absolute retract

A topological space $X$ is an absolute retract if, for every embedding of $X$ as a closed subset of a normal space $Y$, the image of $X$ is a retract of $Y$.

A topological space $X$ is an if, for every embedding of $X$ as a closed subset of a normal space $Y$, the image of $X$ is a neighborhood retract of $Y$.

Title	absolute retract
Canonical name	AbsoluteRetract
Date of creation	2013-03-22 14:39:35
Last modified on	2013-03-22 14:39:35
Owner	rspuzio (6075)
Last modified by	rspuzio (6075)
Numerical id	5
Author	rspuzio (6075)
Entry type	Definition
Classification	msc 54A99
Defines	absolute neighborhood retract