Equation Icon  ′ ′ ′ ′ [ˆac(Ω),ˆas(Ω )] = 2πiδ(Ω + Ω ), and [ˆac(Ω ),ˆac(Ω )] = [ˆas(Ω),ˆas(Ω )] = 0, (58 )