Tight geodesics in the curve complex

• 成果类型: Article
• 署名作者: Bowditch, Brian H.
• 署名单位: University of Southampton
• 刊物名称: INVENTIONES MATHEMATICAE
• ISSN/ISSBN: 0020-9910
• DOI: 10.1007/s00222-007-0081-y
• 发表日期: 2008
• 页码: 281-300
• 关键词: SUBGROUPS; geometry

摘要

The curve graph, g, associated to a compact surface Sigma is the 1-skeleton of the curve complex defined by Harvey. Masur and Minsky showed that this graph is hyperbolic and defined the notion of a tight geodesic therein. We prove some finiteness results for such geodesics. For example, we show that a slice of the union of tight geodesics between any pair of points has cardinality bounded purely in terms of the topological type of Sigma. We deduce some consequences for the action of the mapping class group on g. In particular, we show that it satisfies an acylindricity condition, and that the stable lengths of pseudoanosov elements are rational with bounded denominator.