Decoherence of quantum superpositions by Reissner-Nordstr\"om black holes

TL;DR

This paper investigates how Reissner-Nordstr"om black holes cause decoherence in quantum superpositions of charged bodies, revealing that low-frequency photons induce decoherence except in extremal cases where the effect is suppressed.

Contribution

It extends previous work on black hole-induced decoherence to charged black holes, showing the suppression of decoherence in extremal Reissner-Nordstr"om black holes due to the Meissner effect.

Findings

Decoherence is caused by low-frequency photons crossing the horizon.

Extremal Reissner-Nordstr"om black holes suppress decoherence.

Decoherence effect is equivalent to that of ordinary matter with same size and charge.

Abstract

Recently, it was shown by Danielson-Satishchandran-Wald (DSW) that for the massive or charged body in a quantum spatial separated superposition state, the presence of a black hole can decohere the superposition inevitably towards capturing the radiation of soft photons or gravitons. In this work, we study the DSW decoherence effect for the static charged body in the Reissner-Nordstr\"om black holes. By calculating the decohering rate for this case, it is shown that the superposition is decohered by the low frequency photons that propagate through the black hole horizon. For the extremal Reissner-Nordstr\"om black hole, the decoherence of quantum superposition is completely suppressed due to the black hole Meissner effect.It is also found that the decoherence effect caused by the Reissner-Nordstr\"om black hole is equivalent to that of an ordinary matter system with the same size and charge.