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Time variation of proton-electron mass ratio and fine structure constant with runaway dilaton

Takeshi Chiba·Tatsuo Kobayashi·Masahide Yamaguchi·Jun'ichi Yokoyama
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Abstract

Recent astrophysical observations indicate that the proton-electron mass ratio and the fine structure constant have gone through nontrivial time evolution. We discuss their time variation in the context of a dilaton runaway scenario with gauge coupling unification at the string scale $M_{\rm s}$. We show that the choice of adjustable parameters allows them to fit the same order magnitude of both variations and their (opposite) signs in such a scenario.

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Takeshi Chiba, Tatsuo Kobayashi, Masahide Yamaguchi, Jun'ichi Yokoyama. 2007-02-14. Time variation of proton-electron mass ratio and fine structure constant with runaway dilaton. https://doi.org/10.1103/physrevd.75.043516

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