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Entropy generation in 2+1-dimensional Gravity

Francois Englert·Benni Reznik
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Abstract

The tunneling approach, for entropy generation in quantum gravity, is shown to be valid when applied to 3-D general relativity. The entropy of de Sitter and Reissner-Nordström external event horizons and of the 3-D black hole obtained by Bañados et. al. is rederived from tunneling of the metric to these spacetimes. The analysis for spacetimes with an external horizon is carried out in a complete analogy with the 4-D case. However, we find significant differences for the black hole. In particular the initial configuration that tunnels to a 3-D black hole may not to yield an infinitely degenerate object, as in 4-D Schwarzschild black hole. We discuss the possible relation to the evaporation of the 3-D black hole.

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Francois Englert, Benni Reznik. 1994-01-12. Entropy generation in 2+1-dimensional Gravity. https://doi.org/10.1103/physrevd.50.2692

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