Evolution of the fine-structure constant in runaway dilaton models

C. J. A. P. Martins; P. E. Vielzeuf; M. Martinelli; E. Calabrese; S. Pandolfi

doi:10.1016/j.physletb.2015.03.002

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arXiv · 1503.05068

Evolution of the fine-structure constant in runaway dilaton models

C. J. A. P. Martins·P. E. Vielzeuf·M. Martinelli·E. Calabrese·S. Pandolfi

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Abstract

We study the detailed evolution of the fine-structure constant $α$ in the string-inspired runaway dilaton class of models of Damour, Piazza and Veneziano. We provide constraints on this scenario using the most recent $α$ measurements and discuss ways to distinguish it from alternative models for varying $α$. For model parameters which saturate bounds from current observations, the redshift drift signal can differ considerably from that of the canonical $Λ$CDM paradigm at high redshifts. Measurements of this signal by the forthcoming European Extremely Large Telescope (E-ELT), together with more sensitive $α$ measurements, will thus dramatically constrain these scenarios.

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C. J. A. P. Martins, P. E. Vielzeuf, M. Martinelli, E. Calabrese, S. Pandolfi. 2015-03-17. Evolution of the fine-structure constant in runaway dilaton models. https://doi.org/10.1016/j.physletb.2015.03.002

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