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:
“For the superior morality of which we hear so much, we too would desire to be thankful: at the same time, it were but blindness to deny that this superior morality is properly rather an inferior criminality produced not by greater love of Virtue, but by greater perfection of Police; and of that far subtler and stronger Police, called Public Opinion.”
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