Yukawa hierarchy transfer based on superconformal dynamics and geometrical realization in string models

We propose a scenario that leads to hierarchical Yukawa couplings anddegenerate sfermion masses at the same time, in the context ofextra-dimensional models, which can be naturally embedded in a wide class ofstring models. The hierarchy of Yukawa couplings and degeneracy of sfermionmasses can be realized thanks to superconformal gauge dynamics. The sfermionmass degeneracy is guaranteed by taking the superconformal fixed point to befamily independent. In our scenario, the origin of Yukawa hierarchy isattributed to geometry of compactified dimensions and the consequent volumedependence of gauge couplings in the superconformal sectors. The difference inthese gauge couplings is dynamically transferred to the hierarchy of the Yukawacouplings. Thus, our scenario combines a new dynamical approach and theconventional geometrical approach to the supersymmetric flavor problem.Comment: 12 pages, latex, no figur