On pseudo-radial spaces. (English) Zbl 0587.54007

The authors introduce and study a new critical invariant called quasicharacter, which is a modification of tightness. The attention is focused on the class of pseudo-radial spaces (pseudo-radial \(=\) ”sequential wrt. well-ordered nets”). Sample results: quasi-character and tightness coincide for: radial (FrĂ©chet wrt. well-ordered nets) \(T_ 1\)-spaces, for pseudo-radial monolithic \(T_ 2\)-spaces, and (assuming GCH) for pseudo-radial compact \(T_ 2\)-spaces.
Reviewer: K.P.Hart


54A25 Cardinality properties (cardinal functions and inequalities, discrete subsets)
54D55 Sequential spaces
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