Related papers: The mass ratios parametrization
The structure of the mass matrix, a challenging problem in the Standard Model, is closely related to flavor phenomenology and the understanding of the Yukawa interaction. We derive a factorized mass structure based on observed fermion mass…
$\mu$-$\tau$ symmetry imposed on the neutrino mass matrix in the flavour basis is known to be quite predictive. We integrate this very specific neutrino symmetry into a more general framework based on the supersymmetric SO(10) grand unified…
We consider a new approach to fermion masses and mixings in which no special "horizontal" dynamics is invoked to account for the hierarchical pattern of charged fermion masses and for the peculiar features of neutrino masses. The hierarchy…
We analyze fermion masses and mixing in a general warped extra dimensional model, where all the Standard Model (SM) fields, including the Higgs, are allowed to propagate in the bulk. In this context, a slightly broken flavor symmetry…
An extension of the Standard Model (SM) based on the non-Abelian discrete group $\Delta(27)$ is considered. The $\Delta(27)$ flavour symmetry is spontaneously broken only by gauge singlet scalar fields, therefore our model is free from any…
Family symmetries are possibly the most conservative extension of the Standard Model that attempt explanations of the pattern of fermion masses and mixings. The observed large mixing angles in the lepton sector may be the first signal for…
We study the general properties of hierarchical fermion mass matrices in which the small eigenvalues are stable with respect to perturbations of the matrix entries and we consider specific applications to the charged lepton contribution to…
For understanding the hierarchies of fermion masses and mixing, we extend the Standard Model gauge group with \( U(1)_X \) and \( Z_2 \) symmetry. The field content of the Standard Model is augmented by three heavy right-handed neutrinos,…
We study neutrino mass generation in models with four chiral families of leptons and quarks and four right handed neutrinos. Generically, in these models there are three different contributions to the light neutrino masses: the usual…
We present a new mechanism to explain naturally and through a common flavour symmetry the mildly hierarchical neutrino masses with large mixings and the hierarchical Yukawa matrices with small mixing angles. Although this mechanism is not…
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…
With a modest revision of the mass sector of the Standard Model, the systematics of the fermion masses and mixings can be fully described and interpreted as providing information on matrix elements of physics beyond the Standard Model. A…
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…
One puzzle of neutrino masses and mixings is that they do not exhibit the kind of strong "hierarchy" that is found for the quarks and charged leptons. Neutrino mass ratios and mixing angles are not small. A possible reason for this is…
The mass problem in particle physics for other fields is discussed. While the problem of the nuclear masses has been resolved within the QCD framework, 3 parameters of the ``Standard Model'' are related to the fermion sector. The origin of…
The mass problem in particle physics and its impact for other fields is discussed. While the problem of the nuclear masses has been resolved within the QCD framework, many parameters of the ``Standard Model'' are related to the fermion…
We perform a systematic study of the generic Gatto-Sartori-Tonin relation, $\tan^2\theta_{ij}= m_i/m_j$. This study of fermion mixing phenomena leads us to the necessary conditions that are needed in order to obtain it without any…
In the democratic universal seesaw model, the mass matrices are given by \bar{f}_L m_L F_R + \bar{F}_L m_R f_R + \bar{F}_L M_F F_R (f: quarks and leptons; F: hypothetical heavy fermions), m_L and m_R are universal for up- and down-fermions,…
Since the discovery of neutrino oscillations many ideas have been put forward to explain the special features of the leptonic mixing and the differences with respect to the quark sector. In this talk I review some of these proposals,…
The so-called Golden Mass Relation provides a testable correlation between charged-lepton and down-type quark masses, that arises in certain flavor models that do not rely on Grand Unification. Such models typically involve broken family…