Related papers: Naturalness and a light $Z'$
In theories in which SUSY is broken on a brane separated from the MSSM matter fields, supersymmetry breaking is naturally mediated in a variety of ways. Absent other light fields in the theory, gravity will mediate supersymmetry breaking…
In this talk, I shall address two key issues related to electroweak symmetry breaking. First, how fine-tuned different models are that trigger this phenomenon? Second, even if a light Higgs boson exists, does it have to be necessarily…
The $W$ boson mass recently reported by the CDF collaboration shows a deviation from the standard model prediction with an excess at $7\sigma$ level. We investigate two simple extensions of the standard model with an extra $U(1)$ dark…
In this paper we increase the MSSM tree level higgs mass bound to a value that is naturally larger than the LEP-II search constraint by adding to the superpotential a $\lambda S H_{u}H_{d}$ term, as in the NMSSM, and UV completing with new…
We explore, in the MSSM context, an extension of the Anomaly Mediated Supersymmetry Breaking solution for the soft scalar masses that is possible if the underlying theory has a gauged R-symmetry. The slepton mass problem characteristic of…
The minimal supersymmetric standard model (MSSM), is perhaps the leading candidate for new physics beyond the standard model, but it encounters difficulties with string gauge unification and in addition does not shed any light on the…
The extensions of the minimal supersymmetric model (MSSM), driving mainly from the need to solve the \mu problem, involve novel matter species and gauge groups. These extended MSSM models can be searched for at the LHC via the effects of…
We propose a mirror model for ordinary and dark matter that assumes a new SU(3) gauge group of transformations, as a natural extension of the Standard Model (SM). A close study of big bang nucleosynthesis, baryon asymmetries, cosmic…
We propose a simple gauge extension of the minimal supersymmetric standard model (MSSM), where the fine tuning in the Higgs mass parameters is highly reduced. The Higgs boson is insensitive to high energies because of supersymmetry and also…
We consider an anomaly free extension of the standard model gauge group $G_{\rm SM}$ by an abelian group to $G_{\rm SM}\otimes U(1)_Z$. The condition of anomaly cancellation is known to fix the $Z$-charges of the particles, but two. We fix…
A brief review is made of some of the experimental signatures that may be associated to a certain class of extensions of the standard model. The material of these lectures is divided into two sections. After briefly sketching the present…
We analyze the Minimal Supersymmetric extension of the Standard Model that we have after the discovery of the Higgs boson at the LHC, the hMSSM (habemus MSSM?), i.e. a model in which the lighter $h$ boson has a mass of approximately 125 GeV…
The discovery of a standard model (SM)-like Higgs boson with a relatively heavy mass $m_h$ and hints of di-photon excess has deep implication to supersymmetric standard models (SSMs). We consider the SSM extended with hypercharge $\pm1$…
We consider the SM extension with additional light real singlet scalar, right-handed neutrino and nonrenormalizable Yukawa interaction for the first two generations. We show that the proposed model can explain the observed $(g - 2)$ muon…
At present, the Standard Model (SM) agrees with almost all collider data. Yet, three finetuning issues -- the Higgs mass problem, the strong CP problem and the cosmological constant problem -- all call for new physics. The most plausible…
Supersymmetry is one of the most plausible and theoretically motivated frameworks for extending the Standard Model. However, any supersymmetry in Nature must be a broken symmetry. Dynamical supersymmetry breaking (DSB) is an attractive idea…
The Principle of Naturalness of small parameters of a theory is reviewed. While quantum field theories constructed from gauge fields and fermions only are natural, those containing elementary scalar fields are not. In particular the Higgs…
The particle spectrum of the supersymmetric extension of the standard model with a gauge singlet is studied. Soft supersymmetry breaking terms are explicitly chosen to be non-universal according to orbifold string theory. they depend on…
In this paper, we explore conditions for focus point in the high-scale supersymmetry with the weak-scale gaugino masses. In this context the tension between the naturalness and LHC 2013 data about supersymmetry as well as the cold dark…
Light extra U(1) gauge bosons, so called hidden photons, which reside in a hidden sector have attracted much attention since they are a well motivated feature of many scenarios beyond the Standard Model and furthermore could mediate the…