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arXiv · 1912.02177

The Classical Double Copy of a Point Charge

Kwangeon Kim·Kanghoon Lee·Ricardo Monteiro·Isobel Nicholson·David Peinador Veiga
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Abstract

The classical double copy relates solutions to the equations of motion in gauge theory and in gravity. In this paper, we present two double-copy formalisms for relating the Coulomb solution in gauge theory to the two-parameter Janis-Newman-Winicour solution in gravity. The latter is a static, spherically symmetric, asymptotically flat solution that generically includes a dilaton field, but also admits the Schwarzschild solution as a special case. We first present the classical double copy as a perturbative construction, similar to its formulation for scattering amplitudes, and then present it as an exact map, with a novel generalisation of the Kerr-Schild double copy motivated by double field theory. The latter formalism exhibits the relation between the Kerr-Schild classical double copy and the string theory origin of the double copy for scattering amplitudes.

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Kwangeon Kim, Kanghoon Lee, Ricardo Monteiro, Isobel Nicholson, David Peinador Veiga. 2019-12-04. The Classical Double Copy of a Point Charge. https://doi.org/10.1007/jhep02(2020)046

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