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arXiv · 1407.5405

Parameters of cosmological models and recent astronomical observations

G. S. Sharov·E. G. Vorontsova
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Abstract

For different gravitational models we consider limitations on their parameters coming from recent observational data for type Ia supernovae, baryon acoustic oscillations, and from 34 data points for the Hubble parameter $H(z)$ depending on redshift. We calculate parameters of 3 models describing accelerated expansion of the universe: the $Λ$CDM model, the model with generalized Chaplygin gas (GCG) and the multidimensional model of I. Pahwa, D.~Choudhury and T.R.~Seshadri. In particular, for the $Λ$CDM model $1σ$ estimates of parameters are: $H_0=70.262\pm0.319$ km\,c${}^{-1}$Mpc${}^{-1}$, $Ω_m=0.276_{-0.008}^{+0.009}$, $Ω_Λ=0.769\pm0.029$, $Ω_k=-0.045\pm0.032$. The GCG model under restriction $α\ge0$ is reduced to the $Λ$CDM model. Predictions of the multidimensional model essentially depend on 3 data points for $H(z)$ with $z\ge2.3$.

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G. S. Sharov, E. G. Vorontsova. 2014-07-21. Parameters of cosmological models and recent astronomical observations. https://doi.org/10.1088/1475-7516%2F2014%2F10%2F057

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