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arXiv · 1303.4913

On the quantum-field description of many-particle Fermi systems with spontaneously broken symmetry

Yu. M. Poluektov
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Abstract

A quantum-field approach for describing many-particle Fermi systems at finite temperatures and with spontaneously broken symmetry has been proposed. A generalized model of self-consistent field (SCF), which allows one to describe the states eligible for this system with various symmetries, is used as the initial approximation. A perturbation theory has been developed, and a diagram technique for temperature Green's functions (GFs) has been constructed. The Dyson's equation for the self-energy and vertex parts has been deduced.

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Yu. M. Poluektov. 2013-03-20. On the quantum-field description of many-particle Fermi systems with spontaneously broken symmetry. https://arxiv.org/abs/1303.4913

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