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arXiv · 2607.13794

Complete functional calculus bounds for $\rho$-contractions

Michael Hartz·Jens de Vries
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Abstract

Let $T$ be a $\rho$-contraction on a Hilbert space. We establish sharp bounds for the functional calculus of $T$ for matrix-valued analytic functions on the unit disc. These are complete versions of bounds established by Drury and by Schwenninger and the second author.

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Michael Hartz, Jens de Vries. 2026-07-15. Complete functional calculus bounds for $\rho$-contractions. https://arxiv.org/abs/2607.13794

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