Possible reason why leptons are lighter than quarks

Abstract

The minimal model of spontaneously broken leptonic colour and discrete quark-lepton symmetry predicts that charged leptons have the same masses as their partner charge $+2/3$ quarks up to small radiative corrections. By invoking a different pattern of symmetry breaking, a similar model can be constructed with the structural feature that charged leptons have to be lighter than their partner quarks because of mixing between leptonic colours, provided mixing between generations is not too strong. As well as furnishing a new model-building tool, this is phenomenologically interesting because some of the new physics responsible for the quark-lepton mass hierarchy could exist on scales as low as several hundred GeV.

(some minor errors corrected, and role of multiple generations discussed more extensively. Will appear in Phys Rev D.), 8 pages, plain Latex, UM-P-94/19

References in corpus (2)

• Discrete quark-lepton symmetry need not pose a cosmological domain wall problem
• Study of the simplest realistic Higgs sector in quark-lepton symmetric models

Cited by in corpus (5)

• Prospects for mass unification at low energy scales
• Unification via intermediate symmetry breaking scales with the quartification gauge group
• Neutrino masses in quartification schemes
• From $m_d=m_e$ to Realistic Mass Relations in Quark-Lepton Symmetric Models
• Phenomenology of the Two Higgs Doublet Sector of a Quark-Lepton Symmetric Model