Separable Banach space theory needs strong set existence axioms
نویسندگان
چکیده
منابع مشابه
Separable Banach Space Theory Needs Strong Set Existence Axioms
We investigate the strength of set existence axioms needed for separable Banach space theory. We show that a very strong axiom, Π1 comprehension, is needed to prove such basic facts as the existence of the weak-∗ closure of any norm-closed subspace of `1 = c0. This is in contrast to earlier work [6, 4, 7, 23, 22] in which theorems of separable Banach space theory were proved in very weak subsys...
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ژورنال
عنوان ژورنال: Transactions of the American Mathematical Society
سال: 1996
ISSN: 0002-9947,1088-6850
DOI: 10.1090/s0002-9947-96-01725-4