Double Relaxation via AdS/CFT

TL;DR

This paper uses the AdS/CFT correspondence to study how a strongly coupled gauge theory with fundamental matter thermalizes under a time-varying electric field, revealing the formation of apparent horizons and multiple temperature phases.

Contribution

It introduces a novel analysis of thermalization in N=2 gauge theories with fundamental matter via holography, focusing on the effects of different electric field profiles.

Findings

Two apparent horizons can form during electric field pulses.

The gauge theory exhibits two distinct temperature phases during evolution.

Different electric field functions influence horizon formation and thermalization.

Abstract

We exploit the AdS/CFT correspondence to investigate thermalization in an N=2 strongly coupled gauge theory including massless fundamental matter (quark). More precisely, we consider the response of a zero temperature state of the gauge theory under variation of an external electric field leading to a time-dependent current. The holographic dual of the above set-up is given by introducing a time-dependent electric field on the probe D7-brane embedded in an AdS_5 X S^5 background. In the dual gravity theory, due to a time-dependent electric field an apparent horizon forms on the brane which, according to AdS/CFT dictionary, is the counterpart of the thermalization process in the gauge theory. We classify different functions for time-dependent electric field and study their effect on the apparent horizon formation. In the case of pulse functions where the electric field varies from zero to zero, apart from non-equilibrium phase, we observe that two apparent horizons form on the brane. On the gauge theory side, it means that the state of the gauge theory experiences two different temperatures during the time evolution.