Speed of Light Barrier

Umm I recently read a book about this, and it said that the universe might be much bigger than we know it as, because gravity moves at the speed of light. How he proved gravity moved the speed of light was a little foggy to me, and I don't want to try to explain it, because I could be completly wrong. It also said space can be expanding faster than the speed of light because of relativity. If two galaxies are expanding at x a galaxie twice the distance away from one of thoose galaxies will be expanding at 2x. This seemed pretty obvious and simple, and a galaxie that space is expanding faster than the speed of light, the light or gravity would never reach us.

The book's name is fabric of the cosmos by Brian Greene. There was much of this book that I didn't understand though, but the major concepts I think I got.

Hmm you techniqually couldn't move, but you to say if you were in a spaceship to the outside you would move at lightspeed. Time is completly stopped at lightspeed so to move faster should reverse time. Fortunalty there is no way to get to lightspeed. If you were able to send matter at lightspeed it would take an infinte amount of energy, and if you had an infinte amount of energy this would mean infinte gravity, and the universe quite frankly would come crashing down around you instantly.