Maximal almost disjoint families and pseudocompactness of hyperspaces

Abstract

We show that all Ψ-spaces associated to maximal almost disjoint families have pseudocompact Vietoris hyperspace if and only if MAc(P(ω)/fin) holds. We further study the question whether there is a maximal almost disjoint family whose hyperspace is pseudocompact and construct a consistent example of a maximal almost disjoint family of size ω2<c whose hyperspace is not pseudocompact.