Let X be a topological spaceMathworldPlanetmath and Y a subspaceMathworldPlanetmathPlanetmath of X. If there exists a continuous mapMathworldPlanetmath r:XY such that r(y)=y for all yY, then we say Y is a retract of X and r is a retraction.

Title retract
Canonical name Retract
Date of creation 2013-03-22 12:16:06
Last modified on 2013-03-22 12:16:06
Owner rspuzio (6075)
Last modified by rspuzio (6075)
Numerical id 6
Author rspuzio (6075)
Entry type Definition
Classification msc 54C15
Related topic DeformationRetraction
Related topic PeriodOfMapping
Defines retraction