Challenges to the cosmological constant model following results from the Dark Energy Survey

Abstract

In the past year, several pieces of evidence have pointed to a possible deviation from the standard cosmological model, the Λ cold dark matter model (where Λ is the cosmological constant). The recent work by the Dark Energy Survey collaboration reports a preference in the ballpark of 3σ in favour of dynamical dark energy against the standard cosmological model. For that, it used its final analyses of baryonic acoustic oscillations and type Ia supernovae, both of which are sensitive to the expansion history of the Universe, in combination with the cosmic microwave background from Planck. This adds to the growing debate about the nature of dark energy. Recent results from the Dark Energy Survey add to growing—but still tentative—evidence that dark energy may evolve with time rather than remaining constant. This Perspective presents these tensions and explores their potential implications for cosmology.