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arXiv · 1903.01203

Gravitational electromotive force in magnetic reconnection around Schwarzschild black holes

Felipe A. Asenjo·Luca Comisso
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Abstract

We analytically explore the effects of the gravitational electromotive force on magnetic reconnection around Schwarzschild black holes through a generalized general-relativistic magnetohydrodynamic model that retains two-fluid effects. It is shown that the gravitational electromotive force can couple to collisionless two-fluid effects and drive magnetic reconnection. This is allowed by the departure from quasi-neutrality in curved spacetime, which is explicitly manifested as the emergence of an effective resistivity in Ohm's law. The departure from quasi-neutrality is owed to different gravitational pulls experienced by separate parts of the current layer. This produces an enhancement of the reconnecion rate due to purely gravitational effects.

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Felipe A. Asenjo, Luca Comisso. 2019-03-04. Gravitational electromotive force in magnetic reconnection around Schwarzschild black holes. https://doi.org/10.1103/physrevd.99.063017

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