Diboson resonant production in non-custodial composite Higgs models

We show that the recently reported excess in resonant diboson production can be explained in the context of non-custodial composite Higgs models. Dibosons are generated via the s-channel exchange of massive vector bosons present in these models. We discuss the compatibility of the signal excess with other diboson experimental searches. We also discuss the tension between diboson production and other experimental tests of the model that include electroweak precision data, dilepton, dijet and top pair production and show that there is a region of parameter space in which they are all compatible with the excess.Comment: 15 pages, 2 figure

On the determinants of local tax rates: new evidence from Spain

This paper studies the determinants of local tax rates. For the two main local taxes in Spain - the property tax and the motor vehicle tax - we test the existence of tax mimicking, yardstick competition and political trends in a sample of 2,713 municipalities. Using different spatial models, the results support the hypothesis of tax mimicking, with coefficients over 0.40. We also show the relevance of political variables such as the ideology of the incumbents and political fragmentation. The fact that incumbents with weaker political support display stronger mimicking behaviour is interpreted as evidence in favour of yardstick competition. Finally, we find incumbents mimic neighbouring municipalities ruled by the same political party, confirming the political trends hypothesis.Local taxation, tax mimicking, yardstick competition, political trends

Localization and oscillations of Majorana fermions in a two-dimensional electron gas coupled with dd-wave superconductors

We study the localization and oscillation properties of the Majorana fermions that arise in a two-dimensional electron gas (2DEG) with spin-orbit coupling (SOC) and a Zeeman field coupled with a d-wave superconductor. Despite the angular dependence of the d-wave pairing, localization and oscillation properties are found to be similar to the ones seen in conventional s-wave superconductors. In addition, we study a microscopic lattice version of the previous system that can be characterized by a topological invariant. We derive its real space representation that involves nearest and next-to-nearest-neighbors pairing. Finally, we show that the emerging chiral Majorana fermions are indeed robust against static disorder. This analysis has potential applications to quantum simulations and experiments in high-$T_c$ superconductors.Comment: revtex4 file, color figure

Quantum Error Correction with the Semion Code

We present a full quantum error correcting procedure with the semion code: an off-shell extension of the double semion model. We construct open strings operators that recover the quantum memory from arbitrary errors and closed string operators that implement the basic logical operations for information processing. Physically, the new open string operators provide a detailed microscopic description of the creation of semions at their endpoints. Remarkably, topological properties of the string operators are determined using fundamental properties of the Hamiltonian, namely the fact that it is composed of commuting local terms squaring to the identity. In all, the semion code is a topological code that, unlike previously studied topological codes, it is of non-CSS type and fits into the stabilizer formalism. This is in sharp contrast with previous attempts yielding non-commutative codes.Comment: REVTeX 4 file, color figure

Quantum localized states in photonic flat-band lattices

The localization of light in flat-band lattices has been recently proposed and experimentally demonstrated in several configurations, assuming a classical description of light. Here, we study the problem of light localization in the quantum regime. We focus on quasi one-dimensional and two-dimensional lattices which exhibit a perfect flat-band inside their linear spectrum. Localized quantum states are constructed as eigenstates of the interaction Hamiltonian with a vanishing eigenvalue and a well defined total photon number. These are superpositions of Fock states with probability amplitudes given by positive as well as negative square roots of multinomial coefficients. The classical picture can be recovered by considering poissonian superpositions of localized quantum states with different total photon number. We also study the separability properties of flat band quantum states and apply them to the transmission of information via multi-core fibers, where these states allow for the total passive suppression of photon crosstalk and exhibit robustness against photon losses. At the end, we propose a novel on-chip setup for the experimental preparation of localized quantum states of light for any number of photons.Comment: 12 pages, 5 figure

Laboratorio de cálculo con la aplicación Desmos

En este trabajo se presenta un laboratorio de Cálculo elaborado con el software libre Desmos, la aplicación Weebly y el paquete JotForm. El laboratorio puede ser usado en diferentes dispositivos electrónicos como laptops, tabletas y teléfonos inteligentes, y se caracteriza por su versatilidad, facilidad de uso y portabilidad. Actualmente se usa en los cursos de cálculo para ingeniería del Tecnológico de Monterrey. El laboratorio contiene objetos de aprendizaje sobre derivación e integración de funciones de una y varias variables. Cada objeto tiene, a su vez: aplicación desarrollada en Desmos, guía para su uso, cuestionario de exploración de conceptos matemáticos, lista de ejercicios sobre el tema de la aplicación y un apartado para enviar los resultados al profesor. Al final, se muestran resultados de una encuesta de ambiente del aula sobre la utilidad del laboratorio

Consideraciones sobre la estabilidad y el funcionamiento de una coalición mínima mayoritaria: el caso del Ayuntamiento de Granada (1999-2001)

La longevidad de una coalición de gobierno se confunde frecuentemente con su estabilidad. El análisis del tiempo que los actores permanecen coaligados sustituye al juicio que es preciso hacer sobre los efectos políticos a los que dicha coalición da lugar. Frente a la consideración exclusiva de la cantidad de gobierno, es también preciso y útil tener en cuenta la calidad a la hora de examinar su solidez. Teniendo en cuenta esta habitual confusión, en el presente trabajo consideraremos dos momentos diferentes: por un lado, en la formación y en la agenda de gobierno de los tres partidos coaligados en el gobierno del Ayuntamiento de Granada tras las elecciones de marzo de 1999; por otro lado, en los efectos inmediatos y el grado de cumplimiento de la agenda en los dos primeros años de gobierno municipal. La comparación entre los proyectos y las materializaciones concretas, en un periodo tan corto, nos permitirá avanzar conclusiones provisionales en torno al verdadero pilar sobre el que se funda la estabilidad de la coalición: la calidad del gobierno. Al tiempo, y a partir de los datos obtenidos, avanzaremos una evaluación sobre el acierto o el fracaso de la coalición mínima mayoritaria pactada entre los tres partidos políticos presentes en el gobierno municipal del Ayuntamiento de Granada: PSOE, IU y PA.The longevity of a coalition in government is frequently confused with its stability as a coalition. The analysis on time of the longevity of the coalition usually replace the judgment about the effects of this coalition over the political system. Beyond the consideration about the time in power, seems useful to examine his stability and political effects over the system. In other words to keep in mind the «quality of the coalition government». Keeping in mind this common confusion, in this paper we will consider two different facts. On the one hand, coalition arraignment and the political agenda of the three parties in the city hall of Granada after the elections on March 1999. This parties are PSOE (Socialist Party), IU (United Left) and the PA (Andalusian nationalism). By the order, this article will examine the immediate political effects of coalition and the degree of fulfilment of the political agenda in the first two years in government. The comparison among political projects and his possibility to turn into real policies in a so short period, will allow us to advance some hypothesis about the real basement where the stability of the every coalition in government is rooted: the quality of the government. Considering data from 1999 and 2000 this paper will advance some conclusions about the successor the failure of this minimal winning coalition mainly from the perspective of the fulfilment of his pre electionary programs