If, only the commutation relations hold, using the following relation, | j , m ⟩ ⟩ → → U ( R ) | j , m ⟩ ⟩ = e x p ( − − i θ θ ℏ ℏ n ^ ^ ⋅ ⋅ J → → ) | j , m ⟩ ⟩ = ∑ ∑ m ′ D m ′ m ( j ) ( R ) | j , m ′ ⟩ ⟩