Abstract
We study the thermodynamics of massive Gross-Neveu models with explicitly broken discrete or continuous chiral symmetries for finite temperature and fermion densities. The large N limit is discussed, paying attention to the no-go theorems for symmetry breaking in two dimensions which apply to the massless cases. The main purpose of the study is to serve as an analytical orientation for the more complex problem of the chiral transition in four-dimensional QCD with quarks. For any nonvanishing fermion mass, we find, at finite densities, lines of first-order phase transitions. For small mass values, traces of would-be second-order transitions and a tricritical point are recognizable. We study the thermodynamics of these models, and in the model with broken continuous chiral symmetry we examine the properties of the pionlike state.
- Received 13 June 1994
DOI:https://doi.org/10.1103/PhysRevD.51.3042
©1995 American Physical Society