Extension operators and twisted sums of c 0 and C ( K ) spaces
نویسندگان
چکیده
منابع مشابه
Twisted Sums with C(k) Spaces
If X is a separable Banach space, we consider the existence of non-trivial twisted sums 0 → C(K) → Y → X → 0, where K = [0, 1] or ωω . For the case K = [0, 1] we show that there exists a twisted sum whose quotient map is strictly singular if and only if X contains no copy of `1. If K = ωω we prove an analogue of a theorem of Johnson and Zippin (for K = [0, 1]) by showing that all such twisted s...
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ژورنال
عنوان ژورنال: Journal of Functional Analysis
سال: 2018
ISSN: 0022-1236
DOI: 10.1016/j.jfa.2017.09.004