A combined analysis of the $H_0$ late time direct measurements and the impact on the Dark Energy sector

TL;DR

This paper combines multiple local measurements of the Hubble constant, finds significant tension with the standard cosmological model, and explores implications for dark energy properties, providing evidence for physics beyond the Lambda-CDM model.

Contribution

It offers a comprehensive combined H_0 estimate from diverse methods and assesses its impact on extended dark energy models, revealing strong evidence for new physics.

Findings

H_0=72.94±0.75 km/s/Mpc from combined data

Strong evidence (>4.9σ) for phantom dark energy in wCDM

Evidence (>5.7σ) for dark matter-dark energy coupling in IDE

Abstract

We combine 23 Hubble constant measurements based on Cepheids-SN Ia, TRGB-SN Ia, Miras-SN Ia, Masers, Tully Fisher, Surface Brightness Fluctuations, SN II, Time-delay Lensing, Standard Sirens and $\gamma$-ray Attenuation, obtaining our best {\it optimistic} $H_0$ estimate, that is $H_0=72.94\pm0.75$ km/s/Mpc at 68\% CL. This is in $5.9\sigma$ tension with the $\Lambda$CDM model, therefore we evaluate its impact on the extended Dark Energy cosmological models that can alleviate the tension. We find more than $4.9\sigma$ evidence for a phantom Dark Energy equation of state in the $w$CDM scenario, the cosmological constant ruled out at more than $3\sigma$ in a $w_0w_a$CDM model and more than $5.7\sigma$ evidence for a coupling between Dark Matter and Dark Energy in the IDE scenario. Finally, we check the robustness of our results, and we quote two additional combinations of the Hubble constant. The {\it ultra-conservative} estimate, $H_0=72.7\pm 1.1$ km/s/Mpc at 68\% CL, is obtained removing the Cepheids-SN Ia and the Time-Delay Lensing based measurements, and confirms the evidence for new physics.