Evaporating black holes coupled to a thermal bath

Abstract

We study the doubly holographic model of [1] in the situation where a black hole in two-dimensional JT gravity theory is coupled to an auxiliary bath system at arbitrary finite temperature. Depending on the initial temperature of the black hole relative to the bath temperature, the black hole can lose mass by emitting Hawking radiation, stay in equilibrium with the bath or gain mass by absorbing thermal radiation from the bath. In all of these scenarios, a unitary Page curve is obtained by applying the usual prescription for holographic entanglement entropy and identifying the quantum extremal surface for the generalized entropy, using both analytical and numeric calculations. As the application of the entanglement wedge reconstruction, we further investigate the reconstruction of the black hole interior from a subsystem containing the Hawking radiation. We examine the roles of the Hawking radiation and also the purification of the thermal bath in this reconstruction.

Global symmetry, Euclidean gravity, and the black hole information problem

“…In addition to the circumstantial evidence described in the previous paragraph, we can also give a direct argument that, under a set of assumptions we state below, unitary black hole evaporation consistent with the Bekenstein-Hawking formula implies the nonexistence of global symmetries. Our argument makes use of the recent discovery that the "quantum extremal surface" (QES) formula of [12] is powerful enough to compute a unitary Page curve for an evaporating black hole in a wide variety of circumstances [13][14][15][16][17][18][19][20][21][22][23][24][25][26][27][28][29][30][31]. In this paper we will assume that the basic logic of these calculations applies in any situation where a black hole which is formed quickly evaporates in a unitary manner.…”

Islands and Page curves of Reissner-Nordström black holes

“…The Page curve of Hawking radiation was recently calculated by using the semiclassical method for two-dimensional black holes in asymptotically AdS spacetimes in Jackiw-Teitelboim (JT) gravity [6,7]. Most of the studies on the black hole information problem have been concentrated to two dimensional gravity where exact solutions incorporating the backreaction of the radiation are possible under semi-classical approximations [24][25][26][27][28][29][30][31][32][33][34][35][36]. In the two dimensional systems, islands appear at the later stage of the black evaporation, which is in the entanglement wedge of the radiation, such that the Bekenstein bound of the entanglement entropy is preserved.…”

Note on entropy dynamics in the Brownian SYK model

“…In the context of the black hole information problem [1], recent works have derived the Page curve [2] of an evaporating black hole from holographic calculations [3][4][5][6]. These calculations have been quickly generalized to various related situations [7][8][9][10][11][12][13][14][15][16][17][18][19][20][21][22][23][24][25]. In particular, using a semiclassical saddle point analysis of the gravitational path integral, it was shown that replica wormhole configurations, though exponentially suppressed, become dominant after the Page time [5,6].…”