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arXiv · gr-qc/0212017

Varying Fine-Structure Constant and the Cosmological Constant Problem

Yasunori Fujii
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Abstract

We start with a brief account of the latest analysis of the Oklo phenomenon providing the still most stringent constraint on time-variability of the fine- structure constant $α$. Comparing this with the recent result from the measurement of distant QSO's appears to indicate a non-uniform time-dependence, which we argue to be related to another recent finding of the accelerating universe. This view is implemented in terms of the scalar-tensor theory, applied specifically to the small but nonzero cosmological constant. Our detailed calculation shows that these two phenomena can be understood in terms of a common origin, a particular behavior of the scalar field, dilaton. We also sketch how this theoretical approach makes it appropriate to revisit non- Newtonian gravity featuring small violation of Weak Equivalence Principle at medium distances.

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Yasunori Fujii. 2002-12-12. Varying Fine-Structure Constant and the Cosmological Constant Problem. https://doi.org/10.1023/a%3A1022566431460

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