Archived Blog Post: October 20, 2003

Astronomers date Universe's 'cosmic jerk': "So after the big bang, matter was still relatively dense in the Universe and therefore gravity braked expansion. But as galaxies moved farther apart, dark energy began to exert a more significant influence. For a brief period, two forces balanced and 'the expansion of the Universe coasted along at a steady rate, like a car in cruise control,' says Riess."