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Journal of Mathematical Physics

Multivariable Grassmann integrals and the high temperature expansion of interacting fermionic models

I. C. Charret, E.V. Corrêa Silva, S. M. de Souza, M. T. Thomaz

Published Aug 1, 1995• 2 citations
Publisher

Abstract

Using the noncommuting nature of fermionic fields we obtain a nonperturbative method to calculate the high temperature limit of the grand canonical partition function of interacting fermionic models. This nonperturbative approach is applied to the Hubbard model in d=2(1+1) and we recover the known results in the limit T → ∞.
DOI
10.1063/1.530948

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