" In a galaxy far, far away, at a time when the Earth hosted nothing bigger than a simple bacterium, two monster black holes, locked in a death-spiral, swung around each other one last time. As they kissed and coalesced, three whole solar masses vanished, reappearing instantly as a tsunami of a warped space-time, which raced outwards at the speed of light. For an instant its power was fifty times greater than that of all the stars in the Universe put together. "

― Marcus Chown , The Ascent of Gravity: The Quest to Understand the Force that Explains Everything