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arXiv · 2002.06536

Simple examples of non closable paranormal operators

Mohammed Hichem Mortad
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Abstract

In this note, we give an example of a densely defined non-closable paranormal operator. Then, we give another example of a densely defined closable paranormal operator whose closure fails to be paranormal. These two examples are simpler than those which first appeared in [1]. It is worth noticing that our first example tells us that the adjoint of a densely defined paranormal operator may have a trivial domain.

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Mohammed Hichem Mortad. 2020-02-16. Simple examples of non closable paranormal operators. https://arxiv.org/abs/2002.06536

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