A Gauge Field Model On $SU(2)_L\times SU(2)_R\times U(1)_Y \times   \pi_4(G_{YM})$
  We reconstruct the Lagrangian of a left-right symmetric model with the gauge group $SU(2)_L\times SU(2)_R\times U(1)_Y \times \pi_4(SU(2)_L\times SU(2)_R\times U(1)_Y) $. The Higgs fields appear as gauge fields on discrete gauge group $\pi_4(SU(2)_L\times SU(2)_R\times U(1)_Y) $ and are assigned in a way complying with the principle that both the original gauge group $G_{YM}$ and the discrete group $\pi_4(G_{YM})$ should be taken as gauge groups in sense of non-commutative geometry. 
Bin Chen, Han-Ying Guo, Hong-Bo Teng and Ke Wu