# neighborhood retract

Let $X$ be a topological space^{} and $Y$ a subspace^{} of $X$. If there exists an open set $U$ such that $Y\subset U\subset X$ and $Y$ is a retract^{} of $U$, then we say $Y$ is a *neighborhood retract* of $X$.

Title | neighborhood retract |
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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 |