Poynting vector of a uniformly moving point charge

摘要

The covariant nature of electromagnetic fields is a well-known phenomenon. The Poynting Theorem predicts radiation to infinity of electromagnetic power for accelerating charges. The weaker Poynting fields of non-accelerating charges are not as well studied. Using linear coordinate transformations, the power density flux of a uniformly moving point charge is examined. In the frame of the moving charge, this quantity is necessarily zero. In the non-moving inertial system of the observer, the implications of the power balance on radiation, storage, and dissipation are discussed from the point of view that no outward radiation toward infinity occurs.