Felix Mann

Assistant and PhD Student

T: +41 26 300 8431

Address: Bd de Pérolles 90, 1700 Fribourg

Office: C 304



Short bio

I obtained both my Bachelor and Master degree of Mathematics at the Freie Universität Berlin in 2017 and 2019, respectively. At the University of Fribourg I pursue a PhD under the supervision of Prof. Bernard Ries.


My research interests:

  • Algorithmic and Structural Graph theory
  • Complexity theory


What my PhD Thesis is about

My current research is focusing on so-called blocker problems. This rich family of problems is concerned with determining or estimating how often we have to apply a certain graph operation (such as deleting vertices or adding, deleting and contracting edges, etc.) in order to reduce some graph parameter. My publications  have so far mostly been concerned with reducing several different domination parameters (such as the ((semi-)total) domination number) by deleting vertices and/or contracting edges. We have succesfully established complexity dichotomies for several of these problems, that is, for a large family of graph classes we could determine the computational complexity  for each member of that family. In the future, we are trying to expand not only the parameters and operations which are considered but also the methods and approaches used to obtain optimization algorithms and structural results.


PhD advisor: Prof. Bernard Ries


Teaching activities




  • Blocking total dominating sets via edge contractions, E. Galby, F. Mann, B. Ries, Theoretical Computer Science 877 18-35 (available through  Open Access)
  • Reducing the domination number of $P_3+kP_2$-free graphs via one edge contraction, E. Galby, F. Mann, B. Ries, Discrete Applied Mathematics 305 205-210 (available through Open Access)
  • Using edge contractions to reduce the semitotal domination number, E. Galby, F. Mann, P.T. Lima, B. Ries, Theoretical Computer Science 939 (2023) 140 - 160 Open Access 
  • Using Edge Contractions and Vertex Deletions to Reduce the Independence Number and the Clique Number, F. Lucke, F. Mann, IWOCA 2022, LNCS 13270, 412-424, 2022 (preprint available on arxiv)
  • Reducing Graph Parameters by Contractions and Deletions, F. Lucke, F. Mann, to appear in Algorithmica  Open Access