Multi-state Boson Stars

Motivated by the increasing interest in models which consider scalar fields as viable dark matter candidates, we have constructed a generalization of relativistic Boson Stars (BS) composed of two coexisting states of the scalar field, the ground state and the first excited state. We have studied the dynamical evolution of these Multi-state Boson Stars (MSBS) under radial perturbations, using numerical techniques. We show that stable MSBS can be constructed, when the number of particles in the first excited state, N2, is smaller than the number of particles in the ground state, N1. On the other hand, when N2 > N1, the configurations are initially unstable. However, they evolve and settle down into stable configurations. In the stabilization process, the initially ground state is excited and ends in a first excited state, whereas the initially first excited state ends in a ground state. During this process, both states emit scalar field radiation, decreasing their number of particles. This behavior shows that even though BS in the first excited state are intrinsically unstable under finite perturbations, the configuration resulting from the combination of this state with the ground state produces stable objects. Finally we show in a qualitative way, that stable MSBS could be realistic models of dark matter galactic halos, as they produce rotation curves that are flatter at large radii than the rotation curves produced by BS with only one state.Comment: 14 pages. Extended discussion and new figures added. Conclusions unchanged. Accepted for publication in Physical Review

Installation process and main functionalities of the Spin model checker

This document explains how to download and install all the software needed to properly run the Spin model checker and its user-friendly graphical user interface, called iSpin. It also offers a short tutorial which presents the main functionalities of Spin and explains briefly some basic concepts which are important to be able to use Spin through iSpin.Grupo de investigación MYDASS (Modelling & Development of Advanced Software Systems), TIC-230. Departamento de Lenguajes y Sistemas Informáticos (Universidad de Granada)

NeuroPod: a real-time neuromorphic spiking CPG applied to robotics

Initially, robots were developed with the aim of making our life easier, carrying out repetitive or dangerous tasks for humans. Although they were able to perform these tasks, the latest generation of robots are being designed to take a step further, by performing more complex tasks that have been carried out by smart animals or humans up to date. To this end, inspiration needs to be taken from biological examples. For instance, insects are able to optimally solve complex environment navigation problems, and many researchers have started to mimic how these insects behave. Recent interest in neuromorphic engineering has motivated us to present a real-time, neuromorphic, spike-based Central Pattern Generator of application in neurorobotics, using an arthropod-like robot. A Spiking Neural Network was designed and implemented on SpiNNaker. The network models a complex, online-change capable Central Pattern Generator which generates three gaits for a hexapod robot locomotion. Recon gurable hardware was used to manage both the motors of the robot and the real-time communication interface with the Spiking Neural Networks. Real-time measurements con rm the simulation results, and locomotion tests show that NeuroPod can perform the gaits without any balance loss or added delay.Ministerio de Economía y Competitividad TEC2016-77785-

La radiología en las publicaciones periódicas de la disciplina enfermera.

Sin resume

Schwarzschild black holes can wear scalar wigs

We study the evolution of a massive scalar field surrounding a Schwarzschild black hole and find configurations that can survive for arbitrarily long times, provided the black hole or the scalar field mass is small enough. In particular, both ultra-light scalar field dark matter around supermassive black holes and axion-like scalar fields around primordial black holes can survive for cosmological times. Moreover, these results are quite generic, in the sense that fairly arbitrary initial data evolves, at late times, as a combination of those long-lived configurations.Comment: 5 pages, 3 figures. Accepted for publication in Physical Review Letter

Bill Kohn: la naturaleza infatigable

Entrevista del profesor Francisco J. Lara-Barranco a Bill Kohn, artista y profesor emérito de Washington University School of Art.Ministerio de Educación y Cultur

Procesos de creación artística I: María A. A., Juan Carlos Lázaro y Javier Velasco

Procesos de creación artística surge con un objetivo fundamental: que el alumno conozca diferentes modos de producción en el terreno del arte. La idea se gestó en el año académico 2000-2001, y desde entonces se viene desarrollando. Básicamente, consiste en invitar a un artista o persona relacionada con la cultura, para que imparta una conferencia a cerca de su trabajo en la asignatura que imparto, Iniciación al Colorido, adscrita el Departamento de Pintura dentro del primer ciclo de la licenciatura en Bellas Artes. Generalmente, se hace coincidir la conferencia con una exposición que esté desarrollando el invitado en la ciudad de Sevilla. La razón de tal proceder radica en lo siguiente: el alumno puede tener un contacto directo con las obras. Durante la conferencia se aborda el proceso de creación específico desarrollado por la persona invitada. Durante el período señalado, visitaron la clase los invitados siguientes: María A.A. (artista multimedia), Javier Buzón (pintor), Diego Gadir (pintor), Dionisio González (artista multimedia), Juan Carlos Lázaro (pintor), Pedro Mora (artista multimedia) y Javier Velasco (artista multimedia)

Douglas Huebler

Douglas Huebler fue uno de los representantes más destacados del Arte Conceptual en los Estados Unidos. En sus comienzos, tras una breve incursión por las prácticas expresionistas, desarrolló una producción de estética visual minimalista. Desde 1968 buscó metodologías alternativas de creación: el descubrimiento del mapa (empleo del lenguaje asociado a una reunión de imágenes) le permitió transmitir al observador de cada obra una “imagen mental” diferenciada y con ello un entendimiento individualizado de la pieza. Sus intereses creativos se han focalizado, continuamente, en la realización de proyectos neutrales, con la premisa de que el observador no resultara “inhibido” a causa de la imagen proyectada por la obra

Spiking row-by-row FPGA Multi-kernel and Multi-layer Convolution Processor.

Spiking convolutional neural networks have become a novel approach for machine vision tasks, due to the latency to process an input stimulus from a scene, and the low power consumption of these kind of solutions. Event-based systems only perform sum operations instead of sum of products of framebased systems. In this work an upgrade of a neuromorphic event-based convolution accelerator for SCNN, which is able to perform multiple layers with different kernel sizes, is presented. The system has a latency per layer from 1.44 μs to 9.98μs for kernel sizes from 1x1 to 7x7