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Evaluating the partition function for systems with long range interactions

Tong Zhou
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Abstract

We express the partition function for an equilibrium system of interacting particles in the canonical ensemble as a functional integration over the particles' density field. We outline a method to evaluate the partition function by expanding around a saddle point. The saddle point is shown to be the solution of the equivalent mean-field theory. Leading corrections to the mean-field theory takes the form of a Gaussian integral.

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Tong Zhou. 1999-05-17. Evaluating the partition function for systems with long range interactions. https://doi.org/10.1016/s0375-9601(00)00148-1

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