Black Hole fragmentation and holography

TL;DR

This paper analyzes how black hole entropy changes during fragmentation across different dimensions, revealing diverse behaviors and implications for holography and entropy bounds, especially in 2D models and field theory comparisons.

Contribution

It provides a comprehensive classification of entropy behavior under black hole fragmentation and explores the holographic implications for various gravitational solutions.

Findings

Entropy can decrease, increase, or show mixed behavior during fragmentation.

Complete characterization of 2D black hole entropy behavior based on the function J.

Holographic duals are likely field theories with a mass gap.

Abstract

We discuss the entropy change due to fragmentation for black hole solutions in various dimensions. We find three different types of behavior. The entropy may decrease, increase or have a mixed behavior, characterized by the presence of a threshold mass. For two-dimensional (2D) black holes we give a complete characterization of the entropy behavior under fragmentation, in the form of sufficient conditions imposed on the function J, which defines the 2D gravitational model. We compare the behavior of the gravitational solutions with that of free field theories in d dimensions. This excludes the possibility of finding a gravity/field theory realization of the holographic principle for a broad class of solutions, including asymptotically flat black holes. We find that the most natural candidates for holographic duals of the black hole solutions with mixed behavior are field theories with a mass gap. We also discuss the possibility of formulating entropy bounds that make reference only to the energy of a system.