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arXiv · 2606.24029

Schur functions on a rhombic lattice

Daniel Alpay·Angel Fuerte Perez·Dan Volok
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Abstract

We extend the study of discrete analytic (DA) Schur functions to rhombic lattices, utilizing suitably defined shift operators. There is a number of important differences with the classical case, including eigenvalues of the backward shift operator. As an application we solve a basic interpolation problem in a weighted Hardy space of DA functions, introducing a discrete counterpart of the Blaschke factor.

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Daniel Alpay, Angel Fuerte Perez, Dan Volok. 2026-06-23. Schur functions on a rhombic lattice. https://arxiv.org/abs/2606.24029

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