In August of this year, researchers released the first results from the Dark Energy Survey, an international collaboration that's studying 26 million galaxies to understand how the universe has changed over the last 7 billion years. This led to the creation of the most detailed map of the visible universe.
This map was compared to what’s observed in the cosmic microwave background, which has been used to map what the very early universe looked like. The two maps are in perfect agreement following the prediction of the standard model of cosmology, a new confirmation that dark matter and dark energy continue to be the correct explanation for what we see in the cosmos. However, the survey hasn’t provided any new insight into the true nature of these mysterious dark matter and dark energy components.
The Kavli Foundation held a roundtable discussion with three scientists involved in the Dark Energy Survey who shared their frustration, hopes, and general sense of excitement about this puzzling area of cosmology.
“It does seem very strange that the results are good news, right? Forty years ago, nobody would’ve guessed that we apparently live in a universe in which most of the matter is stuff that doesn’t interact with us, and most of the energy is not even matter! It’s still super mind-blowing,” Professor Risa Wechsler, from Stanford University, said during the roundtable.
The results this summer were the culmination of over a decade's worth of work. The early findings are remarkably similar to what was discovered by the European Space Agency’s probe Planck in the early universe. The result is great but it doesn’t provide any groundbreaking views about the cosmos.
“It would’ve been very interesting if the results had significantly increased the tension with the cosmological standard model, which is the foundation for understanding why, beginning with the Big Bang, the universe is undergoing an accelerated expansion,” Professor George Efstathiou, who’s been involved in both Planck and the Dark Energy Survey, pointed out.
The Survey will next finish collecting information which will give the full analysis four times more data. It will definitely help refine the dark matter model and possibly locate where the “missing” dwarf galaxies around the Milky Way are. Exciting results will be produced, and maybe even some pipe dreams.
“Disproving the current model will revolutionize the way we think about the universe, so that’s the most exciting thing that I can imagine happening,” Professor Scott Dodelson, Head of the Physics Department at Carnegie Mellon University, added.
New surveys are already in the pipeline to expand this work and maybe someone will come along and make sense of dark matter and dark energy.