Speaker
Christoph Luhn
Description
The observed hierarchies of fermion masses and mixing angles can be explained in the framework of Froggatt and Nielsen by imposing a family dependent U(1) symmetry. Based on a supersymmetric setting, we consider the possibility of a flavor U(1) R-symmetry which breaks down to a remnant Z4 R-symmetry. While containing R-parity as a subgroup, this discrete R-symmetry provides a solution to the mu-problem by forbidding the bilinear Hu Hd term.
