New Data Support Einstein on Accelerating Universe
Researchers with the BOSS project have measured the distance to faraway galaxies more precisely than ever before, mapping the universe as it existed roughly 6 billion years ago, when it was only 63 percent of its current size. The findings suggest that the mysterious â€œdark energyâ€ causing the universe to expand at an accelerating rate was foreseen by Einstein, the researchers reported at the American Physical Society meeting.
To keep the universe in a static state, Einstein added a term called the â€œcosmological constantâ€ to the equations for his theory of general relativity; when the universe was later found to be expanding, he called the constant his â€œbiggest blunder.â€ But in recent years, the cosmological constant, which describes a repulsive force occupying all of space, has been invoked to explain the discovery, first reported in 1998, that the universe is expanding faster and faster. Evidence for accelerated expansion could be explained either by the negative pressure exerted by the cosmological constant (or some other form of dark energy) or by some flaw in general relativity. The BOSS results support the dark energy picture.