Blog Archives

Topic Archive: wPFA

Set theory seminarFriday, March 18, 201610:00 amGC 6417

Ralf Schindler

wPFA

University of M√ľnster

We isolate a new forcing axiom, ${\rm wPFA}$, which is strictly between ${\rm BPFA}$ and ${\rm PFA}$. ${\rm wPFA}$ is equiconsistent with a remarkable cardinal, it implies the failure of $\square_{\omega_1}$, but it is compatible with $\square_\kappa$ for all $\kappa \geq \omega_2$. This is part of joint work with J. Bagaria and V. Gitman.