Forcing Axioms and construction schemes
Abstract
We continue the development of the theory of construction schemes over ω1 as introduced by the third author by studying their relation with forcing axioms. Formally, we introduce the cardinals mnF and use the consistency of m2F>ω1 to prove a fundamental result relating gaps and almost disjoint families over ω. The cardinals mF are also used to prove some limiting results for contstruction schemes, some of which answer questions from schemescruz. Finally, we show that PID implies the non-existence of 2-capturing schemes.
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