Deconstruction of Gauge Symmetry Breaking by Discrete Symmetry and G Unification

We deconstruct the non-supersymmetric SU(5) breaking by discrete symmetry on the space-time M4×S1 and M×S/(Z2×Z ′ 2) in the Higgs mechanism deconstruction scenario. And we explain the subtle point on how to exactly match the continuum results with the latticized results on the quotient space S/Z2 and S /(Z2 ×Z ′ 2). We also propose an effective deconstruction scenario and discuss the gauge symmetry breaking by the discrete symmetry on theory space in this approach. As an application, we suggest the G unification where G is broken down to SU(3) × SU(2) × U(1)n−3 by the bifundamental link fields and the doublet-triplet splitting can be achieved. PACS: 11.25.Mj; 04.65.+e; 11.30.Pb; 12.60.Jv