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arXiv · 1607.06222

Hints of quantum gravity from the horizon fluid

Bethan Cropp·Swastik Bhattacharya·S. Shankaranarayanan
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Abstract

For many years researchers have tried to glean hints about quantum gravity from black hole thermodynamics. However, black hole thermodynamics suffers from the problem of Universality --- at leading order, several approaches with different microscopic degrees of freedom lead to Bekenstein-Hawking entropy. We attempt to bypass this issue by using a minimal statistical mechanical model for the horizon fluid based on Damour-Navier-Stokes (DNS) equation. For stationary asymptotically flat black hole spacetimes in General Relativity, we show explicitly that at equilibrium the entropy of the horizon fluid is the Bekenstein-Hawking entropy. Further we show that, for the bulk viscosity of the fluctuations of the horizon fluid to be identical to Damour, a confinement scale exists for these fluctuations, implying quantization of the horizon area. The implications and possible mechanisms from the fluid point of view are discussed.

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Bethan Cropp, Swastik Bhattacharya, S. Shankaranarayanan. 2016-07-21. Hints of quantum gravity from the horizon fluid. https://doi.org/10.1103/physrevd.95.024006

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