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Absorption of photons and fermions by black holes in four dimensions

Steven S. Gubser
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Abstract

The absorption of photons and fermions into four-dimensional black holes is described by equations which in certain cases can be analyzed using dyadic index techniques. The resulting absorption cross-sections for near-extremal black holes have a form at low energies suggestive of the effective string model. A coupling to the effective string is proposed for spin-0 and spin-1/2 fields of pure N=4 supergravity which respects the unbroken supersymmetry of extreme black holes and correctly predicts dilaton, axion, and fermion cross-sections up to an overall normalization.

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Steven S. Gubser. 1997-09-19. Absorption of photons and fermions by black holes in four dimensions. https://doi.org/10.1103/physrevd.56.7854

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