High Quality Content by WIKIPEDIA articles! A gravitational-wave detector is any device designed to measure gravitational waves, minute distortions of spacetime that are predicted by Einstein`s theory of general relativity. The existence of gravitational radiation is a prediction of general relativity. Gravitational waves are perturbations in the curvature of spacetime caused by accelerated masses. Since the 1960s gravitational-wave detectors have been built and constantly improved. The present-day generation of resonant mass antennas and laser interferometers has reached the necessary sensitivity to detect gravitational waves from sources in the Milky Way.