Physicists don’t know where most of the Universe’s apparent mass has gone, and attempts to find it have so far failed.
But a proposed particle born out of the Universe’s chaotic first moments may provide a candidate and a reasonable way to look for it.
Instead, what’s exciting is that this (comparatively simple) dark matter theory is compatible with the decades of tests that have constrained what dark matter might actually look like, as well as with the present-day understanding of the Universe.
The candidate particle leaves “a unique imprint on the large-scale structure of the Universe, that is, on the distribution of galaxies and galaxy clusters”, study author Tommi Tenkanen from Johns Hopkins University told Gizmodo in an email.
“This makes the hypothesis testable with astronomical observations in the near future.”
You can read our primer on the state of dark matter here, but basically, astronomical observations of distant galaxies and the Universe’s structure imply that there’s some source of gravity permeating the Universe that experiments can’t directly detect.