Abstract
The 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 expansion in the model by comparing results obtained numerically in dimensions at leading, next-to-leading and next-to-next-to-leading order in 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 quasiparticle properties far from equilibrium and observe rapid effective convergence already for moderate values of or the coupling.
- Received 26 September 2008
DOI:https://doi.org/10.1103/PhysRevD.78.125028
©2008 American Physical Society