“Gravitational waves are ripples in spacetime. When objects move, the curvature of spacetime changes and these changes move outwards (like ripples on a pond) as gravitational waves. A gravitational wave is a stretch and squash of space and so can be found by measuring the change in length between two objects.”
So the idea of gravitational waves was first postulated by Einstein when he developed the theory of general relativity, which in short allows for space-time to be warped. This is how Einstein’s gravity works, the more massive an object is, the more it bends space-time. A good analogy is a bed with a bowling ball on it, the bowling ball causes a large depression on the bed. A marble on the other hand will only cause a tiny depression on the bed. This is in short how gravity works according to Einstein.
Gravitational waves explained: Why the detection of ripples in spacetime is so important?
Scientists will now be able to track objects that don’t emit visible light, such as black holes and neutron stars, and other objects we might not even be aware of.
Being able to detect and analyse the information carried on them would open up a new area of study of some of the most important events in the history of the universe, such as the Big Bang, and help us find out more about how the universe was created.
According to Newton gravitational waves can’t exists since gravity propagates out at an infinite speed, so this does prove Newtonian Gravity
But what happens when you drop the bowling ball onto the bed? It causes a wave to move through the bed (although it is a very, very tiny wave, not even close to as big as a water wave or something that isn’t as solid). Einstein predicted that the same would happen if a mass were to suddenly appear in space or if the mass/shape of a mass were to change, however like the bowling ball on the bed the wave would be minuscule and very hard to detect, so he believe it would be impossible to prove.