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Universal Bound on Dynamical Relaxation Times and Black-Hole Quasinormal Ringing

Shahar Hod
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Abstract

From information theory and thermodynamic considerations a universal bound on the relaxation time $τ$ of a perturbed system is inferred, $τ\geq \hbar/πT$, where $T$ is the system's temperature. We prove that black holes comply with the bound; in fact they actually {\it saturate} it. Thus, when judged by their relaxation properties, black holes are the most extreme objects in nature, having the maximum relaxation rate which is allowed by quantum theory.

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Shahar Hod. 2006-11-01. Universal Bound on Dynamical Relaxation Times and Black-Hole Quasinormal Ringing. https://doi.org/10.1103/physrevd.75.064013

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