Proper Time, Coordinate Systems, Lorentz Transformations

This Supplement explains some of the key concepts of the Special Theory of Relativity (STR). It shows how the predictions of STR differ from classical mechanics in the most fundamental way. It requires some basic mathematical knowledge.

Proper Time

The essence of the Special Theory of Relativity (STR) is that it connects three distinct quantities to each other: space, time, and proper time.