The electromagnetic linear and angular momenta are defined as an integral of the appropriate density over a forward lightcone. It will be shown how to relate the electromagnetic momenta, for a system of charged point particles, as an integral over finite segments of each world line. Other treatments of this problem, where the momenta is defined as the integral over a spacelike hyperplane, require the integral over infinite segments of the world lines. In general, these integrals diverge for point particles. However, the integrals over the forward lightcones are finite. Several examples are worked.
ASJC Scopus subject areas
- Statistical and Nonlinear Physics
- Mathematical Physics