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Glenn D Starkman - One of the best experts on this subject based on the ideXlab platform.

  • global su 3 _c times su 2 _l times u 1 _y linear sigma model axial vector ward takahashi identities and decoupling of certain heavy bsm particles due to the goldstone theorem
    Physical Review D, 2017
    Co-Authors: Bryan W Lynn, Glenn D Starkman

    Dedicated to the memory of Raymond Stora (1930-2015). In the $SU(2)_L\times SU(2)_R$ Linear Sigma Model with PCAC, towers of Ward-Takahashi Identities (WTI) have long been known to give relations among 1-Scalar-Particle-Irreducible Green's functions, and among I- Scalar-Particle-Reducible T-Matrix elements, for external Scalars (i.e. the Brout-Englert-Higgs Scalar and 3 pseudoScalars). We extend these WTI and the resulting relations to the $SU(3)_C\times SU(2)_L\times U(1)_Y$ Linear Sigma Model including the heaviest generation of Standard Model (SM) fermions supplemented with the minimum necessary neutrino content -- right-handed neutrinos and Yukawa-coupling-induced Dirac neutrino mass. We extract powerful constraints on the effective Lagrangian: e.g. showing that they make separate tadpole renormalization unnecessary, and guarantee infra-red finiteness. Crucially, ultra-violet quadratic divergences (UVQD) and all other relevant operators contribute only to $m_\pi^2$, a Nambu-Goldstone boson (NGB) mass-squared. A WTI between T-Matrix elements (i.e. the Goldstone Theorem) then enforces $ m_\pi^2=0$ for the true NGB in the spontaneous symmetry breaking mode of the theory. All relevant operator contributions originating to all-loop-orders from virtual Scalars, quarks and leptons, vanish identically! Our regularization-scheme-independent results are unchanged by the addition of certain heavy CP-conserving matter, such as originate in certain Beyond the SM models. We demonstrate this with two examples: a heavy singlet real Scalar field with $Z_2$ symmetry and no VEV; and a heavy singlet right-handed Type I See-saw Majorana neutrino. Specifically, we prove that these heavy degrees of freedom decouple completely from the low-energy effective Lagrangian, contributing only irrelevant operators after quartic-coupling renormalization.

C N Pope - One of the best experts on this subject based on the ideXlab platform.

  • symmetric potentials of gauged supergravities in diverse dimensions and coulomb branch of gauge theories
    Physical Review D, 2000
    Co-Authors: Mirjam Cvetic, Steven S Gubser, C N Pope

    A class of conformally flat and asymptotically anti--de Sitter geometries involving profiles of Scalar fields is studied from the point of view of gauged supergravity. The Scalars involved in the solutions parametrize the SL(N,R)/SO(N) submanifold of the full Scalar coset of the gauged supergravity, and are described by a symmetric potential with a universal form. These geometries descend via consistent truncation from distributions of D3-branes, M2-branes, or M5-branes in ten or eleven dimensions. We exhibit analogous solutions asymptotic to AdS{sub 6} which descend from the D4-D8-brane system. We obtain the related six-dimensional theory by consistent reduction from massive type IIA supergravity. All our geometries correspond to states in the Coulomb branch of the dual conformal field theories. We analyze linear fluctuations of minimally coupled Scalars and find both discrete and continuous spectra, but always bounded below.

J Preethi - One of the best experts on this subject based on the ideXlab platform.

  • an novel key cryptography for signature depreciation in wireless sensor networks
    Wireless Communication, 2013
    Co-Authors: P Prema, J Preethi

    Koblitz introduced a family of curves which admit especially fast elliptic Scalar multiplication. A Koblitz curve is an elliptic curve has convenient features for efficient implementation of elliptic curve cryptography. In order to enable faster computations, Scalars need to be reduced and represented using a special base -expansion. Hence an efficient conversion algorithm is indeed which utilize only simple operations such as additions and shifts. It is an attractive class of elliptic curves because they offer faster Scalar multiplications. It is also the most demanding operation due to its efficient computation which is widely used in practical cryptosystems.

Wilfried Brutsaert - One of the best experts on this subject based on the ideXlab platform.

  • The Effect of Chessboard Variability of the Surface Fluxes on the Aggregated Turbulence Fields in a Convective Atmospheric Surface Layer
    Boundary-Layer Meteorology, 1999
    Co-Authors: Jun Asanuma, Wilfried Brutsaert

    To what degree the variability of surface features can be identified in the turbulent signals observed in the atmospheric boundary layer is still an unresolved problem. This was investigated by conducting an analytical experiment for a one-dimensional 'chessboard'-type surface-flux distribution on the basis of local free convection scaling. The results showed that, due to their nonlinear dependency on the surface fluxes, the dimensionless gradients of the mean quantities and the dimensionless standard deviations are altered by the surface-flux variability. Furthermore, passive Scalars, such as humidity, are considerably more sensitive to surface variability than the main active Scalar, temperature. However, the response of the gradients of the mean quantities is fairly negligible in the range of variability studied herein as compared to that of the standard deviations, which were found to be more sensitive to the surface-flux variability. In addition, the phase difference between the active and the passive Scalar flux distribution strongly affects the passive Scalar turbulence. This dissimilarity between passive and active Scalars, or between passive Scalars when their source distributions are different, brings into question the use of variance methods for the measurement of a Scalar flux, such as evaporation, over variable surfaces. The classical Bowen ratio method, which depends on the validity of the Reynolds analogy for the vertical gradients of the mean quantities, was shown to be relatively more robust. However, under conditions of strong surface variability, it can also be expected to fail.

Warren C. Strahle - One of the best experts on this subject based on the ideXlab platform.

  • Pressure-density correlation in a turbulent reacting flow
    Combustion and Flame, 1991
    Co-Authors: G.a. Waldherr, W.c. Degroot, Warren C. Strahle

    Progress toward extraction of the elusive pressure-density correlation in variable density reacting flows is reported, using a premixed methane-air flame in open surroundings as the test medium. The relationship among density and other Scalars is shown. Molecular Rayleigh scattering, laser Doppler velocimetry, and dynamic Pitot barometry are the experimental techniques used. It is shown that the often neglected pressure-Scalar correlation is an important quantity in Scalar transport and must be taken into account theoretically in ways that differ from past treatment.