4,696 research outputs found

    Remarks on the Additional Symmetries and W-Constraints in the Generalized KdV Hierarchy

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    Additional symmetries of the pp-reduced KP hierarchy are generated by the Lax operator LL and another operator MM, satisfying res(MnLm+n/p)res (M^n L^{m+n/p}) = 0 for 1≤n≤p−11 \leq n \leq p-1 and m≥−1m \geq -1 with the condition that ∂L∂tkp{\partial L \over {\partial t_{kp}}} = 0, kk = 1, 2,..... We show explicitly that the generators of these additional symmetries satisfy a closed and consistent W-algebra only when we impose the extra condition that ∂M∂tkp=0{\partial M \over {\partial t_{kp}}} = 0.Comment: 10 pages, Plain Te

    The sTB-B Hierarchy

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    We construct a new supersymmetric two boson (sTB-B) hierarchy and study its properties. We derive the conserved quantities and the Hamiltonian structures (proving the Jacobi identity) for the system. We show how this system gives the sKdV-B equation and its Hamiltonian structures upon appropriate reduction. We also describe the zero curvature formulation of this hierarchy both in the superspace as well as in components.Comment: 15 pages, Te

    Light-Cone Quantization of the c=2 Matrix Model

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    We study the large NN limit of an interacting \td\ matrix field theory, whose perturbative expansion generates the sum over planar random graphs embedded in two dimensions. In the \lc\ quantization the theory possesses closed string excitations which become free as N→∞N\to\infty. If the longitudinal momenta are discretized, then the calculation of the free string spectrum reduces to finite matrix diagonalization, the size of the matrix growing as the cut-off is removed. Our numerical results suggest that, for a critical coupling, the \lc\ string spectrum becomes continuous. This would indicate the massless dynamics of the Liouville mode of \td\ gravity, which would constitute a {\it third} dimension of the string theory.Comment: 12 pages, (3 diagrams now available as postscript files from authors, 1 ref added), PUPT-133

    *-Trek II: *_n Operations, Open Wilson Lines and the Seiberg-Witten Map

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    Generalizations of the *-product (e.g. n-ary *_n operations) appear in various places in the discussion of noncommutative gauge theories. These include the one-loop effective action of noncommutative gauge theories, the couplings between massless closed and open string modes, and the Seiberg-Witten map between the ordinary and noncommutative Yang-Mills fields. We propose that the natural way to understand the *_n operations is through the expansion of an open Wilson line. We establish the connection between an open Wilson line and the *_n operations and use it to: (I) write down a gauge invariant effective action for the one-loop F^4 terms in the noncommutative N=4 SYM theory; (II) find the gauge invariant couplings between the noncommutative SYM modes and the massless closed string modes in flat space; (III) propose a closed form for the Seiberg-Witten map in the U(1) case.Comment: 30 pages, AMSLaTeX using JHEP.cls., clarifications made, misprints corrected, references adde

    Gauge Invariant Correlators in Non-Commutative Gauge Theory

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    Using perturbation theory, we explore the universal high momentum behavior of correlation functions of gauge invariant operators in planar noncommutative gauge theories. We find that the correlation functions are strongly enhanced when pairs of momenta become antiparallel. In particular, there is a transition from the previously noted exponential suppression of correlation functions at high momenta to a more field theoretic behavior when the momenta of pairs of operators antialign within a critical angle. Some of our calculations can be extrapolated to strong coupling, and in particular we are able to reproduce precisely the supergravity prediction for the behavior of two point functions, including the coupling dependence.Comment: 24 pages, LaTeX, 6 figure

    Tobacco use disorder and treatment: new challenges and opportunities

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    Tobacco use remains a global problem, and options for consumers have increased with the development and marketing of e-cigarettes and other new nicotine and tobacco products, such as heat-not-burn tobacco and dissolvable tobacco. The increased access to these new products is juxtaposed with expanding public health and clinical intervention options, including mobile technologies and social media. The persistent high rate of tobacco-use disorders among those with psychiatric disorders has gathered increased global attention, including successful approaches to individual treatment and organizational-level interventions. Best outcomes occur when medications are integrated with behavioral therapies and community-based interventions. Addressing tobacco in mental health settings requires training and technical assistance to remove old cultural barriers that restricted interventions. There is still low-hanging fruit to be gained in educating on the proper use of nicotine replacement medications, how smoking cessation can change blood levels of specific medications and caffeine, and how to connect with quitlines and mobile technology options. Future innovations are likely to be related to pharmacogenomics and new technologies that are human-, home-, and community-facing

    Loops in the Curvature Matrix Model

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    Macroscopic loop correlators are investigated in the hermitian one matrix model with the potential perturbed by the higher order curvature term. In the phase of smooth surfaces the model is equivalent to the minimal conformal matter coupled to gravity. The properties of the model in the intermediate phase are similar to that of the discretized bosonic string with the central charge C>1.C > 1. Loop correlators describe the effect of the splitting of the random surfaces. It is shown, that the properties of the surfaces are changed in the intermediate phase because the perturbation modifies the spectrum of the scaling operators.Comment: UPRF-92-340, 14 pages, 3 figures, LaTeX fil

    On the energy-momentum tensor in non-commutative gauge theories

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    We study the properties of the energy-momentum tensor in non-commutative gauge theories by coupling them to a weak external gravitational field. In particular, we show that the stress tensor of such a theory coincides exactly with that derived from a theory where a Seiberg-Witten map has been implemented (namely, the procedure is commutative). Various other interesting features are also discussed.Comment: 3 page
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