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arXiv · 2203.14243

A polynomial approximation result for free Herglotz-Agler functions

Kenta Kojin
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Abstract

In this paper, we prove a noncommutative (nc for short) analog of Schwarz lemma for the nc Schur-Agler class and prove that the regular nc Schur-Agler class and the regular free Herglotz class are homeomorphic. Moreover, we give a characterization of regular free Herglotz functions. As an application, we will show that any regular free Herglotz functions can uniformly be approximated by regular Herglotz free polynomials.

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Kenta Kojin. 2022-03-27. A polynomial approximation result for free Herglotz-Agler functions. https://doi.org/10.4153/s0008439522000637

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