Semi-Cohen Versus Cohen Algebras
Jindřich Zapletal
Abstract
We show that there are semi-Cohen Boolean algebras which cannot be completely embedded into Cohen Boolean algebras. Using the ideas from this proof, we give a simpler argument for a theorem of S. Koppelberg and S. Shelah, stating that there are complete subalgebras of Cohen algebras which are not Cohen themselves.
Create a lesson
Related papers
Pseudofinite abelian groups and asymptotic classes of finite abelian groups
Carlos Cordoba-Caycedo, Dario Garcia
Spectral Theory and Descriptive Combinatorics for Non-Regular Borel pmp Graphs
Cecelia Higgins, Pieter Spaas, Sofia Torelli
The strength of the minimum principle in constructive reverse mathematics
Tatsuji Kawai
Independence of premise for intuitionistic Zermelo-Fraenkel set theory
Patrick Uftring
Condensed Whitehead Problem
Spencer Unger, Jerry Wei
Points and their multiples on curves in powers of simple abelian varieties
David J. Smith