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arXiv · 1305.7333

Revisiting the matter power spectra in $f(R)$ gravity

Jian-hua He·Baojiu Li·Yipeng Jing
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Abstract

In this paper, we study the non-linear matter power spectrum in a specific family of $f(R)$ models that can reproduce the $Λ$CDM background expansion history, using high resolution $N$-body simulations based on the {\sc ecosmog} code. We measure the matter power spectrum in the range of $0.05h{\rm Mpc}^{-1} 10^{-3}$, we find no chameleon screening in dense regions at late times ($z<3$), which means that those models could be ruled out due to the factor-of-$1/3$ enhancement to the strength of Newtonian gravity. We also give the best-fit parameters for a generalised PPF fitting formula which works well for the models studied here.

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Jian-hua He, Baojiu Li, Yipeng Jing. 2013-10-28. Revisiting the matter power spectra in $f(R)$ gravity. https://doi.org/10.1103/physrevd.88.103507

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