arXiv math/98021351998-02-15math.LOmath.GN

On tightness and depth in superatomic Boolean algebras

Saharon Shelah, Otmar Spinas

发表信息：: Proc. Amer. Math. Soc. 127 No. 12 (1999) 3475--3480

英文摘要：

We introduce a large cardinal property which is consistent with L and show that for every superatomic Boolean algebra B and every cardinal lambda with the large cardinal property, if tightness^+(B) >= lambda^+, then depth (B) >= lambda. This improves a theorem of Dow and Monk.

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