Journal of Mathematical Physics

Grassmann algebra and fermions in the lattice: A simple example

S. M. de Souza, M. T. Thomaz

Published Dec 1, 1991• 4 citations

Abstract

Using the exact results for integrals of exponentials of polynomials of Grassmann variables and the Feynman construction of path integrals, an approximate method is presented to calculate the thermodynamic quantities of a fermionic system in equilibrium with a reservoir at temperature T and chemical potential μ. To exemplify, the quantum anharmonic fermionic oscillator is considered in a lattice with N points, where N=2, 3, and 4.

DOI: 10.1063/1.529459

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