B     The Three Fundamental Consequences

Adhering to the principle of relativity and Maxwell’s equations has three fundamental consequences: The simultaneousness of two events loses their absolute character, different observers of an activity will no longer measure the same duration, and the distance between two points (or the length of an object) loses its absoluteness. We discuss the experimental confirmation of these basic phenomena from two perspectives. Finally we derive the amount the two clocks appear desynchronized to a moving observer, given that they are synchronized in their own inertial frame.