6,522 research outputs found

    The bosonic string and superstring models in 26+2 and 10+2 dimensional space--time, and the generalized Chern-Simons action

    Get PDF
    We have covariantized the Lagrangians of the U(1)_V * U(1)_A models, which have U(1)_V * U(1)_A gauge symmetry in two dimensions, and studied their symmetric structures. The special property of the U(1)_V * U(1)_A models is the fact that all these models have an extra time coordinate in the target space-time. The U(1)_V * U(1)_A models coupled to two-dimensional gravity are string models in 26+2 dimensional target space-time for bosonic string and in 10+2 dimensional target space-time for superstring. Both string models have two time coordinates. In order to construct the covariant Lagrangians of the U(1)_V * U(1)_A models the generalized Chern-Simons term plays an important role. The supersymmetric generalized Chern-Simons action is also proposed. The Green-Schwarz type of U(1)_V * U(1)_A superstring model has another fermionic local symmetry as well as \kappa-symmetry. The supersymmetry of target space-time is different from the standard one.Comment: 27 pages, no figure

    Towards a lattice calculation of the coefficients of the QCD chiral Lagrangian

    Get PDF
    We discuss a general strategy to compute the coefficients of QCD chiral Lagrangian by using the lattice regularization of QCD with Wilson fermions. This procedure requires the introduction of an effective Lagrangian for lattice QCD as an intermediate step in the calculation. The continuum QCD chiral Lagrangian can be then obtained by expanding the lattice effective Lagrangian in increasing powers of the external momenta. A suitable renormalization procedure is required to account for the chiral symmetry breaking introduced by the Wilson term in the lattice action. In anticipation of a numerical simulation, the lattice effective Lagrangian is computed analytically and investigated in the strong coupling and large NN limitComment: Talk presented at LATTICE96(chirality in qcd) , 3 pages, no figures. Latex file with espcrc2 styl

    TAKING CHARGE 2017: Satisfaction of Residents of Lincoln, Nebraska

    Get PDF
    Between June and August of 2017, a satisfaction survey was completed by more than 1,200 randomly-selected Lincolnites (a random sample, yielding confidence intervals ranging from +/- 1-3% for the full sample, and +/- 2-8% at the district level, at the 95% confidence level1). Listed below are the main findings from that survey, including those obtained from examining the overall sample, and from comparisons among Lincoln’s four City Council Districts. Overall Satisfaction Ratings ‱ On average, Lincoln residents reported greater satisfaction than dissatisfaction with most City services in 2017. The average levels of satisfaction were significantly above 3.0 (neutral) for 20 of 22 mean levels of service. As was the case in prior years, some of the highest ratings were given for overall quality of life and fire and emergency medical/ambulance services. This year, we also assessed satisfaction with police services, which was also rated very highly. ‱ The lowest rated service was street maintenance, which was also rated lowest in 2012 and 2015. Street maintenance was the only service upon which City residents, on average, expressed dissatisfaction (that is, a rating that was significantly different from neutral and reflecting dissatisfaction rather than satisfaction). Across districts, street maintenance was rated similarly low. ‱ Ease of car travel also was rated low, with an average rating that was not significantly different from neutral and was significantly lower than in 2012. Ease of car travel was rated lowest by residents living in District 2. ‱ Examination of the 5-year trends in satisfaction ratings for City services demonstrated more areas of satisfaction increase than decrease. Satisfaction with overall quality of life, appearance and cleanliness of the City, the City’s safety and security, recreational opportunities, employment opportunities, ease of bike travel, health department services, job creation/economic development, and snowplowing of City streets showed statistically significant improvement since 2012. Positive 2-year trends included satisfaction with fire and emergency medical services, Lincoln’s overall natural environment, management of sewage and storm water, and street maintenance; each of which increased significantly since 2015. ‱ There were fewer areas of satisfaction decrease. Though average ratings indicated more resident satisfaction than dissatisfaction, availability of affordable housing and City recycling and sustainability demonstrated a downward trend over the past five years. As previously noted, satisfaction with ease of car travel also showed a significant decrease since 2012, resulting in average ratings not significantly different from neutral in 2017

