Energy-momentum tensor near an evaporating black hole

Abstract

%'e calculate the vacuum expectation value, T"", of the energy-momentum tensor of a massless scalar field in a general two-dimensional spacetime and evaluate it in a two-dimensional model of gravitational collapse. In two dimensions, quantum radiation production is incompatible with a conserved and traceless T"".We therefore resolve an ambiguity in our expression for T~", regularized by a geodesic point-separation procedure, by demanding conservation but allowing a trace. In the collapse model, the results support that picture of black-hole evaporation in which pairs of particles are created outside the horizon (and not entirely in the collapsing matter), one of which carries negative energy into the future horizon of the black hole, while the other contributes to the thermal flux at infinity.

Entropy evolution of moving mirrors and the information loss problem

“…By using this relation, one can further estimate the out-going energy flux according to the Davies-Fulling-Unruh formula [27] as a functional of the entanglement entropy [24,26]:…”

Hawking radiation by effective two-dimensional theories

“…It will be of fundamental relevance for the subsequent discussion. Let us consider, to limit the mathematical complexity, the simple case where the black hole is formed by the collapse of a shock-wave at v = v 0 [25] (for the timelike case see for instance [26]). In the "in" region v < v 0 the space-time is flat…”

A study of Universal thermodynamics in Lanczos–Lovelock gravity

“…This connection was established by the pioneering work of Bekenstein, Hawking, Davies, Unruh and others showing that horizons in general possess thermodynamic properties like entropy [18,19] and temperature [20,21,22,23]. The gravitational field equations in Einstein and in more general gravity theories [24,25,26] as well as in all the Lanczos-Lovelock models can be derived from a thermodynamical extremum principle [13] and the action functional itself can be given a thermodynamic interpretation.…”