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arXiv · 1609.05326

Preduals and complementation of spaces of bounded linear operators

Eusebio Gardella·Hannes Thiel
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Abstract

For Banach spaces X and Y, we establish a natural bijection between preduals of Y and preduals of L(X,Y) that respect the right L(X)-module structure. If X is reflexive, it follows that there is a unique predual making L(X) into a dual Banach algebra. This removes the condition that X have the approximation property in a result of Daws. We further establish a natural bijection between projections that complement Y in its bidual and L(X)-linear projections that complement L(X,Y) in its bidual. It follows that Y is complemented in its bidual if and only if L(X,Y) is (either as a module or as a Banach space). Our results are new even in the well-studied case of isometric preduals.

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Eusebio Gardella, Hannes Thiel. 2016-09-17. Preduals and complementation of spaces of bounded linear operators. https://arxiv.org/abs/1609.05326

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