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arXiv · 2608.06330

Domain Characterizations of Strong Commutativity\break of Unbounded Self-Adjoint Operators

Konrad Schmüdgen
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Abstract

Let $A$ and $B$ be unbounded self-adjoint operators on a Hilbert space. Suppose that there exists a dense linear subspace $D\subseteq D(AB)\cap D(BA)$ such that $ABx=BAx$ for $x \in D$. We give some characterizations of the strong commutativity of $A$ and $B$ in terms of domain equalities.

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Konrad Schmüdgen. 2026-08-06. Domain Characterizations of Strong Commutativity\break of Unbounded Self-Adjoint Operators. https://arxiv.org/abs/2608.06330

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