2007/10/31 by Irene Amado, Carlos Hoyos, Karl Landsteiner +1 · 6 citations
Physics and Astronomy · #Black Holes and Theoretical Physics #Cosmology and Gravitation Theories #High-Energy Particle Collisions Research #hep-th
paper · pdf · doi:10.1103/physrevd.77.065004
published as Phys.Rev.D77:065004,2008 · 10 pages, 3 figures, revtex4, v2: improved exposition and figures
arxiv created 2008/02/28 · openalex publication_date 2008/03/05 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/28
Quasinormal modes of asymptotically AdS black holes can be interpreted as poles of retarded correlators in the dual gauge theory. To determine the response of the system to small external perturbations it is not enough to know the location of the poles: one also needs to know the residues. We compute them for R-charge currents and find that they are complex except for the hydrodynamic mode, whose residue is purely imaginary. For different quasinormal modes the residue grows with momentum \mathfrakq, whereas for the hydrodynamic mode it behaves as a damped oscillation with distinct zeroes at finite \mathfrakq. Similar to collective excitations at weak coupling the hydrodynamic mode decouples at short wavelengths. Knowledge of the residues allows as well to define the time scale \ensuremathτH from when on the system enters the hydrodynamic regime, restricting the validity of hydrodynamic simulations to times t>\ensuremathτH.