m at h . FA ] 3 1 M ay 2 00 8 DESCRIPTIVE SET THEORETIC METHODS APPLIED TO STRICTLY SINGULAR AND STRICTLY COSINGULAR OPERATORS
نویسنده
چکیده
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.
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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