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Related papers: The Fermion Mass Problem and the Anti-Grand Unific…

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The fermion mass problem and the ideas of mass protection are briefly reviewed. The Fritzsch ansatz for the quark mass matrices and a recent variant, based on a lightest flavour mixing mechanism in which all the CKM mixing angles disappear…

High Energy Physics - Phenomenology · Physics 2007-05-23 C. D. Froggatt

The multiple point criticality principle is applied to the pure Standard Model (SM), with a desert up to the Planck scale. We are thereby led to impose the constraint that the effective Higgs potential should have two degenerate minima, one…

High Energy Physics - Phenomenology · Physics 2007-05-23 C. D. Froggatt , H. B. Nielsen , D. J. Smith

The fermion masses and mixing angles are fitted using only 3 free parameters in a non-supersymmetric extension of the Standard Model, with new approximately conserved chiral gauge quantum numbers broken by a set of Higgs fields. The…

High Energy Physics - Phenomenology · Physics 2009-10-30 C. D. Froggatt , M. Gibson , H. B. Nielsen , D. J. Smith

We describe a fit to the charged fermion mass hierarchy using the chiral quantum numbers of the maximal anti-grand unification group $SMG^3 \times U(1)_f$, where $SMG \equiv SU(3) \times SU(2) \times U(1)$. This fit suggests a set of Higgs…

High Energy Physics - Phenomenology · Physics 2007-05-23 C. D. Froggatt , H. B. Nielsen

We put forward a model, or rather a relatively broad class of models, beyond the Standard Model based on the two main assumptions: MPP) The coupling constants should be fixed such as to ensure that there be many ``vacuum states'', i.e.…

High Energy Physics - Phenomenology · Physics 2007-05-23 D. L. Bennett , C. D. Froggatt , H. B. Nielsen

We present an extension of the Standard Model (SM) without supersymmetry, which we use to calculate order of magnitude values for the elements of the mass matrices in the SM. In our model we can fit the 9 quark and lepton masses and 3…

High Energy Physics - Phenomenology · Physics 2009-10-28 C. D. Froggatt , H. B. Nielsen , D. J. Smith

We present two rather differently based predictions for the quark and lepton spectrum: One provides a rather successful fit to the mass suppressions---the well known fermion mass hierarchy---interpreted as due to most mass terms needing to…

High Energy Physics - Phenomenology · Physics 2009-10-30 C. D. Froggatt , H. B. Nielsen

This review is devoted to Anti-Grand Unification and to the Multiple Point Model solution of problems of the unification of gauge interactions. According to this model, near the Planck scale there exists a Multiple Critical Point (MCP),…

High Energy Physics - Theory · Physics 2007-05-23 L. Laperashvili

The fermion mass problem is briefly reviewed. The observed hierarchy of quark and charged lepton masses strongly suggests the existence of an approximately conserved chiral flavour symmetry beyond the Standard Model. It is argued that in…

High Energy Physics - Phenomenology · Physics 2007-05-23 C. D. Froggatt

We consider the application of the Multiple Point Criticality Principle to the Standard Model and its extension to the anti-grand gauge group $SMG^3 \otimes U(1)_f$ at the Planck scale. In particular we discuss the predictions for the fine…

High Energy Physics - Phenomenology · Physics 2007-05-23 D. L. Bennett , C. D. Froggatt , H. B. Nielsen

Grand gauge-Higgs unification of five dimensional $SU(6)$ gauge theory on an orbifold $S^1/Z_2$ is discussed. The Standard model (SM) fermions are introduced on one of the boundaries and some massive bulk fields are also introduced so that…

High Energy Physics - Phenomenology · Physics 2019-12-06 Nobuhito Maru , Yoshiki Yatagai

A series of Higgs field quantum numbers in the anti-grand unification model, based on the gauge group $SMG^3 \times U(1)_f$, is tested against the spectrum of quark and lepton masses and mixing angles. A more precise formulation of the…

High Energy Physics - Phenomenology · Physics 2009-11-07 C. D. Froggatt , H. B. Nielsen , D. J. Smith

We first discuss an approach to the fermion mass problem, according to which the whole of flavour mixing for quarks is determined by the mechanism responsible for generating the physical masses of the up and down quarks: the Lightest…

High Energy Physics - Phenomenology · Physics 2007-05-23 Colin D. Froggatt

We propose a new mass matrix ansatz: At the grand unified (GU) scale, the standard model (SM) Yukawa coupling matrix elements are integer powers of the square root of the GU gauge coupling constant \varepsilon \equiv…

High Energy Physics - Phenomenology · Physics 2014-11-20 Yong-Chao Zhang , De-Hai Zhang

This review is devoted to the Multiple Point Principle (MPP), according to which several vacuum states with the same energy density exist in Nature. The MPP is implemented to the Standard Model (SM), Family replicated gauge group model…

High Energy Physics - Phenomenology · Physics 2010-05-27 C. R. Das , L. V. Laperashvili

Different approaches to the fermion mass problem are reviewed. We illustrate these approaches by summarizing recent developments in models of quark and lepton mass matrices. Dynamical calculations of the top quark mass are discussed, based…

High Energy Physics - Phenomenology · Physics 2007-05-23 C. D. Froggatt

Grand Unified Theories predict relationships between the GUT-scale quark and lepton masses. Using new data in the context of the MSSM, we update the values and uncertainties of the masses and mixing angles for the three generations at the…

High Energy Physics - Phenomenology · Physics 2008-11-26 Graham Ross , Mario Serna

Addressing the fermion flavor structures using modular invariance is a challenging task in the framework of quark-lepton unification. Building on recent applications of modular symmetry in non-supersymmetric models, we propose the first…

High Energy Physics - Phenomenology · Physics 2025-08-05 Mohamed Amin Loualidi , Mohamed Miskaoui , Salah Nasri

When realizing the Minimal Supersymmetric Standard Model (MSSM) within a (simple) Grand Unified Theory (GUT), the predicted ranges for the strong coupling and the ratio of two Higgs doublet expectation values are strongly correlated with…

High Energy Physics - Phenomenology · Physics 2009-09-25 Nir Polonsky

In practically all extentions of the standard model, the neutrinos naturally acquire a mass. The neutrino mass matrix, however, contains many parameters which can neither be predicted by the prevailing models nor can be fitted to the data.…

High Energy Physics - Phenomenology · Physics 2007-05-23 G. K. Leontaris , J. D. Vergados
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