Composite quarks and leptons

Calculability of quark and lepton masses and mixing angles is stressed as the primary motivation for constructing models in which quarks and leptons are composite particles. A general strategy for constructing such models is outlined in which quarks and leptons are kept light compared to their inverse sized by approximate chiral symmetries. The origin of multiple families is discussed, and an unrealistic model is exhibited which has several generations and a complicated pattern of masses and generation‐mixing angles. The new physics responsible for binding quarks and leptons tends to induce various rare processes at rates which are potentially too large.