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arXiv · 0912.2664

Competing mechanisms of chiral symmetry breaking in a generalized Gross-Neveu model

Christian Boehmer·Michael Thies
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Abstract

Chiral symmetry of the 2-dimensional chiral Gross-Neveu model is broken explicitly by a bare mass term as well as a splitting of scalar and pseudo-scalar coupling constants. The vacuum and light hadrons - mesons and baryons which become massless in the chiral limit - are explored analytically in leading order of the derivative expansion by means of a double sine-Gordon equation. Depending on the parameters, this model features new phenomena as compared to previously investigated 4-fermion models: spontaneous breaking of parity, a non-trivial chiral vacuum angle, twisted kink-like baryons whose baryon number reflects the vacuum angle, crystals with alternating baryons, and appearance of a false vacuum.

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Christian Boehmer, Michael Thies. 2010-03-10. Competing mechanisms of chiral symmetry breaking in a generalized Gross-Neveu model. https://doi.org/10.1103/physrevd.81.105027

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