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Microscopic Entropy of Non-dilatonic Branes: a 2D approach

M. Cadoni a N. Serra
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Abstract

We investigate non-dilatonic p-branes in the near-extremal, near-horizon regime. A two-dimensional gravity model, obtained from dimensional reduction, gives an effective description of the brane. We show that the AdS_p+2/CFT_p+1 correspondence at finite temperature admits an effective description in terms of a AdS_2/CFT_1 duality endowed with a scalar field, which breaks the conformal symmetry and generates a non-vanishing central charge. The entropy of the CFT_1 is computed using Cardy formula. Fixing in a natural way a free, dimensionless, parameter introduced in the model by a renormalization procedure, we find exact agreement between the CFT_1 entropy and the Bekenstein-Hawking entropy of the brane.

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M. Cadoni a N. Serra. 2004-06-18. Microscopic Entropy of Non-dilatonic Branes: a 2D approach. https://doi.org/10.1103/physrevd.70.126003

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