https://doi.org/10.1140/epjc/s10052-023-11969-y
Regular Article - Theoretical Physics
Geodesic completeness of effective null geodesics in regular space-times with non-linear electrodynamics
1
Departamento de Física Teórica and IPARCOS, Universidad Complutense de Madrid, 28040, Madrid, Spain
2
Departamento de Física Teórica and IFIC, Centro Mixto Universidad de Valencia-CSIC, Universidad de Valencia, Burjassot, 46100, Valencia, Spain
3
Departamento de Física, Universidade Federal do Ceará (UFC), C.P. 6030, Campus do Pici, 60455-760, Fortaleza, CE, Brazil
Received:
17
April
2023
Accepted:
25
August
2023
Published online:
5
September
2023
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.
© The Author(s) 2023
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