Effective convergence of the 2PI-1/N expansion for nonequilibrium quantum fields
High Energy Physics - Phenomenology
2009-01-08 v1 High Energy Physics - Theory
Nuclear Theory
Abstract
The 1/N expansion of the two-particle irreducible effective action offers a powerful approach to study quantum field dynamics far from equilibrium. We investigate the effective convergence of the 1/N expansion in the O(N) model by comparing results obtained numerically in 1+1 dimensions at leading, next-to-leading and next-to-next-to-leading order in 1/N as well as in the weak coupling limit. A comparison in classical statistical field theory, where exact numerical results are available, is made as well. We focus on early-time dynamics and quasi-particle properties far from equilibrium and observe rapid effective convergence already for moderate values of 1/N or the coupling.
Keywords
Cite
@article{arxiv.0809.3390,
title = {Effective convergence of the 2PI-1/N expansion for nonequilibrium quantum fields},
author = {Gert Aarts and Nathan Laurie and Anders Tranberg},
journal= {arXiv preprint arXiv:0809.3390},
year = {2009}
}
Comments
4 pages, 4 eps figures