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arXiv · 1709.10218

Divergence, Undistortion and Hölder Continuous Cocycle Superrigidity for Full Shifts

Abstract

In this article, we will prove a full topological version of Popa's measurable cocycle superrigidity theorem for full shifts. More precisely, we prove that every Hölder continuous cocycle for the full shifts of every finitely generated group $G$ that has one end, undistorted elements and sub-exponential divergence function is cohomologous to a group homomorphism via a Hölder continuous transfer map if the target group is complete and admits a compatible bi-invariant metric. Using the ideas of Behrstock, Dru\c {t}u, Mosher, Mozes and Sapir, we show that the class of our acting groups is large including wide groups having undistorted elements and one-ended groups with strong thick of finite orders. As a consequence, irreducible uniform lattices of most of higher rank connected semisimple Lie groups, mapping class groups of $g$-genus surfaces with $p$-punches, $g\geq 2, p\geq 0$, Thompson group, $Aut(F_n)$, $Out(F_n)$, $n\geq3$, certain (2 dimensional)-Coxeter groups, and one-ended right-angled Artin groups are in our class. This partially extends the main result in our previous paper.

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BibTeXRIS

Nhan-Phu Chung, Yongle Jiang. 2017-10-09. Divergence, Undistortion and Hölder Continuous Cocycle Superrigidity for Full Shifts. https://arxiv.org/abs/1709.10218

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