Penrose At Work

TL;DR

This paper explores a novel astrophysical mechanism where orbiting material around a supermassive black hole can be ejected with negative energy during a black hole merger, potentially enabling energy extraction from the black hole.

Contribution

It proposes a new scenario for Penrose process activation during black hole mergers involving orbiting material at ISCO.

Findings

Orbiting material can be ejected with negative energy during black hole plunge.

The mechanism offers a plausible astrophysical energy extraction process.

Potential implications for black hole energetics and astrophysical observations.

Abstract

If a supermassive black hole has some material orbiting around it at close to its innermost stable circular orbit (ISCO), then, when it plunges into a second supermassive black hole, the orbiting material has a velocity dispersion of order of speed of light about the orbital velocity of its host black hole. It becomes plausible that some of the orbiting material will be "catapulted" to the negative-energy ergosphere orbits of the second black hole at the plunge. This may provide an astrophysically plausible way to extract energy from the black hole, originally suggested by Penrose.