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arXiv · 2504.12212

Idempotent compatible maps and discrete integrable systems on the triangular lattice

Pavlos Kassotakis·Maciej Nieszporski
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Abstract

We present three equivalence classes of rational non-invertible multidimensional compatible maps. These maps turns out to be idempotent and by construction they admit birational partial inverses (companion maps) which are Yang-Baxter maps. The maps in question can be reinterpreted as systems of difference equations defined on the edges of the $\mathbb{Z}^2$ graph. Finally, we associate these compatible systems of difference equations with integrable difference equations defined on the triangular lattice $Q(A2)$.

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Pavlos Kassotakis, Maciej Nieszporski. 2025-04-16. Idempotent compatible maps and discrete integrable systems on the triangular lattice. https://arxiv.org/abs/2504.12212

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