Related papers: Evading the Few TeV Perturbative Limit in 3-3-1 Mo…
The electroweak phase transition (EWPT) is considered in the framework of 3-3-1-1 model for Dark Matter. The phase structure within three or two periods is approximated for the theory with many vacuum expectation values (VEVs) at TeV and…
We re-examine the problem of simultaneously describing in a consistent way all radiative and leptonic decays of light mesons (V -> P gamma, P -> V gamma, P -> gamma gamma, V -> e^+ e^-). For this purpose, we rely on the Hidden Local…
We explore a class of simplified extensions to the Standard Model containing a complex singlet scalar as a dark matter candidate accompanied by a vector-like lepton as a mediator, both charged under a new $Z_3$ symmetry. In its simplest…
The pursuit of discovery in particle physics has always required study at the highest possible energies. Multi-TeV muon colliders, which have important advantages, offer unprecedented potential for investigating new physics beyond the…
We construct a comprehensive list of non-supersymmetric standard model extensions with a low-scale LR-symmetric intermediate stage that may be obtained as simple low-energy effective theories within a class of renormalizable $SO(10)$ GUTs.…
We propose the minimal and renormalizable non-supersymmetric top SU(5) models where the $SU(5)\times SU(3)'_C \times SU(2)'_L \times U(1)'_Y$ gauge symmetry is broken down to the Standard Model (SM) gauge symmetry at the TeV scale. The…
We discuss the potential of a $0.5\hskip 2pt TeV$ linear collider to explore manifestations of extended (or alternative) electroweak models of current interest, through measurements of the reaction $e^+e^-\to W^+W^-$ with both initial and…
We consider $SU(3)_{C}\times SU(2)_{AL}\times SU(2)_{BL}\times U(1)_{Y}$ as the low-energy subgroup of supersymmetric $SU(3)^{6}$ unification. This may imply small deviations from quark-lepton universality at the TeV scale, as allowed by…
We calculate the tree-level electroweak precision constraints on a wide class of little Higgs models including: variations of the Littlest Higgs SU(5)/SO(5), SU(6)/Sp(6), and SU(4)^4/SU(3)^4. By performing a global fit to the precision data…
We explore the one-loop electroweak radiative corrections in the minimal $SU(5)$ and the no-scale flipped $SU(5)$ supergravity models via explicit calculation of vacuum polarization contributions to the $\epsilon_{1,2,3}$ parameters.…
If supersymmetry (SUSY) is not for stabilizing the electroweak energy scale, what is it used for in particle physics? We propose that it is for flavor problems. A cyclic family symmetry is introduced. Under the family symmetry, only the…
We present a brief review of recent attempts to construct effective theories to describe the breaking of the electroweak symmetry in extensions of the Standard Model with new strongly interacting dynamics around the TeV scale. Particular…
In this work we introduce CPT-odd non-minimal Lorentz-symmetry violating couplings to the electroweak sector modifying the interaction between leptons and gauge bosons. The vertex rules allow us to calculate tree-level processes modified by…
The discrepancies between the measurements of rare (semi-)leptonic $B$ decays and the corresponding Standard Model predictions point convincingly towards the existence of new physics for which a heavy neutral gauge boson ($Z^\prime$) is a…
The discovery of neutrino masses has raised the importance of studies in the context of neutrinoless double beta decay, which constitutes a landmark for lepton number violation. The standard interpretation is that the light massive…
In these lectures, I review the status of the electroweak sector of the Standard Model, with an emphasis on the importance of radiative corrections and searches for the Standard Model Higgs boson. A discussion of the special role of the TeV…
We recently showed that a new gauge boson $\gamma_B$ coupling only to baryon number is phenomenologically allowed, even if $m_B<m_Z$ and $\alpha_B \approx 0.2$. In our previous work we assumed that kinetic mixing between the baryon number…
Some new physics beyond the Standard Model of particle physics, like Supersymmetry, Extra-dimensions etc., and their effect on the nature of different standard model phenomena are explored in this thesis. We discuss the power law scaling of…
Extensions of the Standard Model which involve a new scale, $\Lambda$, may, for energies sufficiently small compared to this new scale, be expressed in terms of operators with energy dimension greater than four. The coefficients of just…
The modification of the Electroweak Model with 3-dimensional spherical geometry in the matter fields space is suggested. The Lagrangian of this model is given by the sum of the {\it free} (without any potential term) matter fields…