General topology Constructions of spaces Concept
Disjoint union topology
Summary
The disjoint union topology is the natural topology on a disjoint union of topological spaces. A set is open in it exactly when its part in each piece is open in that piece. It makes the disjoint union the coproduct in the category of topological spaces. It is the final topology for the inclusions of the pieces.
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About this page
| Tag | ZXJKSB30WF |
|---|---|
| URI | m2://ZXJKSB30WF |
| Kind | concept |
| Writing | W0 stub |
| MSC | 54B99, 54B30 |
| Specializes | Final topology |
| Same as | |
| Changed | 2 November 2026 |
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