Constraining the curvature density parameter in cosmology

The cosmic curvature density parameter has been constrained in the present work independent of any background cosmological model. The reconstruction is undertaken adopting the nonparametric Gaussian processes (GP). The constraints on Omega(k0) are obtained via a Markov Chain Monte Carlo (MCMC) analysis. Late-time cosmological probes viz., the supernova (SN) distance modulus data, the cosmic chronometer (CC) and the radial baryon acoustic oscillations (rBAO) measurements of the Hubble data have been utilized for this purpose. The results are further combined with the data from redshift space distortions (RSD) which studies the growth of large scale structure in the universe. The only a priori assumption is that the universe is homogeneous and isotropic, described by the Friedmann-Lemattre-Robertson-Walker metric. Results indicate that a spatially flat universe is well consistent in 2 sigma within the domain of reconstruction 0 < z < 2 for the background data. On combining the RSD data we find that the results obtained are consistent with spatial flatness mostly within 2 sigma and always within 3 sigma in the domain of reconstruction 0 < z < 2.

Automated summary

The cosmic curvature density parameter has been constrained independent of any background cosmological model using nonparametric Gaussian processes. Multiple cosmological probes were utilized to analyze the data, and the results indicate that the spatial flatness of the universe is consistent with the observed data.