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Tricritical behavior of the massive chiral Gross-Neveu model

Christian Boehmer·Michael Thies·Konrad Urlichs
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Abstract

The phase diagram of the massive chiral Gross-Neveu model (the 1+1-dimensional Nambu-Jona-Lasinio model at large N) is investigated in the vicinity of the tricritical point. Using the derivative expansion, the grand canonical potential is cast into the form of a Ginzburg-Landau effective action. Minimization of this action by variational and numerical methods reveals both 1st and 2nd order phase transitions to a chiral crystal phase, separated by a tricritical line. These findings are contrasted to the massive Gross-Neveu model with discrete chiral symmetry where only 2nd order transitions have been observed.

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Christian Boehmer, Michael Thies, Konrad Urlichs. 2007-04-30. Tricritical behavior of the massive chiral Gross-Neveu model. https://doi.org/10.1103/physrevd.75.105017

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