ABSTRACT
A true example of a difference in temporal intervals may be given. If a spaceship travels by the earth with a light clock and the spaceship is traveling at 99.5 per cent of the speed of light, nearly 186,000 mps, then a second hand on a clock in the spaceship would move only six seconds during the time that the second hand on our clock would move sixty seconds. Time goes ten times slower on the spaceship, relative to the reference frame of the earth. Every physical process on the spaceship goes slower, relative to the reference frame of the earth. Thus, people on the rocketship would age slower and live longer than the people on the earth, relative to the reference frame of the earth. Conversely, the people on the rocketship would observe people on the earth aging more slowly and living longer.
