Science

The cosmological principle holds that the universe is homogeneous (the same everywhere) and isotropic (the same in all directions). A quick glance at the night sky shows this cannot be true at all levels, because the void of space is dotted with dense clumps of stars. Nevertheless, cosmologists assume the universe is essentially uniform and featureless when averaged over sufficiently long length scales

Previous studies typically asked the question: Given a galaxy at any one point, how likely is it to find another galaxy at a particular distance, regardless of direction? “In general, people measure the probability function of the distance,” Sylos Labini says. “Here we are measuring how it varies with both distance and angle.”

To do that, the researchers sliced the DESI map into 2D slices, examined pairs of galaxies separated by a given distance, and looked for patterns in how those pairs were oriented. In a homogenous universe, those directions should be randomly and evenly distributed. Instead, the researchers found significant correlations in the directions, suggesting the distribution of galaxies remains stringy over much larger distances than lambda-CDM simulations predict.

However, David Spergel, a cosmologist at the Flatiron Institute, is skeptical of the new claim. If structures extend across billions of light-years, he says, their gravity should dramatically distort the lingering afterglow of the Big Bang, the cosmic microwave background (CMB). “The result very much appears to be in contradiction with much more sensitive measurements from the microwave background.” Sarkar counters that if Spergel and others can use observations of the CMB to rule out the new result, “then they should do it.”

Now that's some good science smack talk.

e: also side note, the Flatiron Institute is privately funded from the fortune of hedge fund manager Jim Simons (known for unprecedented profits). Both Jim and David appear in some certain files.