The D Potential - Unification of Electric and Magnetic Fields in the Steady State

This paper completes the steady-state description of the constructive reformulation of electromagnetism initiated in Paper I. Building on the experience principle and the propagation model, it clarifies the nature of the electric field as a real entity attached to each quantized charge, moving with it instantaneously yet possessing an intrinsic dynamism determined by the constant c. The force on a test charge is absolute and instantaneous, defined in the test charge's own experience, and involves only the perpendicular component of relative motion. For systems of multiple charges stationary relative to one another, the scalar field is shown to obey Gauss's law, leading to the steady-state curl equations Eₘ = c J and B = J. The vector potential D is introduced with = - D. Under three natural constraints—irrotationality, alignment with the propagation direction, and spherical symmetry—the Helmholtz decomposition E = - V + G is derived, with V = D c and G = D v_. From G the magnetic potential A and field B are obtained. Gauge invariance reduces to a constant shift along c, leaving all physical quantities invariant. This paper establishes the complete steady-state structure of electromagnetism from a single potential D, demonstrating that the conventional Maxwell equations are effective descriptions rather than fundamental laws. It sets the stage for Paper III, where time dependence and wave equations emerge from changing relative motion.