The Dark Energy Survey have published their latest findings based on their most abundant data set yet of 100 million galaxies across a large section of the sky. They have used an advanced analysis based on a model consisting of correlations between pairs of galaxies to determine the values of various cosmological parameters to a rather impressive degree of accuracy. This can be compared with the parameters derived from other observations, in particular data from the analysis of the cosmic microwave background by the Planck experiment. Any serious discrepancies between results derived from galaxy data and CMB data could lead to some new discoveries in cosmology.

<https://www.darkenergysurvey.org/wp-content/uploads/2021/05/desy3_3x2_results.pdf>

In particular, they have measured the clustering of galaxies to be slightly less than expected by the Planck data, though the difference is certainly not large enough to be serious (in fact, the agreement is better than it was for their previous analysis with less data). They have also measured the matter density of the observable universe to be in agreement with the Planck data, though the precision they can achieve for this parameter is far lower than is possible with Planck. They also measured an important property of dark energy without the assumption that its energy density remains constant in time, and interestingly their data combined with the Planck data prefers a so-called "phantom energy" scenario, where the energy density of dark energy actually increases as the universe expands, leading to an eventual Big Rip and the destruction of spacetime.