Electromagnetic Potentials Basis for Energy Density and Power Flux

TL;DR

This paper advocates for using electromagnetic potentials alone as a transparent basis for defining energy density and power flux in EM theory, offering clearer physical insights.

Contribution

It introduces a potential-based formulation for EM energy density and power flux, emphasizing its advantages over traditional field-based approaches.

Findings

Potential-based formulation enhances physical transparency.

Alternative EM definitions are compatible with Maxwell's equations.

Potential approach simplifies energy and momentum calculations.

Abstract

It is well understood that various alternatives are available within EM theory for the definitions of energy density, momentum transfer, EM stress-energy tensor, and so forth. Although the various options are all compatible with the basic equations of electrodynamics (e.g., Maxwell's equations, Lorentz force law, gauge invariance), nonetheless certain alternative formulations lend themselves to being seen as preferable to others with regard to the transparency of their application to physical problems of interest. Here we argue for the transparency of an option based on use of the EM potentials alone.