Near Extremal Kerr Entropy from AdS_2 Quantum Gravity

TL;DR

This paper uses AdS_2/CFT_1 correspondence to analyze near extremal Kerr black holes, deriving their entropy from asymptotic symmetries and confirming consistency with the Bekenstein-Hawking law.

Contribution

It identifies a Virasoro algebra with a specific central charge in the near horizon geometry and computes the entropy using Cardy's formula, providing a quantum gravity perspective.

Findings

Virasoro algebra with c_R=12J identified

Entropy matches Bekenstein-Hawking law

Consistent with AdS_2/CFT_1 correspondence

Abstract

We analyze the asymptotic symmetries of near extremal Kerr black holes in four dimensions using the AdS_2/CFT_1 correspondence. We find a Virasoro algebra with central charge c_R=12J that is independent from the Virasoro algebra (with the same central charge) that acts on the degenerate ground state. The energy of the excitations is computed as well, and we can use Cardy's formula to determine the near extremal entropy. Our result is consistent with the Bekenstein-Hawking area law for near extremal Kerr black holes.