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arXiv · 2601.08593

Deformation and perturbative rigidity near de la Llave examples

Andrey Gogolev·Martin Leguil
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Abstract

De la Llave's examples are Anosov diffeomorphisms on the four-torus $\mathbb{T}^4$ with constant Lyapunov spectrum, yet they are not $C^{1}$-conjugate to the linear model or to each other. Nevertheless, we show that such examples are ``locally exceptional'': we prove deformation and local rigidity for generic diffeomorphisms in proximity of de la Llave's examples.

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Andrey Gogolev, Martin Leguil. 2026-01-13. Deformation and perturbative rigidity near de la Llave examples. https://arxiv.org/abs/2601.08593

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