Maneesh Godbole wrote:I won't pretend I have understood an iota on what gravitational waves are or anything. All that happened to me was a jaw dropping experience. Einstein was sitting, probably smoking his favourite pipe, with his eyes on the nearby wall, tree, bicycle, sky, whatever, and in a moment of clarity it began to line up like clockwork and suddenly, he had it all figured out.
Well, I do think it's a bit less romantic than that. He had been working on his field equations for eight years after publishing his papers on special relativity. This is all pretty dry mathematics using tensors, and the prediction of gravitational waves is "just a result" from applying these field equations. I'm sure there are many things that general relativity predict that Einstein himself didn't predict.
As for gravitational waves, imagine putting a heavy ball on a trampoline. The ball is a mass, the trampoline is space-time and the bulge that the ball makes in the trampoline is the curvature of space-time. When the mass is at rest, there is curvature, but there are no waves. The two black holes merging is an event that you could picture as dropping a very heavy ball on the trampoline. Before it comes to rest, it may send ripples through the trampoline, much like ripples on a
pond when you throw a stone into it. Those ripples are similar to gravitational waves through space-time.