On Ginsburg-Isbell derivatives and ranks of metric spaces
The author considers metric spaces for which there exists a countable ordinal \(\alpha\) such that the \(\alpha\) th successive Ginsburg-Isbell derivative of the metric uniformity contains every open cover of the space. He shows that a separable metric space has this property if, and only if, it is complete and \(\sigma\)-compact.
complete \(\sigma \) -compact separable metric space
\(\alpha \) th successive Ginsburg-Isbell derivative
scientific article; zbMATH DE number 3890331
scientific article