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arXiv · 2605.30445

Blaschke Products Sharing a Welding Homeomorphism

Kirill Lazebnik
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Abstract

Given two Blaschke products $A$, $B$ of the same degree, a \emph{welding homeomorphism} of $A$, $B$ is a circle homeomorphism $k: \mathbb{T} \rightarrow \mathbb{T}$ satisfying $A\circ k=B$ on $\mathbb{T}$. We show that any two pairs of Blaschke products sharing a welding homeomorphism must factor through a common pair of Blaschke products, and we give a criterion for detecting whether two Blaschke products admit such a factorization.

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Kirill Lazebnik. 2026-05-28. Blaschke Products Sharing a Welding Homeomorphism. https://arxiv.org/abs/2605.30445

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