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Time Evolution of the Fine Structure Constant in a Two-Field Quintessence Model

M. C. Bento·O. Bertolami·N. M. C. Santos
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Abstract

We examine the variation of the fine structure constant in the context of a two-field quintessence model. We find that, for solutions that lead to a transient late period of accelerated expansion, it is possible to fit the data arising from quasar spectra and comply with the bounds on the variation of $α$ from the Oklo reactor, meteorite analysis, atomic clock measurements, Cosmic Microwave Background Radiation and Big Bang Nucleosynthesis. That is more difficult if we consider solutions corresponding to a late period of permanent accelerated expansion.

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M. C. Bento, O. Bertolami, N. M. C. Santos. 2004-05-28. Time Evolution of the Fine Structure Constant in a Two-Field Quintessence Model. https://doi.org/10.1103/physrevd.70.107304

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