Application of the Non-Perturbative Renormalization Group to the Nambu-Jona-Lasinio model at Finite Temperature and Density

摘要

The chiral phase structure of the Nambu- Jona-Lasinio/Gross-Neveu model at finite temperature T and finite chemical potential μ is explored using the (Wilsonian) non-perturbative renormalization group (NPRG). In the large N_C limit, the solutions of NPRG with various cutoff schemes are given. We show that results consistent with those for the Schwinger-Dyson equation can be obtained in the framework of the NPRG method. Next, to improve the approximation, we incorporate the mesonic fluctuations. The N_C dependence of the chiral phase diagram is obtained.