arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 1003.6058math.GNmath.LO
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伪紧性的进一步推广

More generalizations of pseudocompactness

Paolo Lipparini

摘要:

我们引入了一个覆盖的概念,取决于两个基数,我们称之为$\mathcal O $ - $ [ μ, λ]$ -紧性,它包括伪紧性和许多其他推广的伪紧性。对于吉洪诺夫空间,伪紧性等价于$\mathcal O $ - $ [ ω, ω ]$ -紧性。给出了$\mathcal O $ - $ [ μ, λ]$ -紧性的几个刻画,并讨论了它与$D$ -伪紧性的关系,其中$D$是超滤子.我们分析了上述概念在产品中的行为。最后,我们表明,我们的结果持有一个更一般的框架,其中紧性定义相对于一个任意家庭的子集的一些拓扑空间$X$。

英文摘要:

We introduce a covering notion depending on two cardinals, which we call $\mathcal O $-$ [ μ, λ]$-compactness, and which encompasses both pseudocompactness and many other generalizations of pseudocompactness. For Tychonoff spaces, pseudocompactness turns out to be equivalent to $\mathcal O $-$ [ ω, ω ]$-compactness. We provide several characterizations of $\mathcal O $-$ [ μ, λ]$-compactness, and we discuss its connection with $D$-pseudocompactness, for $D$ an ultrafilter. We analyze the behaviour of the above notions with respect to products. Finally, we show that our results hold in a more general framework, in which compactness properties are defined relative to an arbitrary family of subsets of some topological space $X$.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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