# CAT(-1)-spaces, divergence groups and their commensurators

@article{Burger1996CAT1spacesDG, title={CAT(-1)-spaces, divergence groups and their commensurators}, author={M. Burger and Shahar Mozes}, journal={Journal of the American Mathematical Society}, year={1996}, volume={9}, pages={57-93} }

A CAT(−1)-space is a metric geodesic space in which every geodesic triangle is thinner than its associated comparison triangle in the hyperbolic plane ([B], [BriHa], [Gr]). The CAT(−1)-property is one among many possible generalizations to singular spaces of the notion of negative curvature. Important examples of CAT(−1)-spaces include Riemannian manifolds of sectional curvature k ≤ −1 and their convex subsets ([B-G-S]), metric trees and piecewise hyperbolic cell complexes ([Mou],[Da],[Hag],[Be… Expand

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