Scalar radiation emitted from a source rotating around a black hole

TL;DR

This paper studies scalar radiation from a rotating source near a Schwarzschild black hole, finding that relativistic orbits emit less power than in flat spacetime and most energy escapes to infinity.

Contribution

It introduces a quantum field theory framework to analyze scalar radiation in curved spacetime, specifically around black holes, highlighting differences from flat spacetime emissions.

Findings

Relativistic circular orbits emit 20-30% less power than in Minkowski space.

Most of the emitted energy escapes to infinity.

The formalism can be adapted for similar radiation process investigations.

Abstract

We analyze the scalar radiation emitted from a source rotating around a Schwarzschild black hole using the framework of quantum field theory at the tree level. We show that for relativistic circular orbits the emitted power is about 20% to 30% smaller than what would be obtained in Minkowski spacetime. We also show that most of the emitted energy escapes to infinity. Our formalism can readily be adapted to investigate similar processes.