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A separable L-embedded Banach space has property (X) and is therefore the unique predual of its dual

Hermann Pfitzner
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Abstract

In this note the following is proved. Separable L-embedded spaces - that is separable Banach spaces which are complemented in their biduals such that the norm between the two complementary subspaces is additive - have property (X) which, by a result of Godefroy and Talagrand, entails uniqueness of the space as a predual.

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Hermann Pfitzner. 2005-07-18. A separable L-embedded Banach space has property (X) and is therefore the unique predual of its dual. https://arxiv.org/abs/math/0507354

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