Related papers: Vacuum Stability as a Guide for Model Building
We consider a generic type of leptogenesis model which can successfully produce the correct value of the observed baryon number to entropy ratio. The main feature of this model is that it is a simple TeV scale model, a scale accessible in…
We consider vector-like quarks in a leptophobic 221 model characterized by the gauge group $SU(2)_L\times SU(2)_2 \times U(1)_X$, where the $SU(2)_2$ is leptophobic in nature. We discuss about the pattern of mixing between Standard Model…
We explore a novel mechanism to restrict TeV-scale leptoquark interactions and render the proton exactly stable to all orders in the effective field theory expansion. A scalar condensate breaks a lepton-flavoured $\mathrm{U}(1)_X$ gauge…
A minimal non-thermal dark matter model that can explain both the existence of dark matter and the baryon asymmetry in the universe is studied. It requires two color-triplet, iso-singlet scalars with $\mathcal{O}$(TeV) masses and a singlet…
The Standard Model (SM) Higgs potential is likely to be metastable, in which case Higgs Inflation requires an extension of the SM to sufficiently stabilise the Higgs potential. Here we consider stabilisation by adding $n_{Q} \leq 3$…
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.…
Quarks, leptons and heavy vector bosons are suggested to be composed of stable spin-1/2 preons, existing in three flavours, combined according to simple rules. Straightforward consequences of an SU(3) preon-flavour symmetry are the…
The origin of quark and lepton masses is one of the outstanding problems of physics. As the experimental data becomes more and more accurate, testing theories of fermion masses requires greater care. In this talk we discuss a theoretical…
We present a new class of Dark Matter (DM) models wherein the Standard Model (SM) is extended with a new $SU(2)_D$ dark gauge sector. In this framework the stability of DM is provided by the conservation of a $U(1)$ global symmetry, which…
In this work, we continue our exploration of TeV-scale vector-like fermion signatures inspired by a Grand Unification scenario based on the trinification gauge group. A particular focus is given to pair-production topologies of vector-like…
In extending the minimal standard model of quarks and leptons to include supersymmetry, the conservation of baryon and lepton numbers is no longer automatic. I show how the latter may be achieved with a new U(1) gauge symmetry and new…
In 2012 the discovery of the Higgs boson by the ATLAS and CMS collaborations set a milestone in particle physics by finding the missing piece of the Standard Model. Nonetheless some questions are still open: the origin of the mass of the…
An approach to the model-independent searching for the Z' gauge boson as a virtual state in scattering processes is developed. It accounts for as a basic requirement the renormalizability of underlying unspecified in other respects model.…
We consider the framework of flavoured leptoquarks, in models with scalar or vector leptoquarks, and look for constraints to the parameter space of these models. Using primarily direct searches at the Large Hadron Collider (LHC) and…
We consider the mechanism of thermal leptogenesis at the TeV scale in the context of an extension of the Standard Model with 4 generations and the inclusion of four right-handed Majorana neutrinos. We obtain a value for the baryon asymmetry…
In this paper I review the possibility of TeV scale strings that may be detectable by the Large Hadron Collider (LHC). This possibility was investigated extensively in a series of phenomenological papers during 1984-1985 in connection with…
We study a model of vector dark matter with the complex scalar Higgs portal. Renormalisation group equations at the 2-loop level are used to analyse perturbativity and stability of the vacuum. We impose experimental and theoretical…
Though some LHC searches for new physics exceed the TeV scale, there may be discoveries waiting to be made at much lower masses. We outline a simple quirk model, motivated by models that address the hierarchy problem through neutral…
We explore an extension of the Standard Model by an additional U (1) gauge group and a complex scalar Higgs portal. As the scalar is charged under this gauge factor this simple model supplies a vector dark matter candidate satisfying the…
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…