Annual Report 2010 - Fachgruppe Informatik an der RWTH Aachen ...

modern applications (like geographic data, constraint databases, data on the Web). Also in
verification, infinite (but finitely presentable) transition systems become more and more
important, in particular for applications to software.
We investigate several directions for making the methodology developed in finite model
theory applicable to infinite structures. Of particular importance are, again, the connections
between algorithmic issues and logical definability. We study algorithmic and definability
issues on various classes of infinite structures that are presentable by automata and logical
interpretations. The work by A. Blumensath, V. Bárány, and E. Grädel on automatic
structures has been very influential for the development of this field.
Algorithmic Synthesis of Reactive and Discrete-Continuous Systems (AlgoSyn)
E. Grädel, D. Fischer, Ł. Kaiser, B. Puchala, R. Rabinovich, M. Ummels
AlgoSyn is an interdisciplinary Research Training Group (Graduiertenkolleg) at RWTH
Aachen University lead by a group of ten professors representing five different disciplines.
Integrating approaches from computer and engineering sciences, the project aims at
developing methods for the automatised design of soft- and hardware. AlgoSyn is funded by
the German Science Foundation (DFG).
Inside this Graduiertenkolleg, our research group mainly focuses on foundational projects on
infinite games. In particular, we aim at extending game-based methodologies from two-player
games to multi-player games and to games that involve infinitary winning conditions.
Algorithmic Strategies in Multi-Player Games
E. Grädel, Ł. Kaiser
The goal of this project is to develop theoretical concepts and algorithmic methods for the
analysis of interactive non-terminating systems. The focus is on state-based systems which
can be modelled as multi-player games on graphs. Traditionally, research in this area has
concentrated on situations of conflict between two agents (e.g., system and environment)
yielding a rich and effective theory for two-player zero-sum games of infinite durations. Our
objective is to extend this theory to incorporate the potential of cooperation which arises when
two or more agents interact in situations that are not necessarily conflicting.
For interactive behaviour over a finite duration of time, the corresponding model of non-zerosum
games is well established in classical Game Theory. To cope with non-terminating
behaviour, however, we need to extend fundamental solution concepts and make them
accessible to algorithmic treatment. Aside with games of perfect information, we investigate
games of imperfect information with different sources of uncertainty. One particular task is to
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