Comment on "How the potentials in different gauges yield the same retarded electric and magnetic fields," by J. A. Heras [Am. J. Phys. 75, 176 (2007)]
Abstract
Description
Heras purports to show without solving the requisite dynamic equations how the non-causal term generated by the scalar potential of the Coulomb, Kirchhoff, or velocity gauge is canceled by an equal and opposite term in the contribution to the electric field that is generated by the vector potential. Heras's procedure is criticized as being just an algebraic manipulation that has no explanatory content.
3 pages
3 pages