Running Hubble constant from the SNe Ia Pantheon sample?
Abstract
The mismatch between different independent measurements of the expansion rate of the Universe is known as the Hubble constant () tension, and it is a serious and pressing problem in cosmology. We investigate this tension considering the dataset from the Pantheon sample, a collection of 1048 Type Ia Supernovae (SNe Ia) with a redshift range . We perform a binned analysis in redshift to study if the tension also occurs in SNe Ia data. Hence, we build equally populated subsamples in three and four bins, and we estimate in each bin considering the CDM and CDM cosmological models. We perform a statistical analysis via a Markov Chain Monte Carlo (MCMC) method for each bin. We observe that evolves with the redshift, using a fit function with two fitting parameters and . Our results show a decreasing behavior of with and a consistency with no evolution between 1.2 and 2.0 . Considering the tension, we extrapolate until the redshift of the last scattering surface, , obtaining values of consistent in 1 with the cosmic microwave background (CMB) measurements by Planck. Finally, we discuss possible modified gravity models to explain a running Hubble constant with the redshift, and we infer the form of the scalar field potential in the dynamically equivalent Jordan frame.
Cite
@article{arxiv.2205.07033,
title = {Running Hubble constant from the SNe Ia Pantheon sample?},
author = {Tiziano Schiavone and Giovanni Montani and Maria Giovanna Dainotti and Biagio De Simone and Enrico Rinaldi and Gaetano Lambiase},
journal= {arXiv preprint arXiv:2205.07033},
year = {2022}
}
Comments
9 pages, 2 figures, 1 table, Proceedings of the 17th Italian-Korean Symposium on Relativistic Astrophysics, August 2-6, 2021. It is based on arXiv:2103.02117 and arXiv:2201.09848