Covering the Baire space by families which are not finitely dominating
Abstract
It is consistent (relative to ZFC) that the union of maxb,g many families in the Baire space which are not finitely dominating is not dominating. In particular, it is consistent that for each nonprincipal ultrafilter U, the cofinality of the reduced ultrapower ww/U is greater than maxb,g. The model is constructed by oracle chain condition forcing, to which we give a self-contained introduction.
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