Nonaxiomatisability of Equivalences over Finite State Processes

Deciding Bisimulation-Like Equivalences with Finite-State Processes

We design a general method for proving decidability of bisimulationlike equivalences between infinite-state processes and finite-state ones. We apply this method to the class of PAD processes, which strictly subsumes PA and pushdown (PDA) processes, showing that a large class of bisimulation-like equivalences (including e.g. strong and weak bisimilarity) is decidable between PAD and finite-stat...

On the Complexity of Deciding Behavioural Equivalences and Preorders A Survey

This paper gives an overview of the computational complexity of all the equivalences in the linear/branching time hierarchy [vG90a] and the preorders in the corresponding hierarchy of preorders. We consider finite state or regular processes as well as infinite-state BPA [BK84b] processes. A distinction, which turns out to be important in the finite-state processes, is that of simulation-like eq...

On Finite Representations of Infinite-State Behaviours

We examine the problem of finite-state representability of infinitestate processes w.r.t. certain behavioural equivalences. We show that the classical notion of regularity becomes insufficient in case of all equivalences of van Glabbeek’s hierarchy except bisimilarity, and we design and justify a generalization in the form of strong regularity and finite characterizations. We show that the cond...

Deciding Bisimulation-Like Equivalences with Finite-State Processes

On the complexity of checking semantic equivalences between pushdown processes and finite-state processes

Simulation preorder/equivalence and bisimulation equivalence are the most commonly used equivalences in concurrency theory. Their standard definitions are often called strong simulation/bisimulation, while weak simulation/bisimulation abstracts from internal τ -actions. We study the computational complexity of checking these strong and weak semantic preorders/equivalences between pushdown proce...