If you are the only object in the universe, what speed are you going? Well there would be no such thing as speed because your speed is only relative to other objects. So if there is no such thing as speed, how is there a speed limit? Let me give an example. If you take off from earth in a really fast rocket to visit another planet, when you come back, you will have aged less than everyone on earth because time slowed down for you. But how did you go faster than the people of earth when its all relative? You simple got father away from the people of earth, then you got closer to the people of earth. Who is to say if your rocket moved or the earth moved. There is no difference.