Article
Keywords:
pseudo-radial spaces; prime spaces; sub pseudo-radial spaces; tightness; Martin's Axiom
Summary:
It is proved that, under the Martin's Axiom, every $T_1$-space with countable tightness is a subspace of some pseudo-radial space. We also give several characterizations of subspaces of pseudo-radial spaces and conclude that being a subspace of a pseudo-radial space is a local property.
References:
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