Groups Acting on CAT (0) Square Complexes
نویسنده
چکیده
We study groups acting on CAT (0) square complexes. In particular we show if Y is a nonpositively curved (in the sense of A. D. Alexandrov) finite square complex and the vertex links of Y contain no simple loop consisting of five edges, then any subgroup of π1(Y ) either is virtually free abelian or contains a free group of rank two. In addition we discuss when a group generated by two hyperbolic isometries contains a free group of rank two and when two points in the ideal boundary of a CAT (0) 2-complex at Tits distance π apart are the endpoints of a geodesic in the 2-complex. Mathematics Subject Classification(2000). 57M20, 20F67, 20E07.
منابع مشابه
Groups acting on CAT(0) cube complexes
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