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Total subspaces in dual Banach spaces which are not norming

Mikhail I. Ostrovskii
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Abstract

The main result: the dual of separable Banach space $X$ contains a total subspace which is not norming over any infinite dimensional subspace of $X$ if and only if $X$ has a nonquasireflexive quotient space with the strictly singular quotient mapping.

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Mikhail I. Ostrovskii. 1993-03-29. Total subspaces in dual Banach spaces which are not norming. https://arxiv.org/abs/math/9303204

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