US astrophysicists Rainer Weiss, Barry Barish and Kip Thorne have been awarded the Nobel Prize for physics for their pioneering role in the detection of gravitational waves.
Predicted by Albert Einstein more than 100 years ago as part of his theory of general relativity, but only detected in 2015, gravitational waves are "ripples" in the fabric of space-time caused by violent processes, such as colliding black holes or the collapse of stellar cores.
Scientists say the detection of gravitational waves will open a new window on the universe.
