neighborhood retract

Let X be a topological spaceMathworldPlanetmath and Y a subspaceMathworldPlanetmath of X. If there exists an open set U such that YUX and Y is a retractMathworldPlanetmath of U, then we say Y is a neighborhood retract of X.

Title neighborhood retract
Canonical name NeighborhoodRetract
Date of creation 2013-03-22 14:39:41
Last modified on 2013-03-22 14:39:41
Owner rspuzio (6075)
Last modified by rspuzio (6075)
Numerical id 5
Author rspuzio (6075)
Entry type Definition
Classification msc 54A99