Nonclassical polarization dynamics in classical-like states

Quantum polarization is investigated by means of a trajectory picture based on the Bohmian formulation of quantum mechanics. Relevant examples of classical-like two-mode field states are thus examined, namely Glauber and SU(2) coherent states. Although these states are often regarded as classical, the analysis here shows that the corresponding electric-field polarization trajectories display topologies very different from those expected from classical electrodynamics. Rather than incompatibility with the usual classical model, this result demonstrates the dynamical richness of quantum motions, determined by local variations of the system quantum phase in the corresponding (polarization) configuration space, absent in classical-like models. These variations can be related to the evolution in time of the phase, but also to its dependence on configurational coordinates, which is the crucial factor to generate motion in the case of stationary states like those here considered. In this regard, for completeness these results are compared those obtained from nonclassical N00N states.Comment: 8 pages, 3 figure

Practical Application Of Uml Activity Diagrams For The Generation Of Test Cases

Software testing and debugging represents around one third of total effort in development projects. Different factors which have influence on poor practices of testing have been identified through specific surveys. Amongst several, one of the most important is the lack of efficient methods to exploit development models for generating test cases. This paper presents a new method for automatically generating a complete set of functional test cases from UML activity diagrams complementing specification of use cases. Test cases are prioritized according to software risk information. Results from experiences with more than 70 software professionals/experts validate benefits of the method. Participants also confirm its interest and effectiveness for testing needs of industry

Between fetishism and survival : is the scientific article an academic commodity?

This article discusses the possible meanings of the intense prevailing concern in academic circles over the notion of research productivity, as reflected in an excess number of articles published in various scientific journals. The numerical accounting of articles published by researchers in scientific journals with renowned academic status serves to legitimize academics in their fields of work, in various ways. In this sense, we suggest that scientific articles take on aspects of merchandise-as-fetish, according to Marx's theory of use-value and exchange-value and Benjamin's exposure value. Meanwhile, the biological notions of selection and evolution are used as metaphorical elements in "bibliographic Darwinism". There are references as to the possibility many of the prevailing bibliometric concerns serve as instruments for econometric analysis, especially to orient and enhance cost-effectiveness analysis in research investments of various orders and types, from the point of view of their economic return

Los escribas del Códice de Madrid. Metodología y análisis pre-iconográfico.

Uno de los objetivos del Proyecto de Investigación El Códice irocortesiano del Museo de América de Madrid era identificar a los distintos escribas que participaron en la creación de las imágenes que componen el manuscrito, pero exclusivamente a través de análisis estilísticos de las propias representaciones pictóricas. En este artículo ofrecemos una visión general de la metodologia creada a tal fin, además de una descripción de los resultados preliminares obtenidos durante el proceso de investigacion.One of the aims of the El Códice 7'rocartesiano del Museo de América de Madrid project was ¡he identification, on stylistic grounds only, of the scribes who created the imagery of this ancient manuscript. In this article, the methodological procedures and assumptions developed to his end are outlined and some preliminary conclusions highlighted

Premelting-Induced Smoothening of the Ice-Vapor Interface

We perform computer simulations of the quasiliquid layer of ice formed at the ice-vapor interface close to the ice Ih-liquid-vapor triple point of water. Our study shows that the two distinct surfaces bounding the film behave at small wavelengths as atomically rough and independent ice-water and water-vapor interfaces. For long wavelengths, however, the two surfaces couple, large scale parallel fluctuations are inhibited, and the ice-vapor interface becomes smooth. Our results could help explain the complex morphology of ice crystallites.Comment: postprint plus supplemental material with details on simulation and theor

Zeno dynamics in wave-packet diffraction spreading

We analyze a simple and feasible practical scheme displaying Zeno, anti-Zeno, and inverse-Zeno effects in the observation of wave-packet spreading caused by free evolution. The scheme is valid both in spatial diffraction of classical optical waves and in time diffraction of a quantum wave packet. In the optical realization, diffraction spreading is observed by placing slits between a light source and a light-power detector. We show that the occurrence of Zeno or anti-Zeno effects depends just on the frequency of observations between the source and detector. These effects are seen to be related to the diffraction mode theory in Fabry-Perot resonators.Comment: 7 pages, 8 figure