Commutators (Draft) Basic vector operators: r i; p i. Vectors defined using r and p: L i = S j,k e ijk r j p k; a ± = [1/(2m) 1/2] [ p x ±imwx] Product rule: [A, BC] = [A, B]C + B[A, C] Fundamental commutators: [r i, r j] = 0 [p i, p j] = 0 [r i, p j] = i hbar d ij. Derivable commutators [ r i, S j p j 2] = 2 i hbar p i [ p i, S j r j 2 ...