2000/07/16 by Anne-Christine Davis, Konstantinos Dimopoulos, Tomislav Prokopec +2 · 11 citations
Physics and Astronomy · #Black Holes and Theoretical Physics #Cosmology and Gravitation Theories #Solar and Space Plasma Dynamics #astro-ph #gr-qc #hep-ph
paper · pdf · doi:10.1016/s0370-2693(01)00138-1
published as Phys.Lett.B501:165-172,2001; Phys.Rev.Focus10:story9,2002 · 14 pages, 3 figures. New improved figures, typos corrected
arxiv created 2000/07/16 · openalex publication_date 2001/03/01 · arxiv updated 2009/11/30 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
We show that conformal invariance of gauge fields is naturally broken in inflation, having as a consequence amplification of gauge fields. The resulting spectrum of the field strength is approximately BL ~ L^(-1), where L is the relevant coherence scale. One realisation of our scenario is scalar electrodynamics with a scalar whose mass is large enough to evade observational constraints - the obvious candidates being supersymmetric partners of the standard-model fermions. Our mechanism also leads naturally to amplification of the standard-model Z-boson field due to its coupling to the electroweak Higgs field. At preheating, the spectrum of the Z field is transferred to the hypercharge field, which remains frozen in the plasma and is converted into a magnetic field at the electroweak phase transition. With a reasonable model of field evolution one obtains a magnetic field strength of the order of 10-29 Gauss on a scale of 100 pc, the size of the largest turbulent eddy in a virialised galaxy. Resonant amplification in preheating can lead to primordial fields as large as 10-24 Gauss, consistent with the seed field required for the galactic dynamo mechanism.