Electromagnetic quasinormal modes of rotating black strings and the AdS/CFT correspondence

TL;DR

This paper studies the electromagnetic quasinormal modes of rotating black strings in AdS space and explores their dual CFT plasma behavior, revealing effects like Doppler shifts and thermalization time dilation.

Contribution

It provides a detailed analysis of electromagnetic perturbations of rotating black strings and their holographic duals, including both analytical and numerical results on quasinormal modes.

Findings

Rotation causes Doppler shifts in QNM frequencies.

Rotation affects thermalization times in the dual CFT.

Hydrodynamic regime of QNM dispersion relations is analytically characterized.

Abstract

We investigate the quasinormal spectrum of electromagnetic perturbations of rotating black strings. Among the solutions of Einstein equations in the presence of a negative cosmological constant there are asymptotically anti-de Sitter (AdS) black holes whose horizons have the topology of a cylinder. The stationary version of these AdS black holes represents rotating black strings. The conformal field theory (CFT) dual of a black string lives in a Minkowski space with a compact dimension. On the basis of the AdS/CFT duality, we interpret a CFT plasma moving with respect to the preferred rest frame introduced by the topology as the holographic dual to a rotating black string. We explore the consequences of this correspondence by investigating the electromagnetic perturbations of a black string for different rotation parameter values. As usual the electromagnetic quasinormal modes (QNM) correspond to the poles of retarded Green's functions of $R$-symmetry currents in the boundary field theory. The hydrodynamic regime of the QNM dispersion relations are analytically studied. Finally, we investigate numerically the effect of rotation on all the family of black-string electromagnetic quasinormal modes. We interpret these results from the CFT perspective and notice the emergence of effects like Doppler shift of the frequencies and dilation of the thermalization times.