2025/02/26 by Robert Brandenberger, Jürg Fröhlich, Brandenberger, Robert +3 · 4 citations
Physics and Astronomy · #Cosmology and Gravitation Theories #Cosmology and Nongalactic Astrophysics (astro-ph.CO) #Dark Matter and Cosmic Phenomena #FOS: Physical sciences #General Relativity and Quantum Cosmology (gr-qc) #High Energy Physics - Phenomenology (hep-ph) #High Energy Physics - Theory (hep-th) #Quantum and Classical Electrodynamics
paper · pdf · doi:10.48550/arxiv.2502.19310
openalex publication_date 2025/02/26 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
We propose a mechanism for the generation of magnetic fields on cosmological scales that is operative after recombination. An essential ingredient is an instability (of parametric resonance type) of the electromagnetic field driven by an oscillating pseudo-scalar dark matter field, ϕ, that is coupled to the electromagnetic field tensor via a ϕF \wedge F term in the Lagrangian of axion-electrodynamics. We find that magnetic fields larger than the observational lower bounds can be generated soon after recombination on scales of 1 \rmMpc.