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arXiv · 1506.03253

Constraints on the Combined Models with $R^{2-q}$ Inflation and Viable $f(R)$ Dark Energy

Chao-Qiang Geng·Chung-Chi Lee·Shan Lin
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Abstract

We investigate the observational constraints on the modified gravity, which combines the $R^{2-q}$ inflation with the power-law (exponential) type of the viable $f(R)$ dark energy models. We discuss the difference between the combined model and $R^{2-q}$ gravity in the inflationary epoch and obtain the constraints on the deviation power $q$ as well as the parameters in $f(R)$ by using the CosmoMC package. The allowed ranges of the spectral index and tensor-to-scalar ratio from the Planck data are highly restricted, resulting in $q < 2.66 \times 10^{-2}$ and $2.17 \times 10^{-2}$ for the power-law and exponential types of $f(R)$ gravity, respectively.

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Chao-Qiang Geng, Chung-Chi Lee, Shan Lin. 2015-06-10. Constraints on the Combined Models with $R^{2-q}$ Inflation and Viable $f(R)$ Dark Energy. https://doi.org/10.1007/s10509-015-2535-9

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