NONUNIQUENESS OF THE PHYSICAL ACCELERATION FOR THE LORENTZ-DIRAC EQUATION

The Lorentz-Dirac equation is analyzed for the case of a charged particle injected into a step-function electric field of finite extent. It is shown that for small exit velocities, the relation between entrance and exit velocities is ''inverted'' in the sense that the larger the entrance velocity, the smaller the exit velocity. As a consequence, some entrance velocities can yield at least two distinct exit velocities. Numerical evidence bearing on the possibility of experimentally detecting this dichotomy is presented.