arXiv math/97032191997-03-15math.LO

Some independence results on reflection

James Cummings, Saharon Shelah

发表信息：: J. London Math. Soc. (2) 59 No. 1 (1999) 37--49

英文摘要：

We prove that there is a certain degree of independence between stationary reflection phenomena at different cofinalities; e.g. it is consistent that every stationary subset of S_1^3 reflects at a point of cofinality aleph_2 while every stationary subset of S^3_0 has a non-reflecting stationary subset

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