arXiv subjects

Dmitri V. Fursaev

Publications and source records attributed to Dmitri V. Fursaev.

21 records · Page 2Linked to original sources

arXiv1996

Cones, Spins and Heat Kernels

The heat kernels of Laplacians for spin 1/2, 1, 3/2 and 2 fields, and the asymptotic expansion of their traces are studied on manifolds with conical singularities. The exact mode-by-mode analysis is carried out for 2-dimensional domains and then extended to arbitrary dimensions. The corrections to the first Schwinger-DeWitt coefficients in the trace expansion, due to conical singularities, are found for all the above spins. The results for spins 1/2 and 1 resemble the scalar case. However, the heat kernels of the Lichnerowicz spin 2 operator and the spin 3/2 Laplacian show a new feature. When the conical angle deficit vanishes the limiting values of these traces differ from the corresponding values computed on the smooth manifold. The reason for the discrepancy is breaking of the local translational isometries near a conical singularity. As an application, the results are used to find the ultraviolet divergences in the quantum corrections to the black hole entropy for all these spins.

hep-th↗

arXiv1995

On one-loop renormalization of black-hole entropy

One-loop divergences appearing in the entropy of a quantum black hole are proven to be completely eliminated by the standard renormalization of both the gravitational constant and other coefficients by the $R^2$-terms in the effective gravitational action. The essential point of the proof is that due to the higher order curvature terms the entropy differs from the Bekenstein-Hawking one in the Einstein gravity by the contributions depending on the internal and external geometry of the horizon surface.

hep-th↗

arXiv1994

Spectral Geometry and One-loop Divergences on Manifolds with Conical Singularities

Geometrical form of the one-loop divergences induced by conical singularities of background manifolds is studied. To this aim the heat kernel asymptotic expansion on spaces having the structure $C_α\times Σ$ near singular surface $Σ$ is analysed. Surface corrections to standard second and third heat coefficients are obtained explicitly in terms of angle $α$ of a cone $C_α$ and components of the Riemann tensor. These results are compared to ones to be already known for some particular cases. Physical aspects of the surface divergences are shortly discussed.

hep-th↗