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arXiv · 2404.08386

Criteria for algebraic operators to be unitary

Zenon Jan Jablonski·Il Bong Jung·Jan Stochel
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Abstract

Criteria for an algebraic operator $T$ on a complex Hilbert space $\mathcal{H}$ to be unitary are established. The main one is written in terms of the convergence of sequences of the form $\{\|T^nh\|\}_{n=0}^{\infty}$ with $h\in \mathcal{H}$. Related questions are also discussed.

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Zenon Jan Jablonski, Il Bong Jung, Jan Stochel. 2024-04-12. Criteria for algebraic operators to be unitary. https://arxiv.org/abs/2404.08386

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