Conformal entropy from horizon states: Solodukhin's method for
spherical, toroidal, and hyperbolic black holes in D-dimensional anti-de
Sitter spacetimes
A calculation of the entropy of static, electrically charged, black holes
with spherical, toroidal, and hyperbolic compact and oriented horizons, in D
spacetime dimensions, is performed. These black holes live in an anti-de Sitter
spacetime, i.e., a spacetime with negative cosmological constant. To find the
entropy, the approach developed by Solodukhin is followed. The method consists
in a redefinition of the variables in the metric, by considering the radial
coordinate as a scalar field. Then one performs a 2+(D-2) dimensional
reduction, where the (D-2) dimensions are in the angular coordinates, obtaining
a 2-dimensional effective scalar field theory. This theory is a conformal
theory in an infinitesimally small vicinity of the horizon. The corresponding
conformal symmetry will then have conserved charges, associated with its
infinitesimal conformal generators, which will generate a classical Poisson
algebra of the Virasoro type. Shifting the charges and replacing Poisson
brackets by commutators, one recovers the usual form of the Virasoro algebra,
obtaining thus the level zero conserved charge eigenvalue L_0, and a nonzero
central charge c. The entropy is then obtained via the Cardy formula.Comment: 21 page