The Weinberg angle in the supersymmetric Weinberg-Salam model

The gauge theory based on the graded Lie group $\text{SU(}\text{2}\text{1}\text{)}$ (the so-called supersymmetric Weinberg-Salam model) attracted the attention of theorists some time ago, and attempts are now being made to incorporate this model into grand unified theories. Using a consistent normalization of the group generators, we wish to point out that the model predicts $\text{sin}{}^2\text{θ}{}_{\mathrm{<mtext>w</mtext>}}\text{=}\text{1}\text{2}$.     

A supersymmetric extension of the standard model with bilinear R-parity violation

The minimum supersymmetric standard model with bilinear R-parity violation is studied systematically. As we consider low-energy supersymmetry, we examine the structure of the bilinear R-parity violating model carefully. We analyze the mixing of, e.g., Higgs bosons with sleptons, neutralinos with neutrinos and charginos with charged leptons in the model. Possible and some important physics results, e.g. that the lightest Higgs may be heavier than the weak Z-boson at tree level, are obtained. The Feynman rules for the model are derived in the 't Hooft–Feynman gauge, which is convenient if perturbative calculations are needed beyond the tree level. Received: 26 April 1999 / Revised version: 28 June 1999 / Published online: 16 November 1999     

A supersymmetric extension of the Kadomtsev-Petviashvili hierarchy

An extension of the Kadomtsev-Petviashvili hierarchy by odd variables is given. Conservation laws and formal integrability are proved.     

Massive rigid string model and its supersymmetric extension

We discuss a rigid string model proposed by Casalbuoni and Longhi. Constraints for the massive states are solved to find the physical states and the mass spectrum. We also find its supersymmetric extension with the kappa symmetry. The supersymmetry transformations are found starting from on-shell transformations using the Dirac bracket.     

A supersymmetric extension of the Toda lattice hierarchy

A supersymmetric extension of the Toda lattice (STL) hierarchy is introduced. Explicit representation of solutions of the STL hierarchy is given by means of the Riemann-Hilbert decomposition. The STL hierarchy connected with the infinite-dimensional Lie super algebra osp (/) is studied.     

A new six-dimensional approach to the Weinberg-Salam model

The bosonic sector of the Weinberg-Salam model is derived from a 6-dimensional Yang-Mills theory by imposing rotational symmetry in the extra, compact dimensions. The Weinberg angle and the mass of the Higgs particle are predicted.     

A remark on divergence cancellations in the Weinberg-Salam model

An alternative proof of ultraviolet divergence cancellation (at the one-loop level) in certain ratios of renormalized coupling constants in the Weinberg-Salam model is suggested. Working in the unitary gauge, we use a simple coordinate-space method for manipulating Feynman integrals proposed by Kummer and Lane. In a particular example it is shown that this method provides an extremely useful tool for solving the problem.Dedicated to Academician Václav Votruba on the occasion of his seventieth birthday.     

New U(1) gauge extension of the supersymmetric standard model

In extending the minimal standard model of quarks and leptons to include supersymmetry, the conservation of baryon and lepton numbers is no longer automatic. I show how the latter may be achieved with a new U(1) gauge symmetry and new supermultiplets at the TeV scale. Neutrino masses and a solution of the mu problem are essential features of this proposed extension.     

A toy model for Hidden Weinberg-Salam Higgs particle

We show that in theSU(2)×U(1) model with one more Higgs singlet, the Weinberg-Salam Higgs can be made Hidden.     

A supersymmetric gluon model

It is pointed out that parity doubling does not provide a satisfactory resolution of the conflict between parity and fermion-number conservation in supersymmetric gauge theories. A new generalized gauge principle is proposed which overcomes this difficulty for both Abelian and non-Abelian local symmetries.     

Orthogonal polarization in the Weinberg-Salam model

We calculate the orthogonal polarization of the incoming lepton for the process ν'L→ν'L at the one-loop level in the Weinberg-Salam model.     

An additional symmetry in the Weinberg-Salam model

An additional Z₆ symmetry hidden in the fermion and Higgs sectors of the Standard Model has been found recently. It has a singular nature and is connected to the centers of the SU(3) and SU(2) subgroups of the gauge group. A lattice regularization of the Standard Model was constructed that possesses this symmetry. In this paper, we report our results on the numerical simulation of its electroweak sector.     

The Weinberg-Salam model and early cosmology

The consequences for cosmology of the phase transition in which SU(2)×U(1) symmetry is broken in the Weinberg-Salam model are discussed. The qualitative arguments concerning the effect of the phase transition on the baryon-to-entropy ratio that were recently posed by Witten for the case of a Coleman-Weinberg light Higgs boson are confirmed through exact numerical computations, but some quantitative disagreement is found. The computations are extended to the case in which the light Higgs boson is not of the Coleman-Weinberg type and the nature of the phase transition is discussed. Other cosmological effects are considered.