Quantum Field Theory
Related Category: Physics
study of the quantum mechanical interaction of
elementary particles and
fields. Quantum field theory applied to the understanding of electromagnetism is called
quantum electrodynamics (QED), and it has proved spectacularly successful in describing the interaction of light with matter. The calculations, however, are often complex. They are usually carried out with the aid of Feynman diagrams (named after American physicist Richard P.
Feynman), simple graphs that represent possible variations of interactions and provide an elegant shorthand for precise mathematical equations. Quantum field theory applied to the understanding of the
strong interactions between quarks and between
protons,
neutrons, and other
baryons and
mesons is called
quantum chromodynamics (QCD); QCD has a mathematical structure similar to that of QED.
See R. P. Feynman, QED (1985); F. J. Yndurain, The Theory of Quark and Gluon Interactions (1993).