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arXiv · 2509.25493

On Hamiltonian stationarity of twisted Lagrangian tori in ${\mathbb{C}}^2$

Jingyi Chen·Patrik Coulibaly
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Abstract

Chekanov's exotic tori have been playing an important role in symplectic geometry as they are the only known examples of Lagrangian tori in ${\mathbb{C}}^2$ that are not Hamiltonian isotopic to a product torus. In this paper, we explore the differential geometry of a wider range of tori constructed by twisting simple closed planar curves, which include both certain product tori and Chekanov's exotic tori. In particular, we investigate the minimality of area of such twisted tori under Hamiltonian deformations and show that the only minimal twisted tori are the product ones. This tells us that Chekanov's exotic tori are not area minimal in their Hamiltonian isotopy classes.

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Jingyi Chen, Patrik Coulibaly. 2025-09-29. On Hamiltonian stationarity of twisted Lagrangian tori in ${\mathbb{C}}^2$. https://arxiv.org/abs/2509.25493

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