THE COLLECTIONWISE HAUSDORFF PROPERTY OF PRODUCTS OF TWO OR THREE SUBSPACES OF ORDINALS

被引：0
|
作者：
Hirata, Yasushi [1 ]
机构：
[1] Univ Tsukuba, Grad Sch Math, Tsukuba 3058571, Japan
来源：
HOUSTON JOURNAL OF MATHEMATICS | 2009年 / 35卷 / 03期
关键词：
Product; ordinal; stationary set; Pressing Down Lemma; collectionwise Hausdorff; MILD NORMALITY; OMEGA(1); OMEGA(2)(1);
D O I：
暂无
中图分类号：
O1 [数学];
学科分类号：
0701 ; 070101 ;
摘要：
It is known that every finite power of omega(1) is hereditarily collectionwise Hausdorff [6], [2]. And it is easy to see that there is a subspace of (omega + 1) x (omega(1) + 1) which is not collectionwise Hausdorff. We will prove that every product space of two subspaces of ordinals is collectionwise Hausdorff, but there is a product space of three subspaces of ordinals which is not collectionwise Hausdorff.
引用
收藏
页码：891 / 901
页数：11
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