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arXiv · 1108.6100

A Maxwell field minimally coupled to torsion

Nikodem J. Poplawski
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Abstract

We consider the Lagrangian density for a free Maxwell field, in which the electromagnetic field tensor minimally couples to the affine connection, in the Einstein-Cartan-Sciama-Kibble theory of gravity. We derive the formulae for the torsion and electromagnetic field tensors in terms of the electromagnetic potential. The divergence of the magnetic field does not vanish: the photon-torsion coupling acts like an effective magnetic monopole density. Such a coupling, which breaks U(1) gauge invariance, is significant only at extremely high energies existing in the very early Universe or inside black holes. It may, however, provide a mechanism for Dirac's quantization of electric charge.

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Nikodem J. Poplawski. 2011-08-31. A Maxwell field minimally coupled to torsion. https://arxiv.org/abs/1108.6100

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