PFA and the definability of the nonstationary ideal

Abstract

We produce, relative to a $\mathsf{ZFC}$ model with a supercompact cardinal, a $\mathsf{ZFC}$ model of the Proper Forcing Axiom in which the nonstationary ideal on ${\omega }_1$ is ${\Pi }_1$-definable in a parameter from $H_{{\aleph }_2}$.

References in corpus (1)

• Forcing Axioms and the Definabilty of the Nonstationary Ideal on ${\omega }_1$