On ultraproducts of Boolean algebras and irr
نویسنده
چکیده
Anotated Content §1 Consistent inequality [We prove the consistency of irr(i<κ B i /D) < i<κ irr(B i)/D where D is an ultrafilter on κ and each B i is a Boolean Algebra. This solves the last problem of this form from the Monk's list of problems in [M2], that is number 35. The solution applies to many other properties, e.g. Souslinity.] §2 Consistency for small cardinals [We get similar results with κ = ℵ 1 (easily we cannot have it for κ = ℵ 0) and Boolean Algebras B i (i < κ) of cardinality < ω 1 .] This article continues Magidor Shelah [MgSh 433] and Shelah Spinas [ShSi 677], but does not rely on them: see [M2] on background. I would like to thank Alice Leonhardt for the beautiful typing.
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ورودعنوان ژورنال:
- Arch. Math. Log.
دوره 42 شماره
صفحات -
تاریخ انتشار 2003