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arXiv · 2411.19491

Magnetic reconnection under centrifugal and gravitational electromotive forces

Zhong-Ying Fan·Fan Zhou·Yuehang Li·Minyong Guo·Bin Chen
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Abstract

We examine the physical implications of the centrifugal and gravitational electromotive forces on magnetic reconnection in a Kerr black hole background. We find that both forces increase the reconnection rate, though the underlying mechanisms differ substantially. The gravitational force leads to a separation of charge density, breaking the quasi-neutrality of the plasma. In contrast, the centrifugal electromotive force affects the electric current by reducing the effective length of the current sheet. This reduction arises from the non-Euclidean spatial geometry observed by a locally comoving observer with respect to the rotating sheet. This phenomenon amplifies both the transport of charged carriers and the thermal-inertia effect within the current sheet, irrespective of the presence of a black hole.

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Zhong-Ying Fan, Fan Zhou, Yuehang Li, Minyong Guo, Bin Chen. 2024-11-29. Magnetic reconnection under centrifugal and gravitational electromotive forces. https://doi.org/10.1103/physrevd.111.064067

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