Particle density in zero temperature symmetry restoring phase transitions in four-fermion interaction models

Zhou Bang-Rong

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Particle density in zero temperature symmetry restoring phase transitions in four-fermion interaction models

Zhou Bang-Rong

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Abstract

By means of critical behaviors of the dynamical fermion mass in four-fermion interaction models, we have shown by explicit calculations that when T=0 the particle density will have a discontinuous jumping across the critical chemical potential $μ_c$ in 2D and 3D Gross-Neveu (GN) model and these physically explain the first order feature of corresponding symmetry restoring phase transitions. For second order phase transitions in 3D GN model when $T\to 0$ and in 4D Nambu-Jona-Lasinio (NJL) model when T=0, it has been proven that the particle density itself will be continuous across $μ_c$ but its derivative over the chemical potential $μ$ will have a discontinuous jumping. The results give a physical explanation of implications of the tricritical point $(T,μ)=(0,μ_c)$ in 3D GN model. The discussions also show effectiveness of the critical analysis approach of phase transitions.

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Zhou Bang-Rong. 2003-08-21. Particle density in zero temperature symmetry restoring phase transitions in four-fermion interaction models. https://arxiv.org/abs/hep-th/0308139

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