Counting Dyons in N = 4 String Theory
نویسندگان
چکیده
We present a microscopic index formula for the degeneracy of dyons in four-dimensional N = 4 string theory. This counting formula is manifestly symmetric under the duality group, and its asymptotic growth reproduces the macroscopic Bekenstein-Hawking en-tropy. We give a derivation of this result in terms of the type II ve-brane compactiied on K3, by assuming that its uctuations are described by a closed string theory on its world-volume. We nd that the degeneracies are given in terms of the denominator of a generalized super Kac-Moody algebra. We also discuss the correspondence of this result with the counting of D-brane states.
منابع مشابه
ar X iv : h ep - t h / 96 07 02 6 v 1 3 J ul 1 99 6 July 1996 cern - th / 96 - 170 Counting Dyons in N = 4 String Theory
We present a microscopic index formula for the degeneracy of dyons in four-dimensional N = 4 string theory. This counting formula is manifestly symmetric under the duality group, and its asymptotic growth reproduces the macroscopic Bekenstein-Hawking entropy. We give a derivation of this result in terms of the type II five-brane compactified on K3, by assuming that its fluctuations are describe...
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