Pierre Ohlmann

My current research involves structural and algorithmic aspects of infinite duration games, as well as different problems related to logics on graphs. In the past, I have also worked on verification, arithmetic circuits, stochastic control, and a bit of AI.

Thesis

• Monotonic graphs for parity and mean-payoff games, defended December 13th, slides

Journals

• Characterizing positionality in games of infinite duration over infinite graphs, Single author, TheoretiCS, 2023
• Controlling a random population, With Nathanaël Fijalkow and Thomas Colcombet, Logical Methods in Computer Science, 2022
• The theory of universal graphs for infinite duration games, With Nathanaël Fijalkow and Thomas Colcombet, Logical Methods in Computer Science, 2021
• Lower bounds for arithmetic circuits via the Hankel matrix, With Nathanaël Fijalkow, Guillaume Lagarde and Olivier Serre, Computational Complexity, 2021
• Semialgebraic invariant synthesis for the Kannan-Lipton orbit problem, With Nathanaël Fijalkow, Joël Ouaknine, Amaury Pouly and James Worrell, Theory of Computing Systems, 2019

Conferences

• Rank-decreasing transductions, With Mikołaj Bojanczyk, LICS, 2024
• Positional omega-regural languages, With Antonio Casares, LICS, 2024
• Positionality in Sigma2 and a completeness result, With Michał Skrzypczak, STACS, 2024
• Flipper games for monadically stable graph classes, With J. Gajarský, N. Mählmann, R. McCarty, Mi. Pilipczuk, W. Przybyszewski, S. Siebertz, M. Sokołowski and S. Toruńczyk, ICALP, 2023
• Canonical decompositions in monadically stable and bounded shrubdepth graph classes, With Michał Pilipczuk, Wojchiech Przybychewski and Szymon Toruńczyk, ICALP, 2023
• Characterising memory in infinite games, With Antonio Casares, ICALP, 2023
• A technique to speed up symmetric attractor-based algorithms for parity games, With Marcin Jurdziński and K. S. Thejaswini, FSTTCS, 2022
• Characterizing positionality in games of infinite duration over infinite graphs, Single author, LICS, 2022
• The GKK Algorithm is the Fastest over Simple Mean-Payoff Games, Single author, CSR, 2022
• Scaling Neural Program Synthesis with Distribution-based Search, With Nathanaël Fijalkow, Guillaume Lagarde, Théo Matricon, Kevin Ellis and Akarsh Potta, AAAI, 2022
• New Algorithms for Combinations of Objectives using Separating Automata, With Ashwani Anand, Nathanaël Fijalkow, Aliénor Goubault-Larrecq and Jérôme Leroux, Gandalf, 2021
• The complexity of mean payoff games using universal graphs, With Nathanaël Fijalkow and Paweł Gawrychowski, MFCS, 2020
• Lower bounds for arithmetic circuits via the Hankel matrix, With Nathanaël Fijalkow, Guillaume Lagarde and Olivier Serre, STACS, 2022
• Controlling a Random Population, With Nathanaël Fijalkow and Thomas Colcombet, FoSSaCS, 2020
• On the Monniaux Problem in Abstract Interpretation, With N. Fijalkow, E. Lefaucheux, J. Ouaknine, A. Pouly and J. Worrell, SAS, 2019
• Semialgebraic Invariant Synthesis for the Kannan-Lipton Orbit Problem, With Nathanaël Fijalkow, Joël Ouaknine, Amaury Pouly and James Worrell, STACS, 2017

Preprints

• Fast value iteration for energy games, With Antonio Casares, arxiv, 2021

Some recent sets of slides

• Transformations logiques de graphes (JSL)
• Rank-decreasing transductions
• Positionality of omega-regular objectives
• FO model-checking on graphs
• Positionality in Sigma2
• Games of infinite duration memory
• The GKK algorithm is fastest over simple mean-payoff games " (short version)"
• Positionality via monotonic graphs " (short version)"
• Solving energy games by hand
• Monotonic graphs for positional games (short version)
• Controlling a random population
• Arithmetic circuit lower bounds via the Hankel matrix
• Solving mean payoff games with universal graphs