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arXiv 0708.1979math.LO
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基数算术的进展

Advances in Cardinal Arithmetic

Saharon Shelah

摘要:

如果cf(kappa)= kappa,kappa^+< cf(lambda)= λ,则在I[lambda]中存在{delta<lambda:cf(delta)=kappa}的稳定子集S。此外,我们可以找到<C_delta:delta in S>,C_delta是lambda的俱乐部,otp(C_delta)=kappa,猜测俱乐部,对于每个alpha<lambda,我们有:{C_delta \cap alpha:alpha \in nacc(C_delta)}具有基数<lambda。此外,我们证明,例如,有一个固定的子集的S_{<aleph_1}(lambda)的基数cf(S_{<aleph_1}(lambda),subseteq)然后,我们证明了存在的好的过滤器,而不是正常的过滤器在ω_1上,他们是正常的过滤器与更大的域,这可以增加在发挥。它们可以帮助我们将aleph_1-complete过滤器上的情况转换为正常情况

英文摘要:

If cf(kappa) = kappa, kappa^+< cf(lambda) = λ, then there is a stationary subset S of {delta<lambda:cf(delta)=kappa} in I[lambda]. Moreover, we can find <C_delta :delta in S>, C_delta a club of lambda, otp(C_delta)=kappa, guessing clubs and for each alpha<lambda we have: {C_delta \cap alpha: alpha \in nacc(C_delta)} has cardinality <lambda. Also, we prove that e.g. there is a stationary subset of S_{<aleph_1}(lambda) of cardinality cf(S_{<aleph_1}(lambda),subseteq) Then we prove the existence of nice filters when instead being normal filters on omega_1 they are normal filters with larger domains, which can increase during a play. They can help us transfer situation on aleph_1-complete filters to normal ones

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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