Scale invariant non linear sigma model at finite temperatures

[摘要] The recently proposed renormalization group improved optimized perturbation theory is employed to evaluate the pressure of the two dimensional non linear sigma model at finite temperatures. We explicitly show how this powerful resummation method can turn the lowest (one loop) perturbative contribution to the pressure, which is not RG invariant, into a non perturbative quantity exhibiting scale invariance.

[发布机构] Departamento de Física, Universidade Federal de Santa Catarina, Florianópolis, Santa Catarina; 88040-900, Brazil^1;Laboratoire Charles Coulomb (L2C), UMR 5221 CNRS, Université de Montpellier 2, Montpellier; 34095, France^2;Departamento de Física Teórica, Universidade Do Estado Do Rio de Janeiro, Rio de Janeiro, RJ; 20550-013, Brazil^3

[效力级别] 力学 [学科分类] 力学，机械学

[关键词] Finite temperatures;Nonlinear sigma model;Perturbation theory;Renormalization group;Resummation;Scale invariance;Scale invariant