Finding beta for the boltzman distribution.

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    Beta Distribution
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Discussion Overview

The discussion centers around the derivation of the Boltzmann distribution and the relationship between the parameter beta and temperature in statistical mechanics. Participants explore theoretical aspects and implications related to ideal gases and energy distributions.

Discussion Character

  • Exploratory
  • Technical explanation
  • Conceptual clarification

Main Points Raised

  • One participant presents a derivation of the Boltzmann distribution using Lagrange multipliers and seeks to establish the relationship between beta and temperature.
  • Another participant suggests deriving the mean energy of a monatomic ideal gas and comparing it with the definition of temperature as a method to relate beta to temperature.
  • A third participant references a lecture by Leonard Susskind that may cover the derivation in question, indicating a potential resource for further understanding.
  • A later reply questions the generality of the mean energy derivation, suggesting that the Boltzmann distribution should apply to various systems with shared total energy and particle numbers.

Areas of Agreement / Disagreement

Participants do not appear to reach a consensus on the generality of the mean energy derivation or the relationship between beta and temperature, indicating multiple competing views and unresolved questions.

Contextual Notes

There are limitations regarding assumptions about the systems being discussed, the dependence on specific definitions of temperature, and the scope of the derivations presented.

center o bass
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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

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

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

[tex]U=-\frac{\partial \ln Z}{\partial \beta}[/tex]

and compare with the definition of the temperature,

[tex]U=\frac{3}{2} N k T.[/tex]
 
Last edited by a moderator:
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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