Related papers: RGE and the Fine-Tuning Problem
In this thesis a simple extension of the Standard Model has been investigated. The Standard Model gauge group has been extended by an additional $U(1)_X$ group. The model introduces a new Higgs particle as well as three particles (a gauge…
We explore the phenomenological consequences of a model with an extended scalar sector, incorporating strongly coupled inert Higgs doublets. The model introduces three Higgs doublets: one that interacts with the $SU(2)$ symmetry of the…
The use of the mass term as a gauge fixing term has been studied by Zwanziger, Parrinello and Jona-Lasinio, which is related to the non-linear gauge $A_{\mu}^{2}=\lambda$ of Dirac and Nambu in the large mass limit. We have recently shown…
We study how the recent ATLAS and CMS Higgs mass bounds affect the renormalization group running of the physical parameters in universal extra dimensions. Using the running of the Higgs self-coupling constant, we derive bounds on the cutoff…
The Two-Higgs Doublet Model (2HDM) is one of the most popular and natural extensions of the Higgs sector; but it has two potential fine-tuning problems, related to the electroweak (EW) breaking and the requirement of alignment with the SM…
The review is devoted to consideration of possible observational consequences of modified gravity theories, suggested for explanation of the contemporary accelerated expansion of the universe. The major attention is paid to F(R)-models. It…
The minimal supersymmetry standard model (MSSM) extended with vector-like theories have long been discussed. If we extend the vector-like MSSM theory into NMSSM and let the vector-like particles couple with the singlet (S), we find out a…
We consider a conformal model involving two real scalar fields in which the conformal symmetry is broken by a soft mechanism and is not anomalous. One of these scalar fields is representative of the standard model Higgs. The model predicts…
A recent ATLAS search for diboson resonances and a CMS search for $eejj$ resonances which both show excesses with significance around 3 sigma have generated interest in $SU(2)_R$ gauge extensions of the Standard Model with a $W'$ mass…
Discarding the prejudice about fine tuning, we propose a novel and efficient approach to identify relevant regions of fundamental parameter space in supersymmetric models with some amount of fine tuning. The essential idea is the mapping of…
It is shown that fine-tuning of the Higgs parameters stronger than a few % is required at the best in the models with gauge mediated supersymmetry breaking. With the aim of solving this problem, we consider a new type of models in which the…
We review recent developments and results in testing general relativity (GR) at cosmological scales. The subject has witnessed rapid growth during the last two decades with the aim of addressing the question of cosmic acceleration and the…
This article reviews the theoretical constraints on the scalar potential of a general extension of the Standard Model that encompasses a $SU(3)_c\times SU(3)_L\times U(1)_X$ gauge symmetry. In this respect, the boundedness-from-below is…
Grand gauge-Higgs unification of five dimensional SU(6) gauge theory on an orbifold $S^1 / Z_2$ with localized gauge kinetic terms is discussed. The Standard model (SM) fermions on the boundaries and some massive bulk fermions coupling to…
We show that the addition of real scalars (gauge singlets) to the Standard Model can both ameliorate the little hierarchy problem and provide realistic Dark Matter candidates. To this end, the coupling of the new scalars to the standard…
The solution of a fine tuning problem is one of the principal motivations of Supersymmetry. However experimental constraints indicate that many Supersymmetric models are also fine tuned (although to a much lesser extent). We review the…
We investigate how the Next-Two-Higgs Doublet Model extension (N2HDM) should look if we are to address the naturalness problem using dimensional regularization. In such a model, new Higgs states are predicted, namely: three CP-even…
Strongly-coupled gauge theories are an important ingredient in the construction of many extensions of the standard model, particularly for models of electroweak symmetry breaking in which the Higgs boson is a composite object. There is a…
In this paper we explore models in which we add a singlet scalar Higgs to the Standard Model. All of these models explain the origin of the mass hierarchy amongst the fermion masses and mixing angles. We discuss 24 different variations on…
In General Gauge Mediation (GGM) all MSSM soft sfermion masses at a high scale M_mess can be parameterised by three a priori independent scales \Lambda_{S;1,2,3}(M_mess). (Similarly the gaugino masses are given by…