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arXiv 0904.0816math.LO
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MAD系列和SANE播放器

MAD Families and SANE Player

Saharon Shelah

摘要:

我们抛出一些光的问题:是否有一个MAD家庭(=一个家庭的无限子集的N,任何两个的交集是有限的),这是完全可分的(即任何X subseteq N是包括在一个有限联盟的成员的家庭或包括一个成员的家庭)。证明了:(a)如果2^{aleph_0} < aleph_omega,则存在这样一个族;(b)如果不存在这样的族,则与pcf有关的某些情形成立,其一致性是大的。

英文摘要:

We throw some light on the question: is there a MAD family (= a family of infinite subsets of N, the intersection of any two is finite) which is completely separable (i.e. any X subseteq N is included in a finite union of members of the family or include a member of the family). We prove that it is hard to prove the consistency of the negation: (a) if 2^{aleph_0} < aleph_omega, then there is such a family (b) if there is no such families then some situation related to pcf holds whose consistency is large.

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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