Retreat 2019 of the SFB-TRR 195

The retreat at half-time of the SFB-TRR 195 with a view to the future takes place from Monday, 18th  February to Thursday, 21st February, in the Ebernburg in Bad Münster am Stein. The organisors are Hannah Markwig, Gunter Malle and Michael Kunte.


The main intention is to strengthen cooperation within SFB-TRR 195. Therefore, there will only be very few plenary lectures, instead all mathematical and all software focuses should be given enough opportunity to retreat and work together. In addition, there will be overview lectures for each mathematical focus and also from the OSCAR project, which generally explain how the status of the respective subprojects and their embedding in the overall objective is.

The second focus of the retreat will be the strategic development of the SFB-TRR 195. The aim of the retreat is the preparation of a first list of preliminary projects of the second funding period.

In addition, the second meeting of the IRTG seminar of the PhD-students in the SFB-TRR 195 will be held during the retreat.


Group and representation theorysurvey talk / presentationGunter Malle
Algebraic geometry, commutative and non-commutative algebrasurvey talk / presentationFrank-Olaf Schreyer
Tropical and polyhedral geometrysurvey talk / presentationHannah Markwig
Free probability and random matricessurvey talk / presentationRoland Speicher
Number theorysurvey talk / presentationGabriele Nebe
Computational developments / OSCARsurvey talk / presentationWolfram Decker
Finite simple groups and their representationsplenary lectureGerhard Hiß
Chevalley’s Theorem on constructible images made constructiveplenary lectureMohamed Barakat

Abstracts of the talks:

Gerhard’s talk: This talk is intended as a survey, addressing non-specialists, on finite simple groups. After introducing some of them, I will focus on the fundamental questions concerning their subgroups and linear representations. Using specific examples, I will comment on the state of art with respect to these questions.

Mohamed’s talk: Chevalley proved that the image of an algebraic morphism between algebraic varieties is a constructible set. Examples are orbits of algebraic group actions. A constructible set in a topological space is a finite union of locally closed sets and a locally closed set is the difference of two closed subsets. Simple examples show that even if the source and target of the morphism are affine varieties the image may neither be affine nor quasi-affine. In this talk I will present an Gröbner-basis-based algorithm which computes the constructible image of a morphism of affine spaces.


TimeMonday 18th FebTuesday 19th FebWednesday 20th FebThursday 21st Feb
9:00-10:30Group work: Five Core areasGroup work9:00-9:30: Group work,
9:30-10:30: Presentations new projects of the SFB-TRR 195
10:30-11:00Coffee breakCoffee breakCoffee break
11:00-12:30Group work: E.g. OSCARGroup workPresentations new projects of the SFB-TRR 195
13:30-15:304x25 min PresentationsGroup work / IRTG-SeminarGroup workSteering Committee Meeting
15:30-16:00Coffee breakCoffee breakCoffee breakCoffee break
16:00-17:002x25 min Presentationsplenary lectureplenary lecture
17:00-17:30Planning the group workPlanning the group workPlanning the group work
19:00Wine tastingSteering Committee Meeting

We start at Monday, 18th Feb, at 13:30, with the presentations at the Martin-Luther-Saal. For non-members of the Steering Committee the retreat ends after lunch on Thursday, 21st.

Confirmed Participants

Ali Aslam
Mohamed Barakat
Reimer Behrends
Janko Böhm
Bernhard Böhmler
Simon Brandhorst
Thomas Breuer
Wolfram Decker
Claus Fieker
Johannes Flake
Ghislain Fourier
Anne Frühbis-Krüger
Andreas Gathmann
Meinolf Geck
Daniel Gromada
Sebastian Gutsche
William Hart
Jonas Hetz
Gerhard Hiß
Johannes Hoffmann
Tommy Hofmann
Max Horn
Michael Joswig
Stefan Jung
Lars Kastner
Yeongrak Kim
Markus Kirschmer
Matthias Klupsch
Michael Kunte
Caroline Lassueur
Vladimir Lazic
Viktor Levandovskyy
Frank Lübeck
Laura Maaßen
Gunter Malle
Suri Mannaperuma
Magdaleen Marais
Hannah Markwig
Gabriele Nebe
Alice Niemeyer
Alessandro Paolini
Miguel Pluma
Sebastian Posur
Emil Rotilio
Simon Schmidt
Hans Schönemann
Frank-Olaf Schreyer
Pascal Schweitzer
Carlo Sircana
Roland Speicher
Andreas Steenpass
Christian Steinhart
Isabel Stenger
Andrea Thevis
Ulrich Thiel
Ayush Kumar Tewari
Sascha Timme
Yvonne Weber
Moritz Weber
Gabriela Weitze-Schmithüsen
Sheng Yin
Eva Zerz



Since the presence of all PIs is essential, a room will be reserved for each PI. We ask postdocs, doctoral students and others to register with Michael Kunte or Barbara Ermisch via email until November 30th, 2018.


The Ebernburg in Bad Münster am Stein can be easily reached by train (train station “Bad Münster am Stein”) or car from all main locations.

If the weather is good, we also organize a group trip by bicycle from Kaiserslautern.