σ-Entangled linear orders and narrowness of products of Boolean algebras
Volume 153 / 1997
Fundamenta Mathematicae 153 (1997), 199-275
DOI: 10.4064/fm-153-3-199-275
Abstract
We investigate σ-entangled linear orders and narrowness of Boolean algebras. We show existence of σ-entangled linear orders in many cardinals, and we build Boolean algebras with neither large chains nor large pies. We study the behavior of these notions in ultraproducts.
