If confirmed, the recently detected potential ripples from the Big Bang represent an imprint on the cosmic microwave background by gravitational waves. Those gravitational waves are produced through a quantum process, providing, for the first time (again, if confirmed), evidence that gravity is governed by quantum mechanics. This point cannot be overemphasized.
Given that the different members of the multiverse are not causally connected, the question that emerges is whether there is a way to verify whether such a multiverse truly exists. As it turns out, there are at least two possible paths that could (at least in principle) test the multiverse scenario.