English

Emergent Unparticles Dark Energy can restore cosmological concordance

Cosmology and Nongalactic Astrophysics 2023-02-02 v1 General Relativity and Quantum Cosmology High Energy Physics - Phenomenology High Energy Physics - Theory

Abstract

Addressing the discrepancy between the late and early time measurements of the Hubble parameter, H0H_0, and the so-called S8S_8 parameter has been a challenge in precision cosmology. Several models are present to address these tensions, but very few of them can do so simultaneously. In the past, we have suggested Banks-Zaks/Unparticles as an emergent Dark Energy model and claimed that it can ameliorate the Hubble tension. In this work, we test this claim and perform a likelihood analysis of the model and its parameters are given current data and compare it to Λ\LambdaCDM. The model offers a possible resolution of Hubble tension and softens the Large Scale Structure (LSS) tension without employing a scalar field or modifying the gravitational sector. Our analysis shows a higher value of H07073H_0 \sim 70 - 73 km/sec/Mpc and a slightly lower value of S8S_8 for various combinations of data sets. Consideration of Planck CMB data combined with the Pantheon sample and SH0ES priors lowers the H0H_0 and S8S_8 tension to 0.96σ0.96 \sigma and 0.94σ0.94 \sigma respectively with best-fit Δχ210\Delta \chi^2 \approx -10 restoring cosmological concordance. Significant improvement in the likelihood persists for other combinations of data sets as well. Evidence for the model is given by inferring one of its parameters to be x04.36x_0\simeq-4.36.

Keywords

Cite

@article{arxiv.2302.00067,
  title  = {Emergent Unparticles Dark Energy can restore cosmological concordance},
  author = {Ido Ben-Dayan and Utkarsh Kumar},
  journal= {arXiv preprint arXiv:2302.00067},
  year   = {2023}
}

Comments

32 pages, 7 Tables, 12 Figures