Low-energy sector quantization of a massless scalar field outside a Reissner-Nordstrom black hole and static sources

TL;DR

This paper investigates the behavior of a massless scalar field near a charged black hole, analyzing how static sources respond to Hawking radiation and comparing it with accelerated sources in flat spacetime, revealing differences from uncharged black holes.

Contribution

It introduces a low-energy quantization method for scalar fields outside Reissner-Nordstrom black holes and compares source responses in different vacua, highlighting unique effects of black hole charge.

Findings

Static sources respond differently to Hawking radiation in charged versus uncharged black holes.

The response of static sources differs from that of uniformly accelerated sources in Minkowski vacuum.

Reissner-Nordstrom black holes exhibit distinct quantum effects compared to Schwarzschild black holes.

Abstract

We quantize the low-energy sector of a massless scalar field in the Reissner-Nordstrom spacetime. This allows the analysis of processes involving soft scalar particles occurring outside charged black holes. In particular, we compute the response of a static scalar source interacting with Hawking radiation using the Unruh (and the Hartle-Hawking) vacuum. This response is compared with the one obtained when the source is uniformly accelerated in the usual vacuum of the Minkowski spacetime with the same proper acceleration. We show that both responses are in general different in opposition to the result obtained when the Reissner-Nordstrom black hole is replaced by a Schwarzschild one. The conceptual relevance of this result is commented.