EXAMPLE OF A POINCARE ANOMALY IN RELATIVISTIC QUANTUM-MECHANICS

The Poincare algebra of classical electrodynamics in one spatial dimen sion is studied using light-cone coordinates and ordinary Minkowski co ordinates. We show that it is possible to quantize the theory by a can onical quantization procedure in a Poincare-invariant manner on the li ght cone. We also show that this is not possible when using ordinary c oordinates. The physical reason for this anomaly is analyzed.