# Bonn Topology Group - Abstracts

General Information - Members - Activities - Topology Seminar

### Talk

April 16th 2019

Giles Gardam (WWU Münster):
Boundaries of hyperbolic and CAT(0) groups and Cannon-Thurston maps.

### Abstract

A fundamental invariant in the study of hyperbolic groups is their boundaries.
The classical Cannon-Thurston map for a closed fibered hyperbolic 3-manifolds relates two such boundaries: It gives a continuous surjection from the boundary of the surface group
(a circle) to the boundary of the 3-manifold group (a 2-sphere). Mitra generalized this to all hyperbolic groups with hyperbolic normal subgroups.
I will explain why such a generalization to CAT(0) groups with the visual boundary is impossible.

Joint work with Beeker-Cordes-Gupta-Stark.

Back to seminar page

## News

Lucas Mann recevices the Hausdorff memorial award 2021/22

Bachelor Prize 2021/22 of the BMG awarded

Prof. Daniel Huybrechts receives the Compositio Prize for the periode 2017-2019

Prof. Catharina Stroppel receives Gottfried Wilhelm Leibniz Prize 2023

Rajula Srivastava receives Association for Women in Mathematics Dissertation Prize

Prof. Ana Caraiani wins a New Horizons in Mathematics Prizes 2023

Pius XI Medal awarded to Professor Peter Scholze

Prof. Dr. Ana Caraiani neuer Hausdorff Chair am Mathematischen Institut

Prof. Valentin Blomer und Prof. Georg Oberdieck erhalten ERC grants

Bonn Mathematics ranked 15th in Shanghai Ranking

Grants for Mathematics students from Ukraine

Corona: Measures at the Center for Mathematics

Prof. Jessica Fintzen is awarded a Whitehead Prize of the London Mathematical Society

Prof. Peter Scholze elected as Foreign Member of the Royal Society

Bonner Mathematik belegt bei Shanghai Ranking den 1. Platz in Deutschland und weltweit den 13. Platz

Prof. Daniel Huybrechts erhält gemeinsam mit Debarre, Macri und Voisin ERC Synergy Grant