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Grassmann Algebra and Fermions at Finite Temperature

I. C. Charret·E. V. Corrêa Silva·S. M. de Souza·O. Rojas Santos·M. T. Thomaz
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Abstract

For any d-dimensional self-interacting fermionic model, all coefficients in the high-temperature expansion of its grand canonical partition function can be put in terms of multivariable Grassmann integrals. A new approach to calculate such coefficients, based on direct exploitation of the grassmannian nature of fermionic operators, is presented. We apply the method to the soluble Hatsugai-Kohmoto model, reobtaining well-known results.

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I. C. Charret, E. V. Corrêa Silva, S. M. de Souza, O. Rojas Santos, M. T. Thomaz. 1998-09-21. Grassmann Algebra and Fermions at Finite Temperature. https://doi.org/10.1063/1.533008

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