Have you ever been in a situation where you chose one thing over another? Yeah, there's a universe out there where the other option was the one 'you' chose.
I would pick this one as it kind of goes with the butterfly effect, although that is just to do with time.... -_-
I'm not sure if there has been any real evidence to prove this concept, but it is fun as heck to think about.
I just like the idea of a universe were North Korea wasn't a crazy country. Even in with an infinite amount universes, Kim Jong Un would still be crazy.
The multiverse is still the universe. Science just likes to play with words.
Universe = everything that exists.
The multiverse is not a theory, it's speculation. In order to arrive at a theory, an idea must be constructed into a hypothesis which yields results that are testable, repeatable, observable, and verifiable before it becomes a theory. This is what is called the scientific method. The scientific method is incapable of even approaching the idea of a multiverse. Scientists who chide people for believing in things without scientific evidence seem all to willing to engage in a serious discussion about something that is scientifically unworkable like the multiverse. It also turns Ockham's Razor on its head. O.R. states that causes should not be multiplied beyond what is necessary, in other words the simplest solution is usually the correct one. Scientists seem to favor abolishing the idea of ONE unobservable God and replacing it with an INFINITE number of unobservable universes. It seems gratuitous to speculate an infinite number of possibilities when one God will do. Putting any intellectual stock in the notion of a multiverse is the epitome of "blind faith"-or more accurately blind hope. The idea though does make for some entertaining sci-fi movie plots though.