2003/09/06 by G. Rocha, Roberto Trotta, R. Trotta +4 · 1 citation
Earth and Planetary Sciences · Physics and Astronomy · #Anisotropy #Astronomy #Astrophysics #Bounded function #CMB cold spot #Cosmic background radiation #Cosmic microwave background #Cosmology and Gravitation Theories #Decoupling (probability) #Epoch (astronomy) #Galaxy #Geophysics and Gravity Measurements #Mathematical analysis #Particle physics theoretical and experimental studies #Physics #Planck #Polarization (electrochemistry) #Quantum mechanics #Redshift #Reionization #astro-ph
paper · pdf · doi:10.1016/j.newar.2003.07.018
published as NewAstron.Rev.47:863-869,2003 · 6 pages, 4 figures, 3 tables, to appear in New Astronomy Reviews, Proceedings of the 2nd CMBNET workshop, 20-21 February 2003, Oxford, UK
arxiv created 2003/09/06 · openalex publication_date 2003/10/09 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
We present a summary of recent constraints on the value of the fine-structure constant at the epoch of decoupling from the recent observations made by the Wilkinson Microwave Anisotropy Probe (WMAP) satellite. Within the set of models considered, a variation of the value of α at decoupling with respect to the present-day value is now bounded to be smaller than 2% (6%) at 95% confidence level. We point out that the existence of an early reionization epoch as suggested by the above measurements will, when more accurate cosmic microwave background polarization data is available, lead to considerably tighter constraints. We find that the tightest possible constraint on α is about 0.1 % using CMB data alone--tighter constraints will require further (non-CMB) priors.