= Properly discontinuous group action
= Properly discontinuous
{synonym}
= Properly discontinuously
{synonym}
An action is properly discontinuous when every compact set meets only finitely many of its translates. For an isometric action on a proper metric space, this gives the finiteness needed to extract a constant group element from a sequence with bounded source and target.
For a discrete <group action> on a locally compact space, a standard proper-discontinuity condition is that only finitely many group elements translate a given compact set to meet itself.
Back to article page
