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Timeline for Harmonic oscillator with heat bath

Current License: CC BY-SA 3.0

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Jan 5, 2016 at 15:18 vote accept Darius
Jan 5, 2016 at 6:20 answer added march timeline score: 4
Jan 5, 2016 at 5:51 comment added march The units are wrong in your last expression. The way to calculate this is to directly compute the trace in the oscillator eigenbasis. That allows you to get rid of $H$ in favor of $n$'s, and the trace turns into a geometric series and the derivative of a geometric series.
Jan 3, 2016 at 15:45 comment added Darius Now I see, that they are connected by the derivative and a minus. And I can somehow remember, that taking the derivative by $\beta$ would give the energy of the system :)
Jan 3, 2016 at 15:27 comment added udrv Ok, so calculating the partition function would indeed require use of creation & annihilation ops. It's not hard to do the trace sum though. Assuming you try this, what happens if you take the derivative on $\beta$ of $Tr\left[e^{-\beta H}\right]$?
Jan 3, 2016 at 15:08 comment added Darius The partition function is not given in the exercise, but we had that topic in thermodynamics, so I guess I could write it down. But sorry, I'm kind of stuck at that point..
Jan 3, 2016 at 14:35 comment added udrv Do you know the partition function before hand? Say you do. If you write $e^{-\frac{H}{k_BT}}$ as $e^{-\beta H}$, what relationship do you see between $Tr\left[e^{-\beta H}\right]$ and $Tr\left[H e^{-\beta H}\right]$?
Jan 3, 2016 at 14:29 history edited DanielSank CC BY-SA 3.0
fix weird math formatting
Jan 3, 2016 at 14:02 history asked Darius CC BY-SA 3.0