PlanetPhysics/Groupoid Action
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Let Failed to parse (unknown function "\grp"): {\displaystyle \grp} be a groupoid and a topological space. A groupoid action , or Failed to parse (unknown function "\grp"): {\displaystyle \grp} -action, on is given by two maps: the anchor map and a map with the latter being defined on pairs such that , written as . The two maps are subject to the following conditions:
- and
- whenever the operations are defined.
{\mathbf Note:} The groupoid action generalizes the concept of group action in a non-trivial way