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arXiv · hep-th/9406209

Remarks on Thermal Strings outside Black Holes

J. L. F. Barbon
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Abstract

We discuss the semiclassical approximation to the level density of (super) strings propagating in non-compact coset manifolds $G/H$. We show that the WKB ansatz agrees with heuristic red-shift arguments with respect to the ``exact" sigma model metric, up to some deviations from minimal coupling, parametrized by the dilaton. This approximation is used to study thermal ensembles of free strings in black holes, with the ``brick wall" regularization of `t Hooft. In two dimensions the entropy diverges logarithmically with the horizon thickness, and a local Hagedorn transition occurs in higher dimensional models. We also observe that supersymmetry improves the regularity of strings at the horizon.

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J. L. F. Barbon. 1994-06-30. Remarks on Thermal Strings outside Black Holes. https://doi.org/10.1016/0370-2693(94)91130-4

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