Related papers: A bottom-up approach to the strong CP problem
The various experimental bounds on flavor-changing interactions severely restrict the low-energy flavor structures of soft supersymmetry breaking parameters. In this work, we show that with a particular assumption of Yukawa couplings, the…
Based on experimental mass hierarchy, a set of flavor-democratic (FD) quark mass matrices at low energies is discussed. The model predicts CP violation parameters $J_{CP}=(0.3 \pm 0.2) 10^{-4}$ and ${\epsilon'/\epsilon} = (0.6 \pm 0.5)…
We investigate if the CP violation necessary for successful electroweak baryogenesis may be sourced by the neutrino Yukawa couplings. In particular, we consider an electroweak scale Seesaw realization with sizable Yukawas where the new…
We discuss what kinds of combinations of Yukawa interactions can generate the Majorana neutrino mass matrix. We concentrate on the flavor structure of the neutrino mass matrix because it does not depend on details of the models except for…
We study CP violation in a multi-Higgs doublet model based on a $S_3 \times Z_3$ horizontal symmetry where CKM phase is not the principal source of CP violation. We consider two mechanisms for CP violation in this model: a) CP violation due…
We present a supersymmetric solution to the strong CP problem based on spontaneous CP violation which simultaneously addresses the affects coming from supersymmetry breaking. The generated CP violating phase is communicated to the quark…
The minimal flavor structures for both quarks and leptons are proposed to address fermion mass hierarchy and flavor mixings by bi-unitary decomposition of the fermion mass matrix. The real matrix ${\bf M}_0^f$ is completely responsive to…
Supersymmetric models with a high supersymmetry breaking scale give, in general, large contributions to epsilon_K and/or to various electric dipole moments, even when contributions to CP conserving, flavor changing processes are…
A U(2)^3 flavour symmetry acting on the first two generations of quarks partially explains the hierarchies of the yukawa couplings, and provides a natural embedding for Supersymmetry with heavier first two generations, where collider…
A recent work combined the popular left-right parity (LR) and Peccei-Quinn (PQ) symmetries to explain the alignment in quark masses. Since axions may not exist, we break PQ softly and discover a new solution to the strong CP problem.…
The origin of the matter antimatter asymmetry of the universe remains unexplained in the Standard Model of particle physics. The origin of the flavour structure is another major puzzle of the theory. In this article, we report on recent…
One may argue that QCD solves the strong CP problem by itself, without having to introduce new symmetries and particles. To test this idea, a lattice simulation is performed. The problem is investigated in the CP$^3$ model first. It is…
I discuss vacuum alignment and CP violation in technicolor theories of electroweak and flavor symmetry breaking. I review the surprising appearance of rational phase solutions in the technifermion sector and propose a new solution of the…
In this letter we study the low-energy phenomenology and cosmological implications of supersymmetric grand unified theory with asymmetric flavor structure, which is suggested by the recent observation of fermion masses and mixing angles.…
We discuss a possible solution to the strong CP problem which is based on spontaneous CP violation and discrete symmetries. At the same time we predict in a simple way the almost right-angled quark unitarity triangle angle ($\alpha \simeq…
We consider the wrong-Higgs interactions such as type-III two Higgs doublet models. Generally, such interactions cause flavor problems. However, if new Yukawa interactions have the same flavor structure as that of the standard model(SM), we…
We discuss theoretical and phenomenological aspects of two-Higgs-doublet extensions of the Standard Model. In general, these extensions have scalar mediated flavour changing neutral currents which are strongly constrained by experiment.…
CP violation, which involves breaking the combined charge-conjugation (C) and parity (P) symmetries, is essential for understanding the observed matter-antimatter asymmetry in the universe. It is a key feature of the Standard Model,…
We investigate the viability of leptogenesis in models with three heavy right-handed neutrinos, where the charged-lepton and the neutrino Yukawa couplings are the only irreducible sources of lepton-flavour symmetry breaking (Minimal Lepton…
In a supersymmetric model with hierarchical squark masses we analyze a pattern of flavour symmetry breaking centered on the special role of the top Yukawa coupling and, by extension, of the full Yukawa couplings for the up-type quarks. For…