کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
4660127 1344351 2011 6 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Ordinal remainders of ψ-spaces
موضوعات مرتبط
مهندسی و علوم پایه ریاضیات هندسه و توپولوژی
پیش نمایش صفحه اول مقاله
Ordinal remainders of ψ-spaces
چکیده انگلیسی

We consider which ordinals, with the order topology, can be Stone–Čech remainders of which spaces of the form ψ(κ,M), where ω⩽κ is a cardinal number and M⊂ω[κ] is a maximal almost disjoint family of countable subsets of κ (MADF). The cardinality of the continuum, denoted c, and its successor cardinal, c+, play important roles. We show that if κ>c+, then no ψ(κ,M) has any ordinal as a Stone–Čech remainder. If κ⩽c then for every ordinal δ<κ+ there exists Mδ⊂ω[κ], a MADF, such that βψ(κ,Mδ)∖ψ(κ,Mδ) is homeomorphic to δ+1. For κ=c+, βψ(κ,Mδ)∖ψ(κ,Mδ) is homeomorphic to δ+1 if and only if c+⩽δ

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Topology and its Applications - Volume 158, Issue 14, 1 September 2011, Pages 1852-1857