- properly discontinuous group
- собственно разрывная группа
English-Russian scientific dictionary. 2008.
properly discontinuous group
Смотреть что такое "properly discontinuous group" в других словарях:
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.… … Wikipedia
Group action — This article is about the mathematical concept. For the sociology term, see group action (sociology). Given an equilateral triangle, the counterclockwise rotation by 120° around the center of the triangle acts on the set of vertices of the… … Wikipedia
Hyperbolic group — In group theory, a hyperbolic group, also known as a word hyperbolic group, Gromov hyperbolic group, negatively curved group is a finitely generated group equipped with a word metric satisfying certain properties characteristic of hyperbolic… … Wikipedia
Geometric group action — In mathematics, specifically geometric group theory, a geometric group action is a certain type of action of a discrete group on a metric space.DefinitionIn geometric group theory, a geometry is any proper, geodesic metric space. An action of a… … Wikipedia
Orbifold — This terminology should not be blamed on me. It was obtained by a democratic process in my course of 1976 77. An orbifold is something with many folds; unfortunately, the word “manifold” already has a different definition. I tried “foldamani”,… … Wikipedia
Covering space — A covering map satisfies the local triviality condition. Intuitively, such maps locally project a stack of pancakes above an open region, U, onto U. In mathematics, more specifically algebraic topology, a covering map is a continuous surjective… … Wikipedia
Ping-pong lemma — In mathematics, the ping pong lemma, or table tennis lemma, is any of several mathematical statements which ensure that several elements in a group acting on a set freely generate a free subgroup of that group.HistoryThe ping pong argument goes… … Wikipedia
Kazhdan's property (T) — In mathematics, a locally compact topological group G has property (T) if the trivial representation is an isolated point in its unitary dual equipped with the Fell topology. Informally, this means that if G acts unitarily on a Hilbert space and… … Wikipedia
List of mathematics articles (P) — NOTOC P P = NP problem P adic analysis P adic number P adic order P compact group P group P² irreducible P Laplacian P matrix P rep P value P vector P y method Pacific Journal of Mathematics Package merge algorithm Packed storage matrix Packing… … Wikipedia
James W. Cannon — (b. January 30, 1943) is an American mathematician working in the areas of low dimensional topology and geometric group theory. He is an Orson Pratt Professor of Mathematics at the Brigham Young University.Biographical dataJames W. Cannon was… … Wikipedia
Graph of groups — In geometric group theory, a graph of groups is an object consisting of a collection of groups indexed by the vertices and edges of a graph, together with a family of injective homomorphisms of the edge groups into the vertex groups.There is a… … Wikipedia
