Constraining uber gravity with recent observations and studying the $H_0$ problem

Abstract

This paper studies both $\Lambda$CDM and CDM models under the \"uber gravity theory, named \"u$\Lambda$CDM and \"uCDM respectively. We report bounds over their parameter phase-space using several cosmological data, in particular, the recent Pantheon+ sample. Based on the joint analysis, the best fit value of the \"uber characteristic parameter is $z_\oplus = 0.046^{+0.047}_{-0.032}$ and $z_\oplus = 1.382^{+0.020}_{-0.021}$ at 68\% confidence level for \"u$\Lambda$CDM and \"uCDM respectively. Although \"uber gravity can successfully mimics the cosmological constant, we find that the $\mathbb{H}0(z)$ diagnostic suggests the $H_0$ tension is not alleviated. Finally, both models are statistically compared with $\Lambda$CDM through the Akaike and Bayesian information criteria. Both \"uber gravity models and $\Lambda$CDM are equally preferred for most of the single samples, in particular, \"u$\Lambda$CDM is not rejected by the CMB data. However, there is strong evidence against them for the joint analysis.