The box product of countably many metrizable spaces need not be normal
The commuting of coreflectors in uniform spaces with completion
The functor σ²X
We disprove the existence of a universal object in several classes of spaces including the class of weakly Lindelöf Banach spaces.
The kernel operation on subsets of a -space
The one-point countable compactification of curve spaces and arc spaces
Tilings in topological spaces.