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arXiv · 1006.1842

Equivalence Principle (EP) and Solar System Constraints on $R(1\pm ε\ln({R \over R_c}))$ model of Gravity

Kh. Saaidi·A. Aghamohammadi
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Abstract

Experiments on the violation of equivalence principle (EP) and solar system give a number of constraints in which any modified gravity model must satisfy them. We study these constraints on a kind of $f(R)$ gravity as $f(R) = R(1\pm ε\ln({R \over R_c}))$. For this investigation we use of chameleon mechanism and show that a spherically body has thin-shell in this model. So that we obtain an effective coupling of the fifth force which is suppressed through a chameleon mechanism. Also, we obtain $γ_{PPN} = 1 \pm 1.13 \times10^{-5}$ which is agreement with experiment results. At last, we show that for $R_c \thickapprox ρ_c$ this model is consistent with EP, thin shell condition and fifth force of chameleon mechanism for $ε\backsimeq 10^{-14}$.

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Kh. Saaidi, A. Aghamohammadi. 2011-01-18. Equivalence Principle (EP) and Solar System Constraints on $R(1\pm ε\ln({R \over R_c}))$ model of Gravity. https://doi.org/10.1007/s10509-011-0621-1

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