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arXiv · 0806.2754

Near-horizon limit of the charged BTZ black hole and AdS_2 quantum gravity

Mariano Cadoni·Mohammad R. Setare
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Abstract

We show that the 3D charged Banados-Teitelboim-Zanelli (BTZ) black hole solution interpolates between two different 2D AdS spacetimes: a near-extremal, near-horizon AdS_2 geometry with constant dilaton and U(1) field and an asymptotic AdS_2 geometry with a linear dilaton. Thus, the charged BTZ black hole can be considered as interpolating between the two different formulations proposed until now for AdS_2 quantum gravity. In both cases the theory is the chiral half of a 2D CFT and describes, respectively, Brown-Hennaux-like boundary deformations and near-horizon excitations. The central charge c_as of the asymptotic CFT is determined by 3D Newton constant G and the AdS length l, c_as=3l/G, whereas that of the near-horizon CFT also depends on the U(1) charge Q, c_nh \propto l Q/\sqrt G.

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Mariano Cadoni, Mohammad R. Setare. 2008-06-17. Near-horizon limit of the charged BTZ black hole and AdS_2 quantum gravity. https://doi.org/10.1088/1126-6708%2F2008%2F07%2F131

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