Parameters of cosmological models and recent astronomical observations

TL;DR

This paper constrains parameters of three cosmological models using recent astronomical data, providing updated estimates for key parameters and analyzing model dependencies on observational inputs.

Contribution

It offers new parameter estimates for the $ ext{Lambda}$CDM, GCG, and multidimensional models based on recent observational data, highlighting model sensitivities.

Findings

$ ext{Lambda}$CDM parameters estimated with high precision.

GCG model reduces to $ ext{Lambda}$CDM under certain conditions.

Multidimensional model predictions depend heavily on high-redshift data points.

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 $\Lambda$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 $\Lambda$CDM model $1\sigma$ estimates of parameters are: $H_0=70.262\pm0.319$ km\,c${}^{-1}$Mpc${}^{-1}$, $\Omega_m=0.276_{-0.008}^{+0.009}$, $\Omega_\Lambda=0.769\pm0.029$, $\Omega_k=-0.045\pm0.032$. The GCG model under restriction $\alpha\ge0$ is reduced to the $\Lambda$CDM model. Predictions of the multidimensional model essentially depend on 3 data points for $H(z)$ with $z\ge2.3$.