Point-cofinite covers in the Laver model
نویسندگان
چکیده
منابع مشابه
Point-cofinite Covers in the Laver Model
Let S1(Γ,Γ) be the statement: For each sequence of point-cofinite open covers, one can pick one element from each cover and obtain a point-cofinite cover. b is the minimal cardinality of a set of reals not satisfying S1(Γ,Γ). We prove the following assertions: (1) If there is an unbounded tower, then there are sets of reals of cardinality b, satisfying S1(Γ,Γ). (2) It is consistent that all set...
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ژورنال
عنوان ژورنال: Proceedings of the American Mathematical Society
سال: 2010
ISSN: 0002-9939
DOI: 10.1090/s0002-9939-10-10407-9