Anisotropic drag force in finite-density QGP from charged rotating 5D black holes

TL;DR

This paper investigates the anisotropic drag force on a heavy quark in a finite-density, rotating holographic plasma modeled by 5D black holes, providing exact and perturbative results with physical implications.

Contribution

It derives exact and perturbative expressions for the anisotropic drag force on a heavy quark in a rotating, charged holographic plasma using 5D black hole duals, including regularity conditions.

Findings

Exact drag force in neutral Kerr--AdS limit for arbitrary rotation.

Finite transverse drag force in charged, slow-rotation regime.

Unique co-rotating equilibrium quark identified in equal-spin sector.

Abstract

We study the drag force acting on a heavy quark in a holographic plasma with rotational anisotropy and finite density. The bulk dual is the CCLP black hole of five-dimensional minimal gauged supergravity, characterised by two independent rotation parameters and electric charge. In the neutral Kerr--AdS limit, we use the principal Killing string to obtain an exact drag force for arbitrary rotation parameters. The resulting force is purely tangential but generically anisotropic, reducing to the viscous form only in the equal-spin sector. We then analyse stationary strings in the charged CCLP background perturbatively in the slow-rotation regime. A regularity analysis of the Lorentzian worldsheet fixes the angular integration constants that would otherwise remain ambiguous, yielding a finite renormalised transverse drag force with a smooth Kerr--AdS limit. We also show that, in the equal-spin sector, worldsheet regularity selects a unique co-rotating equilibrium quark and compute its renormalised free-energy shift.