Jónsson cardinals, Erdős cardinals, and the core model
Jónsson cardinals, Erdős cardinals, and the core model
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DOI:
10.2307/2586619
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发表时间:
1999-09
影响因子:
0.6
通讯作者:
W. Mitchell
中科院分区:
文献类型:
--
作者:
W. Mitchell
Abstract We show that if there is no inner model with a Woodin cardinal and the Steel core model K exists, then every Jónsson cardinal is Ramsey in K, and every δ-Jónsson cardinal is δ5-Erdős in K. In the absence of the Steel core model K we prove the same conclusion for any model L[] such that either V = L[] is the minimal model for a Woodin cardinal, or there is no inner model with a Woodin cardinal and V is a generic extension of L[]. The proof includes one lemma of independent interest: If V = L[A], where A ⊂ κ and κ is regular, then L κ[A] is a Jónsson algebra. The proof of this result. Lemma 2.5, is very short and entirely elementary.