When an object travels near the speed of light, they gain mass since the speed of light is the limit of how fast something can travel. If they gain mass when traveling at these speeds, and the law of conservation of matter says that matter can neither be distroyed nor created... So my question is: Where does this mass that is added come from? Since mass cannot be created. Do particles behave differently and have their own set of laws of behavior at such fast speeds? Because in nuclear reactions matter is distroyed because that is what the whole reaction is.:confused:

See: Conservation of mass - Wikipedia, the free encyclopedia