Many subalgebras of $\mathcal{P}(\omega)/\mathit{fin}$
General Topology
2026-04-07 v4 Logic
Abstract
In answer to a question on Mathoverflow we show that the Boolean algebra contains a family of subalgebras with the property that implies is a subalgebra of and if then is not embeddable into~. The proof proceeds by Stone duality and the construction of a suitable family of separable zero-dimensional compact spaces.
Cite
@article{arxiv.2303.08491,
title = {Many subalgebras of $\mathcal{P}(\omega)/\mathit{fin}$},
author = {Klaas Pieter Hart},
journal= {arXiv preprint arXiv:2303.08491},
year = {2026}
}
Comments
Version 2: added a description of a 40-years old answer to the original question Version 3: final version after referee's report; submitted to the journal. 2026-04-06: Fixed a few annoying typos