We study charging effects and tunneling in the single electron box. Tunneling mixes different charge states and in the nonperturbative regime the charge in the island may be strongly screened. When charge states are nearly degenerate the screening of the charge is strong even in the weak tunneling regime. Virtual tunneling processes reduce both the level splitting ∆ and the tunneling strength α...

Tunneling is probably the most important physical process. The observation that particles surmount a high mountain in spite of the fact that they don’t have the necessary energy can not be explained by classical physics. However, this so called tunneling became allowed by the theory of quantum mechanics. Experimental tunneling studies with different photonic barriers from microwave frequencies ...

Ben-Amram and Codish described SCNP [2], a subclass of the size-change termination criterion SCT [8], which permits efficient certificate checking. Termination problems in this class have a global ranking function of a certain form, which can be found using SAT solving. This note describes an automated proof reconstruction for this certificate scheme, implemented in the theorem prover Isabelle/...

It is widely believed that in principle it’s possible to reduce most of present-day mathematics to reasoning in a formal logical system. The technical difficulty of actually doing so is quite formidable. However, the arrival of the computer is changing this situation, since computers are good at helping with such tedious symbolic manipulation. The computer formalization of mathematics is now a ...

We suggest that mechanized multi-agent deontic logics might be appropriate vehicles for engineering trustworthy robots. Mechanically checked proofs in such logics can serve to establish the permissibility (or obligatoriness) of agent actions, and such proofs, when translated into English, can also explain the rationale behind those actions. We use the logical framework Athena to encode a natura...

A novel protocol has been formally analyzed using the prover Isabelle/HOL, following the inductive approach described in earlier work [10]. There is no limit on the length of a run, the nesting of messages or the number of agents involved. A single run of the protocol delivers session keys for all the agents, allowing neighbours to perform mutual authentication. The basic security theorem state...

As airspace becomes ever more crowded, air traffic management must reduce both space and time between aircraft to increase throughput, and on-board collision avoidance systems become ever more important. These systems and the policies that they implement must be extremely reliable. In this paper we consider implementations of distributed collision avoidance policies designed to work in environm...

We present an expressive information-flow control type system with recursive types, existential label polymorphism, and impredicative polymorphism for a higher-order programming language state. give novel semantic model of this show that well-typed programs satisfy termination-insensitive noninterference. Our approach supports compositional integration syntactically ill-typed---but semantically...