The length of an object or the time that an object experiences is relative to its speed (in relation to the objects around it). This phenomenon required that reference frames be noted. When an object is traveling close to the speed of light, time will pass more slowly on that object relative to objects that are (relatively) stationary. To the traveling object, however, the stationary objects appear to be traveling near the speed of light. These objects also experience the passage of time more slowly than the traveling object. A similar phenomenon occurs with the length of the object, wherein the object becomes shorter relative to the objects which it is passing by. This contraction factor is called gamma.
