Examining the evidence for dynamical dark energy

Abstract

We apply a new non-parametric Bayesian method for reconstructing the evolution history of the equation-of-state $w$ of dark energy, based on applying a correlated prior for $w(z)$, to a collection of cosmological data. We combine the latest supernova (SNLS 3-year or Union2.1), cosmic microwave background, redshift space distortion and the baryonic acoustic oscillation measurements (including BOSS, WiggleZ and 6dF) and find that the cosmological constant appears consistent with current data, but that a dynamical dark energy model which evolves from $w<-1$ at $z\sim 0.25$ to $w>-1$ at higher redshift is mildly favored. Estimates of the Bayesian evidences show little preference between the cosmological constant model and the dynamical model for a range of correlated prior choices. Looking towards future data, we find that the best fit models for current data could be well distinguished from the $\Lambda$CDM model by observations such as Planck and Euclid-like surveys.

5 pages, 2 figures, accepted to PRL

References in corpus (5)

• Supernova Constraints and Systematic Uncertainties from the First 3 Years of the Supernova Legacy Survey
• Reconstructing Dark Energy
• Nonparametric Dark Energy Reconstruction from Supernova Data
• On model selection forecasting, Dark Energy and modified gravity
• Reduction of Cosmological Data for the Detection of Time-varying Dark Energy Density

Cited by in corpus (6)

• The Parameterized Post-Friedmann Framework for Theories of Modified Gravity: Concepts, Formalism and Examples
• Uncertainty on w from large-scale structure
• A global fit study on the new agegraphic dark energy model
• A new extended quintessence
• A Brief History of Curvature
• Considering Late-Time Acceleration in some Cosmological Models