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arXiv · 2506.03838

On the domination of surface-group representations in $\mathrm{PU}(2,1)$

Abstract

This article explores surface-group representations into the complex hyperbolic group $\mathrm{PU}(2,1)$ and presents domination results for a special class of representations called $T$-bent representations. Let $S_{g,k}$ be a punctured surface of negative Euler characteristic. We prove that for a $T$-bent representation $\rho: \pi_1(S_{g,k}) \rightarrow \mathrm{PU}(2,1)$, there exists a discrete and faithful representation $\rho_0: \pi_1(S_{g,k}) \rightarrow \mathrm{PO}(2,1)$ that dominates $\rho$ in the Bergman translation length spectrum, while preserving the lengths of the peripheral loops.

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Pabitra Barman, Krishnendu Gongopadhyay. 2025-06-04. On the domination of surface-group representations in $\mathrm{PU}(2,1)$. https://arxiv.org/abs/2506.03838

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