DESI DR2 Favors Metastable in Emergent Dark Energy with No Evidence for Dark Matter–Dark Energy Interactions

<title>Abstract</title> <p>The nature of dark energy remains one of the most fundamental open questions in modern cosmology. Among the proposed extensions of the standard cosmological model, interacting dark energy scenarios provide a physically motivated framework for exploring possible energy exchange within the dark sector and the dynamical evolution of cosmic acceleration. In this work, we present a comprehensive observational study of the Interacting Metastable Emergent Dark Energy (IMEDE) model using the Dark Energy Spectroscopic Instrument Data Release 2 (DESI DR2) baryon acoustic oscillation measurements, together with Planck PR4 CamSpec cosmic microwave background observations and three independent Type Ia supernova compilations: Pantheon$+$, DES-Dovekie, and Union3. We find that the IMEDE model provides a consistently better description of the DESI DR2 observations than the standard $\Lambda$CDM cosmology, with weak to moderate statistical significance based on the best-fit likelihood analysis and strong to decisive Bayesian evidence across the different dataset combinations. This statistical preference originates from a coherent reduction of the residuals across several independent BAO distance measurements rather than from any individual outlying data point.</p>