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Electromagnetic Magic: The Relativistically Rotating Disk

D. Lynden-Bell
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Abstract

A closed form analytic solution is found for the electromagnetic field of the charged uniformly rotating conducting disk for all values of the tip speed $v$ up to $c$. For $v=c$ it becomes the Magic field of the Kerr-Newman black hole with $G$ set to zero. The field energy, field angular momentum and gyromagnetic ratio are calculated and compared with those of the electron. A new mathematical expression that sums products of 3 Legendre functions each of a different argument, is demonstrated.

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D. Lynden-Bell. 2004-10-21. Electromagnetic Magic: The Relativistically Rotating Disk. https://doi.org/10.1103/physrevd.70.105017

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