Abstract

Maxwell's equations maybe derived on an information-theoretic basis. Consider a gedanken experiment whereby the space–time coordinate. An efficient (optimum) estimate obeys a condition of minimum Fisher information, or of minimum precision, according to the second law of thermodynamics. The Fisher information is a simple functional of the probability law governing the space–time coordinates of the photons in the field. This probability law is taken to be the local intensity in the optical sense, i.e., the square of the four-vector potential. The principle of minimum Fisher information states that the correct probability law results from minimizing the information subject to a constraint in the mean kinetic energy of the particles of the field. In the electromagnetic field, the closest concept to kinetic energy is the free energy, i.e., the energy available for kinetic energy were a particle of finite mass to enter the field. When the Fisher information is minimized subject to a constraint on mean free energy, Maxwell's equations result.

© 1990 Optical Society of America