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arXiv · hep-th/9712150

Black holes and Elementary String States in N=2 Supersymmetric String Theories

Ashoke Sen
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Abstract

We compare the logarithm of the degeneracy of BPS saturated elementary string states and the string modified Bekenstein-Hawking entropy of the corresponding black holes in N=2 supersymmetric heterotic string compactification to four dimensions. As in the case of N=4 supersymmetric theory, the two results match up to an overall undetermined numerical factor. We also show that this undetermined numerical constant is identical in the N=2 and N=4 supersymmetric theories, therby showing that the agreement between the Bekenstein-Hawking entropy and the microscopic entropy for N=2 theories does not require any new identity, other than the one already required for the N=4 theory. A similar result holds for type II string compactification as well.

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Ashoke Sen. 1998-04-06. Black holes and Elementary String States in N=2 Supersymmetric String Theories. https://doi.org/10.1088/1126-6708%2F1998%2F02%2F011

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