English

Bayesian evidence for $\alpha$-attractor dark energy models

General Relativity and Quantum Cosmology 2019-08-07 v2 Cosmology and Nongalactic Astrophysics High Energy Physics - Theory

Abstract

Dark energy models with tracker properties have gained attention due to the large range of initial conditions leading to the current value of the dark energy density parameter. A well-motivated family of these models are the so-called α\alpha-attractors, which show the late time behavior of a cosmological constant. In the present paper we perform a model-selection analysis of a variety of α\alpha-attractor potentials in comparison with a non-flat Λ\LambdaCDM model. Specifically, we compute the Bayes Factor for the L-Model, the Oscillatory Tracker Model, the Recliner Model, and the Starobinsky Model, while considering the non-flat Λ\LambdaCDM as the base model. Each model is tested through a Bayesian analysis using observations relevant to the current accelerated expansion: we employ the latest SNe Ia data, combined with cosmic clocks, the latest BOSS release of BAO data, and the Planck Compressed 2018 data. The produced Markov Chains for each model are further compared through a Bayesian evidence analysis. From the latter we conclude that the Oscillatory Tracker Model is preferred by data (even if weakly) over the non-flat Λ\LambdaCDM model. Our results also suggest at the L-model is the least favoured version of the α\alpha-attractor models considered.

Keywords

Cite

@article{arxiv.1905.00834,
  title  = {Bayesian evidence for $\alpha$-attractor dark energy models},
  author = {Francisco X. Linares Cedeño and Ariadna Montiel and Juan Carlos Hidalgo and Gabriel Germán},
  journal= {arXiv preprint arXiv:1905.00834},
  year   = {2019}
}

Comments

18 pages, 3 figures, 6 tables. Final version accepted for publication in JCAP

R2 v1 2026-06-23T08:55:25.077Z