Out of equilibrium O (N) linear-sigma system - Construction of perturbation theory with gap- and Boltzmann-equations

Abstract

We establish from first principles a perturbative framework that allows us to compute reaction rates for processes taking place in nonequilibrium $O(N)$ linear-sigma systems in broken phase. The system of our concern is quasiuniform system near equilibrium or nonequilibrium quasistationary system. We employ the closed-time-path formalism and use the so-called gradient approximation. No further approximation is introduced. In the course of construction of the framework, we obtain the gap equation that determines the effective masses of $\pi$ and of $\sigma$, and the generalized Boltzmann equation that describes the evolution of the number-density functions of $\pi$ and of $\sigma$.

18 pages

References in corpus (4)

• Out of Equilibrium Quantum Field Theory --- Perturbation Theory and Generalized Boltzmann Equation
• Effects of friction on the chiral symmetry restoration in high energy heavy-ion collisions
• Reaction-rate formula in out of equilibrium quantum field theory
• Pion dispersion relation at finite temperature in the linear sigma model from chiral Ward identities

Cited by in corpus (3)

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