Sparsity of the Hawking flux

TL;DR

The paper discusses the extreme sparsity of Hawking radiation emitted by black holes, emphasizing that quanta are emitted infrequently, suggesting black hole evaporation resembles a sequence of individual decay events.

Contribution

It provides a detailed analysis of the sparsity of Hawking flux, highlighting its implications for understanding black hole evaporation as a series of discrete emissions.

Findings

Hawking flux is extremely sparse and thin.

Time between emitted quanta is much longer than their energy timescale.

Black hole evaporation resembles a sequence of 2-body decays.

Abstract

It is (or should be) well-known that the Hawking flux that reaches spatial infinity is extremely sparse, and extremely thin, with the Hawking quanta, one-by-one, slowly dribbling out of the black hole. The typical time between quanta reaching infinity is much larger than the timescale set by the energy of the quanta. Among other things, this means that the Hawking evaporation of a black hole should be viewed as a sequential cascade of 2-body decays.