quantum electrodynamics
Sign in to saveAbelian gauge theory describing quantum interactions of the electromagnetic field with matter
AI overview
Quantum electrodynamics is a theory that explains how light and charged particles interact with each other using the rules of quantum mechanics. It matters because it provides an exceptionally accurate framework for understanding electromagnetic phenomena at the smallest scales, from how atoms emit light to the behavior of electrons and photons.
AI-generated from the Wikipedia summary — may contain errors.
Article
In particle physics, quantum electrodynamics (QED) is the relativistic quantum field theory of electrodynamics. In essence, it describes how light and matter interact and is the first theory where full agreement between quantum mechanics and special relativity is achieved. QED mathematically describes all phenomena involving electrically charged particles interacting by means of exchange of photons and represents the quantum counterpart of classical electromagnetism giving a complete account of matter and light interaction.
In technical terms, QED can be described as a perturbation theory of the electromagnetic quantum vacuum. Richard Feynman called it "the jewel of physics" for its extremely accurate predictions of quantities like the anomalous magnetic moment of the electron and the Lamb shift of the energy levels of hydrogen. It is the most precise and stringently tested theory in physics.