کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
4660697 1344380 2009 8 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Examples from trees, related to discrete subsets, pseudo-radiality and ω-boundedness
موضوعات مرتبط
مهندسی و علوم پایه ریاضیات هندسه و توپولوژی
پیش نمایش صفحه اول مقاله
Examples from trees, related to discrete subsets, pseudo-radiality and ω-boundedness
چکیده انگلیسی

We construct some examples using trees. Some of them are consistent counterexamples for the discrete reflection of certain topological properties. All the properties dealt with here were already known to be non-discretely reflexive if we assume CH and we show that the same is true assuming the existence of a Suslin tree. In some cases we actually get some ZFC results. We construct also, using a Suslin tree, a compact space that is pseudo-radial but it is not discretely generated. With a similar construction, but using an Aronszajn tree, we present a ZFC space that is first countable, ω-bounded but is not strongly ω-bounded, answering a question of Peter Nyikos.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Topology and its Applications - Volume 156, Issue 4, 1 February 2009, Pages 775-782