From today’s* Guardian*:
Physicists have announced the discovery of gravitational waves, ripples in spacetime first anticipated by Albert Einstein a century ago.
“We have detected gravitational waves. We did it,” said David Reitze, executive director of the Laser Interferometer Gravitational-Wave Observatory (Ligo), at a press conference in Washington.
The announcement is the climax of a century of speculation, 50 years of trial and error, and 25 years perfecting a set of instruments so sensitive they could identify a distortion in spacetime a thousandth the diameter of one atomic nucleus across a 4km strip of laser beam and mirror.
The phenomenon was detected by the collision of two black holes. Using the world’s most sophisticated detector, the scientists listened for 20 thousandths of a second as the two giant black holes, one 35 times the mass of the sun, the other slightly smaller, circled around each other.