Quark-Lepton Nonuniversality

Abstract

There is new experimental evidence which may be interpreted as a small departure from quark-lepton universality. We propose to understand this as the result of a hierarchy of mass scales in analogy to $m_u,m_d<<{\Lambda }_{QCD}$ for strong isospin. We show $(G_F{)}_{lq}^{NC}<(G_F{)}_{lq}^{CC}<(G_F{)}_{ll}^{CC}<(G_F{)}_{ll}^{NC}$ in principle, but all are still approximately equal. New physics is predicted at the TeV scale.

arXiv comment3 pages, talk by E. Ma at XXIII ENFPC, Aguas de Lindoia, Brazil (Oct 2002)