    A Nonliearly Dispersive Fifth Order Integrable Equation and its Hierarchy

    Full text link
    In this paper, we study the properties of a nonlinearly dispersive integrable system of fifth order and its associated hierarchy. We describe a Lax representation for such a system which leads to two infinite series of conserved charges and two hierarchies of equations that share the same conserved charges. We construct two compatible Hamiltonian structures as well as their Casimir functionals. One of the structures has a single Casimir functional while the other has two. This allows us to extend the flows into negative order and clarifies the meaning of two different hierarchies of positive flows. We study the behavior of these systems under a hodograph transformation and show that they are related to the Kaup-Kupershmidt and the Sawada-Kotera equations under appropriate Miura transformations. We also discuss briefly some properties associated with the generalization of second, third and fourth order Lax operators.Comment: 11 pages, LaTex, version to be published in Journal of Nonlinear Mathematical Physics, has expanded discussio

    Determination of nutrients in seawater by segmented–flow analysis with higher analysis rate and reduced interference on ammonia

    Get PDF
    A microbore continuous-flow analyser was used to determine ammonia, nitrite, nitrate and phosphate in seawater. Ninety samples per hour were measured by optimizing the hydraulic conditions and using a cadmium coil for nitrate reduction. The analysis range was extended and the detection limit was reduced by using two analytical ranges with automatic range-changing. Interference from magnesium on ammonia was investigated and reduced by using a different complexing agent. The results correlated well with a Japanese reference method

    Reference based contrast functions in a semi-blind context

    No full text
    International audienceWe deal with blind signal extraction in the framework of a convolutive mixture of independent sources. Considering so-called reference signals, we generalize former identifiability conditions. Based on this result, we propose to incorporate some a priori information in the references. We show the validity of reference based contrast functions in two semi-blind situations. The results are confirmed by computer simulation

    Twisted Superspace for N=D=2 Super BF and Yang-Mills with Dirac-K\"ahler Fermion Mechanism

    Full text link
    We propose a twisted D=N=2 superspace formalism. The relation between the twisted super charges including the BRST charge, vector and pseudo scalar super charges and the N=2 spinor super charges is established. We claim that this relation is essentially related with the Dirac-K\"ahler fermion mechanism. We show that a fermionic bilinear form of twisted N=2 chiral and anti-chiral superfields is equivalent to the quantized version of BF theory with the Landau type gauge fixing while a bosonic bilinear form leads to the N=2 Wess-Zumino action. We then construct a Yang-Mills action described by the twisted N=2 chiral and vector superfields, and show that the action is equivalent to the twisted version of the D=N=2 super Yang-Mills action, previously obtained from the quantized generalized topological Yang-Mills action with instanton gauge fixing.Comment: 36 page

    Transport criticality of the first-order Mott transition in a quasi-two-dimensional organic conductor, Îș\kappa-(BEDT-TTF)2_{2}Cu[N(CN)2_{2}]Cl

    Full text link
    An organic Mott insulator, Îș\kappa-(BEDT-TTF)2_{2}Cu[N(CN)2_{2}]Cl, was investigated by resistance measurements under continuously controllable He gas pressure. The first-order Mott transition was demonstrated by observation of clear jump in the resistance variation against pressure. Its critical endpoint at 38 K is featured by vanishing of the resistive jump and critical divergence in pressure derivative of resistance, ∣1R∂R∂P∣|\frac{1}{R}\frac{\partial R}{\partial P}|, which are consistent with the prediction of the dynamical mean field theory and have phenomenological correspondence with the liquid-gas transition. The present results provide the experimental basis for physics of the Mott transition criticality.Comment: 4 pages, 5 figure

    Mott Transition vs Multicritical Phenomenon of Superconductivity and Antiferromagnetism -- Application to Îș\kappa-(BEDT-TTF)2_2X --

    Full text link
    Interplay between the Mott transition and the multicritical phenomenon of d-wave superconductivity (SC) and antiferromagnetism (AF) is studied theoretically. We describe the Mott transition, which is analogous to a liquid-gas phase transition, in terms of an Ising-type order parameter η\eta. We reveal possible mean-field phase diagrams produced by this interplay. Renormalization group analysis up to one-loop order gives flows of coupling constants, which in most cases lead to fluctuation-induced first-order phase transitions even when the SO(5) symmetry exists betwen the SC and AF. Behaviors of various physical quantities around the Mott critical point are predicted. Experiments in Îș\kappa-(BEDT-TTF)2_2X are discussed from this viewpoint.Comment: 4 pages, 9 figures, to appear in J. Phys. Soc. Jp