The Cofinal Strong Chang Conjecture from Models of Determinacy
Logic
2026-05-28 v1
Abstract
In chapter 9 of his book "The Axiom of Determinacy, Forcing Axioms, and the Nonstationary Ideal", Woodin shows how to force the Strong Chang Conjecture over models of determinacy using . We show here how a modification of the proof implies that such extensions actually verify the stronger cofinal version of the conjecture. This stronger version has important consequences on the semi-properness of small forcing, allowing us to prove the consistency of the theory "ZFC + Namba forcing is semiproper + ". We then use the constructions of this proof to also show that Woodin axiom implies the conjecture.
Cite
@article{arxiv.2605.28492,
title = {The Cofinal Strong Chang Conjecture from Models of Determinacy},
author = {Corentin Lagadec},
journal= {arXiv preprint arXiv:2605.28492},
year = {2026}
}
Comments
17 pages