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Statistical Entropy and Superradiance in 2+1 Dimensional Acoustic Black Holes

Wontae Kim·Young-Jai Park·Edwin J. Son·Myung Seok Yoon
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Abstract

We study ``draining bathtub'' as an acoustic analogue of a three-dimensional rotating black hole. Rotating fluid near the sonic horizon necessarily gives rise to the superradiant modes, which are partially responsible for the thermodynamic quantities in this rotating vortex-like hole. Using the recently suggested thin-layer method overcoming some difficulties from the well-known brick-wall method, we explicitly calculate the free energy of the system by treating the superradiance carefully and obtain the desirable entropy formula.

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Wontae Kim, Young-Jai Park, Edwin J. Son, Myung Seok Yoon. 2006-03-28. Statistical Entropy and Superradiance in 2+1 Dimensional Acoustic Black Holes. https://arxiv.org/abs/gr-qc/0504127

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