The non-determinism, complexity, and size of distributed software systems present significant difficulties for designers and maintainers. Visualization can help alleviate these difficulties through interactive exploratory tools that allow both novice and experienced users to investigate a distributed computation using a common tool set. Essential to the success of a visual exploration tool is t...

We propose a general framework for first-order functional logic programming, supporting lazy functions, non-determinism and polymorphic datatypes whose data constructors obey a set C of equational axioms. On top of a given C, we specify a program as a set R of Cbased conditional rewriting rules for defined functions. We argue that equational logic does not supply the proper semantics for such p...

The quantum model of computation not only o ers entirely new ways to manipulate information, but also allows information processing tasks to be formulated in unconventional, genuine quantum mechanical terms. We show that the task of distinguishing among entangled quantum states combines entanglement and non-determinism in a way that makes the quantum solution impossible to simulate on any class...

Monads have been recognized by Moggi as an elegant device for dealing with stateful computation in functional programming languages. It is thus natural to develop a Hoare calculus for reasoning about computational monads. While this has previously been done only for the state monad, we here provide a generic, monad-independent approach, which applies also to further computational monads such as...

Watson–Crick automata are finite state automata working on double-stranded tapes, introduced to investigate the potential of DNA molecules for computing. In this paper, we continue the investigation of descriptional complexity ofWatson–Crick automata initiated by Păun et al. [A. Păun, M. Păun, State and transition complexity of Watson–Crick finite automata, in: G. Ciobanu, G. Paun (Eds.), Funda...

Several formalisms for concurrent computation have been proposed in recent years that incorporate means to express stochastic continuous-time dynamics and non-determinism. In this setting, some obscure phenomena are known to exist, related to the fact that schedulers may yield too pessimistic verification results, since current nondeterminism can surprisingly be resolved based on prophesying th...

Zielonka’s theorem, established 25 years ago, states that any regular language closed under commutation is the language of an asynchronous automaton (a tuple of automata, one per process, exchanging information when performing common actions). Since then, constructing asynchronous automata has been simplified and improved [6, 20, 7, 12, 8, 4, 2, 21, 22]. We first survey these constructions and ...

We present a scheme for non-deterministically approximating photon number resolving detectors using non-discriminating detectors. The model is simple in construction and employs very few physical resources. Despite its non-determinism, the proposal may nonetheless be suitable for use in some quantum optics experiments in which non-determinism can be tolerated. We analyze the detection scheme in...