On thermalization of a boost-invariant non Abelian plasma

TL;DR

This paper uses holographic methods to study how a non-Abelian plasma thermalizes and reaches hydrodynamic behavior after being driven out-of-equilibrium by boundary deformations, finding it occurs within about 1 fm/c.

Contribution

It investigates the effects of different boundary deformation profiles on the thermalization process of a non-Abelian plasma using holography, extending previous models.

Findings

Hydrodynamic regime is reached after approximately 1 fm/c.

Boundary deformations influence the thermalization time.

Effective temperature at quench end is set to 500 MeV.

Abstract

Using a holographic method, we further investigate the relaxation towards the hydrodynamic regime of a boost-invariant non-Abelian plasma taken out-of-equilibrium. In the dual description, the system is driven out-of-equilibrium by boundary sourcing, a deformation of the boundary metric, as proposed by Chesler and Yaffe. The effects of several deformation profiles on the bulk geometry are investigated by the analysis of the corresponding solutions of the Einstein equations. The time of restoration of the hydrodynamic regime is investigated: setting the effective temperature of the system at the end of the boundary quenching to $T_{eff}(\tau^*)=500$ MeV, the hydrodynamic regime is reached after a lapse of time of ${\cal O}$(1 fm/c).