Non-existence of New Quantum Ergosphere Effect of a Vaidya-type Black Hole

TL;DR

This paper investigates Hawking radiation in Vaidya-type black holes and finds that Dirac particles do not exhibit a new quantum ergosphere effect, with radiation characteristics similar to scalar particles.

Contribution

It demonstrates the non-existence of a new quantum ergosphere effect for Dirac particles in spherically symmetric Vaidya-type black holes.

Findings

Hawking radiation of Dirac particles occurs only for specific components.

Event horizon location and temperature vary with time.

Dirac and Klein-Gordon particles share the same thermal spectrum.

Abstract

Hawking evaporation of Dirac particles and scalar fields in a Vaidya-type black hole is investigated by the method of generalized tortoise coordinate transformation. It is shown that Hawking radiation of Dirac particles does not exist for $P_1, Q_2$ components but for $P_2, Q_1$ components in any Vaidya-type black holes. Both the location and the temperature of the event horizon change with time. The thermal radiation spectrum of Dirac particles is the same as that of Klein-Gordon particles. We demonstrates that there is no new quantum ergosphere effect in the thermal radiation of Dirac particles in any spherically symmetry black holes.