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arXiv · 1512.07838

On the sum of a narrow and a compact operators

Volodymyr Mykhaylyuk
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Abstract

Our main technical tool is a principally new property of compact narrow operators which works for a domain space without an absolutely continuous norm. It is proved that for every Köthe $F$-space $X$ and for every locally convex $F$-space $Y$ the sum $T_1+T_2$ of a narrow operator $T_1:X\to Y$ and a compact narrow operator $T_2:X\to Y$ is a narrow operator. This gives a positive answers to questions asked by M.~Popov and B.~Randrianantoanina (\cite[Problem 5.6 and Problem 11.63]{PR})

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Volodymyr Mykhaylyuk. 2015-12-23. On the sum of a narrow and a compact operators. https://arxiv.org/abs/1512.07838

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