The $\mu\tau$-reflection symmetry is a simple symmetry capable of predicting all the unknown CP phases of the lepton sector and the atmospheric angle but too simple to predict the absolute neutrino mass scale or the mass ordering.
By combining this symmetry with a discrete abelian symmetry in a nontrivial way
we can additionally enforce a texture-zero for the heavy neutrino mass matrix which...
Neutrino is recognized to have a tiny but non-zero mass by some physical phenomena, such as the neutrino oscillation. However, the Standard Model cannot fully describe how the neutrinos get their masses. The beyond Standard Model which adds the necessary modification for this problem has been required. As a possibility to solve the neutrino mass problem, the seesaw mechanism has been...
Some novel notions of lepton and baryon numbers are discussed, with applications to dark matter as well as the strong CP problem.
The first part of my talk is devoted to the discussion of the first model where the SM fermion mass hierarchy is generated by a sequential loop suppression mechanism: tree-level top quark mass; 1-loop bottom, charm, tau and muon masses; 2-loop masses for the light up, down and strange quarks as well as for the electron; and 4-loop masses for the light active neutrinos. The model features...
We show how an accidental U(1) Peccei-Quinn (PQ) symmetry can arise in a realistic Pati-Salam unified theory of flavour. A QCD axion arises from a linear combination of A4 triplet favons, which are responsible for fermion flavour structures and thus specific flavour-violating couplings of the axion are predicted. We also discuss the prospect of probing such a flavourful axion in future experiments.
The Standard Model (SM) of particle physics is a big success. However, it lacks
an explanation of cosmic inflation, of the matter-anti-matter asymmetry of the Universe, of dark matter, of neutrino oscillations, and of the feebleness of strong CP violation. The latter may be explained by an extension of the Standard Model by a complex scalar field charged under a spontaneously broken global...
