Displacementsström

Displacementsström is a theoretical concept in electromagnetism, specifically related to Maxwell's equations. It was introduced by James Clerk Maxwell to address an inconsistency he found in Ampère's law when applied to situations involving changing electric fields, such as within a charging capacitor. Ampère's law, in its original form, relates the magnetic field around a closed loop to the electric current passing through the loop. However, Maxwell realized that in the space between the plates of a capacitor, where there is no charge flow (and thus no conduction current), the electric field is changing as the capacitor charges.

Maxwell proposed that a changing electric field creates a magnetic field in a manner analogous to how an electric current does. He termed this phenomenon "displacementsström" (displacement current), and its magnitude is proportional to the rate of change of the electric flux through a given area. The inclusion of displacement current into Ampère's law, which becomes known as the Ampère-Maxwell law, resolved the inconsistency and led to the prediction of electromagnetic waves. This crucial addition unified electricity, magnetism, and optics, forming the foundation of classical electrodynamics and paving the way for understanding radio waves, light, and other forms of electromagnetic radiation. While displacement current is not a flow of charge, it has magnetic effects similar to conduction current.