Hawking-like radiation from evolving black holes and compact horizonless objects
arXiv:1011.5911 · doi:10.1007/JHEP02(2011)003
Abstract
Usually, Hawking radiation is derived assuming (i) that a future eternal event horizon forms, and (ii) that the subsequent exterior geometry is static. However, one may be interested in either considering quasi-black holes (objects in an ever-lasting state of approach to horizon formation, but never quite forming one), where (i) fails, or, following the evolution of a black hole during evaporation, where (ii) fails. We shall verify that as long as one has an approximately exponential relation between the affine parameters on the null generators of past and future null infinity, then subject to a suitable adiabatic condition being satisfied, a Planck-distributed flux of Hawking-like radiation will occur. This happens both for the case of an evaporating black hole, as well as for the more dramatic case of a collapsing object for which no horizon has yet formed (or even will ever form). In this article we shall cast the previous statement in a more precise and quantitative form, and subsequently provide several explicit calculations to show how the time-dependent Bogoliubov coefficients can be calculated.
V1: 34 pages. V2: 35 pages; several additional references added; this version accepted for publication in JHEP
References in corpus (10)
- A Primer for Black Hole Quantum Physics
- Black hole evaporation: A paradigm
- Fate of gravitational collapse in semiclassical gravity
- Minimal conditions for the existence of a Hawking-like flux
- Hawking-like radiation does not require a trapped region
- On the origin of the particles in black hole evaporation
- Quasi-particle creation by analogue black holes
- Sensitivity of Hawking radiation to superluminal dispersion relations
- Properties of Black Hole Radiation From Tunnelling
- The disinformation problem for black holes (conference version)