# Retraction

From Encyclopedia of Mathematics

A continuous mapping $f$ of a topological space $X$ into a subspace $A$ which is the identity on $A$, *i.e.* is such that $f(x)=x$ for all $x\in A$.

Cf. Retract of a topological space for more information and references.

**How to Cite This Entry:**

Retraction.

*Encyclopedia of Mathematics.*URL: http://encyclopediaofmath.org/index.php?title=Retraction&oldid=53670

This article was adapted from an original article by M.I. Voitsekhovskii (originator), which appeared in Encyclopedia of Mathematics - ISBN 1402006098. See original article