Seminar 30 November 2006 - Laura Bozzelli
Speaker: Laura Bozzelli
Date: 30 November 2006
Time: 11am
Place: via Carloni 78, Sala Riunione
Title: Model checking problem for Process Rewrite Systems
Abstract:
We consider the model checking problem for Process Rewrite Systems (PRS), an infinite-state formalism (non Turing-powerful) which subsumes many common models such as Pushdown Processes, Petri Nets, and PA processes. PRS can be adopted as a formal model for programs with dynamic creation and (a restricted form of) synchronization of concurrent processes, and with recursive procedures.
We establish an exact decidability boundary of the model checking problem for PRS against properties described by basic fragments of action-based Linear Temporal Logic (LTL). It is known that the problem for general LTL properties is decidable for Petri nets and for pushdown processes, while it is undecidable for PA processes. As our main result, we show that the problem is decidable for PRS if we consider properties defined by formulae with only modalities "strict eventually" and "strict always". Moreover, we show that the problem remains undecidable for PA processes even with respect to the LTL fragment with the only modality "until" or the fragment with modalities "next" and "infinitely often".
Date: 30 November 2006
Time: 11am
Place: via Carloni 78, Sala Riunione
Title: Model checking problem for Process Rewrite Systems
Abstract:
We consider the model checking problem for Process Rewrite Systems (PRS), an infinite-state formalism (non Turing-powerful) which subsumes many common models such as Pushdown Processes, Petri Nets, and PA processes. PRS can be adopted as a formal model for programs with dynamic creation and (a restricted form of) synchronization of concurrent processes, and with recursive procedures.
We establish an exact decidability boundary of the model checking problem for PRS against properties described by basic fragments of action-based Linear Temporal Logic (LTL). It is known that the problem for general LTL properties is decidable for Petri nets and for pushdown processes, while it is undecidable for PA processes. As our main result, we show that the problem is decidable for PRS if we consider properties defined by formulae with only modalities "strict eventually" and "strict always". Moreover, we show that the problem remains undecidable for PA processes even with respect to the LTL fragment with the only modality "until" or the fragment with modalities "next" and "infinitely often".