Attraction/repulsion between like charges and the spin of the classical mediating field

Abstract

The question as to whether an even or odd spin of the mediating field results in an attractive or repulsive force between like sources is examined within the framework of classical theory. It is shown that the assertion holds in a Lorentz-invariant theory constructed in analogy with electrodynamics provided that the current does not depend on any intrinsic direction of the source. Counterexamples are presented to show that the connection does not exist when the current does depend on the intrinsic direction.