Exploring Hubble Tension Alleviation through Neutrino-Coupled Perturbed $f(R)$ Gravity

TL;DR

This study investigates whether perturbed f(R) gravity models, especially when coupled with neutrinos, can reduce the discrepancy between early and late universe measurements of the Hubble constant using recent observational data.

Contribution

It introduces and compares perturbed f(R) gravity models with and without neutrino coupling, demonstrating that neutrino interactions help alleviate the Hubble tension.

Findings

Neutrino coupling shifts H0 towards higher values.

Coupled f(R) gravity reduces residual Hubble tension.

Models with neutrinos align better with local and CMB data.

Abstract

This work examines the Hubble constant (\(H_0\)) tension within the frameworks of perturbed \(f(R)\) gravity and perturbed \(f(R)\) gravity coupled with neutrinos, using lastest observational data. The datasets incorporate the Cosmic Microwave Background (CMB), Baryon Acoustic Oscillations (BAO), Cosmic Chronometers (CC), lensing, and Pantheon supernovae. We compare the ability of these models to bridge the discrepancy between Planck 2018 (\(H_0 = 67.4 \pm 0.5 \ \text{km/s/Mpc}\)) and the local R22 measurement (\(H_0 = 73.5 \pm 1.04 \ \text{km/s/Mpc}\)). In perturbed \(f(R)\) gravity, the derived \(H_0\) values align closely with Planck, leaving a substantial tension with R22. The inclusion of neutrino interactions introduces additional parameters that shift \(H_0\) toward higher values, reducing the tension with local measurements. Notably, the coupled model achieves a smaller residual tension compared to the standalone perturbed \(f(R)\) model, indicating that neutrino physics plays a significant role in modifying the late-time expansion dynamics. While both models provide insights into addressing the Hubble tension, the coupled \(f(R)\) gravity with neutrinos offers a more consistent alignment across the datasets.