Dimensional analysis involving partial derivatives

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SUMMARY

Dimensional analysis in statistical physics reveals that the relationship $$\frac{1}{\beta} = kT$$ holds true, where ##\beta## is defined as ##\frac{\partial \ln \Omega}{\partial E}## and k represents the Boltzmann constant. The analysis confirms that the dimensions of the derivative ##\partial{ln (\Omega)}/\partial{E}## are indeed 1/energy, leading to the conclusion that the units of ##1/\beta## correspond to energy, matching the dimensions of ##kT##. This clarification addresses common confusions regarding the dimensionality of logarithmic functions.

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  • Understanding of statistical physics concepts, particularly the Boltzmann constant.
  • Familiarity with dimensional analysis and its applications in physics.
  • Knowledge of partial derivatives and their significance in mathematical expressions.
  • Basic comprehension of logarithmic functions and their dimensionality.
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  • Learn about the applications of partial derivatives in physical systems.
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Wledig
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It is mentioned in Reif's book, statistical physics, that trough dimensional analysis it can be shown that: $$\frac{1}{\beta} = kT $$ where ##\beta## equals ##\frac{\partial \ln \Omega}{\partial E}## and k is the Boltzmann constant. I don't quite see how to reach this result, can anyone give me a hand here?
 
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The dimensions of dA/dB are A/B, for any two quantities A and B. You can see that from the definition of derivative.

The log is dimensionless (arguments of logs, exponentials, trig functions should always be dimensionless). So the units of ##\partial{ln (\Omega)}/\partial{E}## are 1/energy.

Therefore the units of ##1/\beta## are energy, and those are the dimensions of ##kT##
 
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Thanks, I wasn't sure about what to do with the ln. Got intimidated, I guess.
 

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