The idea of us having a parallel Universe (one), comes from the theory of The Big Bang, which i'm sure all of you know. Nothing, Big Bang, Universe, basically. Anyway, one of the things about the theory of the Big Bang that caused many scientists to not accept it is that theoretically, when the Big Bang occured and created our Universe it also created an identical Universe with one exception. Thw two Universes differ in that one is a Matter Universe and the other is an Anti-matter Universe. Matter and anti-matter are basically the same thing except that, for example a proton has a (+) charge while an anti-proton has a (-) charge. So, the only difference between the two Universes is that the charges of all particles are opposite eachother. The problem with anti-matter/matter is, as soon as they come in contact they completely enielate eachother. This stems from Einstein's E=mC^2 equation. So, we have just recently discovered how to create anti-matter, the only problem is, once we create it, as soon as it touches anything it is destroyed. This ofourse creates a massive amount of energy, yet we unfortunatly cannot harness this energy. So, this brings me to my final point, are we in the matter Universe or the anti-matter Universe? We could be anti-matter creating matter, or visa versa. Just a thought.