Related papers: Generating the fermion mass hierarchy at the TeV s…
We summarize the results showing that all existing data on mixing between up and down fermion states (i.e. CKM matrix and neutrino oscillations) and on the hierarchical quark and lepton mass ratios between generations are consistent with…
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…
The Standard Model of particle physics requires Yukawa matrices with eigenval- ues that differ by orders of magnitude. We propose a novel way to explain this fact without any small or large parameters. The mechanism is based on the…
Recently, we proposed a unified mass matrix model for quarks and leptons, in which, mass ratios and mixings of the quarks and neutrinos are described by using only the observed charged lepton mass values as family-number-dependent…
We propose a low scale renormalizable left-right symmetric theory that successfully explains the observed SM fermion mass hierarchy, the tiny values for the light active neutrino masses and is consistent with the lepton and baryon…
We show that the observed structure of quark and lepton masses and mixing angles can arise entirely geometrically from superstring constructions, at the renormalizable level. The model we consider is a $Z_3$ orbifold compactification of…
A general operator expansion is presented for quark and lepton mass matrices in unified theories based on a U(2) flavor symmetry, with breaking parameter of order $V_{cb} \approx m_s/m_b \approx \sqrt{m_c/m_t}$. While solving the…
We present an $E_6$ Grand Unified model with a realistic pattern of fermion masses. All standard model fermions are unified in three fundamental 27-plets (i.e. supersymmetry is not invoked), which involve in addition right handed neutrinos…
We have investigated a flavour model [1] which inspired by small squared-mass difference measured in solar neutrino oscillation experiments and observability in neutrinoless double beta decay experiments. In our model, the $1^{\rm st.}$ and…
The low-energy neutrino physics constraints on the TeV scale type I see-saw scenarios of neutrino mass generation are revisited. It is shown that lepton charge (L) violation, associated to the production and decays of heavy Majorana…
Assuming that mass scales arise in nature only via dimensional transmutation, we extend the dimension-less Standard Model by adding vector-like fermions charged under a new strong gauge interaction. Their non-perturbative dynamics generates…
We perform a detailed analysis of lepton flavour violation (LFV) within minimal see-saw type extensions of the Standard Model (SM), which give a viable mechanism of neutrino mass generation and provide new particle content at the…
We show how introducing discrete Abelian flavor symmetries can produce texture zeros in the fermion mass matrices, while preserving the correct relationships with the low-energy data on quark and lepton masses. We outline a procedure for…
In pursuit of a balance between theoretical naturalness and experimental testability, we propose two classes of multiple seesaw mechanisms at the TeV scale to understand the origin of tiny neutrino masses. They are novel extensions of the…
We present Unified Flavor (UF), a framework that synthesizes the $B$-lattice flavor hierarchy with a dynamical realization based on TeV-scale vectorlike fermion (VLF) chains. Hierarchical Yukawa couplings arise from discrete…
We discuss the general framework for the construction of new models containing a single, fermion number zero scalar leptoquark of mass $\simeq 200-220$ GeV which can both satisfy the D0/CDF search constraints as well as low energy data, and…
Electroweak Baryogenesis, given a first order phase transition, does not work in the standard model because the quark Yukawa matrices are too hierarchical. On the other hand, the neutrino mass matrix is apparently not hierarchical. In…
We propose a new framework for the observed flavor hierarchy and mixing based on left-right supersymmetry. The model contains the most minimal Higgs sector consisting only of gauge doublets which forbid the standard model Yukawa couplings.…
We propose new textures for the fermion Yukawa matrices which are generalizations of the so-called Stech ansatz. We discuss how these textures can be realized in supersymmetric grand unified models with horizontal symmetry SU(3)_H among the…
We consider the generation of fermion masses in an emergent model of electroweak symmetry breaking with composite $W,Z$ gauge bosons. A universal bulk fermion profile in a warped extra dimension is used for all fermion flavors. Electroweak…