CHARACTERIZATIONS OF STRICTLY SINGULAR AND STRICTLY COSINGULAR OPERATORS BY PERTURBATION CLASSES
نویسندگان
چکیده
منابع مشابه
Descriptive Set Theoretic Methods Applied to Strictly Singular and Strictly Cosingular Operators
The class of strictly singular operators originating from the dual of a separable Banach space is written as an increasing union of ω1 subclasses which are defined using the Schreier sets. A question of J. Diestel, of whether a similar result can be stated for strictly cosingular operators, is studied.
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A classification of weakly compact multiplication operators on L(Lp), 1 < p < ∞, is given. This answers a question raised by Saksman and Tylli in 1992. The classification involves the concept of `p-strictly singular operators, and we also investigate the structure of general `p-strictly singular operators on Lp . The main result is that if an operator T on Lp , 1 < p < 2, is `p-strictly singula...
متن کاملm at h . FA ] 3 1 M ay 2 00 8 DESCRIPTIVE SET THEORETIC METHODS APPLIED TO STRICTLY SINGULAR AND STRICTLY COSINGULAR OPERATORS
The class of strictly singular operators originating from the dual of a separable Banach space is written as an increasing union of ω1 subclasses which are defined using the Schreier sets. A question of J. Diestel, of whether a similar result can be stated for strictly cosingular operators, is studied.
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ژورنال
عنوان ژورنال: Glasgow Mathematical Journal
سال: 2011
ISSN: 0017-0895,1469-509X
DOI: 10.1017/s0017089511000346