Related papers: Possible Gauge Theoretic Origin for Quark-Lepton C…
Scalar leptoquarks naturally arise within unified theories, offering a promising avenue for addressing one of the most significant challenges of the Standard Model--the existence of non-zero neutrino masses. In this work, we present a…
We describe our recent lattice study of SU(4) gauge theory with fermions in the fundamental and sextet representations. In this theory, a new type of baryon consists of quarks in both representations. The spectrum of these "chimera baryons"…
We show how the use of a see-saw mechanism based on a $3 \times 3$ neutrino mass matrix texture can considerably simplify Higgs sectors for quark-lepton symmetric models (and for Standard Model extensions generally). The main theory we…
We consider the phenomenological implications of a class of compactified string theories which naturally reproduces the flavour multiplet structure of the Standard Model. The implications for gauge unification depends on which of three…
With the progress of increasingly precise measurements on the neutrino mixing angles, phenomenological relations such as quark-lepton complementarity (QLC) among mixing angles of quarks and leptons and self-complementarity (SC) among lepton…
The lepton masses and mixings are studied on the basis of string inspired $SU(6)\times SU(2)_R$ model with global flavor symmetries. Provided that sizable mixings between lepton doublets $L$ and Higgsino-like fields $H_d$ with even R-parity…
Significant discrepancies between the different determinations of the Cabibbo angle have been observed. Here, we point out that this "Cabibbo-angle anomaly" can be explained by lepton flavour universality (LFU) violating New Physics (NP) in…
The unified compositeness of leptons, quarks and Higgs bosons is proposed as a possible scenario for New Physics beyond the Standard Model. The following topics of the scenario are briefly discussed: - Chiral gauge exceptional symmetry E_6…
Two models incorporating different forms of spontaneously broken quark-lepton symmetry are discussed. Both models are constructed so that quark-lepton symmetry can be broken at as low an energy scale as phenomenology allows, thus maximising…
We establish the existence of one-loop finite relations between the Cabibbo angle and the quark mass ratios, in the Standard Model with one Higgs doublet and two quark generations. Assuming a simple quark-lepton universality, we use the…
Recent data from astrophysical and terrestrial experiments indicates large mixing angles in the neutral lepton sector and restricts the allowed regions of neutrino masses. In particular, the large mixing angles in the lepton sector are…
We present a unification model based on the well-known but mysterious cubic-structure grouping of quarks and leptons that suggests an underlying symmetry connection deemed explainable by a unified theory. It results in an extension of the…
A model is presented that fits the quark and lepton masses and mixings wherein five dimensionless parameters and a phase account for fifteen dimensionless observables. Among these are the Wolfenstein parameters $\rho$ and $\eta$, the…
We propose a simple $SU(5)$ model that connects the neutrino mass generation mechanism to the observed disparity between the masses of charged leptons and down-type quarks. The model is built out of $5$-, $10$-, $15$-, $24$-, and…
Gauging a specific difference of lepton numbers such as $L_{\mu}-L_{\tau}$ is a popular model-building option, which gives rise to economical explanations for the muon anomalous magnetic moment. However, this choice of gauge group seems…
On the level of phenomenology unification-type idea of a basic connection between dimensionless mass and charge quantities requires particle mass copies and therefore is interesting as raison d'etre for particle flavor (degree of freedom).…
We study low energy implications of F-theory GUT models based on $SU(5)$ extended by a $U(1)'$ symmetry which couples non-universally to the three families of quarks and leptons. This gauge group arises naturally from the maximal…
A recent surge of interest in the {\em early} unification of quarks and leptons, has prompted us to revive a paper \cite{HBB} written twenty two years ago. We provided there a general discussion of quark-lepton unification characterized by…
The quark and charged lepton masses and the angles and phase of the CKM mixing matrix are nicely reproduced in a model which assumes SU(3)xSU(3) flavour symmetry broken by the v.e.v.'s of fields in its bi-fundamental representation. The…
We propose a predictive model based on the $SU(3)_{C}\otimes SU(3)_{L}\otimes U(1)_{X}$ gauge group supplemented by the $A_{4}\otimes Z_{3}\otimes Z_{4}\otimes Z_{6}\otimes Z_{16}$ discrete group, which successfully describes the SM fermion…