Properly Discontinuous Action
In topology and related branches of mathematics, an action of a group G on a topological space X is called proper if the map from G×X to X×X taking (g,x) to (gx,x) is proper, and is called properly discontinuous if in addition G is discrete. There are several other similar but inequivalent properties of group actions that are often confused with properly discontinuous actions.
Read more about Properly Discontinuous Action: Properly Discontinuous Action, Similar Properties
Famous quotes containing the words properly and/or action:
“In properly organized groups no faith is required; what is required is simply a little trust and even that only for a little while, for the sooner a man begins to verify all he hears the better it is for him.”
—George Gurdjieff (c. 1877–1949)
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