Learn more about:

Dark Matter


Related Topics:


Hot and Cold Dark Matter

Carlos Frenk:
Closing in on the Missing Matter


Short for Weakly Interacting Massive Particles, the ghostly WIMPs are predicted by theory but have so far eluded detection. With odd names like photino and masses of perhaps 10 to 100 times that of the proton, WIMPs could account for lots of dark matter if, as some theories predict, they are common in the universe. Cosmologists like cold-dark-matter WIMPs because they would be relatively heavy and thus move much slower than the speed of light. If so, they could have been the gravitational “seeds” around which regular matter congregated to form galaxies yet, because they don't interact with radiation, not affect the observed smoothness of the cosmic background radiation.


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