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arXiv · hep-th/9512177

Supersymmetric Black Holes in $N=8$ Supergravity

Ramzi Khuri·Tomas Ortin
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Abstract

We study the embedding of extreme (multi-) dilaton black hole solutions for the values of the parameter $a=\sqrt{3},1,1/\sqrt{3},0$ in $N=4$ and $N=8$ four-dimensional supergravity. For each black hole solution we find different embeddings in $N=4$ supergravity which have different numbers of unbroken supersymmetries. When embedded in $N=8$ supergravity, all different embeddings of the same solution have the same number of unbroken supersymmetries. Thus, there is a relation between the value of the parameter $a$ and the number of unbroken supersymmetries in $N=8$ supergravity, but not in $N=4$, and the different embeddings must be related by dualities of the $N=8$ theory which are not dualities of the $N=4$ theory. The only exception in this scheme is a {\it dyonic} embedding of the $a=0$ black-hole solution which seems to break all supersymmetries both in the $N=4$ and in the $N=8$ theories.

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Ramzi Khuri, Tomas Ortin. 1996-02-02. Supersymmetric Black Holes in $N=8$ Supergravity. https://doi.org/10.1016/0550-3213(96)00112-5

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