Related papers: Minimal Lee-Wick Extension of the Standard Model
We update our previous work on an analysis of the electroweak data by including new and partly preliminary data available up to the 1996 summer conferences. The new results on the Z partial decay widths into b and c hadrons now offer a…
We review the empirical evidence for the validity of the Standard Electroweak Theory in Nature. The experimental data are interpreted in terms of an effective Lagrangian for Z physics, allowing for potential sources of SU(2) violation and…
We consider the two Higgs doublet model extension of the Standard Model in the limit where all physical scalar particles are very heavy; too heavy, in fact, to be experimentally produced in forthcoming experiments. The symmetry breaking…
This paper includes two main parts. In the first part, we present generalized gauge models based on SU(3)_C x SU(4)_L x U(1)_X (3-4-1) gauge group with arbitrary electric charge of leptons. The mixing matrix of neutral gauge bosons is…
We analyze new physics contributions to $e^+e^-\to W^+W^-$ at the TeV energy scale, employing an effective field theory framework. A complete basis of next-to-leading order operators in the standard model effective Lagrangian is used, both…
Testing the stability of the electroweak vacuum in any extension of the Standard Model Higgs sector is of great importance to verify the consistency of the theory. Multi-scalar extensions as the Minimal Supersymmetric Standard Model…
We examine the Standard Model under the electroweak symmetry group $U_{EW}(2)$ subject to the Lie algebra condition $\mathfrak{u}_{EW}(2)\not\cong \mathfrak{su}_{I}(2)\oplus \mathfrak{u}_{Y}(1)$. Physically, the condition ensures that all…
Severe constraints on parameters of the minimal supersymmetric standard model follow from a dynamical electroweak symmetry breaking mechanism dominated by top and stop loops. In particular, the lightest Higgs boson mass is expected to be…
We consider a non-linear realization of the electroweak symmetry-breaking pattern $SU(2)_L\times SU(2)_R/SU(2)_{L+R}$ to construct a low-energy effective theory, later extended by the inclusion of heavy new-physics resonances. After…
In the framework of the effective field theory method, we use the experimental data and the perturbative unitarity bounds to determine the values and uncertainty of all the 11 chiral coefficients ($\al_i, i=0, ..., 10$) of the standard…
We discuss the minimal supersymmetric $U(1)_{B-L}\times U(1)_R$ extension of the standard model. Gauge couplings unify as in the MSSM, even if the scale of $U(1)_{B-L}\times U(1)_R$ breaking is as low as order TeV and the model can be…
Motivated by the recent precision measurements of the W boson mass and top quark mass, we test the Littlest Higgs model by confronting the prediction of M_W with the current and prospective measurements of M_W and M_t as well as through the…
The standard model for electroweak interactions uses the concepts of weak hypercharge and local gauge invariance of the Lagrangian density under the gauge group SU(2) x U(1). Taylor has remarked that U(1), being a multiply-connected group,…
A modified formulation of the Electroweak Model with 3-dimensional spherical geometry in the target space is suggested. The {\it free} Lagrangian in the spherical field space along with the standard gauge field Lagrangian form the full…
Little Higgs models are an interesting extension of the Standard Model at the TeV scale. They provide a simple and attractive mechanism of electroweak symmetry breaking. We review one of the simplest models of this class, the Littlest Higgs…
The Standard Model Effective Field Theory (SMEFT) and the Low Energy Effective Field Theory (LEFT) can be extended by adding additional spin 0, 1/2 and 1 dark matter particles which are singlets under the Standard Model (SM) gauge group. We…
We propose a minimal supersymmetric Twin Higgs model that can accommodate tuning of the electroweak scale for heavy stops better than 10% with high mediation scales of supersymmetry breaking. A crucial ingredient of this model is a new…
The Standard Model of electroweak interactions has one scalar doublet. The minimal extension of this sector is effected by adding a neutral, singlet scalar field. Depending on whether the singlet field has a non-zero vacuum expectation…
We consider an extension of the standard electroweak theory with gauge group $SU(2)_L \times SU(2)_R \times U(1)_{\tilde{Y}}$, where the gauge bosons of the extra $SU(2)_R$ factor do not couple to ordinary fermions. We show that precision…
One of the assumptions of simplified models is that there are a few new particles and interactions accessible at the LHC and all other new particles are heavy and decoupled. The effective field theory (EFT) method provides a consistent…