Nicolas Markey

Résumé

Various extensions of the temporal logic ATL have recently been introduced to express rich properties of multi-agent systems. Among these, ATLsc extends ATL with strategy contexts, while Strategy Logic has first-order quantification over strategies. There is a price to pay for the rich expressiveness of these logics: model-checking is non-elementary, and satisfiability is undecidable.

We prove in this paper that satisfiability is decidable in several special cases. The most important one is when restricting to turn-based games. We prove that decidability also holds for concurrent games if the number of moves available to the agents is bounded. Finally, we prove that restricting strategy quantification to memoryless strategies brings back undecidability.

@inproceedings{gandalf2013-LM,
  author =              {Laroussinie, Fran{\c c}ois and Markey, Nicolas},
  title =               {Satisfiability of {ATL} with strategy contexts},
  editor =              {Puppis, Gabriele and Villa, Tiziano},
  booktitle =           {{P}roceedings of the 4th {I}nternational {S}ymposium
                         on {G}ames, {A}utomata, {L}ogics and {F}ormal
                         {V}erification ({GandALF}'13)},
  acronym =             {{GandALF}'13},
  series =              {Electronic Proceedings in Theoretical Computer
                         Science},
  volume =              {119},
  pages =               {208-223},
  year =                {2013},
  month =               aug,
  doi =                 {10.4204/EPTCS.119.18},
  abstract =            {Various extensions of the temporal logic ATL have
                         recently been introduced to express rich properties
                         of multi-agent systems. Among these, ATLsc extends
                         ATL with \emph{strategy contexts}, while Strategy
                         Logic has \emph{first-order quantification} over
                         strategies. There is a price to pay for the rich
                         expressiveness of these logics: model-checking is
                         non-elementary, and satisfiability is
                         undecidable.\par We prove in this paper that
                         satisfiability is decidable in several special
                         cases. The most important one is when restricting to
                         \emph{turn-based} games. We~prove that decidability
                         also holds for concurrent games if the number of
                         moves available to the agents is bounded. Finally,
                         we~prove that restricting strategy quantification to
                         memoryless strategies brings back undecidability.},
}