Related papers: The Weak Mixing Angle From TeV Scale Quark-Lepton …
We study minimal 5-dimensional extensions of the Standard Model, in which all or only some of the SU(2)$_L$ and U(1)$_Y$ gauge fields and Higgs bosons propagate in the fifth compact dimension. In all the 5-dimensional settings, the fermions…
Within low scale theories traditional see-saw and scalar triplet mechanisms, for neutrino mass suppression, do not work out anymore and for realistic model building some new ideas are needed. In this paper we suggest mechanism, different…
Some low-energy manifestations of a minimal extension of the Standard Model based on the quark-lepton $SU(4)_V \otimes SU(2)_L \otimes G_R$ symmetry of the Pati-Salam type are analysed. Given this symmetry a new type of mixing in the…
There is a unique $SU(4) \otimes SU(2)_L \otimes SU(2)_R$ gauge model which allows quarks and leptons to be unified at the TeV scale. It is already known that the neutrino masses arise radiatively in the model and are naturally light. We…
There is a unique $\hbox{SU(4)}\otimes\hbox{SU(2)}_L \otimes \hbox{SU(2)}_R$ gauge model which allows quarks and leptons to be unified at the TeV scale -- thereby making the model testable and avoiding the gauge hierarchy problem. In its…
We reconsider the constraints on Universal Extra Dimensions (UED) models arising from precision electroweak data. We take into account the subleading contributions from new physics (expressed in terms of the X,Y ... variables), as well as…
In this paper, we propose to compactify a single large extra dimension (LED) on a star/rose graph with a large number of identical leaves/petals. The 5D Planck scale can be chosen to be $\Lambda_P^{(5)} \sim \mathcal{O}(1)$ TeV which can…
Simple models are proposed where the baryon and lepton number are gauged and spontaneously broken near the weak scale. The models use a fourth generation that is vector-like with respect to the strong, weak and electromagnetic interactions…
In this talk, we summarize our recent proposal for lowering the scale of grand unification to the TeV range though the appearance of extra spacetime dimensions. Particular emphasis is placed on the perturbativity and predictivity of our…
A secluded U(1) sector with weak admixture to photons, O(10^{-2}-10^{-3}), and the scale of the breaking below 1 GeV represents a natural yet poorly constrained extension of the Standard Model. We analyze g-2 of muons and electrons together…
We study the phenomenology of a 5D $SU(3)_W$ model on a $S_1/(Z_2\times Z'_2)$ orbifold in which the minimal scalar sector plays an essential role of radiatively generating neutrino Majorana masses without the benefits of right-handed…
We investigate the renormalization group evolution of masses and mixing angles of Majorana neutrinos under the `High Scale Mixing Unification' hypothesis. Assuming the unification of quark-lepton mixing angles at a high scale, we show that…
We explore the possibility of unification of gauge couplings near the Planck scale in models of extended technicolor. We observe that models of the form G X SU(3)_c X SU(2)_L X U(1)_Y cannot be realized, due to the presence of massless…
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…
The recent experimental measurements of the solar neutrino mixing angle $\theta_{sol}$ and the Cabibbo mixing angle $\theta_C$ reveal a surprising relation, $ \theta_{sol}+\theta_C \simeq \frac{\pi}{4}$. We note that the lepton mixing…
A simple Pati-Salam SU(4) model with a low symmetry breaking scale of about 1000 TeV is presented. The analysis concentrates on calculating radiative corrections to tree-level mass relations for third generation fermions. The tree-level…
Unification ideas motivate the formulation of field equations on an extended spin space. Demanding that the Poincare symmetry be maintained, one derives scalar symmetries that are associated with flavor and gauge groups. Boson and fermion…
The recently proposed dark left-right gauge model, with Z' and W_R bosons at the TeV scale, is shown to have a simple supersymmetric extension which is unifiable. Its one-loop gauge-coupling renormalization-group equations are shown to have…
In models with a U(1) gauge extension beyond the Standard Model, one can derive sum rules for the couplings of the theory that are a consequence of tree-level unitarity. In this paper, we provide a comprehensive list of coupling sum rules…
One of the much-debated novel features of theories with extra dimensions is the presence of power-like loop corrections to gauge coupling unification, which have the potential of allowing a significant reduction of the unification scale. A…