The relation between classical and quantum electrodynamics

TL;DR

This paper argues that quantum electrodynamics (QED) cannot be simply derived from classical electrodynamics but should be viewed as an extension that addresses phenomena beyond classical theory's scope.

Contribution

It clarifies the conceptual relationship between classical and quantum electrodynamics, emphasizing that QED is an extension rather than a reduction of classical theory.

Findings

QED cannot be recovered from classical electrodynamics through limiting procedures.

QED extends classical electrodynamics to describe phenomena it cannot address.

Classical and quantum electrodynamics are related but fundamentally distinct frameworks.

Abstract

Quantum electrodynamics presents intrinsic limitations in the description of physical processes that make it impossible to recover from it the type of description we have in classical electrodynamics. Hence one cannot consider classical electrodynamics as reducing to quantum electrodynamics and being recovered from it by some sort of limiting procedure. Quantum electrodynamics has to be seen not as a more fundamental theory, but as an upgrade of classical electrodynamics, which permits an extension of classical theory to the description of phenomena that, while being related to the conceptual framework of the classical theory, cannot be addressed from the classical theory.