Group action Orbit space Given a group acting on a space , the orbit space1 or quotient is the set of orbits partitioning . #m/def/group If is a topological space, is typically endowed with the quotient topology induced by the projection . Properties The Orbit space of a properly discontinuous group action is a covered by #state/tidy | #lang/en | #SemBr Footnotes German Bahnenraum. ↩