Maxwell's Macroscopic Electromagnetic Force

Abstract

The electromagnetic force, following from Maxwell's minimal macroscopic electromagnetic stress dyad, which reproduces analytically the measurements made by Coulomb[magnet-magnet force], Biot-Savart[current-magnet force], Ampere-Weber[current-current  force] and Faraday-Kelvin[polarization current-magnetization current force], is presented¹. This force leads to a space independent internal torque explaining experiments such as the Einstein de Haas effect [the rotation of a material in the presence of a uniform external magnetic field],² or the Barnett effect [the creation of the magnetic field by a rotation of a material]^3,4. The cause for the torque should not be, a priori, attributed to the asymmetry in the Cauchy's internal dyad⁵ - a conclusion which is unavoidable since the electromagnetic force is obtained from a symmetric dyad which leads to no internal torque.