Light Probes in a Strongly Coupled Anisotropic Plasma

TL;DR

This paper uses gauge/gravity duality to analyze how anisotropy in a strongly coupled plasma affects light probe jet quenching, revealing orientation-dependent suppression and enhancement of stopping distances.

Contribution

It provides the first detailed calculation of light probe stopping distances in an anisotropic strongly coupled plasma using holography.

Findings

Stopping distances are suppressed along the longitudinal direction in anisotropic plasma.

Near transverse directions, stopping distances can slightly exceed isotropic values at fixed entropy.

Anisotropy generally increases jet quenching in the plasma.

Abstract

We employ the gauge/gravity duality to study the jet quenching of light probes traversing a static yet anisotropic strongly coupled $\mathcal{N}=4$ super Yang-Mills plasma. We compute the stopping distance of an image jet induced by a massless source field, which is characterized by a massless particle falling along the null geodesic in the WKB approximation, in an anisotropic dual geometry introduced by Mateos and Trancancelli. At mid and large anisotropic regimes, the stopping distances of a probe traveling in the anisotropic plasma along various orientations are suppressed compared to those in an isotropic plasma especially along the longitudinal direction at equal temperature. However, when fixing the entropy density, the anisotropic values of stopping distances near the transverse directions slightly surpass the isotropic values. In general, the jet quenching of light probes is increased by the anisotropic effect in a strongly coupled and equilibrium plasma.