Higher-Order Dynamics in Event Structures

Event Structures (ESs) address the representation of direct relationships between individual events, usually capturing the notions of causality and conflict. Recently, Arbach et al. introduced the new Dynamic Causality Event Structure (DCES), in which some event may change the causal dependencies of other events, by adding or dropping causal predecessors. Interestingly, DCES turned out to be incomparable-concerning their expressive power-to van Glabbeek's and Plotkin's Event Structure for Resolvable Conflicts (RCES), up to then considered to be one of the most general ES models. In this paper, also motivated by process modelling in the health care domain, we present a generalisation of the DCESs, by firstly allowing sets of events for modifying dependencies, and secondly by introducing higher-order dynamics. We show that the newly defined structure is strictly more expressive than the RCESs.