Is Dark Energy Dynamical in the DESI Era? A Critical Review

TL;DR

This paper critically examines whether recent DESI DR2 measurements support the idea of dynamical dark energy by analyzing various cosmological models and datasets, assessing deviations from the standard Lambda Cold Dark Matter model.

Contribution

It provides a comprehensive analysis of DESI DR2 data within extended dark energy models, evaluating the evidence for dynamical dark energy beyond LambdaCDM.

Findings

No strong evidence for dynamical dark energy from DESI DR2 data

Constraints on dark energy parameters are consistent with LambdaCDM

Extended models do not significantly improve fit over standard cosmology

Abstract

We investigate whether the recent DESI DR2 measurements provide or not evidences for dynamical dark energy by exploring the $\omega_0\omega_a$CDM model and its extensions with free $\sum m_{\nu}$ and $N_{\mathrm{eff}}$. Using a comprehensive MCMC analysis with a wide range of cosmological datasets including DESI~DR2 BAO and Ly$\alpha$ data, CMB compressed likelihoods, BBN, cosmic chronometers, and multiple Type~Ia supernova compilations, we assess the statistical preference for departures from $\Lambda$CDM.