Physicists detect gravitational waves from violent black-hole merger

Scientists announced Thursday that, after decades of effort, they have succeeded in detecting gravitational waves from the violent merging of two black holes in deep space. The detection was hailed as a triumph for a controversial, exquisitely crafted, billion-dollar physics experiment and as confirmation of a key prediction of Albert Einstein's General Theory of Relativity.

It will also inaugurate a new era of astronomy in which gravitational waves are tools for studying the most mysterious and exotic objects in the universe, scientists declared at a euphoric news briefing at the National Press Club in Washington...