Grassmann Algebra and Fermions at Finite Temperature
I.C. Charret, E.V. Corrêa Silva, S.M. de Souza, O. Rojas Santos, M.T. Thomaz
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.