Albert Einstein, the Kinematics of Special Relativity

In classical kinematics the motion of an object is a function from a time-axis to the set of possible positions of the object in space. Time is absolute in the sense that the time-axis is an omnipresent clock. When it is 12 o’clock in the origin, it is 12 o’clock in the entire space. In 1905 Einstein published a paper that shook the world. In this chapter we discuss the birth of the theory of special relativity. In order to explain the phenomena it turned out to be necessary to give up the absolute character of time and not only that. We also describe the twin-paradox.