English

On $\omega_3$-chains in P($\omega_1$) mod finite

Logic 2011-10-18 v2

Abstract

We prove that if there exists a simplified (ω1,2)(\omega_1,2)-morass, then there is a ccc forcing which adds an ω3\omega_3-chain in P(ω1\omega_1) mod finite and a ccc forcing which adds a family of ω3\omega_3-many strongly almost disjoint functions from ω1\omega_1 to ω\omega. The idea is to use a finite support iteration of countable forcings which is not linear but three-dimensional.

Keywords

Cite

@article{arxiv.0811.0548,
  title  = {On $\omega_3$-chains in P($\omega_1$) mod finite},
  author = {Bernhard Irrgang},
  journal= {arXiv preprint arXiv:0811.0548},
  year   = {2011}
}

Comments

There are some gaps in the proof which I am unable to fix

R2 v1 2026-06-21T11:38:07.088Z