The uncertainty of science: Having failed to detect WIMPs, their primary dark matter suspect, physicists are now looking at new and different candidates that might explain dark matter, and the new leading candidate is something called SIMPs.
The intensive, worldwide search for dark matter, the missing mass in the universe, has so far failed to find an abundance of dark, massive stars or scads of strange new weakly interacting particles (WIMPs), but a new candidate is slowly gaining followers and observational support.
Called SIMPs – strongly interacting massive particles – they were proposed three years ago by UC Berkeley theoretical physicist Hitoshi Murayama, a professor of physics and director of the Kavli Institute for the Physics and Mathematics of the Universe (Kavli IPMU) in Japan, and former UC Berkeley postdoc Yonit Hochberg, now at Hebrew University in Israel.
Murayama says that recent observations of a nearby galactic pile-up could be evidence for the existence of SIMPs, and he anticipates that future particle physics experiments will discover one of them.
We shall see. The mystery remains, that we do not understand why most galaxies do not fly apart because their outer stars simply move too fast. Since all searches for ordinary matter have come up well short, dark matter remains the simplest explanation, though it still reminds me the theories of ether that once dominated physics, and never existed.