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arXiv · hep-th/9602111

Macroscopic Entropy of $N=2$ Extremal Black Holes

Andrew Strominger
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Abstract

Extremal BPS-saturated black holes in $N=2$, $d=4$ supergravity can carry electric and magnetic charges $(q^Λ_{(m)},q_Λ^{(e)})$. It is shown that in smooth cases the moduli fields at the horizon take a fixed "rational" value $X^Λ(q_{(m)},q^{(e)})$ which is determined by the charges and is independent of the asymptotic values of the moduli fields. A universal formula for the Bekenstein-Hawking entropy is derived in terms of the charges and the moduli space geometry at $X^Λ(q_{(m)},q^{(e)})$. This work extends previous results of Ferrara, Kallosh and the author for the pure magnetic case.

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Andrew Strominger. 1996-03-08. Macroscopic Entropy of $N=2$ Extremal Black Holes. https://doi.org/10.1016/0370-2693(96)00711-3

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