Submaximal spaces and cardinal invariants
Abstract
We give a combinatorial characterization of countable submaximal subspaces of 2. Using a parametrized version of Mathias forcing, we prove that there exists a countable submaximal subspace of 2ω1 whilst c=ω2. Combining this with previous results, we construct a disjointly tight countable irresolvable space of weight <c, answering a question of Bella and Hrus\'ak.
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