منابع مشابه
Set-ΛΛαppings on Dedekind Sets
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Associated to each ultrafilter U on ω and each map p : ω → ω is a Dedekind cut in the ultrapower ω/p(U). Blass has characterized, under CH, the cuts obtainable when U is taken to be either a p-point ultrafilter, a weakly-Ramsey ultrafilter or a Ramsey ultrafilter. Dobrinen and Todorcevic have introduced the topological Ramsey spaceR1. Associated to the spaceR1 is a notion of Ramsey ultrafilter ...
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Let S and T be hyperfinite sets in an N]-saturated nonstandard universe. The following are equivalent: m 1*1 ~ l (l) rff ~ • • (ii) There is a bijection from 5 onto T whose graph is Borel (over the internal subsets of S x T). This follows from somewhat more general results about analytic partial functions on hyperfinite sets, the proofs of which use Choquet's theorem on the capacitibility of an...
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ژورنال
عنوان ژورنال: Notre Dame Journal of Formal Logic
سال: 1989
ISSN: 0029-4527
DOI: 10.1305/ndjfl/1093635083