In “Shedding light on the mystery of dark matter” (Nature, 3 September 2011), Ron Cowen reports “New findings spotlight conflicting results from search for elusive theoretical particles. The mass of dark matters turns out to be lower than suspected
Obviously, says theorist Neal Weiner of New York University in New York, somebody is wrong. But it’s unclear, he adds, whether some — or perhaps all — of the experiments are wrong, or if WIMPs are more complex than the relatively simple particles theorists have hypothesized. The dark-matter particles might interact differently with protons than with neutrons, or they may jump from lower internal energy states to higher ones, just as electrons jump from lower to higher energy levels in an atom. Such properties might explain the apparent discrepancies between experiments, but would contradict a popular theory of particle physics called supersymmetry, which posits that every known elementary particle has a heavier counterpart. More.
Could dark matter join the Higgs boson (the “God” particle) in last year’s theoretical particle zoo? Its existence is inferred in order to account for the strength of gravity; it wsn’t observed.
See also: But who was panicking about the missing “God particle” ? New Scientist comes to terms with the fact that the Higgs might not exist.