2009/07/31 by Jose Beltran Jimenez, Tomi S. Koivisto, Antonio L. Maroto +1 · 1 citation
Physics and Astronomy · #physics.gen-ph #gr-qc
paper · pdf · doi:10.1088/1475-7516/2009/10/029
published as JCAP 0910:029,2009 · 12 pages, 3 figures. Added new comments to match the published version
arxiv created 2009/11/03 · arxiv updated 2009/12/01
It has been recently proposed that the presence of a temporal electromagnetic field on cosmological scales could explain the phase of accelerated expansion that the universe is currently undergoing. The field contributes as a cosmological constant and therefore, the homogeneous cosmology produced by such a model is exactly the same as that of ΛCDM. However, unlike a cosmological constant term, electromagnetic fields can acquire perturbations which in principle could affect CMB anisotropies and structure formation. In this work, we study the evolution of inhomogeneous scalar perturbations in this model. We show that provided the initial electromagnetic fluctuations generated during inflation are small, the model is perfectly compatible with both CMB and large scale structure observations at the same level of accuracy as ΛCDM.