Hirotaka Sugawara

Discrete symmetry and Cabibbo angle

S3 symmetry is assumed for the Higgs interaction with the quarks and the leptons and for the self-coupling of the Higgs bosons. We obtain tan θc = tan(φ − πr) = md/ms, where θc stands for the Cabibbo angle and φ is related to the CP violation.

Mass of the t-quark in SU(2) × U(1)☆

Abstract Using permutation symmetry for the Higgs couplings we find the quark and lepton masses to approximately satisfy m μ : m τ : m L …= m s : m b : m ′ b …= m c : m t : m ′ t … A more accurate calculation leads to m t ≈ 26 GeV. If there is a fourth lepton and a fourth quark doublet, we anticipate their masses to be m L ∼30 GeV, m ′ t ∼450 GeV and m ′ b ∼ 100 GeV.

Broken S3 symmetry in flavor physics

Abstract The S 3 symmetry is shown to be a very good approximate symmetry when it is broken in a specific way. This is true both in quark sector and in lepton sector. The way to break it is implied by the K–M mechanism applied not to the mixing matrix but to the mass matrices. In quark sector, we have an almost perfect fitting to the experimental data, and in lepton sector, we have a precision for the θ 13 .

Trimuon production by neutrinos and SU(8)L × U(1) gauge model

Abstract A gauge model of weak interactions is proposed to naturally incorporate copious production of charged heavy leptons leading to trimuon events in high energy neutrino reactions and a small violation of muon number conservation.

M-Theory Phenomenology and See-Saw Mechanisms

A version of M-theory phenomenology is proposed in which the symmetry is based on the group SO (10) × SO (10) × SO (10) × U (1) × U (1). Each SO (10) group acts on a single generation. The U (1) × U (1) is regarded as the hidden sector symmetry group. The supersymmetry is broken in the hidden sector by the Fayet-Iliopoulos D -term for each group. The D -term is needed also to circumvent the powerful non-renormalization theorem since the SO (10) × SO (10) × SO (10) is broken down to the usual SO (10) by the pair condensation of certain messenger sector multiplets. The exchange of U (1) gauge bosons gives an attractive force for the pair to be created and condensed. The off-diagonal mass matrix elements among the generations in these messenger sector multiplets are the source of the flavor dynamics including the CP violation. The pair condensation of another multiplet in the messenger sector leads to the doublet-triplet splitting. The SO (10) decuplet Higgs couples only to one of the generations. The other couplings should, therefore, be calculated as higher order corrections. We present our preliminary results on the calculation of the mass matrices and the mixing angles for leptons and quarks in this model.

Theory of quark confinement based on an analogy with a theory of magnetic monopoles

A nonlocal theory of quark confinement is proposed. The confinement is achieved by generalizing the theory of magnetic monopoles. Monopoles and quarks satisfy similar equations of motion, at least formally except that the string attached to the monopoles is unphysical whereas the string which originates from the quarks carries the energy. (AIP)