“…In the case of the twist proposed by Vafa and Witten [10] the SU(4) is splitted as SU(2) F × SU(2) I , so that the twisted global symmetry group turns out to be SU (2) (2) F is a residual internal symmetry group. The fields of the N = 4 multiplet are given by (A µ ,λ α u ,λ u α , Φ uv ), where (u, v = 1, .., 4) are indices of the fundamental representation of SU (4), and the six real scalar fields of the model are collected into the antisymmetric and selfconjugate tensor Φ uv . Under the twisted group, these fields decompose as…”