The role of the ergosphere in the Blandford-Znajek process

Abstract

The Blandford-Znajek process, one of the most promising model for powering the relativistic jets from black holes, was initially introduced as a mechanism in which the magnetic fields extract energy from a rotating black hole. We study the evolution of force-free electromagnetic fields on regular spacetimes with an ergosphere, which are generated by rapidly rotating stars. Our conclusive results confirm previous works, claiming that the Blandford-Znajek mechanism is not directly related to the horizon of the black hole. We also show that the radiated energy depends exponentially on the compactness of the star.

10 pages, 11 figures. Accepted for publication in MNRAS

References in corpus (2)

• Ergoregion instability of ultra-compact astrophysical objects
• Binary black holes' effects on electromagnetic fields

Cited by in corpus (11)

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• Magnetosphere of a Kerr black hole immersed in magnetized plasma and its perturbative mode structure
• Blandford-Znajek Process in Quadratic Gravity
• Electromagnetic Energy Extraction from Kerr Black Holes: Ab-Initio Calculations
• Locating ergostar models in parameter space
• Magnetic Ergostars, Jet Formation and Gamma-Ray Bursts: Ergoregions versus Horizons
• Kerr-AdS Black Holes and Force-Free Magnetospheres
• Membrane Paradigm Approach to the Johannsen-Psaltis Black Hole
• Alfvénic superradiance for a monopole magnetosphere around a Kerr black hole