Finding beta for the boltzman distribution.

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The discussion focuses on deriving the Boltzmann distribution using Lagrange multipliers, leading to the expression P(i) = (1/Z)e^(-βE(i)), where Z is the partition function. The key question is how to establish that β = 1/kT, particularly for a monatomic ideal gas. The mean energy is derived as U = -∂lnZ/∂β and compared to U = (3/2)NkT to validate the relationship. There is a reference to Leonard Susskind's lectures for further clarification on the derivation. The conversation also raises the point that the Boltzmann distribution should apply to various systems sharing total energy E and particle number N.
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Hello! I'm trying to do a satisfactory derivation of the Boltzmann distribution. By using lagrange multipliers I've come as far as to prove that

P(i) = \frac{1}{Z} e^{-\beta E(i)}
where
Z = \sum_i e^{-\beta E(i)},

but how does one actually establish that
\beta = 1/kT?
 
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Take a monatomic ideal gas and derive the mean energy,

U=-\frac{\partial \ln Z}{\partial \beta}

and compare with the definition of the temperature,

U=\frac{3}{2} N k T.
 
I think that Leonard Susskind does this derivation in one of his lectures on statistical mechanics that is available on youtube.

http://www.youtube.com/watch?v=H1Zbp6__uNw"
 
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Take a monatomic ideal gas and derive the mean energy
Ah, yes that is certainly a way to go. But how could that result possibly be general? Doesn't the distribution apply to any combination of systems who shares a total energy E and a number of particles N?
 
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