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arXiv · 1706.01904

The Non-Proper Dissipative Extensions of a Dual Pair

Christoph Fischbacher
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Abstract

We consider dissipative operators $A$ of the form $A=S+iV$, where both $S$ and $V\geq 0$ are assumed to be symmetric but neither of them needs to be (essentially) selfadjoint. After a brief discussion of the relation of the operators $S\pm iV $to dual pairs with the so called common core property, we present a necessary and suffcient condition for any extension of $A$ with domain contained in $\mathcal{D}((S-iV)^*)$ to be dissipative. We will discuss several special situations in which this condition can be expressed in a particularly nice form -- accessible to direct computations. Examples involving ordinary differential operators are given.

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Christoph Fischbacher. 2017-06-06. The Non-Proper Dissipative Extensions of a Dual Pair. https://arxiv.org/abs/1706.01904

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