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arXiv · 1106.0102

$f(T)$ Theories and Varying Fine Structure Constant

Hao Wei·Xiao-Peng Ma·Hao-Yu Qi
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Abstract

In analogy to $f(R)$ theory, recently a new modified gravity theory, namely the so-called $f(T)$ theory, has been proposed to drive the current accelerated expansion without invoking dark energy. In the present work, by extending Bisabr's idea, we try to constrain $f(T)$ theories with the varying fine structure "constant", $\alpha\equiv e^2/\hbar c$. We find that the constraints on $f(T)$ theories from the observational $\Delta\alpha/\alpha$ data are very severe. In fact, they make $f(T)$ theories almost indistinguishable from $\Lambda$CDM model.

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Hao Wei, Xiao-Peng Ma, Hao-Yu Qi. 2011-06-01. $f(T)$ Theories and Varying Fine Structure Constant. https://doi.org/10.1016/j.physletb.2011.07.042

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