13,611 research outputs found

    Pseudoclassical model for Weyl particle in 10 dimensions

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    A pseudoclassical model to describe Weyl particle in 10 dimensions is proposed. In course of quantization both the massless Dirac equation and the Weyl condition are reproduced automatically. The construction can be relevant to Ramond-Neveu-Schwarz strings where the Weyl reduction in the Ramond sector has to be made by hand.Comment: 5 page

    Hermite polynomials, linear flows on the torus, and an uncertainty principle for roots

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    We study a recent result of Bourgain, Clozel and Kahane, a version of which states that a sufficiently nice function f:R→Rf:\mathbb{R} \rightarrow \mathbb{R} that coincides with its Fourier transform and vanishes at the origin has a root in the interval (c,∞)(c, \infty), where the optimal cc satisfies 0.41≤c≤0.640.41 \leq c \leq 0.64. A similar result holds in higher dimensions. We improve the one-dimensional result to 0.45≤c≤0.5940.45 \leq c \leq 0.594, and the lower bound in higher dimensions. We also prove that extremizers exist, and have infinitely many double roots. With this purpose in mind, we establish a new structure statement about Hermite polynomials which relates their pointwise evaluation to linear flows on the torus, and applies to other families of orthogonal polynomials as well.Comment: 26 pages, 4 figure

    Psychometric properties of Basic Empathy Scale among female juvenile delinquents and school youths

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    Research on empathy often distinguishes between affective and cognitive empathy, but there is limited knowledge regarding the application or measurement of these two dimensions of empathy among female youth, especially forensic samples of female youth. The main aim of the present study was to examine the psychometric properties of the Basic Empathy Scale (BES) among a Portuguese sample of female youths (N = 377), composed of incarcerated female juvenile offenders (n = 103) and school youths (n = 274). The two-factor structure of the BES obtained a good fit among the school sample, but the fit among the forensic sample was poor. Both samples demonstrated adequate psychometric properties in terms of Cronbach's alpha, omega coefficient, mean inter item correlations, corrected item-total correlation range, and criterion validity. However, some caution is advised when using the BES with female youth involved in the juvenile justice system, particularly with incarcerated female youth. (C) 2017 Elsevier Ltd. All rights reserved.European Social Fund (POPH/FSE)info:eu-repo/semantics/publishedVersio

    Tetraquark Production in Double Parton Scattering

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    We develop a model to study tetraquark production in hadronic collisions. We focus on double parton scattering and formulate a version of the color evaporation model for the production of the X(3872)X(3872) and of the T4cT_{4c} tetraquark, a state composed by the ccˉccˉc \bar{c} c \bar{c} quarks. We find that the production cross section grows rapidly with the collision energy s\sqrt{s} and make predictions for the forthcoming higher energy data of the LHC.Comment: 13 pages, 3 figures. Corrections in the text and reference

    The EU data protection reform and the challenges of big data: Tensions in the relations between technology and the law

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    In this article, we examine key features of the new EU General Data Protection Regulation (GDPR) in the light of implications of big data technologies. We will focus specifically on the original regulatory approaches introduced by the GDPR relying on risk assessment and management and on self-defense by Internet users, seeking to interpret them in view of a law-technology lag versus a law-technology driving perspective, meaning a legislative policy guided essentially by the intent to foster technological innovation and competitiveness in the Digital Single Market. Indeed, the current EU data protection reform seemingly fails to provide the appropriate caution that should be expected from a law designed to protect a fundamental human right. Notwithstanding the declared aspirations of the GDPR, the decision-making power on what and how to collect, store, and process personal data is leaning to the operators and data controllers to the disadvantage of data subjects and supervisory authorities. While technological conditions, namely the automatisation inherent to data mining and data analytics, render the effectiveness of key data protection principles harder to pursue, it is also true that the increasing suppleness of the regime is furthered by the Regulation’s own regulatory choices.info:eu-repo/semantics/publishedVersio
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