130 research outputs found

    Quantum Hypothesis Testing and Non-Equilibrium Statistical Mechanics

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    We extend the mathematical theory of quantum hypothesis testing to the general WW^*-algebraic setting and explore its relation with recent developments in non-equilibrium quantum statistical mechanics. In particular, we relate the large deviation principle for the full counting statistics of entropy flow to quantum hypothesis testing of the arrow of time.Comment: 60 page

    Oblique surface waves at an interface of metal-dielectric superlattice and isotropic dielectric

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    We investigate the existence and the dispersion characteristics of surface waves that propagate at an interface between metal-dielectric superlattice and isotropic dielectric. Within the long wavelength limit, when the effective-medium approximation is valid, the superlattice behaves like a uniaxial plasmonic crystal with the main optical axes perpendicular to the metal-dielectric interfaces. We demonstrate that if such a semi-infinite plasmonic crystal is cut normally to the layer interfaces and brought into the contact with semi-infinite dielectric, a new type of surface modes can appear. The propagation of such modes obliquely to the optical axes occurs under favorable conditions that regard thicknesses of the layers, as well as the proper choice of dielectric permittivity of the constituent materials. We show that losses within the metallic layers can be substantially reduced by making the layers sufficiently thin. At the same time, a dramatic enlargement of the range of angles for oblique propagation of the new surface modes is observed. This can lead, however, to the field non-locality and consequently to the failure of the effective-medium approximation.Comment: 4 pages, 3 figure

    Stream-based dynamic data race detection

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    Detecting data races in modern code executing on multicore processors is challenging. Instrumentation-based techniques for race detection not only have a high performance impact, but also are not likely to be certified for safety-critical systems. This paper presents a data race detector based on the well-known lockset algorithm in the runtime verification language TeSSLa, which is a stream-based specification using dynamic data structures to record lock operations and memory accesses. Such a specification can then be instantiated with particular parameters to make it suitable for the more limited planned monitoring using field- programmable gate arrays

    A Zincian Chrome-Spinel from the Cr-Ba-Fe-Cu-Zn Deposit near Busovaca (Bosnia and Herzegovina)

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    The metamorphic complex of the Busovaca area is mostly composed of Upper Silurian-Lower Devonian metapelites, metapsammites and metarhyolites formed under low grade metamorphism at 350° to 450°C and 3 to 5 kbars. The ore minerals of the Busovaca deposit are: magnetite (with relics of zincian chrome-spinel), rimmed by ferrichromite, and pyrite, chalcopyrite, enargite, bornite and siegenite. The gangue minerals are: siderite, quartz, albite, hyalophane, muscovite, chromian-chlorite and manganoan ankerite. Proton microprobe analyses (PIXE) were made of samples A (core Ac of the slightly altered chrome-spinel), B (strongly altered chrome-spinel with Bc-core, Bfc-ferrichromite zones, Br-magnetite rim) and C (cryptically zoned magnetite with Cc-core and Cr-magnetite rim). The results are recalculated in formulae, and presented on separate diagrams. The optical investigations, microprobe analyses, beam-scan photographs, diffusion rates of Mg, Al, Zn, Cr, and Mn, and diagrams, allow the following conclusions to be made: (1) magmatic origin of the primary chrome-spinel, (2) the emplacement of the Zn was prior to the alteration under very low f02, most probably synchronous with the sulphide mineralization; (3) the alteration process took place in two phases: (a) the early stage volume-for-volume replacement and formation of the ferrichromite and magnetite zones, (b) the late stage characterized by decolourization and/or resorption, and/or dissolution of the core (patches, specks, “atoll structure”); (4) released Al, Cr, Mn, and Zn have been taken up by silicate, carbonate and oxide minerals forming chromian-chlorite, manganoan ankerite or contaminated siderite and pyrite; (5) the diffusion rates among Al, Zn, Cr, and Mn during different stages of the alteration have the following sequence: Al - Zn - Cr - Mn; (6) the optically unzoned magnetite crystals or aggregates originated in chrome-spinel; (7) the mineral assemblage of the Busovaca deposit co-exists with the surrounding metamorphic complex belonging to the greenschist facies

    A note on the Landauer principle in quantum statistical mechanics

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    The Landauer principle asserts that the energy cost of erasure of one bit of information by the action of a thermal reservoir in equilibrium at temperature T is never less than kTlog2kTlog 2. We discuss Landauer's principle for quantum statistical models describing a finite level quantum system S coupled to an infinitely extended thermal reservoir R. Using Araki's perturbation theory of KMS states and the Avron-Elgart adiabatic theorem we prove, under a natural ergodicity assumption on the joint system S+R, that Landauer's bound saturates for adiabatically switched interactions. The recent work of Reeb and Wolf on the subject is discussed and compared

