The DES is primarily asking if dark energy can be a cosmological constant. However, I am a little uncertain about what exactly it means by "constraining cosmology/dark energy?
Interesting problem I came across, yet I'm having some trouble with it:
Here are a few of the next generation of experiments currently being planned for constraining cosmological models. Not all of these are groundbased:
DES:https://www.darkenergysurvey.org/"...