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arXiv · astro-ph/0306047

Varying Alpha in a More Realistic Universe

D. F. Mota·J. D. Barrow
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Abstract

We study the space-time evolution of the fine structure constant, $α$, inside evolving spherical overdensities in a lambda-CDM Friedmann universe using the spherical infall model. We show that its value inside virialised regions will be significantly larger than in the low-density background universe. The consideration of the inhomogeneous evolution of the universe is therefore essential for a correct comparison of extragalactic and solar system limits on, and observations of, possible time variation in $α$ and other constants. Time variation in $α$ in the cosmological background can give rise to no locally observable variations inside virialised overdensities like the one in which we live, explaining the discrepancy between astrophysical and geochemical observations.

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D. F. Mota, J. D. Barrow. 2003-12-09. Varying Alpha in a More Realistic Universe. https://doi.org/10.1016/j.physletb.2003.12.016

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