Abstract
Higher-dimensional theories have the remarkable feature of predicting a time (and hence redshift) dependence of the “fundamental” four dimensional constants on cosmological time scales. In this paper, we update the bounds on a possible variation of the fine structure constant at the time of big bang nucleosynthesis and cosmic microwave background (CMB) Using the recently released high-resolution CMB anisotropy data and the latest estimates of primordial abundances of and D, we do not find evidence for a varying α at more than a one-sigma level at either epoch.
- Received 21 February 2001
DOI:https://doi.org/10.1103/PhysRevD.64.103505
©2001 American Physical Society