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arXiv · 2507.08942

Electromagnetic Energy Extraction from Kerr Black Holes: Ab-Initio Calculations

Claudio Meringolo·Filippo Camilloni·Luciano Rezzolla
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Abstract

The possibility of extracting energy from a rotating black hole via the Blandford-Znajek mechanism represents a cornerstone of relativistic astrophysics. We present general-relativistic collisionless kinetic simulations of Kerr black-hole magnetospheres covering a wide range in the black-hole spin. Considering a classical split-monopole magnetic field, we can reproduce with these ab-initio calculations the force-free electrodynamics of rotating black holes and measure the power of the jet launched as a function of the spin. The Blandford-Znajek luminosity we find is in very good agreement with analytic calculations and compatible with general-relativistic magnetohydrodynamics simulations via a simple rescaling. These results provide strong evidence of the robustness of the Blandford-Znajek mechanism and accurate estimates of the electromagnetic luminosity to be expected in those scenarios involving rotating black holes across the mass scale.

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Claudio Meringolo, Filippo Camilloni, Luciano Rezzolla. 2025-07-11. Electromagnetic Energy Extraction from Kerr Black Holes: Ab-Initio Calculations. https://doi.org/10.3847/2041-8213%2Fae06a6

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