Related papers: The Fermion Mass Problem and the Anti-Grand Unific…
From considerations of the number of matrix elements of different orders of magnitude in the quark and charged lepton mass matrices, we suggest that the underlying gauge group responsible for the spectrum should have several---actually of…
The quark-lepton mass problem and the ideas of mass protection are reviewed. The Multiple Point Principle is introduced and used within the Standard Model to predict the top quark and Higgs particle masses. We discuss the lightest family…
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…
We look for minimal chiral sets of fermions beyond the standard model that are anomaly free and, simultaneously, vectorlike particles with respect to colour SU(3) and electromagnetic U(1). We then study whether the addition of such…
The natural grand unified theories solve various problems of the supersymmetric grand unified theory and give realistic quark and lepton mass matrices under the natural assumption that all terms allowed by the symmetry are introduced with…
A fermion mass matrix ansatz is proposed in the context of Grand Unified Supersymmetric Theories (GUTs). The fermion mass matrices are evolved down to the electroweak scale by solving the renormalization group equations for the gauge and…
The logarithmic running of the gauge couplings alpha_1, alpha_2 and alpha_3, indicates that they may unify at some scale M_GUT ~ 10^16. This is often taken to imply that the standard model gauge group is embedded into some larger simple…
We discuss a supersymmetric unified model based on a product gauge group SU(5)\times SU(5)\times SU(5), where the gauge symmetry breaking is achieved without the adjoint or higher-dimensional Higgs field, and the doublet-triplet splitting…
We present a simple model for fermion mass matrices and quark mixing in the context of supersymmetric grand unified theories and show its agreement with experiment. Our model realizes the GUT mass relations $m_d=3m_e$, $m_s= m_\mu/3$,…
We present a discussion of the neutrino mass problem in the anti-grand unification theory based on three family replicated copies of the Standard Model gauge group (SMG). We consider two versions of the theory, with and without right-handed…
We discuss gauge coupling unification in models with additional 1 to 4 complete vector-like families, and derive simple rules for masses of vector-like fermions required for exact gauge coupling unification. These mass rules and the…
The quark-lepton mass problem and the ideas of mass protection are reviewed. The hierarchy problem and suggestions for its resolution, including Little Higgs models, are discussed. The Multiple Point Principle is introduced and used within…
Imposing the constraint that the Standard Model effective Higgs potential should have two degenerate minima ( vacua), one of which should be - order of magnitudewise - at the Planck scale, leads to the top mass being 173 +/- 5 GeV and the…
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…
Using the current precision electroweak data, we look for the minimal particle content which is necessary to add to the standard model in order to have a complete unification of gauge couplings and gravity at the weakly coupled heterotic…
Grand Unified Theories (GUTs) usually predict wrong Standard Model (SM) fermion mass relation m_e/m_{\mu} = m_d/m_s toward low energies. To solve this problem, we consider the Generalized Minimal Supergravity (GmSUGRA) models, which are…
We calculate the $U(1)$ continuum gauge coupling using the values of action parameters at the multiple point in the phase diagram of a lattice gauge theory. The multiple point is where a maximum number of phases convene. We obtain for the…
The multiple point principle (MPP) is applied to the non--supersymmetric two-Higgs doublet extension of the Standard Model (SM). The existence of a large set of degenerate vacua at some high energy scale caused by the MPP results in a few…
Different approaches to the quark-lepton mass problem are reviewed. The infrared quasifixed point predictions for the top quark mass are discussed for the Standard Model and its minimal supersymmetric extension, with particular reference to…
We consider the multiple point principle (MPP) of the Standard Model (SM) with the scalar singlet Dark Matter (DM) and three heavy right-handed neutrinos at the scale where the beta function $\beta_{\lambda}$ of the effective Higgs self…