An interesting and an intriguing question.
We all have been at some time in our age, fantasized by Superman and his superhuman capabilities. Superman can travel at the speed of light as shown in some movies or even faster. Can it be possible in reality?
In early 1900, Albert Einstein changed the way of physics as it was at that time. The theory of relativity states that-
The speed of light (186000 miles per sec) as suggested by Isaac Newton does not depend upon the source or light or the motion of the observer. It means that a moving beam has nothing to do with how another thing is moving. Thus, if superman were to chase a travelling beam of light with a certain speed, the beam of light would continue to move away from him with the same speed.
The famous equation, E = mc² provides a relation between mass and energy. Both are directly proportional to each other, it means as the energy of an object increases the mass of the object also increases. If an object moves really quickly, the mass of the object is likely to increase. Thus, if an object moves with 186000 miles per sec, the mass of the object becomes infinite and infinite energy is needed to move it. This is the reason that we can’t move faster than light.