Energy Extraction from a Rotating Black Hole by Magnetic Reconnection in Ergosphere

TL;DR

This paper explores a novel energy extraction mechanism from rotating black holes via magnetic reconnection in the ergosphere, expanding understanding beyond traditional processes like Penrose and Blandford-Znajek.

Contribution

It introduces magnetic reconnection as a new process for energy extraction from black holes, detailing conditions and astrophysical implications.

Findings

Magnetic reconnection can efficiently extract energy from black holes.

Derived conditions for the process to operate in idealized plasma.

Discussed astrophysical scenarios where this mechanism is relevant.

Abstract

We investigate mechanisms of energy extraction from a rotating black hole in terms of negative energy-at-infinity. In addition to the Penrose process through particle fission, the Blandford-Znajek mechanism by magnetic tension, and the magnetohydrodynamic Penrose process, we examine energy extraction from a black hole caused by magnetic reconnection in the ergosphere. The reconnection redistributes the angular momentum efficiently to yield the negative energy-atinfinity. We derive a condition for the process to operate in a simple situation, where the plasma is incompressible and the magnetic energy is converted completely to the plasma kinetic energy locally. Astrophysical situations of magnetic reconnection around the black holes are also discussed.