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Extra Dimensions and Varying Alpha

C. J. A. P. Martins
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Abstract

I review recent constraints on and claimed detections of a time-varying fine-structure constant $α$. Our results are consistent with no variation in $α$ from the epoch of recombination to the present day, and restrict any such variation to be less than about 4%. The forthcoming MAP and Planck experiments will be able to break most of the currently existing degeneracies between $α$ and other cosmological parameters, and measure $α$ in the early universe with an accuracy comparable to current claimed recent-universe detections.

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C. J. A. P. Martins. 2002-07-05. Extra Dimensions and Varying Alpha. https://arxiv.org/abs/hep-ph/0207090

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