I recently watched Superman-Man of Steel. In the movie used some sort of gravity weapon to divert missiles. It also showed one thing they called 'The World Engine' to modify earths gravity. When considering Gravity just another field like Electric field(to which it is very similar to). We do easily can change Electric field of place easily. So, is that sort of gravoty weapon(modifier) possible in future or in present(might already be in use and not in my knowledge), Or is it just a fiction and remain fiction?