A Gravitational Wave is an invisible ripple in space that travels at the speed of light, and squeezes and stretches anything in their path as they pass by. The Gravitational Wave is a concept predicted by Einstein’s theory of general relativity.
Reference Definition by Wikipedia: In physics, Gravitational Waves are ripples in the curvature of space-time which propagate as waves, travelling outward from the source. Predicted in 1916 by Albert Einstein on the basis of his theory of general relativity, gravitational waves transport energy as gravitational radiation. The existence of gravitational waves is a possible consequence of the Lorentz invariance of general relativity since it brings the concept of a limiting speed of propagation of the physical interactions with it. By contrast, gravitational waves cannot exist in the Newtonian theory of gravitation, which postulates that physical interactions propagate at infinite speed.
