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Nonlinear sigma model approach for chiral fluctuations and symmetry breakdown in Nambu-Jona-Lasinio model

Egor Babaev
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Abstract

In this paper we discuss symmetry breakdown in NJL model at low N_c. In particular we propose a modified NJL model that displays a symmetry breakdown and also at finite temperatures under certain conditions the chiral fluctuations in this model give rise to a phase analogous to pseudogap phase of strong-coupling and low carrier density superconductors.

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Egor Babaev. 2000-06-09. Nonlinear sigma model approach for chiral fluctuations and symmetry breakdown in Nambu-Jona-Lasinio model. https://doi.org/10.1103/physrevd.62.074020

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