Abstract Employing a new theorem on time ordered products of operators, an infinite hierarchy of equations for the finite temperature Green functions of a many particle system is obtained. The analysis provides a basis for the extension to finite temperatures of recent results from ground state perturbation theory. The connection between the present analysis and the corresponding ground state formalism is briefly discussed.

physica status solidi (b)Oct 1, 19810 citations

Il Nuovo cimento della Società italiana di fisica. B/Il Nuovo cimento B

A new perturbative approach to the study of quantum systems at finite temperature

A. Riccardi

Published May 1, 1990• 0 citations

Publisher

DOI: 10.1007/bf02722884

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