Topological retraction Deformation retraction Let be a subspace and the inclusion. A deformation retraction is a is a retraction, i.e. , such that homotopy Hence in Category of topological spaces, is a left inverse of , but in Naïve homotopy category is a proper inverse of . Properties Clearly if is a deformation retract of , . Thus a deformation retraction is a stronger kind of Homotopy equivalence. tidy | en | sembr