Size distributions of shocks and static avalanches from the Functional Renormalization Group

Interfaces pinned by quenched disorder are often used to model jerky self-organized critical motion. We study static avalanches, or shocks, defined here as jumps between distinct global minima upon changing an external field. We show how the full statistics of these jumps is encoded in the functional-renormalization-group fixed-point functions. This allows us to obtain the size distribution P(S) of static avalanches in an expansion in the internal dimension d of the interface. Near and above d=4 this yields the mean-field distribution P(S) ~ S^(-3/2) exp(-S/[4 S_m]) where S_m is a large-scale cutoff, in some cases calculable. Resumming all 1-loop contributions, we find P(S) ~ S^(-tau) exp(C (S/S_m)^(1/2) -B/4 (S/S_m)^delta) where B, C, delta, tau are obtained to first order in epsilon=4-d. Our result is consistent to O(epsilon) with the relation tau = 2-2/(d+zeta), where zeta is the static roughness exponent, often conjectured to hold at depinning. Our calculation applies to all static universality classes, including random-bond, random-field and random-periodic disorder. Extended to long-range elastic systems, it yields a different size distribution for the case of contact-line elasticity, with an exponent compatible with tau=2-1/(d+zeta) to O(epsilon=2-d). We discuss consequences for avalanches at depinning and for sandpile models, relations to Burgers turbulence and the possibility that the above relations for tau be violated to higher loop order. Finally, we show that the avalanche-size distribution on a hyper-plane of co-dimension one is in mean-field (valid close to and above d=4) given by P(S) ~ K_{1/3}(S)/S, where K is the Bessel-K function, thus tau=4/3 for the hyper plane.Comment: 34 pages, 30 figure

Quantum Chinos Game: winning strategies through quantum fluctuations

We apply several quantization schemes to simple versions of the Chinos game. Classically, for two players with one coin each, there is a symmetric stable strategy that allows each player to win half of the times on average. A partial quantization of the game (semiclassical) allows us to find a winning strategy for the second player, but it is unstable w.r.t. the classical strategy. However, in a fully quantum version of the game we find a winning strategy for the first player that is optimal: the symmetric classical situation is broken at the quantum level.Comment: REVTEX4.b4 file, 3 table

Optimal purification of thermal graph states

In this paper, a purification protocol is presented and its performance is proven to be optimal when applied to a particular subset of graph states that are subject to local Z-noise. Such mixed states can be produced by bringing a system into thermal equilibrium, when it is described by a Hamiltonian which has a particular graph state as its unique ground state. From this protocol, we derive the exact value of the critical temperature above which purification is impossible, as well as the related optimal purification rates. A possible simulation of graph Hamiltonians is proposed, which requires only bipartite interactions and local magnetic fields, enabling the tuning of the system temperature.Comment: 5 pages, 4 figures v2: published versio

Service Learning pada Mata Kuliah Desain Interior & Styling 4 Program Studi Desain Interior Universitas Kristen Petra

Service Learning di Universitas Kristen Petra adalah salah satu metode pembelajaran di universitas dengan tujuan menghubungkan proses pembelajaran dengan pengabdian masyarakat. Cara ini digunakan pada mata kuliah Desain Interior & Styling 4 program studi Desain Interior di Universitas Kristen Petra untuk mendesain ruang komunitas di Surabaya. Permasalahan yang dapat dirumuskan adalah adalah bagaimana implementasi dan pengaruh service learning pada mata kuliah Desain Interior & styling 4. Metode yang digunakan adalah metode pembelajaran service learning yang terdiri dari investigation, preparation and planning, action, reflection, demonstration serta metode perancangan design thinking yang terdiri dari enam tahapan yaitu understand, observe, point of view, ideate, prototype, dan test. Hasil dari kegiatan ini adalah service learning dapat diterapkan dengan baik diukur dari dampak positifnya. Mahasiswa dapat meningkatkan kemampuan intrapersonal dan interpersonal serta menambah keterampilan merancang. Suasana proses pembelajaran menjadi lebih koordinatif, menyenangkan, dan mudah dipahami. Pihak komunitas juga dapat meningkatkan pengenalan masyarakat terhadap komunitas

