Black Hole Entropy and Gravity Cutoff

TL;DR

This paper explores black hole entropy as entanglement entropy, proposing that the gravitational cutoff depends on the number of species, resolving the species puzzle through explicit theoretical examples.

Contribution

It introduces a natural resolution to the species puzzle by linking the gravitational cutoff to the number of species, supported by explicit theoretical examples.

Findings

The gravitational cutoff scales as M_{Planck}/√N in the presence of N species.

Equality of black hole entropy and entanglement entropy is demonstrated in specific models.

The resolution aligns with fundamental theory predictions.

Abstract

We study the black hole entropy as entanglement entropy and propose a resolution to the species puzzle. This resolution comes out naturally due to the fact that in the presence of $N$ species the universal gravitational cutoff is $\Lambda=M_{\rm Planck}/\sqrt{N}$, as opposed to $M_{\rm Planck}$. We demonstrate consistency of our solution by showing the equality of the two entropies in explicit examples in which the relation between $M_{\rm Planck}$ and $\Lambda$ is known from the fundamental theory.