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Journal of Physics A Mathematical and General

Renormalised perturbation theory of ordered systems

W. E. Hagston, Colin John Lambert

Published Aug 1, 1981• 1 citation
Publisher

Abstract

Introduces a new self-consistent summation procedure for the analysis of Feynman-Dyson perturbation series and demonstrate how a self-consistent expression for the self-energies of an interacting system may be obtained. The authors obtain the simplest self-consistent solution to the problem of an interacting many fermion system exhibiting long-range order, characterised by the existence of anomalous propagators, in which correlation effects not described by the Hartree-Fock-Gorkov approximation are important.

DOI
10.1088/0305-4470/14/8/016

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