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arXiv · 2302.04631

The intersection of complemented submodules is not complemented

Koen van den Dungen·Bram Mesland·Adam Rennie
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Abstract

We show by (counter)example that the intersection of complemented submodules in a Hilbert $C^*$-module is not necessarily complemented, answering an open question from [MR].

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Koen van den Dungen, Bram Mesland, Adam Rennie. 2023-02-07. The intersection of complemented submodules is not complemented. https://doi.org/10.1016/j.jmaa.2023.127002

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