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arXiv · 1806.07074

Cohomology and the Bowditch Boundary

Abstract

We give a group cohomological description of the \v{C}ech cohomology of the Bowditch boundary of a relatively hyperbolic group pair, generalizing a result of Bestvina-Mess about hyperbolic groups. In case of a relatively hyperbolic Poincar\'e duality group pair, we show the Bowditch boundary is a homology manifold. For a three-dimensional Poincar\'e duality pair, we recover the theorem of Tshishiku-Walsh stating that the boundary is homeomorphic to a two-sphere.

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Jason Fox Manning, Oliver Wang. 2018-06-19. Cohomology and the Bowditch Boundary. https://arxiv.org/abs/1806.07074

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