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arXiv · 1510.05393

Asymptotic rank of spaces with bicombings

Dominic Descombes
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Abstract

The question, under what geometric assumptions on a space X an n-quasiflat in X implies the existence of an n-flat therein, has been investigated for a long time. It was settled in the affirmative for Busemann spaces by Kleiner, and for manifolds of non-positive curvature it dates back to Anderson and Schroeder. We generalize the theorem of Kleiner to spaces with bicombings. This structure is a weak notion of non-positive curvature, not requiring the space to be uniquely geodesic. Beside a metric differentiation argument, we employ an elegant barycenter construction due to Es-Sahib and Heinich by means of which we define a Riemannian integral serving us in a sort of convolution operation.

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Dominic Descombes. 2015-10-19. Asymptotic rank of spaces with bicombings. https://arxiv.org/abs/1510.05393

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