SMS scnews item created by James Morgan at Mon 24 Feb 2025 1227
Type: Seminar
Distribution: World
Expiry: 7 Apr 2025
Calendar1: 3 Mar 2025 1400-1500
CalLoc1: SMRI Seminar Room (A12 Room 301)
Auth: [email protected] (jmor4790) in SMS-SAML

Geometry and Topology Seminar

On canonical ideal cell decompositions of decorated hyperbolic surfaces

Ivan Telpukhovskiy (Tsinghua)

Please join us for the next installment of the Geometry and Topology Seminar for 2025!

Location

SMRI Seminar Room (A12 Room 301)

Abstract

We give another proof of the following result: the Epstein-Penner ideal cell decomposition of a decorated hyperbolic surface with punctures matches the Bowditch-Epstein ideal cell decomposition. Further, we introduce a generalized notion of the cut locus (also known as spine or collision locus) for decorated crowned hyperbolic surfaces, and show that we naturally get two distinct decompositions of decorated Teichmüller space of surfaces with crowns. Both of them are ideal cell decompositions (this recovers some results of Penner). Finally, we discuss a third decomposition in the setting of decorated ideal hyperbolic polygons.