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arXiv · 1803.10942

A note on Huijsmans-de Pagter problem in ordered Banach algebras

Roman Drnovšek
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Abstract

We give an example of a positive element $a$ in some ordered Banach algebra $A$ such that its spectrum is equal to $\{1\}$ and it is not greater than or equal to the unit element of $A$.

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Roman Drnovšek. 2018-03-29. A note on Huijsmans-de Pagter problem in ordered Banach algebras. https://arxiv.org/abs/1803.10942

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