Related papers: Quark and Lepton Masses and Mixing Angles from Sup…
We present a revised version of the so-called "yukawaon model", which was proposed for the purpose of a unified description of the lepton mixing matrix $U_{PMNS}$ and the quark mixing matrix $V_{CKM}$. It is assumed from a phenomenological…
The mass matrices of quarks have a simple structure if expressed in powers of the small parameter \sigma=(m_c/m_t)^{1/2}. If there is a close relation between quarks and leptons, one would expect similar structures for the lepton matrices…
We consider a flavor model based on A4 modular group to account for both lepton and quark parameters (masses and mixing). The inverse seesaw mechanism is considered to produce the light neutrino masses. Lepton masses and mixing are obtained…
We propose a supersymmetric composite model with three generations in which supersymmetry and electroweak symmetry are broken dynamically, and masses of quarks and leptons are generated without introducing any mass scales by hand. All the…
A very simple extension of the standard model to include an Abelian family symmetry is able to describe the hierarchy of quark and lepton masses and their mixing angles together with the unification of gauge couplings. We consider the…
The successful A4 family symmetry for leptons is applied to quarks, motivated by the quark-lepton assignments of SU(5). Realistic quark masses and mixing angles are obtained, in good agreement with data. In particular, we find a strong…
We study quark and lepton mass matrices with the common modulus $\tau$ in the $A_4$ modular symmetry. The viable quark mass matrices are composed of modular forms of weights $2$, $4$ and $6$. It is remarked that the modulus $\tau$ is close…
In the light of the gathering evidence for $\nu_{\mu}-\nu_{\tau}$ neutrino oscillations, coming in particular from the Super-Kamiokande data on atmospheric neutrinos, we re-analyze the unification of gauge and Yukawa couplings within the…
We analyze fermion mass-matrix structure in an asymptotically non-free model with 4 + 1bar generations. The texture at the GUT scale is uniquely determined by supposing that the masses of heavy up-type quarks (charm as well as top) are…
We construct a supersymmetric model based on $T'\otimes Z_3\otimes Z_9$ flavor symmetry. At the leading order, the charged lepton mass matrix is not diagonal, $T'$ is broken completely, and the hierarchy in the charged lepton masses is…
The pattern of lepton mixing can emerge from breaking a flavor symmetry in different ways in the neutrino and charged lepton Yukawa sectors. In this framework, we derive the conditions imposed on the mixing matrix by the structure of…
Using a low-energy effective field theory approach, we study some properties of models with large extra dimensions, in which quarks and leptons have localized wave functions in the extra dimensions. We consider models with two types of…
A mechanism is suggested by which the dynamics of confinement could be responsible for the fermion mass matrix. In this approach the large top quark Yukawa coupling is generated naturally during confinement, while those of the other quarks…
Assuming three light neutrinos and the see-saw mechanism we present a semiquantitative model of fermion masses based on (SUSY) SU(5) and abelian horizontal charges. A good description of the observed pattern of quark and lepton masses is…
We review recent work on realistic models that break supersymmetry dynamically and give rise to composite quarks and leptons, all in a single sector. These models have a completely natural suppression of flavor-changing neutral currents,…
We report a recent study on lepton masses within a beyond standard model with a SU(3) family symmetry model. In this scenario ordinary heavy fermions, top and bottom quarks and tau lepton become massive at tree level from Dirac See-saw…
We present a model which employs $CP\times Z_3$ symmetries where quark mixing and charged leptons masses are explained by following some texture. To achieve neutrino mass and mixing, we write a non-renormalizable Lagrangian using type-II…
We study the connection between quark and lepton mass matrices in a supersymmetric SO(10) GUT model in six dimensions, compactified on an orbifold. The physical quarks and leptons are mixtures of brane and bulk states. This leads to a…
We study the fermion mass and mixing hierarchy problems within the context of the SU(5) 4+1d domain-wall brane model of Davies, George and Volkas. In this model, the ordinary fermion mass relations of SU(5) grand unified theories are…
We construct a supersymmetric composite model in type IIA T^6/(Z_2 x Z_2) orientifold with intersecting D6-branes. Four generations of quarks and leptons are naturally emerged as composite fields at low energies. Two pairs of light…