Partition function & Boltzman, Maxwell distri

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Discussion Overview

The discussion centers on the relationship between the partition function and the Maxwell-Boltzmann (MB) distribution, exploring their differences and similarities. Participants examine the implications of these concepts in statistical mechanics, particularly regarding microstates, energy distributions, and the applicability of the partition function to various physical quantities.

Discussion Character

  • Exploratory
  • Technical explanation
  • Conceptual clarification
  • Debate/contested

Main Points Raised

  • Some participants note that both the partition function and the MB distribution involve exponentials of the negative total energy of microstates, although the term "microstate" is not explicitly used in the context of the MB distribution.
  • It is suggested that the MB distribution focuses on the velocity and position of particles, while the partition function encompasses broader macro variables such as energy, pressure, and temperature, without directly calculating particle speeds or positions.
  • One participant questions whether the MB distribution can be considered a more specialized entity compared to the partition function and asks if the partition function can be used to calculate particle positions and velocities.
  • Another participant states that the MB distributions can be derived from the energy probability distribution, indicating that they represent the same concept expressed in different variables.
  • A later reply challenges the idea of deriving the partition function from the MB distribution, suggesting that in cases involving potential energy, the expression for energy would need to be modified to include both kinetic and potential energy terms.

Areas of Agreement / Disagreement

Participants express differing views on the relationship between the partition function and the MB distribution, with some suggesting they are closely related while others argue that the partition function cannot be derived from the MB distribution. The discussion remains unresolved regarding the extent to which the partition function can be used to calculate specific particle properties.

Contextual Notes

Participants acknowledge that the discussion may depend on specific definitions and assumptions regarding microstates, energy distributions, and the contexts in which these concepts are applied. There are indications of unresolved mathematical steps in relating the partition function to the MB distribution.

pivoxa15
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What is the relation between the partition function and the Boltzmann, Maxwell distribution?

Differences and similarities?

Both have exponentials to the power of the negative total energy of the microstate. Although the word microstate doesn't occur in the Boltzmann, Maxwell case.

Is the BM distribution about velocity and position of particles only whereas the partition function is about any distribution involving macro variables? So it cannot calculate the speeds and position of particles in the system but can tell you about energy, pressure, temperture etc.
 
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The normalization constant of the energy probability distribution of a system is one over the partition function.

In the MB distribution, the system is a single particle in the heat bath of all the rest. The microstates are that particle at different energies (kinetic + potential if any).
 
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So the MB is a more specialised or more restricted entity? Could you use the partition function to calculate position and velocity of particles?
 
Interesting but you can't derive the partition function from the MB?

If you had non gas with potential energy than you would replace E=p^2/(2m) with K+U?

Then you would get the more general MB disbribution.
 

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