Abstract
We demonstrate that recent measurements of cosmic microwave background temperature and polarization anisotropy made by the ACBAR, QUAD, and BICEP experiments substantially improve the cosmological constraints on possible variations of the fine structure constant in the early universe. This data, combined with the five year observations from the WMAP mission, yield the constraint at 68% C.L. The inclusion of the new Hubble Space Telescope constraints on the Hubble constant further increases the accuracy to at 68% C.L., bringing possible deviations from the current value below the 1% level and improving previous constraints by a factor of .
- Received 22 September 2009
DOI:https://doi.org/10.1103/PhysRevD.80.087302
©2009 American Physical Society