From Hierarchical to Relative Hyperbolicity. (13th July 2020)

• Record Type: Journal Article
• Authors: Russell, Jacob
• Is Part Of: International mathematics research notices. Volume 2022:Number 1(2022)
• Page Start: 575
• Page End: 624
• Publication Date: 2020-07-13
• Subjects: Mathematics -- Periodicals; 510
• DOI: 10.1093/imrn/rnaa141
• Languages: English
• ISSNs: 1073-7928

Abstract

Abstract: We provide a simple, combinatorial criteria for a hierarchically hyperbolic space to be relatively hyperbolic by proving a new formulation of relative hyperbolicity in terms of hierarchy structures. In the case of clean hierarchically hyperbolic groups, this criteria characterizes relative hyperbolicity. We apply our criteria to graphs associated to surfaces and prove that the separating curve graph of a surface is relatively hyperbolic when the surface has zero or two punctures. We also recover a celebrated theorem of Brock and Masur on the relative hyperbolicity of the Weil–Petersson metric on Teichmüller space for surfaces with complexity three.