Parallel Universe?

So I’ve entered yet another deep discussion.

Fantasy has long borrowed the idea of "another world" from myth, legend and religion. Often the alternative worlds theme in science fiction is framed by guessing that every historical event spawns a new universe for every possible outcome, resulting in a number of alternate histories. Sometimes the parallel universe bears no historical relationship to any other world.

While technically incorrect, and looked down upon by hard science-fiction fans and authors, the idea of another “dimension” has become identical with the term “parallel universe”. The usage is particularly common in movies, television and comic books and much less so in modern prose science fiction.

The idea of a multiverse is as fertile a subject for fantasy as it is for science fiction, allowing for epic settings and godlike protagonists. Multiverse is a hypothetical cosmos that contains our universe as well as heaps of other universes and space times.

What do you guys think? Do you think there is a parallel universe? I didn’t find another thread like this, sorry in advance if there already is.

~discuss

The Fantasy Of It All:

Most stories begin by simply transporting a character from the real world into the fantasy world where the bulk of the action takes place. Whatever gate is used is normally left behind and is left behind for the duration of the story, until the end, and then only if the protagonists will return [most of them do].

Multiple worlds, rather than a pair, increase the importance of the relationships. In The Lion, the Witch, and the Wardrobe, there are only our world and Narnia, but in other of C. S. Lewis's works, there are hints of other worlds, and in The Magician's Nephew, the Wood between the Worlds shows many possibilities, and the plot is governed by transportation between worlds, and the effort to right problems stemming from them.

 

Don't think there's been one like this recently...

Anyways, there are several parallel universe theories.
1) There is a multitude of universes, each slightly different from another, and the choices every living thing makes shunts their perception into a new universe, where that choice happened (the old show Sliders did this, in a way, with parallel universes being similar, but not the same (Nazis winning WW2, red means go, etc etc).

2) Theoretically, it might be possible to shift to another universe through a wormhole or a black hole, if you can survive the event horizon. This universe might not, however, be parallel, but instead follow it's own laws, and it may be that nothing from our universe can survive or even exist there (if the laws of physics are different, or in a pure energy universe).
a) there may also be millions of these universes.

I don't remember the rest off the top of my head. I'll update this if I can think of more.

Edit:
3) My personal favorite has to do with the dawn of the universe. Theoretically, this universe could have been spawned from a universe existing before us, when it collapsed into a "big crunch" (when the dark matter equivalent in that universe was weak enough that the universe collapsed under it's own gravity). This could, hypothetically, be just the latest in an uncountable eons-long chain of expanding, living, and collapsing universes. Ours, however, looks like it may end in a "big freeze", where the dark matter is strong enough to push our universe far enough apart that its gravity is not strong enough to collapse it, thus ending our nice, hypothetical chain. The sci-fi show Eureka made a reference to this theory, with the Artifact, a remnant from this previous universe.