UFO's and extra-terrestrial life

[NedLynch]

Other dimensions are certainly a critical part in traveling to further reaches of the universe.
The thing is we are 3-dimensional beings with time as the 4th dimension sort of tacked on and taken for an unchangeable constant. Introducing other dimensions is something that we will probably not be able to comprehend.

For example, take a 2-dimensional critter, maybe and ant, and put it on a ball.
It will run and run and never ever be able to understand that it is running on a ball, a 3-dimensional object.

Something that puzzles me is also, if the universe is finite one should be able theoretically to reach it's end and to look at it from the outside. But what is on the outside, another finite universe, infinite space, nothing? How, as a 3-dimensional, spacewise, being can you wrap your head around the concept of a finite or infinite universe?