Concordance Cosmology?

Understand

We propose a new intuitive metric for evaluating the tension between two experiments, and apply it to several data sets.

• While our metric is non-optimal, if evidence of tension is detected, this evidence is robust and easy to interpret.
• Assuming a flat $\Lambda$CDM cosmological model, we find that there is a modest $2.2\sigma$ tension between the DES Year 1 results and the ${\it Planck}$ measurements of the Cosmic Microwave Background (CMB).
• This tension is driven by the difference between the amount of structure observed in the late-time Universe and that predicted from fitting the ${\it Planck}$ data, and appears to be unrelated to the tension between ${\it Planck}$ and local esitmates of the Hubble rate.