Expanding plasmas from anti de Sitter black holes

Abstract

We introduce a new foliation of AdS5 black holes such that the conformal boundary takes the form of a 4-dimensional FLRW spacetime with scale factor a(t). The foliation employs Eddington–Finkelstein-like coordinates and is applicable to a large class of AdS black holes, supported by matter fields or not, considerably extending previous efforts in the literature. We argue that the holographic dual picture of a CFT plasma on a FLRW background provides an interesting prototype to study the nonequilibrium dynamics of expanding plasmas and use holographic renormalization to extract the renormalized energy-momentum tensor of the dual plasma. We illustrate the procedure for three black holes of interest, namely AdS–Schwarzschild, AdS–Gauss–Bonnet, and AdS–Reissner–Nordström. For the latter, as a by-product, we show that the nonequilibrium dynamics of a CFT plasma subject to a quench in the chemical potential (i.e., a time-dependent chemical potential) resembles a cosmological evolution with the scale factor a(t) being inversely related to the quench profile μ(t).