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arXiv · 1910.11021

A class of solitons in Maxwell-scalar and Einstein-Maxwell-scalar models

Carlos A. R. Herdeiro·João M. S. Oliveira·Eugen Radu
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Abstract

Recently, no-go theorems for the existence of solitonic solutions in Einstein-Maxwell-scalar (EMS) models have been established in arXiv:1902.07721. Here we discuss how these theorems can be circumvented by a specific class of non-minimal coupling functions between a real, canonical scalar field and the electromagnetic field. When the non-minimal coupling function diverges in a specific way near the location of a point charge, it regularises all physical quantities yielding an everywhere regular, localised lump of energy. Such solutions are possible even in flat spacetime Maxwell-scalar models, wherein the model is fully integrable in the spherical sector, and exact solutions can be obtained, yielding an explicit mechanism to de-singularise the Coulomb field. Considering their gravitational backreaction, the corresponding (numerical) EMS solitons provide a simple example of self-gravitating, localised energy lumps.

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Carlos A. R. Herdeiro, João M. S. Oliveira, Eugen Radu. 2019-10-24. A class of solitons in Maxwell-scalar and Einstein-Maxwell-scalar models. https://doi.org/10.1140/epjc%2Fs10052-019-7583-9

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