Date Added: Aug 2009
Stutter-invariant specifications do not distinguish between system behaviors that differ from each other only by the number of consecutive repetitions of the observed system states. Stutter invariance is crucial for refining specifications and for modular reasoning. Apart from these conceptual reasons for restricting oneself to stutter-invariant specifications, there is also a more practical motivation: stuttering invariance is an essential requirement for using partial-order reduction techniques infinite-state model checking. Unfortunately, checking whether an LTL formula or an automaton describes a stutter-invariant property is PSPACE-complete.