Structures, i.e. symmetries over time, appear in various systems:
- gliders in cellular automata, like Game of Life or Rule 110,
- unmatched string's parts in rewrite systems – unchanged in multiple rewriting steps (or matched, but rendered unchanged in some part, etc.),
- basically, each dynamic system (in the sense of chaos theory, and also wider – each system that changes its configuration over time) can have more or less symmetry.
Are there some works on the topic, i.e. on abstract treatment of symmetries in systems?