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arXiv · 1301.0241

A Criterion for the Normality of Unbounded Operators and Applications to Self-adjointness

Mohammed Hichem Mortad
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Abstract

In this paper we give and prove a criterion for the normality of unbounded closed operators, which is a sort of a maximality result which will be called "double maximality". As applications, we show, under some assumptions, that the sum of two symmetric operators is essentially self-adjoint; and that the sum of two unbounded normal operators is essentially normal. Some other important results are also established.

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Mohammed Hichem Mortad. 2013-01-11. A Criterion for the Normality of Unbounded Operators and Applications to Self-adjointness. https://arxiv.org/abs/1301.0241

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