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arXiv · 2006.05802

The perturbation classes problem for subprojective and superprojective Banach spaces

Manuel González·Javier Pello·Margot Salas-Brown
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Abstract

We show that the perturbation class for the upper semi-Fredholm operators between two Banach spaces X and Y coincides with the strictly singular operators when X is subprojective and that the perturbation class for the lower semi-Fredholm operators coincides with the strictly cosingular operators when Y is superprojective. Similar results were previously obtained under stronger conditions for X and Y.

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Manuel González, Javier Pello, Margot Salas-Brown. 2020-06-10. The perturbation classes problem for subprojective and superprojective Banach spaces. https://doi.org/10.1016/j.jmaa.2020.124191

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