PHYSICS I Gravitational Waves Detected, Discovery Heralds New Era of Astronomy

摘要

On February 11th LIGO scientists announced the direct detection of gravitational waves, a discovery that will smash wide open a new door on the cosmos. Gravitational waves are ripples in the fabric of spacetime, predicted by Einstein's general theory of relativity (S&T: Dec. 2015, p. 26). They're created by accelerating masses, much as paddles sweeping through water spur vibrations in a pond. Previously, astronomers only had indirect evidence of their existence. But at 9:50:45 Universal Time on September 14, 2015, LIGO's two L-shaped labs — one near Hanford, Washington, and the other in Livingston, Louisiana ——caught the gravitational-wave signature of two colliding black holes.