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CFT, Holography, and Causal Entropy Bound

R. Brustein·S. Foffa·G. Veneziano
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Abstract

The causal entropy bound (CEB) is confronted with recent explicit entropy calculations in weakly and strongly coupled conformal field theories (CFTs) in arbitrary dimension $D$. For CFT's with a large number of fields, $N$, the CEB is found to be valid for temperatures not exceeding a value of order $M_P/N^{1\over D-2}$, in agreement with large $N$ bounds in generic cut-off theories of gravity, and with the generalized second law. It is also shown that for a large class of models including high-temperature weakly coupled CFT's and strongly coupled CFT's with AdS duals, the CEB, despite the fact that it relates extensive quantities, is equivalent to (a generalization of) a purely holographic entropy bound proposed by E. Verlinde.

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R. Brustein, S. Foffa, G. Veneziano. 2001-01-15. CFT, Holography, and Causal Entropy Bound. https://doi.org/10.1016/s0370-2693(01)00172-1

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