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arXiv · hep-th/9111044

Modified Black Holes in Two Dimensional Gravity

N. Mohammedi
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Abstract

The $SL(2,R)/U(1)$ gauged WZWN model is modified by a topological term and the accompanying change in the geometry of the two dimensional target space is determined. The possibility of this additional term arises from a symmetry in the general formalism of gauging an isometry subgroup of a non-linear sigma model with an antisymmetric tensor. It is shown, in particular, that the space-time exhibits some general singularities for which the recently found black hole is just a special case. From a conformal field theory point of view and for special values of the unitary representations of $SL(2,R)$, this topological term can be interpreted as a small perturbation by a (1,1) conformal operator of the gauged WZWN action.

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N. Mohammedi. 1991-11-22. Modified Black Holes in Two Dimensional Gravity. https://doi.org/10.1016/0370-2693(92)90271-5

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