Fat sets and saturated ideals
نویسندگان
چکیده
منابع مشابه
Fat sets and saturated ideals
We strengthen a theorem of Gitik and Shelah [6] by showing that if κ is either weakly inaccessible or the successor of a singular cardinal and S is a stationary subset of κ such that NSκ S is saturated then κ \S is fat. Using this theorem we derive some results about the existence of fat stationary sets. We then strengthen some results due to Baumgartner and Taylor [2], showing in particular th...
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We prove the following: (1) If κ is weakly inaccessible then NSκ is not κ+-saturated. (2) If κ is weakly inaccessible and θ < κ is regular then NSθ κ is not κ +saturated. (3) If κ is singular then NS κ+ is not κ++-saturated. Combining this with previous results of Shelah, one obtains the following: (A) If κ > א1 then NSκ is not κ+-saturated. (B) If θ+ < κ then NSθ κ is not κ +-saturated.
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ژورنال
عنوان ژورنال: Journal of Symbolic Logic
سال: 2003
ISSN: 0022-4812,1943-5886
DOI: 10.2178/jsl/1058448442