Simultaneity

The simultaneity of two pointlike events (that occur in a small space in a short period of time) needs to be reconsidered. You cannot define simultaneity irrespective of a reference frame. Let us assume that an observer is looking at two events (A and B) simultaneously in a reference frame. Another observer observing the same events in a moving reference frame (from an aircraft, e.g.) finds that one of them (let's say, B, towards which he is moving), happens sooner. The following program demonstrates this phenomenon. A high speed aircraft passes over an observation tower. At this time, a light signal is emitted and two towers will detect it, which are the same distance from the observer tower. Upon detecting the signal, we hear a sound and see a white dot light up.




Previous next experiment.