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The Thermodynamic Pressure of a Dilute Fermi Gas

Robert Seiringer
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Abstract

We consider a gas of fermions with non-zero spin at temperature $T$ and chemical potential $μ$. We show that if the range of the interparticle interaction is small compared to the mean particle distance, the thermodynamic pressure differs to leading order from the corresponding expression for non-interacting particles by a term proportional to the scattering length of the interparticle interaction. This is true for any repulsive interaction, including hard cores. The result is uniform in the temperature as long as $T$ is of the same order as the Fermi temperature, or smaller.

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Robert Seiringer. 2004-12-23. The Thermodynamic Pressure of a Dilute Fermi Gas. https://doi.org/10.1007/s00220-005-1433-3

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