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arXiv · 1212.6815

Constraints on thawing scalar field models from fundamental constants

Qing Gao·Yungui Gong
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Abstract

We consider a dark energy model with a relation between the equation of state parameter $w$ and the energy density parameter $Ω_ϕ$ derived from thawing scalar field models. Assuming the variation of the fine structure constant is caused by dark energy, we use the observational data of the variation of the fine structure constant to constrain the current value of $w_0$ and $Ω_{ϕ0}$ for the dark energy model. At the $1σ$ level, the observational data excluded some areas around $w_0=-1$, which explains the positive detection of the variation of the fine structure constant at the $1σ$ level, but $Λ$CDM model is consistent with the data at the $2σ$ level.

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Qing Gao, Yungui Gong. 2013-03-12. Constraints on thawing scalar field models from fundamental constants. https://doi.org/10.1142/s0218271813500351

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