where n ^ ^ is a fixed unit vector. Since ∇ ∇ × × S = λ λ T , it can be found that ∇ ∇ × × ( S + T ) = λ λ ( S + T ) . But this is same as the original equation, therefore H = S + T , where S is the poloidal field and T is the toroidal field. Thus, substituting T in S , we get the most general solution as