Structure of concurrency
A new approach to the semantic of concurrency is proposed. It is motivated by the remark that the causal order of events is sometimes insufficient to describe adequately some aspect of concurrent behaviour, this happens for example in the case of systems with priority and for Petri nets with inhibitor arcs. Three levels of description are distinguished. At the bottom level -- called observation level -- the system is represented by partial orders with the ordering giving precedence of events and incomparability denoting simultaneity. Relations between observations and interval orders are thoroughly examined. The next level discussed is the invariant level. Roughly, invariants are relations that are universally satisfied over the set of observations of a system. Further developments of the theory lead to the notions of histories and paradigms, where paradigms are intended to capture structural properties of histories.
scientific article; zbMATH DE number 417333
scientific article