1212.4176 (Mehdi Saravani et al.)

Empty Black Holes, Firewalls, and the Origin of Bekenstein-Hawking Entropy    [PDF]

Mehdi Saravani, Niayesh Afshordi, Robert B. Mann

We propose a novel solution for the endpoint of gravitational collapse, in which spacetime ends (and is orbifolded) at a microscopic distance from black hole event horizons. This model is motivated by the emergence of singular event horizons in the gravitational aether theory, a semi-classical solution to the cosmological constant problem(s), and thus suggests a catastrophic breakdown of general relativity close to black hole event horizons. A similar picture emerges in fuzzball models of black holes in string theory, as well as the recent firewall proposal to resolve the information paradox. We then demonstrate that positing a surface fluid with vanishing energy density (but non-vanishing pressure) at the new boundary of spacetime, which is required by Israel junction conditions, yields a thermodynamic entropy that is identical to the Bekenstein-Hawking area law for charged rotating black holes. To our knowledge, this is the first derivation of black hole entropy which only employs local thermodynamics. Finally, a model for the microscopic degrees of freedom of the surface fluid (which constitute the micro-states of the black hole) is suggested, which has a finite, but Lorentz-violating, quantum field theory.

View original: http://arxiv.org/abs/1212.4176