Thawing Quintessence: Priors, evidence, and likely trajectories

Fuente: arXiv
Gespeichert in:
Bibliographische Detailangaben
1. Verfasser: Shlivko, David
Format: Preprint
Veröffentlicht: 2025
Schlagworte:
Online-Zugang:
Tags: Tag hinzufügen
Keine Tags, Fügen Sie den ersten Tag hinzu!
_version_ 1866908977342709760
author Shlivko, David
author_facet Shlivko, David
contents We perform a Bayesian comparison between thawing quintessence and a cosmological constant, incorporating theoretically motivated priors on the phenomenological Padé-w parameters used to model thawing dynamics. We find that thawing quintessence is consistently preferred over a cosmological constant when combining BAO data from DESI DR2 and CMB data from Planck+ACT with any of the major supernova compilations, including the recently updated DES-Dovekie sample. This preference is not sensitive to our choice of prior, but it is contingent on the inclusion of supernovae in the analysis. We comment on the consistency between various information criteria and Bayesian evidence ratios, finding that the Deviance Information Criterion (DIC) tracks the Bayesian evidence more reliably than either the Akaike Information Criterion (AIC) or the Bayesian Information Criterion (BIC). Finally, we use observational likelihoods to identify which thawing trajectories are compatible with the available data, independently of theoretical priors.
format Preprint
id arxiv_https___arxiv_org_abs_2512_20832
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle Thawing Quintessence: Priors, evidence, and likely trajectories
Shlivko, David
Cosmology and Nongalactic Astrophysics
General Relativity and Quantum Cosmology
We perform a Bayesian comparison between thawing quintessence and a cosmological constant, incorporating theoretically motivated priors on the phenomenological Padé-w parameters used to model thawing dynamics. We find that thawing quintessence is consistently preferred over a cosmological constant when combining BAO data from DESI DR2 and CMB data from Planck+ACT with any of the major supernova compilations, including the recently updated DES-Dovekie sample. This preference is not sensitive to our choice of prior, but it is contingent on the inclusion of supernovae in the analysis. We comment on the consistency between various information criteria and Bayesian evidence ratios, finding that the Deviance Information Criterion (DIC) tracks the Bayesian evidence more reliably than either the Akaike Information Criterion (AIC) or the Bayesian Information Criterion (BIC). Finally, we use observational likelihoods to identify which thawing trajectories are compatible with the available data, independently of theoretical priors.
title Thawing Quintessence: Priors, evidence, and likely trajectories
topic Cosmology and Nongalactic Astrophysics
General Relativity and Quantum Cosmology
url https://arxiv.org/abs/2512.20832