Entropy Rigidity for Maximal Representations

Zhufeng Yao

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arXiv · 2601.03585

Entropy Rigidity for Maximal Representations

Zhufeng Yao

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Abstract

Let $\Gamma\subset \mathsf{PSL}(2,\mathbb{R})$ be a lattice and $\rho:\Gamma\to \mathsf{Sp}(2n,\mathbb{R})$ be a maximal representation. We show that $\rho$ satisfies a measurable $(1,1,2)-$hypertransversality condition. With this we define a measurable Gromov product and the Bowen-Margulis-Sullivan measure associated to the unstable Jacobian introduced by Pozzetti, Sambarino and Wienhard. As a main application, we prove a strong entropy rigidity result for $\rho$.

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BibTeX RIS

Zhufeng Yao. 2026-01-07. Entropy Rigidity for Maximal Representations. https://arxiv.org/abs/2601.03585

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