In “Dark matter no-show at sensitive underground lab” (New Scientist, 14 April 2011), Celeste Biever reports that the WIMPs (yes, yes,) wimped out:
It’s just like a wimp to be a no-show when summoned for interrogation. That seems to be the result of an experiment to detect the weakly interacting massive particles, or WIMPs, thought to make up elusive dark matter that is thought to make up much of the mass of the universe.
After 100 days of monitoring, a tub of cryogenically chilled liquid xenon deep in an Italian mountain has shown no trace of the particles it is designed to catch. The result doesn’t rule out the existence of WIMPs, but it does seem these particles are slipperier than previously hoped.
[ … ]
If no such signals appear in the coming decade, physicists are going to have to throw out much of what they think they know about dark matter and dream up new possibilities.
From UXL Encyclopedia of Science (2002):
The principal way dark matter can be detected is by observing its gravitational effect on nearby objects. Although dark matter does not shine, it still exerts a gravitational force on the matter around it. Astronomers believe that dark matter is a “cosmic glue” holding together rapidly spinning galaxies and controlling the rate at which the universe expands.