Superstring on pp-wave orbifold from large-N quiver gauge theory

We extend the proposal of Berenstein, Maldacena and Nastase to the Type IIB superstring propagating on a pp-wave over the R ⁴/Z _k orbifold. We show that first-quantized free string theory is described correctly by the large-N, fixed gauge coupling limit of [U(N)] ^k quiver gauge theory. We propose a precise map between gauge theory operators and string states for both untwisted and twisted sectors. We also compute leading-order perturbative correction to the anomalous dimensions of these operators. The result is in agreement with the value deduced from the string energy spectrum, thus substantiating our proposed operator-state map. Received: 14 March 2002 / Published online: 5 July 2002     

Quantisation of a gauge field in the temporal-like gauge based on stochastic mechanics

Stochastic mechanics can be applied consistently to quantise gauge field in the temporal-like gauges such as the flow gauges, static gauges and the fully fixed temporal gauges.     

Cabibbo current and CP violation in a six quark gauge model

The extended Cabibbo current with CP-violation in a six quark gauge model is obtained in terms of quark mass ratios and phases in the quark mass matrices. The model predicts a long-lived heavy quark and its selection rule.     

The estimation of the Z′ gauge boson mass in E 6 models

The aim of this study is to estimate the Z′ boson mass by using the calculations of the decay width of Z′(ϑ) boson. So, the decay width of the extra Z boson is calculated numerically in effective rank 5 models for different mixing angles ϑ of the model and for different mass values of the extra Z boson. The decay width of Z′ boson to the Standard Model (SM) fermions is found to be between 4.42 and 19.36 GeV and the full decay width of Z′ boson to all particles is found to be between 20.88 and 37.15 GeV. We calculated the full decay width at the angle ϑ ≊ 0 for Z′ and Z ₂ → Z′. The full decay width of Z′ boson is written in a single equation according to our calculations. By using these calculations and the previous works the mass of Z′ boson and the number of generations of the exotic particles are estimated. The article is published in the original.     

A six-dimensional gauge-Higgs unification model based on E6 gauge symmetry

We construct a six-dimensional gauge-Higgs unification model with the enlarged gauge group of E₆ on S²/Z₂$S^2/Z_2$ orbifold compactification. The standard model particle contents and gauge symmetry are obtained by utilizing a monopole background field and imposing appropriate parity conditions on the orbifold. In particular, a realistic Higgs potential suitable for breaking the electroweak gauge symmetry is obtained without introducing extra matter or assuming an additional symmetry relation between the SU(2) isometry transformation on the S²$S^2$ and the gauge symmetry. The Higgs boson is a KK mode associated with the extra-dimensional components of gauge field. We also compute the KK masses of all fields at tree level.     

Two dimensional lattice gauge theory based on a quantum group

In this article we analyse a two dimensional lattice gauge theory based on a quantum group. The algebra generated by gauge fields is the lattice algebra introduced recently by A.Yu. Alekseev, H. Grosse and V. Schomerus in [1]. We define and study Wilson loops. This theory is quasi-topological as in the classical case, which allows us to compute the correlation functions of this theory on an arbitrary surface.Laboratoire Propre du CNRS UPR 14     

A gauge theory of gravitation based on a specific Lagrangian

The paper is devoted to the presentation of a specific Lagrangian for the Poincaré gauge theory of gravity. Interesting and useful properties of the gauge theory of gravitation based on this Lagrangian are briefly outlined.     

Supersymmetry breaking and gauge mediation in models with a generic superpotential

We present a general scheme for finding or creating a metastable vacuum in supersymmetric theories. By using the formalism, we show that there is a parameter region where a metastable vacuum exists in the Wess–Zumino model coupled to messenger fields. This model serves as a perturbative renormalizable model of direct gauge mediation.     