Deflection and Rotation of CMEs from Active Region 11158

Between the 13 and 16 of February 2011 a series of coronal mass ejections (CMEs) erupted from multiple polarity inversion lines within active region 11158. For seven of these CMEs we use the Graduated Cylindrical Shell (GCS) flux rope model to determine the CME trajectory using both Solar Terrestrial Relations Observatory (STEREO) extreme ultraviolet (EUV) and coronagraph images. We then use the Forecasting a CME's Altered Trajectory (ForeCAT) model for nonradial CME dynamics driven by magnetic forces, to simulate the deflection and rotation of the seven CMEs. We find good agreement between the ForeCAT results and the reconstructed CME positions and orientations. The CME deflections range in magnitude between 10 degrees and 30 degrees. All CMEs deflect to the north but we find variations in the direction of the longitudinal deflection. The rotations range between 5\mydeg and 50\mydeg with both clockwise and counterclockwise rotations occurring. Three of the CMEs begin with initial positions within 2 degrees of one another. These three CMEs all deflect primarily northward, with some minor eastward deflection, and rotate counterclockwise. Their final positions and orientations, however, respectively differ by 20 degrees and 30 degrees. This variation in deflection and rotation results from differences in the CME expansion and radial propagation close to the Sun, as well as the CME mass. Ultimately, only one of these seven CMEs yielded discernible in situ signatures near Earth, despite the active region facing near Earth throughout the eruptions. We suggest that the differences in the deflection and rotation of the CMEs can explain whether each CME impacted or missed the Earth.Comment: 18 pages, 6 figures, accepted in Solar Physic

A coupling matrix vision for mobile filtering devices with micro-acoustic wave technologies. A systematic approach

