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arXiv · 2005.04873

Large cardinals and continuity of coordinate functionals of filter bases in Banach spaces

Tomasz Kania·Jarosław Swaczyna
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Abstract

Assuming the existence of certain large cardinal numbers, we prove that for every projective filter $\mathscr F$ over the set of natural numbers, $\mathscr{F}$-bases in Banach spaces have continuous coordinate functionals. In particular, this applies to the filter of statistical convergence, thereby we solve a problem by V. Kadets (at least under the presence of certain large cardinals). In this setting, we recover also a result of Kochanek who proved continuity of coordinate functionals for countably generated filters (Studia Math., 2012).

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Tomasz Kania, Jarosław Swaczyna. 2020-05-11. Large cardinals and continuity of coordinate functionals of filter bases in Banach spaces. https://doi.org/10.1112/blms.12415

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