Forcing Axioms and construction schemes
Jorge Antonio Cruz Chapital, Osvaldo Guzman, Stevo Todorcevic
公開日: 2025/9/1
Abstract
We continue the development of the theory of construction schemes over $\omega_1$ as introduced by the third author by studying their relation with forcing axioms. Formally, we introduce the cardinals $\mathfrak{m}^n_{\mathcal{F}}$ and use the consistency of $\mathfrak{m}^2_\mathcal{F}>\omega_1$ to prove a fundamental result relating gaps and almost disjoint families over $\omega$. The cardinals $\mathfrak{m}_\mathcal{F}$ are also used to prove some limiting results for contstruction schemes, some of which answer questions from \cite{schemescruz}. Finally, we show that PID implies the non-existence of $2$-capturing schemes.