Related papers: Confronting Electroweak Fine-tuning with No-Scale …
Electroweak observables are highly sensitive to the loop corrections. Therefore, a proper gauge-fixing mechanism is always needed to define the propagators which are involved in Feynman loop amplitude. With this spirit we compute…
The recent discovery of a 125 GeV Higgs-like resonance at LHC, coupled with the lack of evidence for weak scale supersymmetry (SUSY), have severely constrained SUSY models such as mSUGRA/CMSSM. As LHC probes deeper into SUSY model parameter…
Supersymmetric gauge theories, in higher dimensions compactified in an orbifold, give a natural framework to unify the gauge bosons, Higgs fields and even the matter fields in a single multiplet of the unifying gauge symmetry. The extra…
The alternative renormalizable minimal $SO(10)$ model is composed of the Yukawa couplings with $\textbf{10} \oplus \textbf{120}$ Higgs fields, whereas the right-handed (RH) neutrino Majorana masses are generated via the Witten mechanism.…
We present a non-perturbative model of Gauge-Higgs Unification. We consider a five-dimensional pure SU(2) gauge theory with orbifold boundary conditions along the fifth dimension, such that the symmetry is reduced to U(1) at the fixed…
Numerical simulations are performed on different lattice sizes of chiral U(1) and SU(2) scalar-fermion models with explicit mirror pairs of fermions in the broken symmetry phase. Relevance of these models to the electroweak theory is…
We analyze models of electroweak symmetry breaking in warped 5-dimensional space with gauge bosons and fermions in the bulk. The Higgs boson is identified with the 5th component of a gauge field. We dynamically generate the Higgs potential…
For the case of the MSSM and the most general form of the NMSSM (GNMSSM) we determine the reduction in the fine tuning that follows from allowing gaugino masses to be non-degenerate at the unification scale, taking account of the LHC8…
Relationships between gauge, conformal and discrete symmetries in particle physics are analysed. We study also the effect of the electroweak mixing on the cancellation of SU(2) anomalous actions. It is shown that the relation theta_{W} =…
We study models of supersymmetric grand unification based on the SO(10) gauge group. We investigate scenarios of non-universal gaugino masses including models containing a mixture of two representations of hidden sector chiral superfields.…
We consider the generation of fermion masses in an emergent model of electroweak symmetry breaking with composite $W,Z$ gauge bosons. A universal bulk fermion profile in a warped extra dimension is used for all fermion flavors. Electroweak…
The Standard Model global fit to precision data is excellent. The Minimal Supersymmetric Standard Model can also fit the data well, though not as well as the Standard Model. At best, supersymmetric contributions either decouple or only…
I consider models with non-universal gaugino masses at the gauge coupling unification scale, taking into account the Higgs boson discovery. Viable regions of parameter space are mapped and studied in the case of non-universality following…
We explore unification and natural supersymmetry in a five dimensional extension of the standard model in which the extra dimension may be large, of the order of 1-10 TeV. Power law running generates a TeV scale A_ term allowing for the…
Inspired by the string landscape and the unified gauge coupling relation in the F-theory Grand Unified Theories (GUTs) and GUTs with suitable high-dimensional operators, we study the canonical gauge coupling unification and Higgs boson mass…
The main purpose of this thesis is to discuss the impact of electroweak precision measurements on the present knowledge of particle physics, both in the framework of the Standard Model and of its most straightforward extensions. In Chapter…
Electroweak second order shifts of muonium ($\mu^+e^-$ bound state) energy levels are calculated for the first time. Calculation starts from on-shell one-loop elastic $\mu^+ e^-$ scattering amplitudes in the center of mass frame, proceed to…
Unlike the Standard Model (SM), supersymmetric models stabilize the electroweak (EW) scale $v$ at the quantum level and {\it predict} that $v$ is a function of the TeV-valued SUSY parameters ($\gamma_\alpha$) of the UV Lagrangian. We show…
We investigate the status of predictive fermion mass ansatzes which make use of the grand unification scale conditions $m_e=m_d/3$, $m_\mu =3m_s$, and $\mid V_{cb}\mid =\sqrt{m_{c}/m_{t}}$ in non-supersymmetric SO(10) grand unification. The…
An electroweak (EW) model has been investigated (Moffat) in which the energy $E < \mu=\sqrt{\lambda}M_W$, where $\lambda$ is a gauge parameter and $M_W$ is the $W$ boson mass. For large enough $\lambda$ the scalar boson mass…