Observational constraints on 3-forms dark energy

TL;DR

This paper investigates a 3-form dark energy model with a Gaussian potential, constrains it using diverse cosmological data, and finds it can alleviate the Hubble tension while remaining theoretically consistent.

Contribution

It introduces a stable, ghost-free 3-form dark energy model with a Gaussian potential and demonstrates its observational viability and potential to reduce Hubble tension.

Findings

The model increases the Hubble constant estimate from CMB and BAO data.

It remains ghost-free and perturbatively sub-dominant.

The model reduces the Hubble tension without fine-tuning.

Abstract

3-forms are natural candidates for describing the late-time accelerated expansion of the Universe, as they can inherently reproduce a positive cosmological constant when lacking an evolving potential. When such a potential is present, a 3-form field may exhibit either quintessence-like or phantom-like behaviour. In this paper, we consider a 3-form model with a Gaussian potential, which features stable, ghost-free phantom-like behaviour within its convergence region and leads to an LSBR late-time attractor. We constrain this model observationally by performing a Markov Chain Monte Carlo (MCMC) analysis employing a comprehensive cosmological dataset, including Planck PR4 cosmic microwave background (CMB) data, DESI DR1 baryon acoustic oscillation (BAO) measurements, Pantheon+ Type Ia supernovae data, low-$z$ Cepheid calibrators, and DES Y1 large-scale structure observations. We demonstrate that the 3-form model successfully increases the predicted Hubble parameter of CMB and BAO data from $67.89\pm0.36{\rm km/s/Mpc}$ of $\Lambda$CDM model to $68.29^{+0.56}_{-0.61}{\rm km/s/Mpc}$ without fine-tuning of the model parameters, thus reducing the tension with the late-time observation. Furthermore, we verify the sub-dominance of the 3-form field perturbation via both analytical and numerical analyses. Thus, the 3-form field does serve as a promising candidate of phantom-like dark energy from both theoretical and observational points of view.