Multi-axion like description of the dark sector in light of the Hubble and $\sigma_8$ tensions

TL;DR

This paper proposes a multi-axion-like model of the dark sector that addresses the Hubble and 8 tensions by introducing coupled axion fields, achieving consistency with key cosmological observations.

Contribution

It introduces a novel multi-axion-like dark sector model that simultaneously resolves the Hubble and 8 tensions while aligning with observational data.

Findings

The model eliminates both Hubble and 8 tensions.

It remains consistent with DESI survey data.

It fits the BAO sound horizon measurements.

Abstract

Local methods of direct determination of the Hubble constant and $\sigma_8$ seem to conflict with the predictions made from the cosmic microwave background and $\Lambda$CDM. We propose a proof-of-concept model that models portions of the dark sector as several coupled axion-like fields, resulting in both early and late time departures from $\Lambda$CDM. We determine that the model successfully eliminates both the Hubble and $\sigma_8$ tensions, while remaining consistent with both the DESI survey and the BAO sound horizon.