Heriot-Watt algebra online seminar, April 2020
Algebra and Geometry Seminar, Bristol, March 2020
Junior Geometry Seminar (BRIJGES), Bristol, March 2020
Group theory days in Düsseldorf, Düsseldorf, January 2020
Max Dehn Seminar, Salt Lake City, October 2019
Mini Max Dehn Seminar, Salt Lake City, October 2019
Southampton-Bielefeld Geometric Group Theory Meeting, Southampton, September 2019
Algebra/Topology Seminar, Copenhagen, September, 2019
Oberseminar Modelltheorie, Geometrie und Gruppentheorie, Münster, June 2019
AG-Seminar Topologie, Karlsruhe, June 2019
Oberseminar Algebra und Geometrie, Magdeburg, April 2019
SPP 2026 - Geometry at infinity conference, Münster, April 2019; Slides of this talk
"Reflections and harmonies: Coxeter groups in music theory" - SYMBol, Bielefeld, February 2019
Bielefeld-Münster Seminar on Groups, Geometry and Topology, January 2019
Junior Topology and Group Theory Seminar, Oxford, October 2018
"Higher connectivity of free factor complexes" - Poster presented at Geometric Group Theory in Campinas, July 2018
Junior Geometry and Topology Seminar (GATEWAY), Warwick, April 2018
BKMR Research Seminar on Geometric Group Theory, Münster, August 2017
Bielefeld-Münster Seminar on Groups, Geometry and Topology, Bielefeld, July 2017
Oberseminar Gruppen und Geometrie, Bielefeld, June 2016
Oberseminar Modelltheorie, Geometrie und Gruppentheorie, Münster, May 2016
Models and Groups 6, Istanbul, March 2016
In October and November 2019, I visited Mladen Bestvina at the University of Utah.
In October and November 2018, I visited Ric Wade at the University of Oxford.
In Bielefeld, I was organising a weekly meeting on geometric group theory: Friday GGT.
I was one of the organisers of the conference Outer Space in Bielefeld which took place in Bielefeld from 24th to 26th of September 2019.
I was one of the organisers of the block seminar Arithmetic groups and Rigidity which took place in Bielefeld from 21st to 23rd of March 2018. A shortened pdf-version of the introduction I gave at this seminar can be found here.
The following link leads to a petition asking to free Tuna Altınel, who was arrested in Turkey: Free Tuna Altınel. Further information can be found here.
I am a member of the DFG priority programm "Geometry at infinity": SPP 2026.