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arXiv · 2306.16445

Double Kerr-Schild spacetimes and the Newman-Penrose map

Kara Farnsworth·Michael Graesser·Gabriel Herczeg
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Abstract

The Newman-Penrose map, which is closely related to the classical double copy, associates certain exact solutions of Einstein's equations with self-dual solutions of the vacuum Maxwell equations. Here we initiate an extension of the Newman-Penrose map to a broader class of spacetimes. As an example, we apply principles from the Newman-Penrose map to associate a self-dual gauge field to the Kerr-Taub-NUT-(A)dS spacetime and we show that the result agrees with previously studied examples of classical double copies. The corresponding field strength exhibits a discrete electric-magnetic duality that is distinct from its (Hodge star) self-dual property.

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Kara Farnsworth, Michael Graesser, Gabriel Herczeg. 2023-06-28. Double Kerr-Schild spacetimes and the Newman-Penrose map. https://arxiv.org/abs/2306.16445

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