Geodesics with negative energy in the ergosphere of rotating black holes

TL;DR

This paper investigates the properties of negative-energy geodesics in the ergosphere of rotating black holes, demonstrating they cannot start or end within the ergosphere and must be confined within the gravitational radius.

Contribution

It provides a novel analysis showing negative-energy geodesics are confined within the ergosphere's gravitational radius, clarifying their origin and termination points.

Findings

Negative-energy geodesics cannot originate or terminate inside the ergosphere.

Their length is always finite.

They must originate and terminate inside the gravitational radius.

Abstract

It is shown that the geodesics with negative energy for rotating black holes cannot originate or terminate inside the ergosphere. Their length is always finite and this leads to conclusion that they must originate and terminate inside the gravitational radius of the ergosphere.