Abstract: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.
Keywords: pseudo-radial spaces, prime spaces, sub pseudo-radial spaces, tightness, Martin's Axiom
AMS Subject Classification: 54A35, 54B05, 54D99