We present a simple model of gauge mediated supersymmetry breaking with composite messenger fields. Our model is based on the gauge group SP (8) × SU(2). By the strong SP (8) dynamics, supersymmetry is dynamically broken and the composite fields with charges under the standard model gauge group appear at low energy. The U(1)R symmetry breaking mass terms for the composite fields are generated b...

On the basis of the universal seesaw mass matrix model, which is a promising model of the unified description of the quark and lepton mass matrices, the behaviors of the gauge coupling constants and intermediate energy scales in the SO(10)L × SO(10)R model are investigated related to the neutrino mass generation scenarios. The non-SUSY model cannot give favorable values of the intermediate ener...

We deal with extensions of the Standard Model by adding horizontal interactions between particle generations. We calculate two loop corrections caused by the presence of coupling between hypothetical horizontal gauge bosons and matter field, both at low and high energy. It is proved numerically that the coupling of such extra bosons does not affect the positive features of unified and extended ...

We suggest that the magnetic monopoles predicted by grand unified theories would not be produced in significant numbers if electromagnetic gauge invariance is spontaneously broken when the temperature T is greater than Tc 2 1 TeV. A model possessing this behavior is displayed and the cosmological implications are discussed. Submitted to Physical Review Letters * Work supported by the Department...

We explore the effects of three-loop minimal supersymmetric standard model renormalisation group equation terms and some leading two-loop threshold corrections on gauge and Yukawa unification: each being one loop higher order than current public spectrum calculators. We also explore the effect of the higher order terms (often 2-3 GeV) on the lightest CP even Higgs mass prediction. We illustrate...

Starting from non-minimal supergravity theory with unified gauge symmetry, we obtain the low-energy effective theory by taking the flat limit and integrating out the superheavy fields in a model-independent manner. The scalar potential has extra non-universal contributions to soft supersymmetry breaking terms which can give an impact on phenomenological study. 1 Talk presented at YKIS’95, Kyoto...

The integrable systems associated with Seiberg-Witten geometry are considered both from the Hitchin-Donagi-Witten gauge model and in terms of intermediate Jacobians of Calabi-Yau threefolds. Dual pairs and enhancement of gauge symmetries are discussed on the basis of a map from the Donagi-Witten “moduli” into the moduli of complex structures of the Calabi-Yau threefold. Based on a lecture given...

We give an introduction to the dynamical symmetry breaking with large anomalous dimension. This is the basis of tightly bound composite Higgs models such as walking technicolor, strong ETC technicolor and top quark condensate, which are all characterized by the large anomalous dimension, γm ≃ 1 (walking technicolor), 1 < γm < 2 (strong ETC technicolor) and γm ≃ 2 (top quark condensate) due to n...

Several topics from the subject of supersymmetric field theories are reviewed. We first present the structure of the minimal supersymmetric standard model. Next we discuss the issue of the doublet-triplet splitting problem in supersymmetric grand unified theories. We show some necessary conditions which a viable model has to satisfy and present three models which successfully solve the doublet-...

Gauge-Yukawa unified theories, and in particular those which are finite beyond the unification scale, have been extended to include a soft supersymmetry breaking (SSB) sector. In the case of the Finite Unified Theories a new solution to the condition of twoloop finiteness of the SSB parameters is found, which requires a sum rule for the relevant scalar masses. The sum rule permits violations of...