66 research outputs found

    Driving Operators Relevant: A Feature of Chern-Simons Interaction

    Full text link
    By computing anomalous dimensions of gauge invariant composite operators (ψˉψ)n(\bar\psi\psi)^n and (ϕϕ)n(\phi^*\phi)^n in Chern-Simons fermion and boson models, we address that Chern-Simons interactions make these operators more relevant or less irrelevant in the low energy region. We obtain a critical Chern-Simons fermion coupling, 1κc2=619{1\over \kappa_c^2} = {6\over 19}, for a phase transition at which the leading irrelevant four-fermion operator (ψˉψ)2(\bar\psi\psi)^2 becomes marginal, and a critical Chern-Simons boson coupling, 1κc2=634{1\over \kappa_c^2} = {6\over 34}, for a similar phase transition for the leading irrelevant operator (ϕϕ)4(\phi^*\phi)^4. We see this phenomenon also in the 1/N1/N expansion.Comment: (ten pages, latex, figures included

    A Critical Phenomenon in Solitonic Ising Chains

    No full text
    We discuss a phase transition of the second order taking place in non-local 1D Ising chains generated by specific infinite soliton solutions of the KdV and BKP equations

    Operator Relations for SU(3) Breaking Contributions to K and K* Distribution Amplitudes

    Full text link
    We derive constraints on the asymmetry a1 of the momentum fractions carried by quark and antiquark in K and K* mesons in leading twist. These constraints follow from exact operator identities and relate a1 to SU(3) breaking quark-antiquark-gluon matrix elements which we determine from QCD sum rules. Comparing our results to determinations of a1 from QCD sum rules based on correlation functions of quark currents, we find that, for a1^\parallel(K*) the central values agree well and come with moderate errors, whereas for a1(K) and a1^\perp(K*) the results from operator relations are consistent with those from quark current sum rules, but come with larger uncertainties. The consistency of results confirms that the QCD sum rule method is indeed suitable for the calculation of a1. We conclude that the presently most accurate predictions for a1 come from the direct determination from QCD sum rules based on correlation functions of quark currents and are given by: a1(K) = 0.06\pm 0.03, a1^\parallel(K*) = 0.03\pm 0.02, a1^\perp(K*) = 0.04\pm 0.03.Comment: 21 page

    Unit circle elliptic beta integrals

    Full text link
    We present some elliptic beta integrals with a base parameter on the unit circle, together with their basic degenerations.Comment: 15 pages; minor corrections, references updated, to appear in Ramanujan

    Properties of generalized univariate hypergeometric functions

    Get PDF
    Based on Spiridonov's analysis of elliptic generalizations of the Gauss hypergeometric function, we develop a common framework for 7-parameter families of generalized elliptic, hyperbolic and trigonometric univariate hypergeometric functions. In each case we derive the symmetries of the generalized hypergeometric function under the Weyl group of type E_7 (elliptic, hyperbolic) and of type E_6 (trigonometric) using the appropriate versions of the Nassrallah-Rahman beta integral, and we derive contiguous relations using fundamental addition formulas for theta and sine functions. The top level degenerations of the hyperbolic and trigonometric hypergeometric functions are identified with Ruijsenaars' relativistic hypergeometric function and the Askey-Wilson function, respectively. We show that the degeneration process yields various new and known identities for hyperbolic and trigonometric special functions. We also describe an intimate connection between the hyperbolic and trigonometric theory, which yields an expression of the hyperbolic hypergeometric function as an explicit bilinear sum in trigonometric hypergeometric functions.Comment: 46 page

    Elliptic hypergeometry of supersymmetric dualities II. Orthogonal groups, knots, and vortices

