Quasinormal modes and holography

TL;DR

This paper explores quasinormal modes in asymptotically AdS spacetime and their relation to poles in Green's functions within the holographic dual of strongly coupled finite temperature field theories, providing explicit calculations.

Contribution

It explicitly computes poles of retarded correlators in N=4 SYM theory, linking quasinormal modes to holographic Green's functions in a finite temperature setting.

Findings

Identifies quasinormal frequencies with Green's function poles.

Calculates retarded correlators for R-symmetry currents.

Analyzes gravitational and electromagnetic perturbations in AdS.

Abstract

Quasinormal frequencies of electromagnetic and gravitational perturbations in asymptotically AdS spacetime can be identified with poles of the corresponding real-time Green's functions in a holographically dual finite temperature field theory. The quasinormal modes are defined for gauge-invariant quantities which obey incoming-wave boundary condition at the horizon and Dirichlet condition at the boundary. As an application, we explicitly find poles of retarded correlation functions of R-symmetry currents and the energy-momentum tensor in strongly coupled finite temperature N=4 supersymmetric SU(Nc) Yang-Mills theory in the limit of large Nc.