Let $i:A \rightarrow X$ be a (closed ) cofibration (i.e a cofibration in the Strøm Model structure). For a subspace $B \subset A \subset X$, when is it true that $A/B \rightarrow X / B$ is a cofibration?
2026-05-15 20:54:53.1778878493
Collapse of a subspace - Cofibration
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