Evaporation Spectrum of Black Holes from a Local Quantum Gravity Perspective

TL;DR

This paper explores the potential for a distinct line structure in black hole evaporation spectra caused by nonperturbative quantum gravity effects, specifically within the loop quantum gravity framework, which could differentiate quantum gravity models.

Contribution

It proposes that a line structure in Hawking radiation may exist far from the Planck mass due to loop quantum gravity effects, and discusses how this could distinguish different quantum gravity models.

Findings

Line structure in evaporation spectrum may persist despite quantum effects.

Low-spin transitions could cause deviations allowing model differentiation.

Effect remains despite secondary decay processes.

Abstract

We revisit the hypothesis of a possible line structure in the Hawking evaporation spectrum of black holes. Because of nonperturbative quantum gravity effects, this would take place arbitrarily far away from the Planck mass. We show, based on a speculative but consistent hypothesis, that this naive prediction might in fact hold in the specific context of loop quantum gravity. A small departure from the ideal case is expected for some low-spin transitions and could allow us to distinguish several quantum gravity models. We also show that the effect is not washed out by the dynamics of the process, by existence of a mass spectrum up to a given width, or by the secondary component induced by the decay of neutral pions emitted during the time-integrated evaporation.