Form-factors and current correlators: chiral couplings L_10(mu) and C_87(mu) at NLO in 1/N(C)

Using the resonance chiral theory Lagrangian, we perform a calculation of the vector and axial-vector two-point functions at the next-to-leading order (NLO) in the 1/N(C) expansion. We have analyzed these correlators within the single-resonance approximation and have also investigated the corrections induced by a second multiplet of vector and axial-vector resonance states. Imposing the correct QCD short-distance constraints, one determines the difference of the two correlators Pi(t) = Pi_VV(t)- Pi_AA(t) in terms of the pion decay constant and resonance masses. Its low momentum expansion fixes then the low-energy chiral couplings L_10 and C_87 at NLO, keeping full control of their renormalization scale dependence. At mu_0=0.77 GeV, we obtain L_10(mu_0) = (-4.4 \pm 0.9)10^{-3} and C_87^r(mu_0)=(3.1 \pm 1.1)10^{-5}

Self-organizing propagation patterns from dynamic self-assembly in monolayers

Propagation of localized orientational waves, as imaged by Brewster angle microscopy, is induced by low intensity linearly polarized light inside axisymmetric smectic-C confined domains in a photosensitive molecular thin film at the air/water interface (Langmuir monolayer). Results from numerical simulations of a model that couples photoreorientational effects and long-range elastic forces are presented. Differences are stressed between our scenario and the paradigmatic wave phenomena in excitable chemical media

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

The Effect of Pool Length on the Results of Professional Lifeguard Saving Tests

Todos los datos que han permitido la elaboración de este estudio, han sido facilitados por la Federación Madrileña de Salvamento y Socorrismo, por lo tanto, en este apartado se agradece la inestimable colaboración de esta entidad y de su equipo docenteEn este estudio se ha seleccionado a 2.528 aspirantes a la certificación de socorrista acuático (1.798 hombres y 730 mujeres). Todos ellos han realizado las cuatro pruebas físicas de agua cronometradas que se exigen para trabajar de socorrista en piscinas, instalaciones acuáticas y medio natural en la Comunidad Autónoma de Madrid (España). Del total de los participantes, 1.887 aspirantes realizaron dichas pruebas en vaso de 25 metros y 641 lo hicieron en vaso de 50 metros. El objetivo de este estudio es conocer la influencia de la longitud del vaso en el que se desarrollan estas pruebas físicas, sobre el porcentaje de aprobados y sobre las marcas de tiempo que emplean los participantes para realizarlas. Los resultados de esta investigación demuestran que la longitud del vaso en el que se evalúa a los aspirantes a socorrista, influye significativamente sobre las marcas de tiempo que obtienen y también sobre el número de aprobadosIn this study 2.528 aspirants for aquatic lifeguard certification (1.798 men and 730 women) were selected. All the participants of the study have performed the four physical tests of chronometric water required in order to work as a lifeguard for swimming pools, aquatic and open water in the Comunidad Autónoma de Madrid (Spain). Of the whole participants, 1.887 aspirants were tested in a 25-meter pool and 641 were done so in a 50-meter pool. The aim of this study is to know the influence of the length of the pool in which these physical tests are developed, on the pass rate and on the time needed by the sample to carry them out. The results of this research show that the length of the pool in which the aspirants are evaluated, influences on the time marks obtained by them and also on the number of approved one

Quantum Memristors

Technology based on memristors, resistors with memory whose resistance depends on the history of the crossing charges, has lately enhanced the classical paradigm of computation with neuromorphic architectures. However, in contrast to the known quantized models of passive circuit elements, such as inductors, capacitors or resistors, the design and realization of a quantum memristor is still missing. Here, we introduce the concept of a quantum memristor as a quantum dissipative device, whose decoherence mechanism is controlled by a continuous-measurement feedback scheme, which accounts for the memory. Indeed, we provide numerical simulations showing that memory effects actually persist in the quantum regime. Our quantization method, specifically designed for superconducting circuits, may be extended to other quantum platforms, allowing for memristor-type constructions in different quantum technologies. The proposed quantum memristor is then a building block for neuromorphic quantum computation and quantum simulations of non-Markovian systems

Setting up tunneling conditions by means of Bohmian mechanics

Usually tunneling is established after imposing some matching conditions on the (time-independent) wave function and its first derivative at the boundaries of a barrier. Here an alternative scheme is proposed to determine tunneling and estimate transmission probabilities in time-dependent problems, which takes advantage of the trajectory picture provided by Bohmian mechanics. From this theory a general functional expression for the transmission probability in terms of the system initial state can be reached. This expression is used here to analyze tunneling properties and estimate transmissions in the case of initial Gaussian wave packets colliding with ramp-like barriers.Comment: 18 pages, 4 figure