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arXiv · 1011.0508

Equation of state for dark energy in $f(T)$ gravity

Kazuharu Bamba·Chao-Qiang Geng·Chung-Chi Lee·Ling-Wei Luo
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Abstract

We study the cosmological evolutions of the equation of state for dark energy $w_{\mathrm{DE}}$ in the exponential and logarithmic as well as their combination $f(T)$ theories. We show that the crossing of the phantom divide line of $w_{\mathrm{DE}} = -1$ can be realized in the combined $f(T)$ theory even though it cannot be in the exponential or logarithmic $f(T)$ theory. In particular, the crossing is from $w_{\mathrm{DE}} > -1$ to $w_{\mathrm{DE}} < -1$, in the opposite manner from $f(R)$ gravity models. We also demonstrate that this feature is favored by the recent observational data.

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Kazuharu Bamba, Chao-Qiang Geng, Chung-Chi Lee, Ling-Wei Luo. 2010-11-02. Equation of state for dark energy in $f(T)$ gravity. https://doi.org/10.1088/1475-7516/2011/01/021

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