Parallel Dimensions

What are   parallel dimensions? Parallel dimensions are different universes which simultaneously exists with this universe but alternate and parallel. It is similar with the same concept of everything except slightly different. There can be an infinite amount of parallel dimensions, but the minimum amount is two. It's a set of nearly identical worlds. Therefore, if a person from this existing world travels to a parallel world, they would be able to recognize some basic features of it. The differences between alternative worlds can be strikingly obvious or so distinct that not a single person could notice it. For example, in a parallel dimension, the world could be 2 dimensional, or in another, a single grain of sand on the beach could've never been formed. But keep in mind that this is only a theory, and there is not enough evidence to prove that this is real.                                   ...