3,292 research outputs found

    Book Review: Euroscepticism within the EU institutions: diverging views of europe

    Get PDF
    Since its origins, there have been competing views concerning the nature, scope and objectives of the process of integration and of the European Union. Attitudes towards Europe and European integration, both among political elites and citizens, have been much studied over the last 15 years. But there is no comprehensive analysis of these competing views of Europe at the supranational level. Stuart A. Brown reviews Nathalie Brack and Olivier Costa’s edited collection on the divergence in views about the European Union, which lends insight into its consequences for the functioning of the EU and its institutions

    Entanglement in the classical limit: quantum correlations from classical probabilities

    Full text link
    We investigate entanglement for a composite closed system endowed with a scaling property allowing to keep the dynamics invariant while the effective Planck constant hbar_eff of the system is varied. Entanglement increases as hbar_eff goes to 0. Moreover for sufficiently low hbar_eff the evolution of the quantum correlations, encapsulated for example in the quantum discord, can be obtained from the mutual information of the corresponding \emph{classical} system. We show this behavior is due to the local suppression of path interferences in the interaction that generates the entanglement. This behavior should be generic for quantum systems in the classical limit.Comment: 10 pages 3 figure

    Closed orbits and spatial density oscillations in the circular billiard

    Full text link
    We present a case study for the semiclassical calculation of the oscillations in the particle and kinetic-energy densities for the two-dimensional circular billiard. For this system, we can give a complete classification of all closed periodic and non-periodic orbits. We discuss their bifurcations under variation of the starting point r and derive analytical expressions for their properties such as actions, stability determinants, momentum mismatches and Morse indices. We present semiclassical calculations of the spatial density oscillations using a recently developed closed-orbit theory [Roccia J and Brack M 2008 Phys. Rev. Lett. 100 200408], employing standard uniform approximations from perturbation and bifurcation theory, and test the convergence of the closed-orbit sum.Comment: LaTeX, 42 pp., 17 figures (24 *.eps files, 1 *.tex file); final version (v3) to be published in J. Phys.

    Periodic-orbit approach to the nuclear shell structures with power-law potential models: Bridge orbits and prolate-oblate asymmetry

    Full text link
    Deformed shell structures in nuclear mean-field potentials are systematically investigated as functions of deformation and surface diffuseness. As the mean-field model to investigate nuclear shell structures in a wide range of mass numbers, we propose the radial power-law potential model, V \propto r^\alpha, which enables a simple semiclassical analysis by the use of its scaling property. We find that remarkable shell structures emerge at certain combinations of deformation and diffuseness parameters, and they are closely related to the periodic-orbit bifurcations. In particular, significant roles of the "bridge orbit bifurcations" for normal and superdeformed shell structures are pointed out. It is shown that the prolate-oblate asymmetry in deformed shell structures is clearly understood from the contribution of the bridge orbit to the semiclassical level density. The roles of bridge orbit bifurcations in the emergence of superdeformed shell structures are also discussed.Comment: 20 pages, 23 figures, revtex4-1, to appear in Phys. Rev.

    Curvature Correction in the Strutinsky's Method

    Full text link
    Mass calculations carried out by Strutinsky's shell correction method are based on the notion of smooth single particle level density. The smoothing procedure is always performed using curvature correction. In the presence of curvature correction a smooth function remains unchanged if smoothing is applied. Two new curvature correction methods are introduced. The performance of the standard and new methods are investigated using harmonic oscillator and realistic potentials.Comment: 4 figures, submitted to Journal of Physics G: Nuclear and Particle Physic

    Critical Surgical Services and the Fragmented Patient

    Get PDF
    corecore