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arXiv · 1803.09329

Julia operators and Halmos dilations

P. L. Robinson
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Abstract

We offer a simple direct proof of the unitarity of the Julia operator associated to a contraction $A$, from which follow the intertwining identity $(I - A A^*)^{1/2} A = A (I - A^* A)^{1/2}$ and the unitarity of Halmos dilations.

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P. L. Robinson. 2018-03-25. Julia operators and Halmos dilations. https://arxiv.org/abs/1803.09329

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