Related papers: Hexagonal SU(3) Unification and its Manifestation …
We study the indirect effects of new physics on the phenomenology of the "Higgs-like" particle. Assuming that the recently observed state belongs to a light electroweak doublet scalar and that the SU(2)_L x U(1)_Y symmetry is linearly…
Recent string constructions with intersecting D6 and D5 brane models succeeded in predicting in the low energy limit a symmetry group and a fermionic spectrum similar to that of the SM. In such constructions additional U(1) fields are a…
We investigate models of supersymmetric grand unification based on the gauge group SU(5). We consider models with non-universal gaugino masses and confront them with low energy constraints, including the Higgs boson mass and the Dark Matter…
The vector boson dark matter particles which stem from some broken gauge symmetries usually requires some unbroken symmetries to keep themselves stable. In the previous literature, some simplest cases have been discussed, in which the…
The Standard Model for electroweak interactions derives four vector gauge boson from an SU(2)xU(1) symmetry. A doublet of complex scalar (Higgs) bosons is added to generate masses by spontaneous symmetry breaking. Both, the four vector…
We study meson decays mediated by the heavy gauge bosons of the Pati-Salam model of quark-lepton unification. We consider the scenarios in which the tau lepton is associated with the third, second, and first generation of quarks. The most…
The lack of evidence for low energy supersymmetry at the LHC implies a supersymmetry scale in excess a TeV. While this is consistent (and even helpful) with a Higgs boson mass at $\approx$ 125 GeV, simple supersymmetric models with scalar…
Precision gauge coupling unification is one of the primary quantitative successes of low energy or split supersymmetry. Preserving this success puts severe restrictions on possible matter and gauge sectors that might appear at…
We show that some models with $SU(3)_C\otimes SU(3)_L\otimes U(1)_X$ gauge symmetry can be realized at the electroweak scale and that this is a consequence of an approximate global $SU(2)_{L+R}$ symmetry. This symmetry implies a condition…
We consider supersymmetric unification based on the gauge symmetry SU(3)_C\times SU(3)_L\times SU(3)_R supplemented by an anomalous U(1)_A gauge symmetry. Realistic fermion masses and mixings are realized, including large mixings in the…
We study the path from the string scale physics to the low-energy physics in the $SU(6) \times SU(2)_R$ string-inspired model with the flavor symmetry ${\bf Z}_M \times {\bf Z}_N \times \tilde{D}_4$. The flavor symmetry controls the mass…
The quartic gauge boson couplings in the ${SU(3)}_C \otimes {SU(3)}_L \otimes {U(1)}_N$ models are presented. We find that the couplings of four {\it differrent} gauge bosons may have unusual Lorentz structure and the couplings sastify the…
The gauge symmetry $SU(5) \times U(1)_\chi$ is the unique maximal subgroup of SO(10) which retains manifest unification at $M_{GUT}$ of the Standard Model gauge couplings, especially if low scale supersymmetry is present. The spontaneous…
The new SM-like Higgs boson discovered recently at the LHC, with mass $m_h \simeq$ 125 GeV, as well as the direct LHC bounds on the mass of superpartners, which are entering into the TeV range, suggest that the minimal surviving…
A complete 5-dimensional SU(5) unified theory is constructed which, on compactification on the orbifold with two different Z_2's (Z_2 and Z_2'), yields the minimal supersymmetric standard model. The orbifold accomplishes SU(5) gauge…
The gauge symmetry breaking in 3-3-1 models can be implemented dynamically because at the scale of a few TeVs the U(1)_X coupling constant becomes strong. The exotic quark T introduced in the model will form a condensate breaking SU(3)_L x…
We show that four-dimensional N=2 supersymmetric SU(n) gauge theory for n>2 necessarily contains vacua with mutually non-local massless dyons, using only analyticity of the effective action and the weak coupling limit of the moduli space of…
In a model in which leptons, quarks, and the recently introduced hyperquarks are built up from two fundamental spin 1/2 preons, the standard model weak gauge bosons emerge as preon bound states. In addition, the model predicts a host of new…
We show that the idea of Gauge-Higgs unification(GHU) can be rescued from the constraint of weak mixing angle by introducing localized brane kinetic terms in higher dimensional GHU models with bulk and simple gauge groups. We find that…
A phenomenological analysis of the three-family model based on the local gauge group $SU(3)_c\otimes SU(3)_L\otimes U(1)_X$ with exotic charged leptons, is carried out. Instead of using the minimal scalar sector able to break the symmetry…