Con el espectro radioeléctrico cada vez más saturado, los filtros y duplexores son elementos claves de la tecnología en el mercado de dispositivos discretos para la telefonía móvil. El segmento de usuario de los sistemas de comunicaciones inalámbricas aprovecha las destacadas propiedades de los dispositivos filtrantes basados en resonadores acústicos. Generalmente, el diseño de dispositivos de onda acústica ha sido asumido por técnicas de optimización debido a las restrictivas limitaciones impuestas por la viabilidad tecnológica de los resonadores SAW y BAW, así como las exigentes especificaciones eléctricas. Una respuesta de transmisión muy restrictiva y factores tecnológicos muy limitantes conducen a hacer el diseño más y más complejo y una tarea muy desafiante. El objetivo del trabajo está enfocado en facilitar el diseño de filtros/duplexores y hacerlo más eficiente. En consecuencia, la formulación inicial del problema se ha centrado en la viabilidad tecnológica para implementar filtros de onda acústica. Proporcionar una metodología sistemática es útil para acelerar la curva de aprendizaje de nuevos diseñadores. Los filtros de microondas con elevada selectividad son posibles si sus funciones de transferencia incorporan ceros de transmisión finitos. La introducción de nodos no-resonantes (NRN) da la posibilidad de diseñar filtros con el máximo número de ceros de transmisión finitos sin tener que implementar acoplamientos directos entre la fuente y la carga. Además, las configuraciones en línea con NRN permiten la extracción de los elementos analíticamente. La típica configuración de filtro ladder presenta similitudes características de acuerdo con las redes de prototipo en línea con nodos resonantes y no-resonantes, que son las propiedades de modularidad, para controlar los ceros de transmisión con resonadores independientes, y respuestas completamente canonícas sin acoplamiento fuente-carga directo. Los elementos de la red pasobanda son dados por ecuaciones explícitas en términos de aquellos en los prototipos en línea con NRN que pueden ser sintetizados analíticamente. Como consecuencia, es posible definir una metodología de síntesis directa para obtener los parámetros pasobanda eléctricos de un filtro RF general que está basado en resonadores acústicos. Este trabajo presenta una metodología que proporciona un procedimiento de síntesis sistemático para diseñar filtros y duplexores ladder basados en resonadores de onda micro-acústica. La metodología de diseño utiliza un enfoque nodal basado en NRN y nodos resonantes. La representación de la red mediante una matriz de acoplamiento mixta de nodos resonantes y no resonantes es capaz de gestionar de forma eficiente las restricciones tecnológicas. El procedimiento es eficiente en tiempo, preciso en los resultados y proporciona un profundo entendimiento de las particulares interacciones que se producen entre las restricciones tecnológicas y el funcionamiento del dispositivo. Un completo paquete de software, con un simulador rápido, preciso y de fácil uso, ha sido desarrollado, permitiendo obtener diseños de primera etapa exitosos. Como resultado de la metodología sistemática, hemos desarrollado un método de diseño que combina y sistemáticamente gestiona redes filtrantes compuestas de bloques de polo extraído con bloques de resonadores acoplados, es decir, celdas ladder con secciones CRF. Además, la metodología has sido extendida exitosamente para tener en cuenta el diseño de divisores de potencia con respuesta filtrante por medio de dos topologías diferentes: la configuración ladder y las secciones CRF. La metodología propuesta ofrece una solución que combina el completo cumplimiento de las máscaras de espectro con topologías preparadas para acomodar las restricciones tecnológicas de la tecnología micro-acústica. La metodología ha sido desarrollada orientada nativamente a gestionar la tecnología, como es el ajuste de la limitación en el acoplo electromagnético, y basada en fundamentos de síntesis rigurosos.With a spectrum more and more overcrowded, filters and duplexers are drivers of the technology in the discrete device mobile market. The user segment of wireless communication systems takes profit of the outstanding performance of filtering devices based on acoustic resonators. Usually, the design of acoustic wave devices have been mainly entrusted to optimization techniques because the stringent constraints imposed by the technological feasibility of SAW and BAW resonators and the challenging electrical specifications. A stringent transmission response and very restrictive technological factors lead the design to a more and more complex and challenging task. The aim of the work is focused on easing the filters/duplexers designs and making it more efficient. Consequently, the initial formulation of the problem was focused on the technological feasibility of acoustic wave filters. Providing a systematic methodology is useful to accelerate the learning curve of new entrant designers. Microwave filters with high selectivity are possible if their transfer functions incorporates finite transmission zeros. The inclusion of non-resonant nodes gives the possibility of designing filters with the maximum number of finite transmission zeros without implementing direct couplings between source and load. Furthermore, inline configuration with NRN allows the extraction of the elements analytically. The common ladder filter configuration exhibits characteristic similarities regarding inline prototype networks with resonant and non-resonant nodes, which are the property of modularity, to control transmission zeros by independent resonators, and fully canonical response without a direct source-load coupling. The elements of the lowpass prototype are given by explicit equations in terms of those in in-line prototypes with non-resonating nodes that can be synthesized analytically. As a consequence it is possible to define a direct synthesis methodology to obtain the bandpass electric parameters of a general RF filter that is based on acoustic resonators. This work presents a methodology that provides a systematic synthesis procedure for designing ladder filters and duplexers based on acoustic wave resonators. The methodology uses a nodal approach based on resonating and non-resonating nodes. The coupling matrix representation with a mix of different nature nodes, resonant and non-resonant, is able to efficiently manage the technological restrictions. The procedure is time efficient, precise in the outcomes and provides a deep understanding of the particular interactions between technological constraints and device performance. A complete software package with fast, accurate and easy-to-use simulator has been developed, enabling starting point design success. As a result of the systematic methodology, we have developed a design method that combines and systematically manages a filtering network composed of extracted-pole blocks with coupling resonators blocks, so it is ladder cells with CRF sections. Moreover, the methodology has been successfully extended to take into consideration filtering power dividers by means of two different topologies: ladder configuration and CRF sections. The proposed methodology offers a solution that combines a complete spectrum fulfillment with topologies ready to accommodate technological constraints of micro-acoustics technologies. The methodology has been developed natively oriented to manage with the technology, such as accommodating electromechanical coupling constraints, leveraged in rigorous synthesis foundations

Systematics of the Relationship between Vacuum Energy Calculations and Heat Kernel Coefficients

