No abstract

No abstract

No abstract

We discuss the existence of the electromagnetic Stark ladder in some optic systems by studying the propagation of light. The transmission coefficient is calculated by means of the transfer-matrix method. It is shown that although the transfer matrix is different from the quantum case it can give, in some particular configurations, a Stark-ladder resonance structure similar to the one observed in quantum systems. The relation between these resonances and a Fabry-Perot-like interference is discussed. Consideration is given to the observability of these ladders in the laboratory.

In the compromise model of continuous opinions proposed by Deffuant et al, the states of two agents in a network can start to converge if they are neighbors and if their opinions are sufficiently close to each other, below a given threshold of tolerance ǫ. In directed networks, if agent i is a neighbor of agent j, j need not be a neighbor of i. In Watts-Strogatz networks we performed simulations to find the averaged number of final opinions < F > and their distribution as a function of ǫ and of the network structural disorder. In directed networks < F > exhibits a rich structure, being larger than in undirected networks for higher values of ǫ, and smaller for lower values of ǫ.