This paper studies the existence of finite equational axiomatisations of the interleaving parallel composition operator modulo the behavioural equivalences in van Glabbeek's linear time-branching time spectrum. In the setting of the process algebra BCCSP over a finite set of actions, we provide finite, ground-complete axiomatisations for various simulation and (decorated) trace semantics. We also show that no congruence over BCCSP that includes bisimilarity and is included in possible futures equivalence has a finite, ground-complete axiomatisation; this negative result applies to all the nested trace and nested simulation semantics.

@article{paperbot1740,
  title = {On the Axiomatisability of Parallel Composition},
  author = {Luca Aceto and Valentina Castiglioni and Anna Ingolfsdottir and Bas Luttik and Mathias R. Pedersen},
  journal = {Logical Methods in Computer Science},
  volume = {Volume 18, Issue 1},
  year = {2022},
  doi = {10.46298/lmcs-18(1:15)2022}
}