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

TL;DR

This study constrains 'uber gravity' models using recent cosmological data, finds they mimic dark energy but do not resolve the H0 tension, and compares their statistical fit to the standard Lambda CDM model.

Contribution

It provides new bounds on 'uber gravity' parameters using recent observations and assesses their viability in explaining cosmic acceleration and the H0 tension.

Findings

'uber gravity' models fit data similarly to Lambda CDM for single samples.

'uΛCDM' is not rejected by CMB data.

'uber gravity' does not resolve the H0 tension.

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.