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arXiv · 1806.05835

Universal electromagnetic fields

Sigbjørn Hervik·Marcello Ortaggio·Vojtěch Pravda
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Abstract

We study universal electromagnetic (test) fields, i.e., p-forms fields F that solve simultaneously (virtually) any generalized electrodynamics (containing arbitrary powers and derivatives of F in the field equations) in n spacetime dimensions. One of the main results is a sufficient condition: any null F that solves Maxwell's equations in a Kundt spacetime of aligned Weyl and traceless-Ricci type III is universal (in particular thus providing examples of p-form Galileons on curved Kundt backgrounds). In addition, a few examples in Kundt spacetimes of Weyl type II are presented. Some necessary conditions are also obtained, which are particularly strong in the case n=4=2p: all the scalar invariants of a universal 2-form in four dimensions must be constant, and vanish in the special case of a null F .

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Sigbjørn Hervik, Marcello Ortaggio, Vojtěch Pravda. 2018-06-15. Universal electromagnetic fields. https://doi.org/10.1088/1361-6382%2Faad13d

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