On renormalization of black hole entropy and of coupling constants

We apply the conical singularity method to calculate the tree-level entropy and its one-loop corrections for a black hole and study the statement that the divergence of the entropy can be completely removed by the renormalization of both the Newton constant and other coefficients by the curvature squared (R2) terms in the effective gravitational action. This statement is extended to the case where the theory includes not only nonminimally coupled massive scalar fields but also spinor and vector fields. This result confirms us that the renormalization statement works universally, irrespective of field species in nature.