Ultrafilters on Ω
نویسنده
چکیده
We study the I-ultrafilters on ω, where I is a a collection of subsets of a set X , usually R or ω1. The I-ultrafilters usually contain the P -points, often as a small proper subset. We study relations between I-ultrafilters for various I, and closure of I-ultrafilters under ultrafilter sums. We consider, but do not settle, the question whether I-ultrafilters always exist.
منابع مشابه
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