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arXiv · 1608.06572

Do electromagnetic waves always propagate along null geodesics?

Felipe A. Asenjo·Sergio A. Hojman
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Abstract

We find exact solutions to Maxwell equations written in terms of four-vector potentials in non--rotating, as well as in Gödel and Kerr spacetimes. We show that Maxwell equations can be reduced to two uncoupled second-order differential equations for combinations of the components of the four-vector potential. Exact electromagnetic waves solutions are written on given gravitational field backgrounds where they evolve. We find that in non--rotating spherical symmetric spacetimes, electromagnetic waves travel along null geodesics. However, electromagnetic waves on Gödel and Kerr spacetimes do not exhibit that behavior.

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Felipe A. Asenjo, Sergio A. Hojman. 2017-09-08. Do electromagnetic waves always propagate along null geodesics?. https://doi.org/10.1088/1361-6382%2Faa8b48

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