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arXiv · 2302.00830

A note on connectedness of Blaschke products

Yue Xin·Bingzhe Hou
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Abstract

Consider the space $\mathcal{F}$ of all inner functions on the unit open disk under the uniform topology, which is a metric topology induced by the $H^{\infty}$-norm. In the present paper, a class of Blaschke products, denoted by $\mathcal{H}_{SC}$, is introduced. We prove that for each $B\in\mathcal{H}_{SC}$, $B$ and $zB$ belong to the same path-connected component of $\mathcal{F}$. It plays an important role of a method to select a fine subsequence of zeros. As a byproduct, we obtain that each Blaschke product in $\mathcal{H}_{SC}$ has an interpolating and one-component factor.

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Yue Xin, Bingzhe Hou. 2023-02-02. A note on connectedness of Blaschke products. https://arxiv.org/abs/2302.00830

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