这里 A 和 X 是拓扑空间，是一个上纤维化（cofibration）如果它关于所有空间 Y 满足同伦延拓性质。因其对偶条件定义了纤维化，故有此名。上纤维化更一般的概念参见模型范畴一文。
英语百科
Cofibration 上纤维化
In mathematics, in particular homotopy theory, a continuous mapping
where A and X are topological spaces, is a cofibration if it satisfies the homotopy extension property with respect to all spaces Y. The name is because the dual condition, the homotopy lifting property, defines fibrations. For a more general notion of cofibration see the article about model categories.
![i\colon A \to X](/Images/godic/202501/05/db48b6a9eac8b69dec8e02b3f65496554646.png")
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