Depth of Boolean Algebras
نویسندگان
چکیده
Suppose D is an ultrafilter on κ and λ = λ. We prove that if Bi is a Boolean algebra for every i < κ and λ bounds the Depth of every Bi, then the Depth of the ultraproduct of the Bi’s mod D is bounded by λ. We also show that for singular cardinals with small cofinality, there is no gap at all. This gives a partial answer to problem No. 12 in [?]. 2000 Mathematics Subject Classification. Primary: 06E05, 03G05. Secondary: 03E45.
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عنوان ژورنال:
- Notre Dame Journal of Formal Logic
دوره 52 شماره
صفحات -
تاریخ انتشار 2011