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arXiv · 1311.6286

Heat Kernels on the AdS(2) cone and Logarithmic Corrections to Extremal Black Hole Entropy

Rajesh Kumar Gupta·Shailesh Lal·Somyadip Thakur
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Abstract

We develop new techniques to efficiently evaluate heat kernel coefficients for the Laplacian in the short-time expansion on spheres and hyperboloids with conical singularities. We then apply these techniques to explicitly compute the logarithmic contribution to black hole entropy from an N=4 vector multiplet about a Z(N) orbifold of the near-horizon geometry of quarter--BPS black holes in N=4 supergravity. We find that this vanishes, matching perfectly with the prediction from the microstate counting. We also discuss possible generalisations of our heat kernel results to higher-spin fields over Z(N) orbifolds of higher-dimensional spheres and hyperboloids.

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Rajesh Kumar Gupta, Shailesh Lal, Somyadip Thakur. 2013-12-25. Heat Kernels on the AdS(2) cone and Logarithmic Corrections to Extremal Black Hole Entropy. https://doi.org/10.1007/jhep03(2014)043

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