Seminar on Foundations of Computing

This research seminar provides a venue for presenting research results concerning algorithm design, discrete mathematics, formal methods, logic and related areas of theoretical computer science. The seminar is jointly organized by the research laboratories DIMEA, FORMELA, and LIVE. The seminar builds on the FMDSA seminar organized by the FORMELA laboratory in the past.

Time and place

The seminar takes place on Monday at 2PM term time in Room C417 in the building of the Faculty of Informatics on a (roughly) weekly schedule.

Spring 2024 – schedule overview

February 19Liana Khazaliya (TU Vienna)Upward and Orthogonal Planarity are W[1]-hard Parameterized by Treewidth
March 4Martin Dzúrik (Masaryk University)Combinatorial Spectra of Graphs

Upcoming speakers

April 3Mickael Randour (University of Mons)
April 15Samuel Braunfeld (Charles University)
April 22Niklas Schlomberg (University of Bonn)
May 6Kaushik Mallik (ISTA)
June 3Alexandru Malekshahian (King's College London)
June 10Felix Schröder (Charles University)

Liana Khazaliya (TU Vienna): Upward and Orthogonal Planarity are W[1]-hard Parameterized by Treewidth

Monday, February 19, 14:00, room C417

Upward Planarity Testing and Orthogonal Planarity Testing are central problems in graph drawing. It is known that they are both NP-complete, but XP when parameterized by treewidth [Orthogonal: GD'19; Upward: SoCG'22]. In this talk, I will show that these two problems are W[1]-hard parameterized by treewidth, which answers open problems posed in two earlier papers. The key step in our proof is an analysis of the All-or-Nothing Flow problem, a generalization of which was used as an intermediate step in the NP-completeness proof for both planarity testing problems. We prove that the flow problem is W[1]-hard parameterized by treewidth on planar graphs, and that the existing chain of reductions to the planarity testing problems can be adapted without blowing up the treewidth. Our reductions also show that the known n^{O(tw)}-time algorithms cannot be improved to run in time n^{o(tw)} unless the Exponential Time Hypothesis fails.

Joint work with Bart M. P. Jansen, Philipp Kindermann, Giuseppe Liotta, Fabrizio Montecchiani, and Kirill Simonov



Martin Dzúrik (Masaryk University): Combinatorial Spectra of Graphs

Monday, March 4, 14:00, room C417

Combinatorial spectra of graphs is a generalization of H-Hamiltonian spectra. The main motivation was to made from H-Hamiltonian spectra an operation and develop some algebra in this field. An improved version of this operation form a commutative monoid. The most important thing is that most of the basic concepts of graph theory, such as maximum pairing, vertex and edge connectivity and coloring, Ramsey numbers, isomorphisms and regularity, can be expressed in the language of this operation.

Arxiv preprint avalilable here




Past terms

Fall 2023

Spring 2023

Fall 2022

Spring 2022

Fall 2021

Spring 2021: Special Seminarpart of Round the World Relay in Combinatorics, where a number of seminars and groups around the world were getting together. Each site hosted a talk, and everyone was welcome.

Fall 2020: ITI Online Seminara one-semester online venue for presenting current research in discrete mathematics and theoretical computer science in the Czech Republic.

Spring 2020

Fall 2019

Spring 2019