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Interaction between a stationary electric charge and a stationary magnetic dipole

W. B. Bonnor
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Abstract

Using Einstein-Maxwell theory I investigate the gravitational field generated by an electric charge and a magnetic dipole, both held in fixed positions, but spinning with prescribed angular momenta. There is a conical singularity between them representing a strut balancing the gravitational attraction of their masses. However, there is in general another singularity, which I call a torsion singularity. I interpret this as a couple needed to maintain the spins at their prescribed values. It vanishes when the parameters obey a certain formula. A conclusion of the work is that the charge and the magnet must spin relative to one another unless constrained by a couple.

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W. B. Bonnor. 2002-03-13. Interaction between a stationary electric charge and a stationary magnetic dipole. https://doi.org/10.1088/0264-9381%2F18%2F15%2F301

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