Accidental symmetry
Encyclopedia
In physics
, in renormalization
theory, an accidental symmetry is a symmetry which is present in a renormalizable theory only because the terms which break it have too high a dimension to appear in the Lagrangian.
In the standard model, the lepton number
and the baryon number are accidental symmetries, while in lattice models, rotational invariance is accidental.
Physics
Physics is a natural science that involves the study of matter and its motion through spacetime, along with related concepts such as energy and force. More broadly, it is the general analysis of nature, conducted in order to understand how the universe behaves.Physics is one of the oldest academic...
, in renormalization
Renormalization
In quantum field theory, the statistical mechanics of fields, and the theory of self-similar geometric structures, renormalization is any of a collection of techniques used to treat infinities arising in calculated quantities....
theory, an accidental symmetry is a symmetry which is present in a renormalizable theory only because the terms which break it have too high a dimension to appear in the Lagrangian.
In the standard model, the lepton number
Lepton number
In particle physics, the lepton number is the number of leptons minus the number of antileptons.In equation form,so all leptons have assigned a value of +1, antileptons −1, and non-leptonic particles 0...
and the baryon number are accidental symmetries, while in lattice models, rotational invariance is accidental.