Exploring the Hubble Tension: A Novel Approach through Cosmological Observations

TL;DR

This paper proposes a new cosmological model with a redshift-dependent energy component to resolve the Hubble tension, achieving consistency between early and late universe measurements.

Contribution

It introduces a variable energy source with a specific redshift dependence as a novel approach to address the Hubble tension in cosmology.

Findings

The model aligns the Hubble constant with local measurements.

It remains consistent with BAO data.

Suggests a non-zero curvature density parameter.

Abstract

The simplest cosmological model ($\Lambda$CDM) is well-known to suffer from the Hubble tension, namely an almost $5 \sigma$ discrepancy between the (model-based) early-time determination of the Hubble constant $H_0$ and its late-time (and model-independent) determination. To circumvent this, we introduce an additional energy source that varies with the redshift as $(1 + z)^n$, where $0 < n < 3$, and test it against the Pantheon Compilation of Type Ia Supernovae as well as the CMBR observations (at $z \approx 1100$). The deduced $H_0$ is now well-consistent with the value obtained from local observations of Cepheid variables. Suggesting a non-zero value for the curvature density parameter, positive (negative) for $n > 2$ ($n < 2$), the resolution is also consistent with the BAO data.