Neutral-current constraints on gauge models of weak and electromagnetic interactions

Sehgal and Hung and Sakurai have recently argued that neutrino-hadron neutral-current couplings must lie in one of two allowed regions in coupling-parameter space. We study this conjecture using realistic BNL ν_μ and ν̄_μ spectra in the elastic ν_μp (ν̄_μp) calculations and also study constraints imposed by theq²-distributions. On comparing to gauge models, we find that the Weinberg-Salam and SU(2)_L×SU(2)_R×U(1) models fall within one allowed region, while a vectorlike SU(3)×U(1) model and a hybrid SU(2)×U(1) model with a (u, b)_R doublet fall in the other region.     

Mechanical impedance gauge based on measurement of strains on a vibrating rod

An impedance gauge based on measurement of strains at two different cross-sections of a vibrating rod is analyzed and tested. The gauge rod, which may have variable characteristic impedance, is in contact with the object at one end and is driven by a harmonic vibrator at the other end. For conical and cylindrical rods explicit relations between point impedance and measured strains are derived. For a cylindrical gauge rod of steel with length 800 mm, diameter 10 mm, and distance between strain gauges 250 mm a fair agreement was generally obtained between experimental and theoretical point impedances of cylindrical test objects in the frequency range 50 Hz to 1·7 kHz. Significant improvements in accuracy over that of the tested prototype are expected to be feasible.     

E6 as a unifying gauge symmetry

Some consequences of embedding gauge models of strong, weak and electromagnetic interactions in the exceptional group E₆ are presented.     

Opto-electronic displacement gauge based on speckle interferometer

Modern technology demands precise distance measurements. People have used many phenomena for this purpose but there is always a need for less expensive and more reliable devices. In this paper we present a simple opto-electronic distance measurement gauge based on the phenomenon of speckling phenomenon. In the proposed setup we substitute diffraction gratings, which are commonly used in displacement gauges, with a rough surface. When illuminated by a coherent and monochromatic beam the surface scatters light to form a speckle field, whose intensity variations are read by one or more detectors. These changes are related to displacement of the rough surface and, therefore, can be utilized for displacement measurements. The presented setup has some important advantages over the grating approach: lower mechanical tolerances on parts and being based directly on the wavelength of light instead of the period of a grating. Also, it is less expensive, so can offer a viable solution for medium accuracy distance measurements.     

Constraints on the parameters of the left-right symmetric gauge models

We find an important constraint on the parameters of the general four-parameter left-right symmetric model. The constraint links the v-hadron sector of the model with the parity-violation sector. Using this constraint along with the available neutral-current data from neutrino-hadron and electron-deuteron scattering we find that, except for a narrow region amounting to essentially one point in the four-parameter space, the model is excluded.     

New cosmological models in the framework of a gauge theory of gravity

The paper is devoted to the presentation of the new cosmological solutions obtained by the author within the framework of a gauge theory of gravitation. The models are a combination of evolving models and steady-state models.     

Renormalization of scalar quartic and Yukawa couplings in unified gauge theories based onE 6

Renormalization group equations for scalar and Yukawa couplings in gauge theories based on the exceptional groupE ₆ are analyzed. Asymptotic freedom is possible only for a limited set of scalar fields, and then only if several fermion generations are present. The infrared behavior of the scalar quartic coupling constants is striking: they are necessarily driven out of the region of positivity of the classical potential. Some useful group theoretic relations inE ₆ are given in an Appendix.     

Height gauge based on dual polarization competition laser

Based on dual polarization competition laser, we develop a new height gauge. By inserting a quartz crystal plate into the laser cavity, one laser beam splits into two orthogonally linear polarized laser beams, which appear one after another with the change in cavity length. After detecting their intensities, we obtain two power-turning curves. The longitudinal mode spacing is divided into 4 equal zones and each one has different intensity phenomena, which provides a new method of height measurement. According to experiments, the direct measuring range of this new method is 12 mm with resolution of 79.1 nm, and the indirect measuring range can be increased using first grade gauge blocks and a liftable platform. Compared to other height gauges such as vernier gauge, inductance sensor and gauge block interferometer, this new instrument has the advantage of self-calibration and simple structure without frequency stabilization system.