A space $X$ is called Moscow, if for each open subset $U$ of $X$, the closure of $U$ in $X$ is the union of a family of $G_{δ}$-subsets of $X$ .
For example, every first countable $T_1$-space is Moscow.
I would love to see more examples.
2026-04-03 10:59:55.1775213995
Examples of Moscow spaces
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