2003/03/31 by Gert Aarts, Jose M. Martinez Resco, Jose M. Martínez Resco · 1 citation
Mathematics · Physics and Astronomy · #Action (physics) #Black Holes and Theoretical Physics #Effective action #Fermion #Field (mathematics) #High-Energy Particle Collisions Research #Logarithm #Mathematical analysis #Mathematical physics #Mathematics #Physics #Pure mathematics #Quantum #Quantum Chromodynamics and Particle Interactions #Quantum field theory #Quantum gravity #Quantum mechanics #Quartic function #Scalar (mathematics) #Scalar field theory #Truncation (statistics) #hep-ph #nucl-th
paper · pdf · doi:10.1103/physrevd.68.085009
published as Phys.Rev. D68 (2003) 085009 · 5 pages, explanation in introduction expanded, summary added; to appear in PRD
arxiv created 2003/09/17 · openalex publication_date 2003/10/22 · arxiv updated 2009/11/30 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
We show that the lowest nontrivial truncation of the two-particle irreducible (2PI) effective action correctly determines transport coefficients in a weak coupling or 1/N expansion at leading (logarithmic) order in several relativistic field theories. In particular, we consider a single real scalar field with cubic and quartic interactions in the loop expansion, the O(N) model in the 2PI-1/N expansion, and QED with single and many fermion fields. Therefore, these truncations will provide a correct description, to leading (logarithmic) order, of the long time behavior of these systems, i.e. the approach to equilibrium. This supports the promising results obtained for the dynamics of quantum fields out of equilibrium using 2PI effective action techniques.