CANONICAL PROPER TIME FORMULATION OF RELATIVISTIC PARTICLE DYNAMICS

A canonical (contact) transformation is performed on the time variable (in extended phase space) to reexpress relativistic dynamics in terms of proper time, leaving the generalized coordinates and canonical mom entum as functions of this time variable. The form of the energy funct ional conjugate to this time variable is seen to be similar to that of a nonrelativistic dynamics at all values of particle momenta. The for mulation is explored for single- and multiparticle classical systems. The (form) invariance of the theory is determined by a group which res ults from a similarity action of the contact group on the Poincare gro up. One advantage of this approach is that it overcomes the no-interac tion difficulties introduced by standard methods.