Casimir energy is a nonlocal effect; its magnitude cannot be deduced from heat kernel expansions, even those including the integrated boundary terms. On the other hand, it is known that the divergent terms in the regularized (but not yet renormalized) total vacuum energy are associated with the heat kernel coefficients. Here a recent study of the relations among the eigenvalue density, the heat kernel, and the integral kernel of the operator $e^{-t\sqrt{H}}$ is exploited to characterize this association completely. Various previously isolated observations about the structure of the regularized energy emerge naturally. For over 20 years controversies have persisted stemming from the fact that certain (presumably physically meaningful) terms in the renormalized vacuum energy density in the interior of a cavity become singular at the boundary and correlate to certain divergent terms in the regularized total energy. The point of view of the present paper promises to help resolve these issues.Comment: 19 pages, RevTeX; Discussion section rewritten in response to referees' comments, references added, minor typos correcte

Protracted precarities : the residential mobilities of Poles in Scotland

Funding: ESRC (Grant Number(s): ES/N011430/1 and ES/J007374/1).The significant inflow of migrants to the United Kingdom following the Eastern EU Enlargement of 2004 is noteworthy due to its scale, intensity and geographic diversity. Recent statistical data suggest that these migrants exhibit spatial mobilities that reflect their disadvantage not just from the White British but also from other minority groups. Drawing on 83 interviews with Polish migrants living in Scotland, this paper illustrates the often‐persistent residential relocations experienced by this group postinternational migration and considers the drivers behind them. A key driver of this is the cycle of low paid and insecure employment that many migrants become entangled in, most frequently on arrival but often also longer term. These insights speak to wider debates about the scholarly dichotomy between international and internal migration and social inequalities in relation to labour market change and associated exposure to labour market and residential precarities.Publisher PDFPeer reviewe

The Optical Polarization and Warm Absorber in IRAS 17020+4544

We report the detection of ionized absorption in the ASCA spectrum of the narrow-line Seyfert 1 galaxy IRAS 17020+4544. Subsequent optical spectropolarimetry revealed high polarization increasing from 3% in the red to 5% in the blue, indicating electron or dust scattering as a likely origin. The broad emission line H$\alpha$ is somewhat less polarized than the continuum, supporting a location of the polarizing material within the AGN. The Balmer line decrement and reddened optical spectrum support the presence of a dusty warm absorber in this object. We compared the broad band optical polarization and ionized X-ray absorption of a collection of Seyfert 1 and 1.5 galaxies, excluding classes of objects that are likely to have significant neutral X-ray absorption. Warm absorber objects are generally more likely to have high optical polarization than objects with no detected ionized absorption. This result lends additional support to the idea that the warm absorber is associated with dust and implies either that dust transmission is responsible for at least part of the polarization or that the polarization is revealed because of the dimming of the optical spectrum. Spectropolarimetry of Seyfert 1s generally locates the scattering material inside the narrow-line region and often close to or within the broad line region, consistent with estimates of the location of the dusty warm absorber.Comment: 11 pages using (AASTeX) aaspp4.sty and 3 Postscript figures. Accepted for publication in Astrophysical Journal Letter

Best chirplet chain: near-optimal detection of gravitational wave chirps

The list of putative sources of gravitational waves possibly detected by the ongoing worldwide network of large scale interferometers has been continuously growing in the last years. For some of them, the detection is made difficult by the lack of a complete information about the expected signal. We concentrate on the case where the expected GW is a quasi-periodic frequency modulated signal i.e., a chirp. In this article, we address the question of detecting an a priori unknown GW chirp. We introduce a general chirp model and claim that it includes all physically realistic GW chirps. We produce a finite grid of template waveforms which samples the resulting set of possible chirps. If we follow the classical approach (used for the detection of inspiralling binary chirps, for instance), we would build a bank of quadrature matched filters comparing the data to each of the templates of this grid. The detection would then be achieved by thresholding the output, the maximum giving the individual which best fits the data. In the present case, this exhaustive search is not tractable because of the very large number of templates in the grid. We show that the exhaustive search can be reformulated (using approximations) as a pattern search in the time-frequency plane. This motivates an approximate but feasible alternative solution which is clearly linked to the optimal one. [abridged version of the abstract]Comment: 23 pages, 9 figures. Accepted for publication in Phys. Rev D Some typos corrected and changes made according to referee's comment