Perfect monopole action for infrared SU(2) QCD Original Research Article

Performing block-spin transformations on the dual lattice after abelian projection, we obtain an almost perfect lattice action in terms of monopole currents in the infrared region of pure SU(2) QCD. The action depends only on a physical scale b and is free from a cut-off a(β). It reproduces analytically the string tension which is near the physical one for a wide physical-scale region (b ⩾ 1.0(κ−12)).