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arXiv · hep-th/9405007

The Internal Geometry of an Evaporating Black Hole

Renaud Parentani·Tsvi Piran
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Abstract

We present a semi-classical model for the formation and evaporation of a four dimensional black hole. We solve the equations numerically and obtain solutions describing the entire the space-time geometry from the collapse to the end of the evaporation. The solutions satisfy the evaporation law: $\dot M \propto -M^{-2}$ which confirms dynamically that black holes do evaporate thermally. We find that the evaporation process is in fact the shrinking of a throat that connects a macroscopic interior ``universe" to the asymptotically flat exterior. It ends either by pinching off the throat leaving a closed universe and a Minkowskian exterior or by freezing up when the throat's radius approaches a Planck size. In either case the macroscopic inner universe is the region where the information lost during the evaporation process is hidden.

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Renaud Parentani, Tsvi Piran. 1994-05-05. The Internal Geometry of an Evaporating Black Hole. https://doi.org/10.1103/physrevlett.73.2805

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