V. Moretti, GEOMETRIC ENTROPY AND CURVATURE COUPLING IN CONICAL SPACES - ZETA-FUNCTION APPROACH, Classical and quantum gravity, 14(5), 1997, pp. 123-127
The local xi-function approach is implemented to regularize the natura
l path integral definition of the geometric entropy in the large mass
black hole Euclidean manifold. The case of a massless field coupled wi
th the (off-shell) singular curvature is considered. It is proved that
the geometric entropy is independent of the curvature coupling parame
ter, xi, avoiding the negative values obtained in other approaches.