    Conceptions and perceptions of student initiative held by elementary school teachers and students

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    The aim of this study is to provide empirical analysis of teachers' and students' understanding of the term student initiative and their perceptions of its manifestations in school environment. A total of 182 teachers and 223 8th grade students were asked to (1) provide associations to the term 'initiative', (2) to specify personal characteristics and behaviors of students with high initiative and (3) to report on the importance and levels of student initiative manifested in different domains of school functioning. Both teachers' and students' associative fields for the term initiative are extremely large and with weak associative strength, implying various diverse meanings. However, both groups consider student initiative as an important feature for school functioning and report on student initiative being manifested in different domains of school life. While there are some differences, both groups connect student initiative with success in school but not with the gender of the student, pointing out prosocial behavior in the school environment and dedication to learning, as well as readiness for additional engagement in the class. Implications for school practice are discussed in terms of changing teacher - student patterns of conversational activities and inclusion of complex and challenging tasks connected to learning material

    Single-photon-emitting optical centers in diamond fabricated upon Sn implantation

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    The fabrication of luminescent defects in single-crystal diamond upon Sn implantation and annealing is reported. The relevant spectral features of the optical centers (emission peaks at 593.5 nm, 620.3 nm, 630.7 nm and 646.7 nm) are attributed to Sn-related defects through the correlation of their photoluminescence (PL) intensity with the implantation fluence. Single Sn-related defects were identified and characterized through the acquisition of their second-order auto-correlation emission functions, by means of Hanbury-Brown-Twiss interferometry. The investigation of their single-photon emission regime as a function of excitation laser power revealed that Sn-related defects are based on three-level systems with a 6 ns radiative decay lifetime. In a fraction of the studied centers, the observation of a blinking PL emission is indicative of the existence of a dark state. Furthermore, absorption dependence from the polarization of the excitation radiation with about 45 percent contrast was measured. This work shed light on the existence of a new optical center associated with a group-IV impurity in diamond, with similar photo-physical properties to the already well-known Si-V and Ge-V emitters, thus providing results of interest from both the fundamental and applicative points of view.Comment: 10 pages, 4 figure

    Effect of Insulin and Insulin-Like Growth Factor I on Fetal Macrosomia in Healthy Women

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    The aim of the study was to determine the values of insulin, insulin-like growth factor I (IGF- I) and glucose in the umbilical cord blood of macrosomic ( 4000 g) and control (3,000–3,500 g) infants born to healthy mothers, and to assess their possible correlation with the newborns’ birth weight and maternal anthropometric parameters. A series of 207 macrosomic term infants, and 200 control term infants, born to healthy mothers with normal oral glucose tolerance test throughout gestation, were studied. The glucose concentration did not differ between the macrosomic and control group while macrosomic infants had significantly higher values of insulin and IGF-I. Female macrosomic infants had significantly higher levels of insulin and IGF-I than male macrosomic infants. The levels of insulin and IGF-I, but not levels of glucose, differed between the macrosomic and control group according to the maternal weight, height, pregestational body mass index, weight gain during gestation, and maternal birth weight. The maternal anthropometric parameters were significantly greater in the macrosomic infants. Accordingly, macrosomia was concluded to be a multifactorial condition

    Simplicity of eigenvalues in Anderson-type models

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    We show almost sure simplicity of eigenvalues for several models of Anderson-type random Schr\"odinger operators, extending methods introduced by Simon for the discrete Anderson model. These methods work throughout the spectrum and are not restricted to the localization regime. We establish general criteria for the simplicity of eigenvalues which can be interpreted as separately excluding the absence of local and global symmetries, respectively. The criteria are applied to Anderson models with matrix-valued potential as well as with single-site potentials supported on a finite box.Comment: 20 page

    One-dimensional Dirac operators with zero-range interactions: Spectral, scattering, and topological results

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    17 pagesInternational audienceThe spectral and scattering theory for 1-dimensional Dirac operators with mass mm and with zero-range interactions are fully investigated. Explicit expressions for the wave operators and for the scattering operator are provided. These new formulae take place in a representation which links, in a suitable way, the energies -\infty and ++\infty, and which emphasizes the role of ±m\pm m. Finally, a topological version of Levinson's theorem is deduced, with the threshold effects at ±m\pm m automatically taken into account
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