Orateur(s)  Ara Basmajian  NewYork,

Titre  Arcs, orthogeodesics, and hyperbolic surface identities 
Date  09/06/2015 
Horaire  14:00 à 15:00 

Diffusion  
Résume  Let X be a compact hyperbolic surface with either geodesic or horocyclic boundary. The homotopy class (rel the boundary) of a nontrivial arc from the boundary to itself can be realized by an orthogeodesic  a geodesic segment perpendicular to the boundary at its initial and terminal points. This talk is about a special subclass of orthogeodesics called primitive orthogeodesics. In work with Hugo Parlier and Ser Peow Tan we show that the primitive orthogeodesics arise naturally in the study of maximal immersed pairs of pants in X and are intimately connected to regions of X in the complement of the natural collars. These considerations lead to continuous families of new identities  equations that remain constant on the space of hyperbolic structures. 
Salle  15–25.502 
Adresse  Jussieu 