General topology Separation axioms Concept
Perfectly normal space
Summary
A perfectly normal space is a normal space in which every closed set is a countable intersection of open sets. Equivalently, every closed set is the zero set of a continuous real function. Every perfectly normal space is completely normal. Every metric space is perfectly normal.
Further reading
About this page
| Tag | VK3ZMD1BCP |
|---|---|
| URI | m2://VK3ZMD1BCP |
| Kind | concept |
| Writing | W0 stub |
| MSC | 54D15 |
| Specializes | Completely normal space |
| Changed | 2 November 2026 |
Markdown · JSON · Edit on GitHub
What this page needs for W1
- an inventory row: the row of the inventory that the node accounts for (0 of 1)
- a source with a locator (0 of 1)
The writing levels say how complete the text of a page is. They do not measure its truth.