w

excerpt from Science magazine, 2003, June 20, p. 1896

Earlier this year, physicist Robert Caldwell of Dartmouth College in Hanover, New Hampshire, and his colleagues investigated what happens if w is less than -1, for example, if it's -1.1 or -1.2 or -2. Physicists had shied away from such values, because they make theoretical equations start spewing out ugly infinities and other logical inconsistencies. But Caldwell's group didn't flinch. "Interesting things happen as dark energy becomes more and more repulsive," says Caldwell.

"Interesting" is putting it mildly: The universe dies a horrible death. The ever-strengthening dark energy makes the fabric of the universe expand ever faster and things fall apart. In a few billion years, galaxy clusters disintegrate. The galaxies' mutual pull is overwhelmed by the dark energy, and they spin away from each other in ever-widening gyres. Several hundred million years later, galaxies themselves, including our own Milky Way, fling themselves to pieces. Solar systems and planets spin into fragments. Even atoms lose control of their electrons, and then atomic nuclei get torn apart and protons and neutrons shatter under the enormous expanding pressure. "Space becomes unstable," says Riess. The universe ends in a "big rip" a cataclysm where all matter gets shredded by the ever-stretching fabric of spacetime.