Scientists have finally figured out some tests to see if we really do live in a "multiverse". As I understand it, a lot of conflict between relativity and quantum mechanics, particularly with regard to gravity, can be explained if our universe is just one of many "bubble" universes. And that's about as far as I can get, since the physicists who's books I've read sort of sputter out at that point because they can't use the right sort of math in a popular science book. Anyway, testing is good!