Pressure of the O(N) Model in 1+1 Dimensions

Abstract

The O(N) model in 1+1 dimensions presents some features in common with Yang-Mills theories: asymptotic freedom, trace anomaly, non-petrurbative generation of a mass gap. An analytical approach to determine the termodynamical properties of the O(3) model is presented and compared to lattice results. Here the focus is on the pressure: it is shown how to derive the pressure in the CJT formalism at the one-loop level by making use of the auxiliary field method. Then, the pressure is compared to lattice results.

Comments: 5 pages, 1 figure. Based on the presentation of F. Giacosa at the conference ICNAAM 2012, 2nd Symposium on Analysis of Quantum Field Theory, 20-25/9/2011, Kos (Greece)