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arXiv · 0807.2571

Phase structure of the massive chiral Gross-Neveu model from Hartree-Fock

Christian Boehmer·Ulf Fritsch·Sebastian Kraus·Michael Thies
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Abstract

The phase diagram of the massive chiral Gross-Neveu model (the massive Nambu-Jona-Lasinio model in 1+1 dimensions) is constructed. In the large N limit, the Hartree-Fock approach can be used. We find numerically a chiral crystal phase separated from a massive Fermi gas phase by a 1st order transition. Using perturbation theory, we also construct the critical sheet where the homogeneous phase becomes unstable in a 2nd order transition. A tricritical curve is located. The phase diagram is mapped out as a function of fermion mass, chemical potential and temperature and compared with the one of the discrete chiral Gross-Neveu model. As a by-product, we illustrate the crystal structure of matter at zero temperature for various densities and fermion masses.

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Christian Boehmer, Ulf Fritsch, Sebastian Kraus, Michael Thies. 2008-07-16. Phase structure of the massive chiral Gross-Neveu model from Hartree-Fock. https://doi.org/10.1103/physrevd.78.065043

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