symmetry

- group, ∞-group
- group object, group object in an (∞,1)-category
- abelian group, spectrum
- group action, ∞-action
- representation, ∞-representation
- progroup
- homogeneous space

A symmetry is (in most classical situations) invariance under a group action, or infinitesimally, invariance under a Lie algebra action.

In physics, see *local symmetry*, *global symmetry*, *spontaneous symmetry breaking*.

Revised on November 8, 2013 02:39:26
by Urs Schreiber
(92.68.97.89)