We consider two kinds of hierarchy problem in the Standard Model -- the gauge hierarchy and the fermion mass hierarchy. The solution models for these problems are presented and the phenomenology in those model is studied. The supersymmetry and the extra dimension is presented for the solution of the gauge hierarchy problem and the flavor symmetry is presented for the fermion mass hierarchy problem.
The intermediate scale string model with dilaton domination is interesting since it explains some problems in the usual string inspired supersymmetry models. We study the correlation between B→$X_sγ$ process, muon anomalous magnetic moment and dark matter detection in the intermediate scale string model. The model with extra dimension has been recently suggested. Randall-Sundrum model has a warped geometry in the direction of extra dimension and naturally generates the electroweak scale from Planck scale. There is a newly introduced scalar particle radion and we study the decay rate, the branching ratio and the production cross sections at linear and hadron colliders. The effective scalar potential is also considered and constraints on the radion mass and coupling are discussed.
Froggatt-Nielsen mechanism with Abelian flavor symmetry has been widely explored. We study non-Abelian SU(3) flavor symmetry. Under the conditions where the $K\ddot {a}hler$ potential has non-renormalizable terms and flavon F-term has non-vanishing VEV, we calculate the general trilinear A term and scalar mass terms.
