Related papers: A new (string motivated) approach to the little hi…
We argue that supersymmetry breaking by gaugino condensation in the strongly coupled heterotic string can be described by an analogue of Scherk-Schwarz compactification on the eleventh dimension in M-theory. The M-theory scale is identified…
We investigate the impact of TeV-scale matter belonging to complete vectorlike multiplets of unified groups on the lightest Higgs boson in the MSSM. We find that consistent with perturbative unification and electroweak precision data the…
After the discovery of SM-like Higgs with $m_{h}=125$ GeV, it is increasingly urgent to explore a solution to the hierarchy problem. In the context of MSSM from gauge-mediated SUSY breaking, the lower bound on gluino mass suggests that the…
The Minimal Supersymmetric Standard Model (MSSM) can include two soft breaking terms which are often neglected: a non-analytic scalar trilinear coupling and a Higgsino bilinear term. A set of high-scale boundary conditions consistent with…
Motivated by the coupling unification problem, we propose a novel extension of the Minimal Supersymmetric Standard Model. One of the predictions of this extension is existence of new states neutral under SU(3)_c X SU(2)_w but charged under…
We propose an extended version of the standard model, in which neutrino oscillation, dark matter, and baryon asymmetry of the Universe can be simultaneously explained by the TeV-scale physics without assuming unnatural hierarchy among the…
A mass Hierarchy of magnitude O(10^16) GeV separates the gravitational and electroweak interactions. Traditional proposed resolutions of this anomaly have included supersymmetric theories (most notably, the MSSM and ESSM) and string theory.…
A keV-scale gravitino arsing from a minimal supersymmetric (SUSY) Standard Model (MSSM) is an interesting possibility since the small scale problems that $\Lambda$CDM model encounters in the modern cosmology could be alleviated with the…
We show that when the supersymmetric SU(5) model is extended to explain small neutrino masses by the type III seesaw mechanism, the new {\bf 24}-dimensional fields needed for the purpose can act as messengers for transmitting SUSY breaking…
I describe, from the bottom up, a sequence of natural effective field theories. Below a TeV we have the minimal standard model with a light Higgs, and an extra neutral scalar. In the 1-10 TeV region these scalars are part of a multiplet of…
We study an extension of the MSSM which includes both new SU(2) triplets with hypercharge $\pm 1$ and a SM gauge singlet (a la NMSSM) which are coupled to each other. We are motivated by the little hierarchy problem, as well as by the $\mu$…
We derive cosmological constraints on the masses of generic scalar fields which decay only through gravitationally suppressed interactions into unstable gravitinos and ordinary particles in the supersymmetric standard model. For the…
We analyse the predictions of both Higgs and top masses in a generic MSSM satisfying gauge-coupling unification, radiative electroweak symmetry breaking, with a natural (non-splitted) spectrum of soft-breaking terms, and an arbitrary…
We study the next-to-minimal supersymmetric standard model (NMSSM) with the TeV scale mirage mediation, which is known as a solution for the little hierarchy problem in supersymmetry. Our previous study showed that 125 GeV Higgs boson is…
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…
Neutrino mass generation may affect the basic structure of the electroweak symmetry breaking sector. We consider a broad class of elementary particle theories where neutrinos get mass at a low mass scale. We show how these can be made…
We study the C and P even WW\gamma and WWZ trilinear gauge boson vertices (TGV's), in the context of the MSSM assuming that the external W's are on their mass shell. We find that for energies less than 200 GeV squark and slepton…
Little Higgs theories are an attempt to address the little hierarchy problem, i.e., the tension between the naturalness of the electroweak scale and the precision measurements showing no evidence for new physics up to 5-10 TeV. In little…
The predictions for the Higgs mass in extensions of the Minimal Supersymmetric Standard Model are discussed. We propose a simple theory where the Higgs mass is modified at tree-level and one can achieve a mass around 125 GeV without…
With the Higgs boson mass around 125 GeV and the LHC supersymmetry search constraints, we revisit a three-family Pati-Salam model from intersecting D6-branes in Type IIA string theory on the $\mathbf{T^6/(\Z_2 \times \Z_2)}$ orientifold…