2003/10/31 by Kazuharu Bamba, J. Yokoyama, Jun’ichi Yokoyama · 3 citations
Physics and Astronomy · #Back-reaction #Classical mechanics #Conformal map #Conformal symmetry #Cosmology and Gravitation Theories #Dilaton #Electromagnetic field #Electromagnetism #Galaxies: Formation, Evolution, Phenomena #Inflation (cosmology) #Inflaton #Magnetic field #Physics #Quantum electrodynamics #Quantum mechanics #Scale invariance #Solar and Space Plasma Dynamics #Theoretical physics #astro-ph #hep-ph
paper · pdf · doi:10.1103/physrevd.69.043507
published as Phys.Rev.D69:043507,2004 · 28 pages, 5 figures, the version accepted for publication in Phys. Rev. D; some references are added
openalex publication_date 2004/02/25 · arxiv created 2004/08/05 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
The generation of large-scale magnetic fields is studied in dilaton electromagnetism in inflationary cosmology, taking into account the dilaton's evolution throughout inflation and reheating until it is stabilized with possible entropy production. It is shown that large-scale magnetic fields with an observationally interesting strength at the present time could be generated if the conformal invariance of the Maxwell theory is broken through the coupling between the dilaton and electromagnetic fields in such a way that the resultant quantum fluctuations in the magnetic field have a nearly scale-invariant spectrum. If this condition is met, the amplitude of the generated magnetic field could be sufficiently large even in the case that a huge amount of entropy is produced with the dilution factor \ensuremath∼1024 as the dilaton decays.