An experimental investigation of the influence of an electrostatic potential on electron mass as predicted by Weber's force law

Assis (J. Phys. Soc. Jpn. 62, 1418 (1993.) showed that Weber's force law between moving charges leads to the conclusion that the inertial mass of an electron depends on the charges that surround it. The experimental confirmation of this effect was claimed by Mikhailov (Annal. Fond. Louis de Broglie, 24, 161 (1999).) who detected frequency changes of a glow discharge lamp oscillator as a function of the voltage applied to the shield surrounding the oscillator. We carefully repeated the experiment employing an optical rather than the electrical coupling, used by Mikhailov, to measure the oscillator frequency as a function of shield voltage. Our results did not show any frequency changes associated with the change in shield voltage that could be interpreted as a change in the electron mass induced by the surrounding charges. As this effect is an inescapable consequence of Weber's force law, our experiment strongly indicates that this force law is not valid.