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arXiv · 1706.07665

Lorentz covariant and gauge invariant description of orbital and spin angular momentum and the non-symmetric energy momentum tensor

Richard T. Hammond
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Abstract

Starting from covariant expressions, a gauge independent separation of orbital and spin angular momentum for electrodynamics is presented. This results from the non-symmetric canonical energy momentum tensor of the electromagnetic field. The origin of the difficulty is discussed and a covariant gauge invariant spin vector is derived. The paradox concerning the spin angular momentum of a plane wave finds a natural solution.

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Richard T. Hammond. 2017-06-18. Lorentz covariant and gauge invariant description of orbital and spin angular momentum and the non-symmetric energy momentum tensor. https://arxiv.org/abs/1706.07665

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