The ultrafilter and almost disjointness numbers
نویسندگان
چکیده
We prove that every MAD family can be destroyed by a proper forcing preserves P -points. With this result, we it is consistent ω 1 = u < , solving nearly 20 year old problem of Shelah, and Brendle. will also present simple proof result Blass Shelah the inequality s consistent.
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ژورنال
عنوان ژورنال: Advances in Mathematics
سال: 2021
ISSN: ['1857-8365', '1857-8438']
DOI: https://doi.org/10.1016/j.aim.2021.107805