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arXiv · 2606.28594

A Sharp Kato-Rosenblum Type Theorem for Unbounded n-Tuples

Rishabh Bhutani·Dan Virgil Voiculescu
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Abstract

We prove a generalization for commuting $n$-tuples of unbounded self-adjoint operators and the Lorentz $(n,1)$ ideal,$n \ge 3$, of the Kato-Rosenblum theorem. The result is derived from earlier work for bounded operators [8]. Also, a very weak result for $n=2$ unbounded operators and other additional results are obtained.

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Rishabh Bhutani, Dan Virgil Voiculescu. 2026-06-26. A Sharp Kato-Rosenblum Type Theorem for Unbounded n-Tuples. https://arxiv.org/abs/2606.28594

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