Single and Double Universal Seesaw Mechanisms with Universal Strength for Yukawa Couplings

Single and double universal seesaw mechanisms and the hypothesis of universal strength for Yukawa couplings are applied to formulate a unified theory of fermion mass spectrum in a model based on an extended Pati-Salam symmetry. Five kinds of Higgs fields are postulated to mediate scalar interactions among electroweak doublets of light fermions and electroweak singlets of heavy exotic fermions with relative Yukawa coupling constants of exponential form. At the first-order seesaw approximation, quasi-democratic mass matrices with equal diagonal elements are derived for all charged fermion sectors and a diagonal mass matrix is obtained for the neutrino sector under an additional ansatz. Assuming the vacuum neutrino oscillation, the problems of solar and atmospheric neutrino anomalies are investigated.Comment: 13 pages, LaTeX; a reference adde

Renormalization Group Effects on the Mass Relation Predicted by the Standard Model with Generalized Covariant Derivatives

Renormalization group analysis is made on the relation $m_{\rm H} \simeq \sqrt{2}m_t$ for masses of the top quark and the Higgs boson, which is predicted by the standard model based on generalized covariant derivatives with gauge and Higgs fields. This relation is a low energy manifestation of a tree level constraint which holds among the quartic Higgs self-coupling constant and the Yukawa coupling constants at a certain high energy scale $\mu_0$. With the renormalization group equation at one-loop level, the evolution of the constraint is calculated from $\mu_0$ down to the low energy region around the observed top quark mass. The result of analysis shows that the Higgs boson mass is in $m_t \lesssim m_{\rm H} \lesssim \sqrt{2}m_t$ for a wide range of the energy scale $\mu_0 \gtrsim m_t$ and it approaches to 177 GeV ($\approx m_t$) for large values of $\mu_0$.Comment: 13 pages, LaTeX, no figure

Approximate Sum Rules of CKM Matrix Elements from Quasi-Democratic Mass Matrices

To extract sum rules of CKM matrix elements, eigenvalue problems for quasi-democratic mass matrices are solved in the first order perturbation approximation with respect to small deviations from the democratic limit. Mass spectra of up and down quark sectors and the CKM matrix are shown to have clear and distinctive hierarchical structures. Numerical analysis shows that the absolute values of calculated CKM matrix elements fit the experimental data quite well. The order of the magnitude of the Jarlskog parameter is estimated by the relation $|J| \approx \sqrt{2}(m_c/m_t + m_s/m_b)|V_{us}|^2|V_{cb}|/4$.Comment: Latex, 15 pages, no figure

Nuclear Excitations Described by Randomly Selected Multiple Slater Determinants

We propose a new stochastic method to describe low-lying excited states of finite nuclei superposing multiple Slater determinants without assuming generator coordinates a priori. We examine accuracy of our method by using simple BKN interaction.Comment: Talk at International Symposium on Correlation Dynamics in Nuclei, Tokyo, Japan, 31 Jan.-- 4 Feb. 200