Sectors of solutions in three-dimensional gravity and black holes

We examine the connection between three-dimensional gravity with negative cosmological constant and two-dimensional CFT via the Chern–Simons formulation. A set of generalized spectral flow transformations are shown to yield new sectors of solutions. One implication is that the microscopic calculation of the entropy of the Bañados–Teitelboim–Zanelli (BTZ) black hole is corrected by a multiplicative factor with the result that it saturates the Bekenstein–Hawking expression.