Definition and Origin Gravitational waves are invisible ripples in the fabric of space-time caused by some of the most violent and energetic processes in the universe. Predicted by Albert Einstein in 1916 as part of his General Theory of Relativity, these waves propagate outward from their source at the speed of light, stretching and squeezing space as they pass. While accelerating masses generate these waves, they are typically too weak to detect unless produced by cataclysmic events, such as the collision of black holes or neutron stars.

Detection Technology Detecting these waves requires measuring changes in distance smaller than a fraction of a proton's width. Observatories like LIGO (Laser Interferometer Gravitational-wave Observatory), Virgo, and KAGRA use massive laser interferometers. In LIGO, laser ...