Analytic Ideals and Cofinal Types
نویسندگان
چکیده
We study the class of analytic ideals on the set of natural numbers ordered under Tukey reducibility. We consider mostly structural issues: characterization of ideals which are Tukey above w”‘, extremal elements for the class of analytic P-ideals, etc. We prove that this class is very rich by embedding into it (P(N), (I,). We also study ideals associated to classical Banach spaces and ideals of compacts sets in a Polish space. @ 1999 Elsevier Science B.V. All rights reserved. AMS cluss~jication: Primary 04A15; 04A20; 28A05
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ورودعنوان ژورنال:
- Ann. Pure Appl. Logic
دوره 99 شماره
صفحات -
تاریخ انتشار 1999