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arXiv · 1408.2788

Varying-Alpha and K-Essence

Alexander A. H. Graham
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Abstract

We introduce a model which allows the fine structure constant (alpha) to vary throughout space and time due to a coupling to a scalar field with a non-canonical kinetic structure. This provided a new extension of the Bekenstein-Sandvik-Barrow-Magueijo model of alpha variations. The background cosmology is studied in detail using dynamical systems techniques for a scalar field of ghost condensate type. We show generically that if the kinetic terms are chosen to allow an accelerated late-time attractor for the expansion scale factor then alpha will not asymptote to a constant at late times.

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Alexander A. H. Graham. 2014-08-12. Varying-Alpha and K-Essence. https://doi.org/10.1088/0264-9381/32/1/015019

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