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arXiv · 2304.05852

Geodesic completeness of effective null geodesics in regular space-times with non-linear electrodynamics

Merce Guerrero·Gonzalo J. Olmo·Diego Rubiera-Garcia
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Abstract

We study the completeness of light trajectories in certain spherically symmetric regular geometries found in Palatini theories of gravity threaded by non-linear (electromagnetic) fields, which makes their propagation to happen along geodesics of an effective metric. Two types of geodesic restoration mechanisms are employed: by pushing the focal point to infinite affine distance, thus unreachable in finite time by any sets of geodesics, or by the presence of a defocusing surface associated to the development of a wormhole throat. We discuss several examples of such geometries to conclude the completeness of all such effective paths. Our results are of interest both for the finding of singularity-free solutions and for the analysis of their optical appearances e.g. in shadow observations.

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Merce Guerrero, Gonzalo J. Olmo, Diego Rubiera-Garcia. 2023-04-12. Geodesic completeness of effective null geodesics in regular space-times with non-linear electrodynamics. https://doi.org/10.1140/epjc%2Fs10052-023-11969-y

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