Originally shared by Ethan Siegel
“We do not do science in a vacuum, completely ignoring all the other pieces of evidence that our scientific foundation builds upon. We use the information we have and know about the Universe to draw the best, most robust conclusions we have. It is not important that your data meet a certain arbitrary standard on its own, but rather that your data can demonstrate which conclusions are inescapable given our Universe as it actually is.
Our Universe contains matter, is at least close to spatially flat, and has supernovae that allow us to determine how it’s expanding. When we put that picture together, a dark energy-dominated Universe is inescapable. Just remember to look at the whole picture, or you might miss out on how amazing it truly is.”
20 years ago, the supernova data came back with an extraordinary surprise: it looked like the Universe wasn’t just expanding, but that the expansion rate was increasing as we head further into the future. While there were many dark energy skeptics to start, the increased flow of improved data from many lines of evidence that all kept pointing to the same conclusion has led to a cosmological consensus: dark energy dominates the Universe today. Last week, a story made waves, as Subir Sarkar and collaborators published their second paper (the first was in 2016) claiming that the evidence from supernovae is not good enough to support the existence of dark energy, and our cosmological foundation for it is extraordinarily shaky.
This is not true. This is demonstrably untrue. And the claim shows a deliberate unwillingness to pay attention to the rest of the field. Find out why dark energy must exist, despite recent reports to the contrary.