Split and ST Bisimulation Semantics

Abstract

AbstractIn this paper the notion of action atomicity is relaxed by permitting actions to be observed in the middle of their evolution. Non-atomic semantic equivalences, based on the notion of bisimulation, are studied over stable event structures, Splitn bisimulation equivalence (denoted ∼n considers each event as composed of n phases. ST bisimulation equivalence (denoted ∼ST) is a slight refinement of ∼2 where each ending phase is unambiguously associated to a beginning phase, We prove that, by increasing n, we get finer and finer equivalences (i.e., ∼n + 1 ⊆ ∼n) and, moreover, that ∼n + 1 coincides with ∼ST over those event structures whose autoconcurrency is at most n. The main consequence of these results is that, for image finite event structures, ∼ST is the intersection of all the ∼n