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arXiv · hep-th/0008226

Fractional Branes and the Entropy of 4D Black Holes

N. R. Constable·C. V. Johnson·R. C. Myers
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Abstract

We reconsider the four dimensional extremal black hole constructed in type IIB string theory as the bound state of D1-branes, D5-branes, momentum, and Kaluza-Klein monopoles. Specifically, we examine the case of an arbitrary number of monopoles. Consequently, the weak coupling calculation of the microscopic entropy requires a study of the D1-D5 system on an ALE space. We find that the complete expression for the Bekenstein-Hawking entropy is obtained by taking into account the massless open strings stretched between the fractional D-branes which arise in the orbifold limit of the ALE space. The black hole sector therefore arises as a mixed Higgs-Coulomb branch of an effective 1+1 dimensional gauge theory.

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N. R. Constable, C. V. Johnson, R. C. Myers. 2000-09-11. Fractional Branes and the Entropy of 4D Black Holes. https://doi.org/10.1088/1126-6708%2F2000%2F09%2F039

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