GOODBYE Milky Way. Every galaxy is destined to slowly disintegrate as the dark matter that binds it together vanishes.
So predict Lawrence Krauss and Glenn Starkman at Case Western Reserve University in Cleveland, Ohio, who have studied a class of weakly interacting massive particles (WIMPs) that are prime candidates for dark matter.
These WIMPs are their own antiparticle, and most are thought to have annihilated each other in the very early universe. As the universe cooled and expanded, surviving WIMPs spread apart, making collisions rare. But in the cores of galaxies, dark matter is dense enough for many collisions to occur, say Krauss and Starkman. As a result, this dark matter will vanish and galaxies will slowly unravel (www.arxiv.org/astro-ph/0702333).
Luckily the process won't begin in earnest until the universe is 1010 times the age it is now.
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