English

How predictions of cosmological models depend on Hubble parameter data sets

General Relativity and Quantum Cosmology 2018-07-20 v1

Abstract

We explore recent estimations of the Hubble parameter HH depending on redshift zz, which include 31 H(z)H(z) data points measured from differential ages of galaxies and 26 data points, obtained with other methods. We describe these data together with Union 2.1 observations of Type Ia supernovae and observed parameters of baryon acoustic oscillations with 2 cosmological models: the standard cold dark matter model with the Λ\Lambda term (Λ\LambdaCDM) and the model with generalized Chaplygin gas (GCG). For these models with different sets of H(z)H(z) data we calculate two-parameter and one-parameter distributions of χ2\chi^2 functions for all observed effects, estimate optimal values of model parameters and their 1σ1\sigma errors. For both considered models the results appeared to be strongly depending on a choice of Hubble parameter data sets if we use all 57 H(z)H(z) data points or only 31 data points from differential ages. This strong dependence can be explained in connection with 4 H(z)H(z) data points with high redshifts z>2z>2.

Keywords

Cite

@article{arxiv.1807.07323,
  title  = {How predictions of cosmological models depend on Hubble parameter data sets},
  author = {G. S. Sharov and V. O. Vasiliev},
  journal= {arXiv preprint arXiv:1807.07323},
  year   = {2018}
}

Comments

15 pages, 5 figures, published in Mathematical Modelling and Geometry, http://mmg.tversu.ru

R2 v1 2026-06-23T03:07:06.837Z