Time travel isn't possible. You can only "simulate" time travel in theory by accelerating an object or person to the speed of light. As you know, the faster you travel, the slower time passes for objects outside of your field of motion. It's impossible to travel backwards in time... essentially it isn't time travel at all, it's just Physics. masterchiefx2: You mean infinite energy right? The object travelling at the speed of light would approach infinite mass.