    Full text link
    We consider Seiberg electric-magnetic dualities for 4d N=1\mathcal{N}=1 SYM theories with SO(N) gauge group. For all such known theories we construct superconformal indices (SCIs) in terms of elliptic hypergeometric integrals. Equalities of these indices for dual theories lead both to proven earlier special function identities and new conjectural relations for integrals. In particular, we describe a number of new elliptic beta integrals associated with the s-confining theories with the spinor matter fields. Reductions of some dualities from SP(2N) to SO(2N) or SO(2N+1) gauge groups are described. Interrelation of SCIs and the Witten anomaly is briefly discussed. Possible applications of the elliptic hypergeometric integrals to a two-parameter deformation of 2d conformal field theory and related matrix models are indicated. Connections of the reduced SCIs with the state integrals of the knot theory, generalized AGT duality for (3+3)d theories, and a 2d vortex partition function are described.Comment: Latex, 58 pages; paper shortened, to appear in Commun. Math. Phy

    On Paragrassmann Differential Calculus

    Get PDF
    Explicit general constructions of paragrassmann calculus with one and many variables are given. Relations of the paragrassmann calculus to quantum groups are outlined and possible physics applications are briefly discussed. This paper is the same as the original 9210075 except added Appendix and minor changes in Acknowledgements and References. IMPORTANT NOTE: This paper bears the same title as the Dubna preprint E5-92-392 but is NOT identical to it, containing new results, extended discussions, and references.Comment: 19p

    Supersymmetric Higgs production in gluon fusion at next-to-leading order

    Full text link
    The next-to-leading order (NLO) QCD corrections to the production and decay rate of a Higgs boson are computed within the framework of the Minimal Supersymmetric Standard Model (MSSM). The calculation is based on an effective theory for light and intermediate mass Higgs bosons. We provide a Fortran routine for the numerical evaluation of the coefficient function. For most of the MSSM parameter space, the relative size of the NLO corrections is typically of the order of 5% smaller than the Standard Model value. We exemplify the numerical results for two scenarios: the benchmark point SPS1a, and a parameter region where the gluon-Higgs coupling at leading order is very small due to a cancellation of the squark and quark contributions.Comment: 27 pages, LaTeX, 31 embedded PostScript-files; v2: typos corrected, reformatted in JHEP style; accepted for publication in JHE

    Strange quark condensate from QCD sum rules to five loops

    Full text link
    It is argued that it is valid to use QCD sum rules to determine the scalar and pseudoscalar two-point functions at zero momentum, which in turn determine the ratio of the strange to non-strange quark condensates Rsu=R_{su} = \frac{}{} with (q=u,dq=u,d). This is done in the framework of a new set of QCD Finite Energy Sum Rules (FESR) that involve as integration kernel a second degree polynomial, tuned to reduce considerably the systematic uncertainties in the hadronic spectral functions. As a result, the parameters limiting the precision of this determination are ΛQCD\Lambda_{QCD}, and to a major extent the strange quark mass. From the positivity of RsuR_{su} there follows an upper bound on the latter: msˉ(2GeV)121(105)MeV\bar{m_{s}} (2 {GeV}) \leq 121 (105) {MeV}, for ΛQCD=330(420)MeV.\Lambda_{QCD} = 330 (420) {MeV} .Comment: Minor changes to Sections 2 and

    New Eaxactly Solvable Hamiltonians: Shape Invariance and Self-Similarity

    Get PDF
    We discuss in some detail the self-similar potentials of Shabat and Spiridonov which are reflectionless and have an infinite number of bound states. We demonstrate that these self-similar potentials are in fact shape invariant potentials within the formalism of supersymmetric quantum mechanics. In particular, using a scaling ansatz for the change of parameters, we obtain a large class of new, reflectionless, shape invariant potentials of which the Shabat-Spiridonov ones are a special case. These new potentials can be viewed as q-deformations of the single soliton solution corresponding to the Rosen-Morse potential. Explicit expressions for the energy eigenvalues, eigenfunctions and transmission coefficients for these potentials are obtained. We show that these potentials can also be obtained numerically. Included as an intriguing case is a shape invariant double well potential whose supersymmetric partner potential is only a single well. Our class of exactly solvable Hamiltonians is further enlarged by examining two new directions: (i) changes of parameters which are different from the previously studied cases of translation and scaling; (ii) extending the usual concept of shape invariance in one step to a multi-step situation. These extensions can be viewed as q-deformations of the harmonic oscillator or multi-soliton solutions corresponding to the Rosen-Morse potential.Comment: 26 pages, plain tex, request figures by e-mai
    corecore