Real Time Nonequilibrium Dynamics of Quantum Plasmas. Quantum Kinetics and the Dynamical Renormalization Group

Abstract

We implement the dynamical renormalization group (DRG) using the hard thermal loop (HTL) approximation for the real-time nonequilibrium dynamics in hot plasmas. The focus is on the study of the relaxation of gauge and fermionic mean fields and on the quantum kinetics of the photon and fermion distribution functions. As a concrete physical prediction, we find that for a QGP of temperature T sim 200 MeV and lifetime 10 < t < 50 fm/c there is a new contribution to the hard (k \sim T) photon production from off-shell bremsstrahlung (q rightarrow q gamma and bar{q} rightarrow bar{q} gamma) at just O (alpha) that grows logarithmically in time and is comparable to the known on-shell Compton scattering and pair annihilation at O(alpha alpha_s).