493,740 research outputs found

    Quantum Holonomies in (2+1)-Dimensional Gravity

    Get PDF
    We describe an approach to the quantisation of (2+1)-dimensional gravity with topology R x T^2 and negative cosmological constant, which uses two quantum holonomy matrices satisfying a q-commutation relation. Solutions of diagonal and upper-triangular form are constructed, which in the latter case exhibit additional, non-trivial internal relations for each holonomy matrix. Representations are constructed and a group of transformations - a quasi-modular group - which preserves this structure, is presented.Comment: 10 pages Latex no figure

    Use of W-Boson Longitudinal-Transverse Interference in Top Quark Spin-Correlation Functions: II

    Full text link
    This continuation of the derivation of general beam-referenced stage-two spin-correlation functions is for the analysis of top-antitop pair-production at the Tevatron and at the Large Hadron Collider. Both the gluon-production and the quark-production contributions are included for the charged-lepton-plus-jets reaction p p or p bar{p} --> t bar{t} --> (W^+ b)(W^- bar{b}) --> (l^{+} nu b)(W^- bar{b}). There is a simple 4-angle beam-referenced spin-correlation function for determination of the relative sign of, or for measurement of a possible non-trivial phase between the two dominant helicity amplitudes for t --> W^{+} b decay. There is an analogous function and tests for bar{t} --> W^{-} bar{b} decay. This signature requires use of the (t bar{t}) c.m.-energy of the hadronically decaying W-boson, or the kinematically equivalent cosine of the polar-angle of W-boson emission in the anti-top (top) decay frame. Spinors and their outer-products are constructed so that the helicity-amplitude phase convention of Jacob & Wick can be used throughout for the fixing of the signs associated with this large W-boson longitudinal-transverse interference effect.Comment: Continuation of hep-ph/0506240 to include gluon-production contribution; 3 "postscript" figures. Equation numbers as in published-on-line EPJ

    A hydrodynamic approach to the Bose-Glass transition

    Full text link
    Nonlinear hydrodynamics is used to evaluate disorder-induced corrections to the vortex liquid tilt modulus for finite screening length and arbitrary disorder geometry. Explicit results for aligned columnar defects yield a criterion for locating the Bose glass transition line at all fields.Comment: 8 pages, 2 figures. Contributed talk at the First ESF-Vortex Matter Conference in Agia Pelagia, Crete, September 199

    Blowing in the Wind: A Note of Thanks

    Full text link

    Constantine\u27s sword: the church and the Jews

    Get PDF

    Zoological results of a tour in the far east : Polyzoa Entoprocta and Ctenostomata

    Get PDF
    The Polyzoa discussed or described in this paper are all from fresh or brackish water. The majority are from the Tale Sap in the north-eastern part of the Malay Peninsula} but a few come from the Tai-Hu in the Kiangsu Province of China. I have also included notes on one Indian form. The following species are to be considered: ENTOPROCTA. Chitaspis athleticus, gen. et sp. nov., from the Tale Sap. CTENOSTOMATA. Alcyonidium mytili, Dalyell, from Indian estuaries, etc. Triticella pediceltata (Alder), from the Tale Sap. Bowerbankiacaudata, Hincks, from the Tale Sap and Perak. Paludicella elongata, Leidy, from the Tai-Hu. Paludicella pentagonalis, sp. nov., from the Tale Sap. Victorelta bengalensis, Annandale, from the Tale Sap. Hislopia cambodgiensis (Jullien), from the Tai-Hu. Hislopia malayensis. sp. nov., from Jalor in the Malay Peninsula. It will be as well to defer consideration of the biology and distribution of these species until I have been able to deal systematically with the Phylactolaemata and Cheilostomata collected on my tour. All that need be said here is that while the species of Paludicella and Hislopia are from fresh water, the others. on the list are from brackish water
    corecore