Friction Coefficient for Quarks in Supergravity Duals

TL;DR

This paper calculates the friction coefficient for quarks in strongly-coupled plasmas using supergravity duals, revealing that the bound on friction can be exceeded, which impacts understanding of quark dynamics in such environments.

Contribution

It provides a general method to compute quark friction coefficients in various supergravity backgrounds and challenges previous conjectures on the friction bound.

Findings

Friction coefficients can surpass previous bounds in certain supergravity backgrounds.

A general formula for the friction coefficient near the horizon is derived.

The results suggest modifications to existing conjectures on quark energy loss in strongly-coupled plasmas.

Abstract

We study quarks moving in strongly-coupled plasmas that have supergravity duals. We compute the friction coefficient of strings dual to such quarks for general static supergravity backgrounds near the horizon. Our results also show that a previous conjecture on the bound has to be modified and higher friction coefficients can be achieved.