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arXiv · 2012.10683

Disjointly non-singular operators on Banach lattices

Manuel González·Antonio Martí nez-Abejón·Antonio Martinón
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Abstract

An operator $T$ from a Banach lattice $E$ into a Banach space is disjointly non-singular ($DN$-$S$, for short) if no restriction of $T$ to a subspace generated by a disjoint sequence is strictly singular. We obtain several results for $DN$-$S$ operators, including a perturbative characterization. For $E=L_p$ ($1< p<\infty$) we improve the results, and we show that the $DN$-$S$ operators have a different behavior in the cases $p=2$ and $p\neq 2$. As an application we prove that the strongly embedded subspaces of $L_p$ form an open subset in the set of all closed subspaces.

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Manuel González, Antonio Martí nez-Abejón, Antonio Martinón. 2020-12-19. Disjointly non-singular operators on Banach lattices. https://arxiv.org/abs/2012.10683

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