Angular Momentum in Quantum Physics: Theory and Application

6-j symbol algebra angular momentum operators angular momentum techniques applications atomic basis vectors body-fixed frame boson Chapter commutation relations components corresponding coupling defined definition denotes density matrix discussed E. P. Wigner eigenvalue electrons energy equation expression given by Eq H₁ Hamiltonian Hilbert space integral interaction invariant irrep isospin j₁ k₁ ket vectors L. C. Biedenharn l₁ labels linear m₁ Math molecule momenta multipole notation nuclear obtain orbital angular momentum orthogonal matrix orthonormal pair parameters particles permutations Phys physical polynomials problem properties quantum mechanics quantum numbers quaternion Racah coefficients radiation reduced matrix reduced matrix elements representation result rotation matrices scalar Section shell model solid harmonics spectra spherical harmonics spin symmetry tensor operators theorem total angular momentum transformation unitary vector operator wave functions Weyl Wigner coefficients Wigner operators Wigner-Eckart theorem