Abstract
We prove the equivalence of various hyperbolic type properties for quasi-geodesics in CAT(0) spaces. Specifically, in our main theorem we prove that for \(X\) a CAT(0) space and \(\gamma \subset X\) a quasi-geodesic, the following four statements are equivalent: (1) \(\gamma \) is Morse, (2) \(\gamma \) is (b,c)—contracting, (3) \(\gamma \) is strongly contracting, and (4) in every asymptotic cone \(X_{\omega },\) any two distinct points in the ultralimit \(\gamma _{\omega }\) are separated by a cut-point. In particular, this characterization provides a converse to a generalized Morse stability lemma in the CAT(0) setting. In addition, under mild conditions we prove the equivalence of wideness and unconstrictedness in the CAT(0) setting.
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References
Algom-Kfir, Y.: Strongly contracting geodesics in outer space. Preprint arXiv:0812.155 (2010)
Behrstock, J.: Asymptotic geometry of the mapping class group and Teichmüller space. Geom. Topol. 10, 1523–1578 (2006)
Behrstock, J., Charney, R.: Divergence and quasimorphisms of right-angled Artin groups. Math. Ann. 1–18 (2011)
Behrstock, J., Drutu, C.: Divergence, thick groups, and short conjugators, Preprint 1110.5005 (2011)
Bestvina, M., Fujiwara, K.: A characterization of higher rank symmetric spaces via bounded cohomology. Geom. Funct. Anal. 19, 11–40 (2009)
Bridson, M., Haefliger, A.: Metric spaces of non-Positive curvature, Grad. Texts in Math. 319. Springer, New York (1999)
Brock, J., Farb, B.: Curvature and rank of Teichmüller space. Am. J. Math. 128, 1–22 (2006)
Brock, J., Masur, H.: Coarse and synthetic Weil-Petersson geometry: quasiats, geodesics, and relative hyperbolicity. Geom. Topol. 12, 2453–2495 (2008)
Brock, J., Masur, H., Minsky, Y.: Asymptotics of Weil-Petersson geodesics II: bounded geometry and unbounded entropy. Geom. Funct. Anal. 21, 820–850 (2011)
Charney, R.: Lecture entitled “Contracting boundaries of CAT(0) spaces”, at 3-manifolds, Artin Groups, and cubical geometry CBMS-NSF conference. CUNY, New York (2011)
Drutu, C., Mozes, S., Sapir, M.: Divergence in lattices in semisimple Lie groups and graphs of groups. Trans. Amer. Math. Soc. 362, 2451–2505 (2010)
Drutu, C., Sapir, M.: Tree-graded spaces and asymptotic cones of groups. Topology 44, 959–1058 (2005). With an appendix by Denis Osin and Mark Sapir
Kapovich, M., Leeb, B.: 3-Manifold groups and nonpositive curvature. Geom. Funct. Anal. 8, 841–852 (1998)
Masur, H., Minsky, Y.: Geometry of the complex of curves. I. Hyperbolicity. Invent. Math. 138, 103–149 (1999)
Morse, H.: A fundamental class of geodesics on any closed surface of genus greater than one. Trans. AMS 26, 25–60 (1924)
Mosher, L.: Stable Teichmüller quasigeodesics and ending laminations. Geom. Topol. 7, 33–90 (2003)
Osin, D.: Relatively hyperbolic groups: intrinsic geometry, algebraic properties, and algorithmic problems. Mem. Am. Math. Soc. 179(843), vi+100pp (2006)
Sultan, H.: The asymptotic cone of Teichmüller space: thickness and divergence. Ph.D. thesis, Columbia University (2012)
Acknowledgments
I want to express my gratitude to my advisors Jason Behrstock and Walter Neumann for their extremely helpful advice and insights throughout my research, and specifically regarding this paper. I would also like to acknowledge Igor Belegradek, Ruth Charney, and Amey Kaloti for useful conversations and insights regarding arguments and ideas in this paper.
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Sultan, H. Hyperbolic quasi-geodesics in CAT(0) spaces. Geom Dedicata 169, 209–224 (2014). https://doi.org/10.1007/s10711-013-9851-4
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DOI: https://doi.org/10.1007/s10711-013-9851-4