The Kerr/CFT correspondence

Quantum gravity in the region very near the horizon of an extreme Kerr black hole (whose angular momentum and mass are related by $J=G{M}^{2}$) is considered. It is shown that consistent boundary conditions exist, for which the asymptotic symmetry generators form one copy of the Virasoro algebra with central charge ${c}_{L}=\frac{12J}{\ensuremath{\hbar}}$. This implies that the near-horizon quantum states can be identified with those of (a chiral half of) a two-dimensional conformal field theory (CFT). Moreover, in the extreme limit, the Frolov-Thorne vacuum state reduces to a thermal density matrix with dimensionless temperature ${T}_{L}=\frac{1}{2\ensuremath{\pi}}$ and conjugate energy given by the zero mode…