Chapter

Compendium of Quantum Physics

pp 248-255

Gauge Symmetry

  • Holger LyreAffiliated withPhilosophy Department, University of Bielefeld

* Final gross prices may vary according to local VAT.

Get Access

Gauge symmetries characterize a class of physical theories, so-called gauge theories or gauge field theories, based on the requirement of the invariance under a group of transformations, so-called gauge transformations, which occur in a theory's framework if the theory comprises more variables than there are physically independent degrees of freedom. Gauge ► symmetry was firstly acknowledged in Maxwell's electrodynamics, where the vector potential shows a freedom of transformation in the sense that it is not uniquely determined by the Maxwell field equations, but only up to adding the derivative of a scalar function. Since all three fundamental quantum field theoretic interactions as well as gravity can be reconstructed within a gauge theoretic framework, gauge field theories represent the backbone of modern physics today, that is, the physics of the Standard Model and beyond. ► Quantum field theory; particle physics.