On the nature of entangling photons in horizon-induced decoherence

TL;DR

This paper explores how horizon-induced decoherence occurs through entangling photons in charged quantum systems, linking black hole thermodynamics and entropy bounds without flux across the horizon.

Contribution

It demonstrates that entangling photons cause decoherence by storing information inside the horizon without flux, resolving a tension with entropy bounds.

Findings

Entangling photons induce decoherence in superposed charged systems.

Decoherence occurs without flux across the horizon, aligning with entropy bounds.

The process connects horizon-induced decoherence with black hole thermodynamics.

Abstract

Recently, it was discussed how the presence of a Killing horizon induces decoherence on a quantum system in a superposition of states. Focusing on the case of an electrically-charged system with superposed positions, this would happen due to ``entangling'' photons crossing the horizon while carrying information on the superposition. Purpose of this essay is to investigate this process in connection with black hole thermodynamics and the ensuing entropy bounds. We show that an apparent tension arising with the latter is resolved provided the entangling photons, expressing a modification of the field at, as well as inside the horizon, do not give rise to a flux across it. The storage of information in this field, not retrievable from an outside observer, causes the superposition to decohere.