Near extremal Kerr entropy from AdS 2 quantum gravity

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. © 2009 SISSA.