According to the theory of relativity you cannot go faster than light, and I'm inclined to believe einstein. This doesn't mean travelling to parallel dimensions isn't possible. If you look into the field of quantum physics that is explored in that book I mentioned above things like that may actually be possible.
Originally posted by pac91303
Why can't Stargate be true? It's just travelling through a worm hole at faster then light speed. And both of those theories are close to being proven as true. As for 'Sliding' to another dimension. Some well respected scientists think it's possible at the center of a black hole.