Dark Energy Survey: implications for cosmological expansion models from the final DES Baryon Acoustic Oscillation and Supernova data

Understand

The Dark Energy Survey (DES) recently released the final results of its two principal probes of the expansion history: Type Ia Supernovae (SNe) and Baryonic Acoustic Oscillations (BAO).

• We explore the cosmological implications of these data in combination with external Cosmic Microwave Background (CMB), Big Bang Nucleosynthesis (BBN), and age-of-the-Universe information.
• The BAO measurement, $\sim2\sigma$ away from Planck's $\Lambda$CDM predictions, pushes for low values of $\Omega_{\rm m}$ compared to Planck, in contrast to SN which prefers a higher value.
• We identify several tensions among datasets in the $\Lambda$CDM model that cannot be resolved by including either curvature or a constant dark energy equation of state.