Constraints on time variation of fine structure constant from WMAP-3yr data

2007/06/11 by Petruta Stefanescu, P. Stefanescu
Physics and Astronomy · #Astrophysics and Cosmic Phenomena #Cosmology and Gravitation Theories #Neutrino Physics Research #astro-ph

paper · pdf · doi:10.1016/j.newast.2007.06.004

published as NewAstron.12:635-640,2007 · 11 pages, 3 figures; accepted for publication in New Astronomy, June 02 2007

openalex publication_date 2007/06/11 · arxiv created 2007/07/02 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/29

Abstract

This paper presents the constraints on the time variation of the fine structure constant at recombination relative to its present value, Delta_alpha = (alpha_rec-alpha₀) / alpha₀, obtained from the analysis of the WMAP-3yr Cosmic Microwave Background (CMB) data, with an additional prior on the Hubble expansion rate from HST Hubble Key Project. I found out that -0.039 < Delta_alpha < 0.010 at 95% C.L., which brings a 30% improvement to the previous limits from WMAP-1yr data. The corresponding recombination redshift, 1012 < z_rec < 1115, shows a delayed recombination epoch compared with the results from WMAP-1yr data.

Citations

• The fundamental constants and their variation: observational and theoretical status
• Looking for a varying α in the cosmic microwave background