Recent analysis of classical algorithms resulted in their axiomatization as transition systems satisfying simple postulates, and in the Abstract State Machine Theorem, stating that any such transition system can be programmed in a most general model of computation, called “abstract state machines”. In this way, classical abstract state machines answer the question “What is an algorithm?” for th...

The inherent properties of specific physical systems can be used as metaphors for investigation of the behavior of complex networks. This insight has already been put into practice in previous work, e.g., studying the network evolution in terms of phase transitions of quantum gases or representing distances among nodes as if they were particle energies. This paper shows that the emergence of di...

The hierarchy of Symbolic Transition Systems, introduced by Henzinger, Majumdar and Raskin, is an elegant classification tool for some families of infinite-state operational models that support some variants of a symbolic “backward closure” verification algorithm. It was first used and illustrated with families of hybrid systems. In this paper we investigate whether the STS hierarchy can accoun...