37 research outputs found

    Non classical velocity statistics in a turbulent atomic Bose Einstein condensate

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    In a recent experiment Paoletti et al (Phys. Rev. Lett. 101, 154501, 2008) monitored the motion of tracer particles in turbulent superfluid helium and inferred that the velocity components do not obey the Gaussian statistics observed in ordinary turbulence. Motivated by their experiment, we create a small turbulent state in an atomic Bose-Einstein condensate, which enables us to compute directly the velocity field, and we find similar non-classical power-law tails. Our result thus suggests that non-Gaussian turbulent velocity statistics describe a fundamental property of quantum fluids. We also track the decay of the vortex tangle in the presence of the thermal cloud.Comment: 10 pages, 3 figure

    Coherent laminar and turbulent motion of toroidal vortex bundles

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    Motivated by experiments performed in superfluid helium, we study numerically the motion of toroidal bundles of vortex filaments in an inviscid fluid. We find that the evolution of these large-scale vortex structures involves the generalised leapfrogging of the constituent vortex rings. Despite three dimensional perturbations in the form of Kelvin waves and vortex reconnections, toroidal vortex bundles retain their coherence over a relatively large distance (compared to their size), in agreement with experimental observations.Comment: 22 pages, 12 figure

    Cognitive Information Processing

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    Contains reports on four research projects.National Science Foundation (Grant GK-33736X)Associated Press (Grant)National Institutes of Health (Grant 1 PO1 GM19428-01

    Cognitive Information Processing

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    Contains reports on six research projects.National Institutes of Health (Grant 5 PO1 GM14940-04)National Institutes of Health (Grant 5 PO1 GM15006-03)Joint Services Electronics Programs (U. S. Army, U. S. Navy, and U. S. Air Force) under Contract DA 28-043-AMC-02536(E

    Cognitive Information Processing

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    Contains reports on four research projects.Providence Gravure, Inc. (Grant)International Business Machines Corporation (Grant

    Cognitive Information Processing

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    Contains goals, background, research activities on one research project and reports on three research projects.Center for Advanced Television StudiesAmerican Broadcasting CompanyAmpex CorporationColumbia Broadcasting SystemsHarris CorporationHome Box OfficePublic Broadcasting ServiceNational Broadcasting CompanyRCA CorporationTektronix3M CompanyProvidence Gravure Co. (Grant)International Business Machines, Inc

    Durendal, translated: Islamic object genealogies in the chansons de geste

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    The transfer of Saracen arms into Frankish ownership is a leitmotif of many chansons de geste, but one whose significance for translatio imperii has yet to be elucidated. In this essay, I focus on the Chanson d’Aspremont, a twelfth-century epic set in Calabria that narrates the pre-history of Durendal, Roland’s sword of Song of Roland fame, as an object inherited by Roland from its former royal Muslim owner. Drawing on cultural history and a number of object-translation models derived from material and spolia studies, I read the sword’s symbolic transfer as evidence of Norman desire for and appropriation of former Fatimid imperium in Sicily

    Contextualizing legal norms: a multi-dimensional view of the 2014 legal capital reform in China

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    This paper intends to shed light on the contentious theme of the reception of legal transplantation in the host environment, by examining the 2014 legislative reform of legal capital in China, which at least on paper imitates the enabling settings of US Revised Model Business Corporation Act (RMBCA). The paper looks at the interconnections between national-specific contextual elements, the resultant complexities, and the spillover effects of transplanted configurations in the unique Chinese socio-cultural setting, implicating the discrepancy between the ‘law in practice’ and the borrowed words ‘on the books’, and suggesting the importance of gaining a holistic understanding of ‘law’ involving the legal traditions in both the donor country and the recipient nation
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