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arXiv · 1307.6122

Black-hole entropy and minimal diffusion

Michele Arzano·Gianluca Calcagni
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Abstract

The density of states reproducing the Bekenstein-Hawking entropy-area scaling can be modeled via a nonlocal field theory. We define a diffusion process based on the kinematics of this theory and find a spectral dimension whose flow exhibits surprising properties. While it asymptotes four from above in the infrared, in the ultraviolet the spectral dimension diverges at a finite (Planckian) value of the diffusion length, signaling a breakdown of the notion of diffusion on a continuum spacetime below that scale. We comment on the implications of this minimal diffusion scale for the entropy bound in a holographic and field-theoretic context.

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Michele Arzano, Gianluca Calcagni. 2013-10-11. Black-hole entropy and minimal diffusion. https://doi.org/10.1103/physrevd.88.084017

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