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arXiv · 1010.2058

Observational Constraints on Exponential Gravity

Louis Yang·Chung-Chi Lee·Ling-Wei Luo·Chao-Qiang Geng
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Abstract

We study the observational constraints on the exponential gravity model of f(R)=-beta*Rs(1-e^(-R/Rs)). We use the latest observational data including Supernova Cosmology Project (SCP) Union2 compilation, Two-Degree Field Galaxy Redshift Survey (2dFGRS), Sloan Digital Sky Survey Data Release 7 (SDSS DR7) and Seven-Year Wilkinson Microwave Anisotropy Probe (WMAP7) in our analysis. From these observations, we obtain a lower bound on the model parameter beta at 1.27 (95% CL) but no appreciable upper bound. The constraint on the present matter density parameter is 0.245< Omega_m^0<0.311 (95% CL). We also find out the best-fit value of model parameters on several cases.

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Louis Yang, Chung-Chi Lee, Ling-Wei Luo, Chao-Qiang Geng. 2010-10-11. Observational Constraints on Exponential Gravity. https://doi.org/10.1103/physrevd.82.103515

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