Quark and lepton masses from extra dimensions

The origin of the observed hierarchical pattern of quark and lepton masses remains as one of the big mysteries of particle physics. The standard model offers no explanation, fermion masses are simply parameterized by hierarchical Yukawa couplings. I discuss a new approach which explains the Yukawa coupling hierarchy with extra dimensions. If one postulates that the wave functions of the left- and right-handed components of the electron are localized at slightly different places in an extra dimension, then the electron Yukawa coupling is suppressed by the (generically exponentially small) overlap of these wave functions. I present an explicit model which utilizes this idea and show that splitting fermions in extra dimensions has spectacular signatures in high energy collisions.

hep group

Last modified: Thu Mar 22 16:43:18 EST 2001