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    The N=2N=2 super W4W_4 algebra and its associated generalized KdV hierarchies

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    We construct the N=2N=2 super W4W_4 algebra as a certain reduction of the second Gel'fand-Dikii bracket on the dual of the Lie superalgebra of N=1N=1 super pseudo-differential operators. The algebra is put in manifestly N=2N=2 supersymmetric form in terms of three N=2N=2 superfields Φi(X)\Phi_i(X), with Φ1\Phi_1 being the N=2N=2 energy momentum tensor and Φ2\Phi_2 and Φ3\Phi_3 being conformal spin 22 and 33 superfields respectively. A search for integrable hierarchies of the generalized KdV variety with this algebra as Hamiltonian structure gives three solutions, exactly the same number as for the W2W_2 (super KdV) and W3W_3 (super Boussinesq) cases.Comment: 16 pages, LaTeX, UTAS-PHYS-92-3

    Cherenkov gluons at RHIC and LHC

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    The coherent hadron production analogous to Cherenkov radiation of photons gives rise to the ring-like events. Being projected on the ring diameter they produce the two-bump structure recently observed for the away-side jets at RHIC. The position of the peaks and their height determine such properties of the hadronic medium as its nuclear index of refraction, the parton density, the free path length and the energy loss of Cherenkov gluons. Beside comparatively low energy gluons observed at RHIC, there could be high energy gluons at LHC, related to the high energy region of positive real part of the forward scattering amplitude and possessing different characteristics.Comment: 6 pages, talk at QM2006 modified with new reference

    Friedel oscillations at the surfaces of rhombohedral NN-layer graphene

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    The low-energy physics of rhombohedral NN-layer graphene mainly arises on the external layers, where most of the {\pi} electrons are located. Their Bloch band structure defines a two-band semimetal; the dispersion relation scales as ±qN\pm q^{N} with the momentum norm qq in the vicinity of two nonequivalent valleys. In this paper, we address the problem of elastic scattering through a localized impurity located either on the surface of the material or within the bulk, and focus on the quantum interferences it induces on the two external layers. It is apprehended in the framework of a TT-matrix approach, both numerically and analytically, regardless of the impurity magnitude, which enables the description of realistic scatters. In rhombohedral multilayer graphene, the impurity induces Friedel oscillations that always decay as 1/r1/r. As a result, monolayer graphene is the only material of the rhombohedral class that exhibits 1/r21/r^{2}-decaying Friedel oscillations. The interference patterns are subsequently analyzed in momentum space. This analysis enables a clear distinction between monolayer graphene and multilayer graphene. It also shows that the interference pattern reveals the whole Bloch band structure, and highlights the number of layers stacked in the material, as well as the π{\pi}-quantized Berry phases that characterize the existence of nodal points in the semimetallic spectrum. Experimentally, these features may be probed from scanning tunneling microscopy, when imaging the local density of states at the surfaces of suspended rhombohedral NN-layer graphene

    Visual Molecular Dynamics Investigations of the Impact of Hydrophobic Nanoparticles on Prognosis of Alzheimer’s Disease and Cancers

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    The possible impact of hydrophobic lectin nanoparticles on the prognosis and progression of Alzheimer's disease (AD) and cancers was investigated by Visual Molecular Dynamics (VMD) computer modeling programs available from the Beckmann Advanced Research Institute at the University of Illinois at Urbana. Our results indicate the possibility of impeding pathological aggregation of certain proteins such as modified tau- or beta-amyloid that are currently being considered as possible causes of Alzheimer's disease. VMD programs serve as useful tools for investigation hydrophobic protein aggregation that may play a role in aging of human populations

    On global location-domination in graphs

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    A dominating set SS of a graph GG is called locating-dominating, LD-set for short, if every vertex vv not in SS is uniquely determined by the set of neighbors of vv belonging to SS. Locating-dominating sets of minimum cardinality are called LDLD-codes and the cardinality of an LD-code is the location-domination number λ(G)\lambda(G). An LD-set SS of a graph GG is global if it is an LD-set of both GG and its complement G\overline{G}. The global location-domination number λg(G)\lambda_g(G) is the minimum cardinality of a global LD-set of GG. In this work, we give some relations between locating-dominating sets and the location-domination number in a graph and its complement.Comment: 15 pages: 2 tables; 8 figures; 20 reference
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