23,430 research outputs found

    The Hamiltonian Analysis for Yang-Mills Theory on RĂ—S2R\times S^2

    Full text link
    Pure Yang-Mills theory on RĂ—S2{\mathbb R} \times S^2 is analyzed in a gauge-invariant Hamiltonian formalism. Using a suitable coordinatization for the sphere and a gauge-invariant matrix parametrization for the gauge potentials, we develop the Hamiltonian formalism in a manner that closely parallels previous analysis on R3{\mathbb R}^3. The volume measure on the physical configuration space of the gauge theory, the nonperturbative mass-gap and the leading term of the vacuum wave functional are discussed using a point-splitting regularization. All the results carry over smoothly to known results on R3{\mathbb R}^3 in the limit in which the sphere is de-compactified to a plane

    Complementarity and Phase Distributions for Angular Momentum Systems

    Get PDF
    Interferences in the distributions of complementary variables for angular momentum - two level systems are discussed. A quantum phase distribution is introduced for angular momentum. Explicit results for the phase distributions and the number distributions for atomic coherent states, squeezed states and superpositions of coherent states are given. These results clearly demonstrate the issue of complementarity and provide us with results analogous to those for the radiation field.Comment: 9 pages, 3 figures available on request, replaced with minor typos corrected in abstract, to appear in Physics Letters

    Mesoscopic Superposition of States with Sub-Planck Structures in Phase Space

    Get PDF
    We propose a method using the dispersive interaction between atoms and a high quality cavity to realize the mesoscopic superposition of coherent states which would exhibit sub-Planck structures in phase space. In particular we focus on a superposition involving four coherent states. We show interesting interferences in the conditional measurements involving two atoms.Comment: 4-page 3-figur

    Numerical investigation of unsteady laminar incompressible co-axial boundary layer flows

    Get PDF
    Finite difference method for analysis of laminar incompressible boundary layer flows at jet exi

    Energy efficient engine, high pressure turbine thermal barrier coating. Support technology report

    Get PDF
    This report describes the work performed on a thermal barrier coating support technology task of the Energy Efficient Engine Component Development Program. A thermal barrier coating (TBC) system consisting of a Ni-Cr-Al-Y bond cost layer and ZrO2-Y2O3 ceramic layer was selected from eight candidate coating systems on the basis of laboratory tests. The selection was based on coating microstructure, crystallographic phase composition, tensile bond and bend test results, erosion and impact test results, furnace exposure, thermal cycle, and high velocity dynamic oxidation test results. Procedures were developed for applying the selected TBC to CF6-50, high pressure turbine blades and vanes. Coated HPT components were tested in three kinds of tests. Stage 1 blades were tested in a cascade cyclic test rig, Stage 2 blades were component high cycle fatigue tested to qualify thermal barrier coated blades for engine testing, and Stage 2 blades and Stage 1 and 2 vanes were run in factory engine tests. After completion of the 1000 cycle engine test, the TBC on the blades was in excellent condition over all of the platform and airfoil except at the leading edge above midspan on the suction side of the airfoil. The coating damage appeared to be caused by particle impingement; adjacent blades without TBC also showed evidence of particle impingement

    Vacuum induced Stark shifts for quantum logic using a collective system in a high quality dispersive cavity

    Get PDF
    A collective system of atoms in a high quality cavity can be described by a nonlinear interaction which arises due to the Lamb shift of the energy levels due to the cavity vacuum [Agarwal et al., Phys. Rev. A 56, 2249 (1997)]. We show how this collective interaction can be used to perform quantum logic. In particular we produce schemes to realize CNOT gates not only for two-qubit but also for three-qubit systems. We also discuss realizations of Toffoli gates. Our effective Hamiltonian is also realized in other systems such as trapped ions or magnetic molecules
    • …
    corecore