Category: shape of the universe

Ask Ethan: Could The Shape Of Our Universe Be Closed Instead Of Flat?

“I thought that the curvature parameter had been essentially settled upon by WMAP, Planck, and other astronomical measurements. I am curious what you think about the validity of this recent paper. Is the Universe actually closed with a detectable positive curvature as the authors of the Nature Astronomy paper suggest? If the Universe is spherical, then how big would the sphere be according their measurements?”

About 2 weeks ago, a team of scientists took a detailed look at the latest Planck results, the most sophisticated, highest-precision map of the Cosmic Microwave Background ever obtained. But rather than look simply at the temperature fluctuations, they looked at a different signal: the effect of gravitational lensing. And instead of finding the flat Universe that other types of analysis yield, they favored a closed, positively-curved Universe at about the 4.4% level, creating a greater-than-3-sigma tension with the rest of the Planck data.

Does that mean the Universe could be closed instead of flat? Not if you look at the consequences of this dastardly interpretation. Get the real science on Ask Ethan today.