>>11264156Yes, sort of. First, as
>>11264345 pointed out, there're several types of multiverse, more than one of which may apply to reality.
I'll just talk here about the multiverse of many worlds quantum mechanics.
The thing with that is, at least to me, it appears to be the "default option". That is, taking a look at the math of quantum mechanics, it sure does at least look like you need to add extra questionable assumptions to get rid of the extra worlds.
So it sure seems as if, by default, the quantum multiverse is actually real, in that it seems to require the least amount of additional assumptions. There're still mysteries, though. But, for now, at least to me, single world models would seem to be even harder to believe than many worlds, because single world models seem to require extra things to be "just so" that we have less evidence for.
(Note that "worlds" are not exactly fundamental objects here. It would be more like... hrm, how should I put this? A... "blob", I guess, of quantum amplitude that is far away from any other nontrivial amounts, so effectively is an independent world that isn't going to be interfered with (in the sense of quantum interference) by external stuff.)
Now, if you mean the idea of traveling to alternate quantum branches, that's just sci-fi. At least, I myself don't know of anything remotely hinting that would be an option. (Not even sure what that would "look like"... you'd have to somehow, er... factor yourself out of the local "blob" of reality, and.. impose it on another elsewhere? no, even that isn't quite right.)
