2001/01/31 by G. W. Gibbons, Carlos Herdeiro, C. A. R. Herdeiro · 3 citations
Physics and Astronomy · #Black Holes and Theoretical Physics #Cosmology and Gravitation Theories #Noncommutative and Quantum Gravity Theories #gr-qc #hep-th
paper · pdf · doi:10.1088/0264-9381/18/9/305
published as Class.Quant.Grav.18:1677-1690,2001 · LaTeX, 15 pages
arxiv created 2001/01/31 · openalex publication_date 2001/04/06 · arxiv updated 2009/11/30 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/30
We derive a Melvin universe-type solution describing a magnetic field permeating the whole universe in gravity minimally coupled to any nonlinear electromagnetic theory, including Born-Infeld theory. For a large set of nonlinear electrodynamics theories, our solution is complete and non-singular, as long as the magnetic field is sub-critical. We examine some properties of the solution; in particular, there is a shift of the symmetry axis and a non-standard period along the orbits of the U (1) symmetry to avoid a conical singularity. We show these are consistent with the usual Dirac quantization condition for the magnetic flux. We find exact solutions describing propagation of waves in the `generalized Melvin universe' along the principal null directions of the electromagnetic field, where the Boillat and Einstein lightcone touch. By electric-magnetic duality we show that similar Melvin electric and dyonic universes can be obtained.