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arXiv · 2206.03558

Finite conjugacy classes and split exact cochain complexes

Christian Rosendal
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Abstract

We study the cohomology of isometric group actions on (super) reflexive Banach spaces with a focus on the relation between finite conjugacy classes and split exactness of cochain complexes. In particular, we show that, if a uniformly convex Banach module has no almost invariant vectors under the FC-centre of the acting group, then the associated cochain complex is split exact. Other similar rigidity results are established that are related to prior work of Bader - Furman - Gelander - Monod, Bader - Rosendal - Sauer and Nowak.

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Christian Rosendal. 2022-06-07. Finite conjugacy classes and split exact cochain complexes. https://arxiv.org/abs/2206.03558

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