Constrained standard model from a compact extra dimension

A SU(3) × SU(2) × U(1) supersymmetric theory is constructed with a TeV sized extra dimension compactified on the orbifold S 1 /(Z2 × Z ′ 2). The compactification breaks supersymmetry leaving a set of zero modes which correspond precisely to the states of the 1 Higgs doublet standard model. Supersymmetric Yukawa interactions are localized at orbifold fixed points. The top quark hypermultiplet radiatively triggers electroweak symmetry breaking, yielding a Higgs potential which is finite and exponentially insensitive to physics above the compactification scale. This potential depends on only a single free parameter, the compactification scale, yielding a Higgs mass prediction of 127 ± 8 GeV. The masses of the all superpartners, and the Kaluza-Klein excitations are also predicted. The lightest supersymmetric particle is a top squark of mass 197 ±20 GeV. The top Kaluza-Klein tower The standard model provides an economical description of particles and their interactions in terms of 18 free parameters. There are 9 parameters associated with the masses of the quarks and charged leptons, and 4 to describe the flavor mixing of the quarks. There are 3 independent