A generalized approach to particle interaction can confer advantages over previously described method in terms of one or more of communications bandwidth and latency and memory access characteristics. These generalizations can involve one or more of at least spatial decomposition, import region rounding, and multiple zone communication scheduling. An architecture for computation of particle interactions makes use various forms of parallelism. In one implementation, the parallelism involves using multiple computation nodes arranged according to a geometric partitioning of a simulation volume.