe? There are some studies of cellular automata on penrose tiling lattices, which might have something of the flavor of what you're asking for. If I get a chance I'll see if I can dig up some papers. Jan 15 comment At an instant, does a system of gravitational charges exhibit equivalent behavior to a time-reversed system of like electric charges? @endolith in GR, yes, that's true. I suppose I assumed we were in the Newtonian approximation. In the full GR case, playing the video backwards will still result in an apparent attractive force, it's just that the reversed gravitational waves will increase the energy in the system rather than decrease it over time. Jan 12 awarded Notable Question Jan 11 awarded Populist Jan 6 awarded Notable Question Jan 2 awarded Great Answer Jan 2 answered If an Ising model is in contact with two thermal reservoirs, would it still experience a phase transition if one of the reservoirs is below Tc?