Researchers have developed a new technology that aims to make the Advanced Laser Interferometer Gravitational-Wave Observatory (LIGO) even more sensitive to gravitational waves.
Scientists at Advanced LIGO announced the first-ever observation of gravitational waves earlier this year – a century after Albert Einstein predicted their existence in his general theory of relativity.
LIGO, the Laser Interferometer Gravitational-Wave Observatory, has been twenty-five years and more than half a billion dollars in the making. It involves 900 scientists and engineers, including many whose entire careers have been spent designing, building, and preparing to analyze data streaming in to LIGO. Their goal: To confirm, once and for all, Einstein’s century-old idea that gravity travels across space-time in the form of gravitational waves.
A visualization of two black holes merging based on general relativity’s predictions.
Gravitational waves are something else entirely: they are gravity’s messengers, ripples in the fabric of space that reverberate out from the source of a gravitational disturbance. You can’t see them, but you can feel them, like you feel the wake of a passing speedboat on the water. The bigger the boat, the bigger the waves, and so it goes with gravitational waves. Really hefty objects—supermassive black holes containing as much matter as hundreds of millions of suns—make big billows in space-time. Littler things—a moon, a mouse—leave barely a quiver.
if an object is just sitting still, its gravitational field is static and unchanging. But if the object’s motion is changing, or if its mass is being dramatically rearranged, like in an explosion or implosion, the gravitational field changes, too, and that change produces gravitational waves. A black hole sitting peacefully in isolation is silent and invisible to gravitational wave detectors, but a black hole on a collision-course spiral around another black hole should be positively shrieking. Which is exactly what the LIGO team heard.