U(1)A_A Models of Fermion Masses Without a μ\mu Problem

We discuss the connection between models of fermion masses and mixing involving a string-motivated flavor/generation U(1)$_A$ gauge symmetry and the $\mu$ term. We point out that in a certain class of such models the flavor physics can provide an appealing solution to the $\mu$ problem, naturally yielding a $\mu \sim O(m_{_W})$. A simple relationship between the $U(1)_A$ charge $q_{H}$ of the $\mu$-term and the average generational $U(1)_A$ charges of the down quark and leptonic sectors is derived. Finally, we construct an explicit model illustrating our results.Comment: 12 pages, Latex Fil

Supergravity Coupled to Chiral Matter at One Loop

We extend earlier calculations of the one-loop contributions to the effective bose Lagrangian in supergravity coupled to chiral matter. We evaluate all logarithmically divergent contributions for arbitrary background scalar fields and space-time metric. We show that, with a judicious choice of gauge fixing and of the definition of the action expansion, much of the result can be absorbed into a redefinition of the metric and a renormalization of the K\"ahler potential. Most of the remaining terms depend on the curvature of the K\"ahler metric. Further simplification occurs in models obtained from superstrings in which the K\"ahler Riemann tensor is covariantly constant.Comment: 33 pages, LBL-34457, UCB-PTH-93-2

Classical Isomorphisms for Quantum Groups

The expressions for the $\hat{R}$--matrices for the quantum groups SO$_{q^2}$(5) and SO$_q$(6) in terms of the $\hat{R}$--matrices for Sp$_q$(2) and SL$_q$(4) are found, and the local isomorphisms of the corresponding quantum groups are established.Comment: 11 page

Models of Fermion Mass Matrices Based on a Flavor- and Generation-Dependent U(1) Gauge Symmetry

We study models of fermion mass matrices based on a flavor- and generation-dependent string-motivated U(1)$_A$ gauge symmetry and report two new classes of solutions to the requisite consistency conditions. In particular, we propose that the fundamental reason underlying the striking feature $m_b, \ m_\tau << m_t$ is that all of the elements of the down-quark and charged lepton effective Yukawa matrices actually arise from higher-dimension operators, suppressed by inverse powers of the Plank mass. An explicit model embodying this idea is constructed.Comment: 11 pages, late

On the High TT Phase Transition in the Gauged SU(2)SU(2) Higgs Model

We study the effective field theory of a weakly coupled 3+1d gauged $\phi^4$ type model at high temperature. Our model has $4N$ real scalars ($N$ complex Higgs doublets) and a gauge group $SU(2)$ which is spontaneously broken by a nonzero scalar field $vev$ at zero temperature. We find, for sufficiently large $N$, that the transition from the high temperature symmetry restoring phase to the low temperature phase can be either first order or second order depending on the ratio of the gauge coupling to the scalar self coupling.Comment: 16 pages. 1 Figure, not include