Schwarzschild-de Sitter spacetime: the role of Temperature in the emission of Hawking radiation

TL;DR

This paper investigates how different temperature definitions influence Hawking radiation emission from Schwarzschild-de Sitter black holes, revealing that only certain temperatures support significant radiation and that scalar coupling affects emission rates.

Contribution

It analyzes six temperature models in SdS spacetime and assesses their impact on Hawking radiation spectra and emissivities, highlighting the role of non-minimal coupling.

Findings

Few temperature models support significant radiation emission.

Non-minimal coupling influences energy emission rates.

Temperature choice affects Hawking radiation profiles.

Abstract

We consider a Schwarzschild-de Sitter (SdS) black hole, and focus on the emission of massless scalar fields either minimally or non-minimally coupled to gravity. We use six different temperatures, two black-hole and four effective ones for the SdS spacetime, as the question of the proper temperature for such a background is still debated in the literature. We study their profiles under the variation of the cosmological constant, and derive the corresponding Hawking radiation spectra. We demonstrate that only few of these temperatures may support significant emission of radiation. We finally compute the total emissivities for each temperature, and show that the non-minimal coupling constant of the scalar field to gravity also affects the relative magnitudes of the energy emission rates.