If $X$ is normal and $F_1$, $F_2$ are disjoint closed subsets, then there exist open subsets $W_1$ ⊃ $F_1$, $W_2$ ⊃ $F_2$, whose closures are disjoint

score 85 · Answer 13 · 2026-04-22 22:18:43

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Example 2, Sec. 31, in Munkres' TOPOLOGY, 2nd ed: Normality of $\mathbb{R}_l$ --- Why are these two sets disjoint?

Published on 22 Apr 2026 - 22:18

score 892 · Answer 14 · 2026-05-11 04:37:46

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Separatedness of open subscheme of affine schemes

Published on 11 May 2026 - 4:37

score 77 · Answer 15 · 2026-04-14 15:55:46

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$X$ is regular iff $Y$ is regular

Published on 14 Apr 2026 - 15:55

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If $X$ is normal and $F_1$, $F_2$ are disjoint closed subsets, then there exist open subsets $W_1$ ⊃ $F_1$, $W_2$ ⊃ $F_2$, whose closures are disjoint

Example 2, Sec. 31, in Munkres' TOPOLOGY, 2nd ed: Normality of $\mathbb{R}_l$ --- Why are these two sets disjoint?

Separatedness of open subscheme of affine schemes

$X$ is regular iff $Y$ is regular

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