No one thinks that all of physics, or cosmology, is solved; the reigning problems in cosmology include contradictory conclusions about the age of the universe, and the nature of “dark matter” and “dark energy,” both terms being placeholders for unknown quantities needed to explain first, the amount of gravity in the universe, given observations of attraction among distant galaxies, and second, why the universe is expanding faster than expected.

This story has been floating around for a week or two, in various venues, to the point where it’s worth mentioning here. (A lot of radical ideas are put forth, many in pop venues, that gain no traction, and which therefore I don’t mention here.)
Phys.org, 15 Mar 2024: New research suggests that our universe has no dark matter









