Is there a dynamical tendency in H0 with late time measurements?

TL;DR

This study investigates whether a dynamical evolution of the Hubble constant exists within late-time measurements across different redshifts, revealing potential variations that could impact the understanding of the Hubble tension.

Contribution

It introduces a novel analysis of late-time H0 measurements across redshift bins, suggesting possible redshift-dependent evolution of H0 within late-time data.

Findings

Evidence of H0 variation across redshift bins with up to 2.3σ significance.

Indication that Hubble tension may exist within late-time measurements themselves.

Challenges the assumption of a constant H0 in the FLRW cosmological model.

Abstract

The discrepancy between the Hubble constant $H_0$ values derived from early-time and late-time measurements, reaching up to $4\sigma$, represents the most serious challenge in modern cosmology and astrophysics. In this work, we investigate if a similar tension exists between only late time measurements at different redshifts. We use the latest public datasets including Cosmic Chronometers, Megamasers, SNe Ia and DESI-BAO, that span from redshift $z \sim 0$ up to $z\sim 2.3$. By dividing the data into redshift bins, we derive $H_0$ values from each bin separately. Our analysis reveals a phenomenological dynamic evolution in $H_0$ across different redshift ranges, with a significance from $1.5\sigma$ and $2.3\sigma$, depending on the parameterization. Consistency of the model demands observational constancy of $H_0$ since it is an integration constant within the Friedmann-Lema\^itre-Robertson-Walker (FLRW) metric. Thus, these findings suggest that the observed Hubble tension might not only exist between early and late-time measurements but also among late-time data themselves, providing new insights into the nature of the Hubble tension.