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

**Authors:** Francisco X. Linares Cede\~no, Ariadna Montiel, Juan Carlos Hidalgo,, Gabriel Germ\'an

arXiv: 1905.00834 · 2019-08-07

## TL;DR

This paper evaluates various $oldsymbol{	extalpha}$-attractor dark energy models using Bayesian evidence with recent cosmological data, finding the Oscillatory Tracker Model slightly preferred over the non-flat $oldsymbol{	extLambda}$CDM model.

## Contribution

It provides a Bayesian model-selection analysis of multiple $oldsymbol{	extalpha}$-attractor potentials against non-flat $oldsymbol{	extLambda}$CDM using comprehensive observational data.

## Key findings

- Oscillatory Tracker Model is weakly preferred over non-flat $oldsymbol{	extLambda}$CDM.
- L-model is the least favored among the considered $oldsymbol{	extalpha}$-attractor models.
- Bayesian evidence analysis supports the viability of certain $oldsymbol{	extalpha}$-attractor models.

## 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 $\alpha$-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 $\alpha$-attractor potentials in comparison with a non-flat $\Lambda$CDM 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 $\Lambda$CDM 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 $\Lambda$CDM model. Our results also suggest at the L-model is the least favoured version of the $\alpha$-attractor models considered.

## Full text

_Full body text omitted from this summary view._ Fetch the complete paper as Markdown: https://tomesphere.com/paper/1905.00834/full.md

## Figures

5 figures with captions in the complete paper: https://tomesphere.com/paper/1905.00834/full.md

## References

105 references — full list in the complete paper: https://tomesphere.com/paper/1905.00834/full.md

---
Source: https://tomesphere.com/paper/1905.00834