Relativistic Collisions

Abstract

In Einstein’s theory, the inertial coordinate systems that observers use to label events in Minkowski space are related by Lorentz transformations. This gives a consistent, if unfamiliar, framework within which to understand relative motion. It is one in which the conspicious incompatibility between Maxwell’s equations and the principle of relativity is resolved because the velocity of photons is always the same, whatever the motion of the source or the observer. But there is a price; Newton’s laws are invariant under Galiliean transformations, but not under Lorentz transformations. In fact, Galilean invariance is a corollary of Newton’s laws. So if Einstein’s picture of space-time is the correct one, then we must revise the basic principles of dynamics.