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

Abstract

This paper studies both $\hat{I}›$CDM and CDM models under the über gravity theory, named ü$\hat{I}›$CDM and üCDM 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 über characteristic parameter is $z_{\oplus }=0.046_{-0.032}^{+0.047}$ and $z_{\oplus }=1.382_{-0.021}^{+0.020}$ at 68\% confidence level for ü$\hat{I}›$CDM and üCDM respectively. Although über 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 $\hat{I}›$CDM through the Akaike and Bayesian information criteria. Both über gravity models and $\hat{I}›$CDM are equally preferred for most of the single samples, in particular, ü$\hat{I}›$CDM is not rejected by the CMB data. However, there is strong evidence against them for the joint analysis.

11 pages, 4 figures, accepted in EPJC