This paperback provides a thorough, didactic exposition of the role of symmetry, particularly rotational symmetry, in quantum mechanics. The bulk of the book covers the description of rotations (geometrically and group-theoretically) and their representations, and the quantum theory of angular momentum. Later chapters introduce more advanced topics

Introduction. Symmetry in quantum mechanics. Rotations in three-dimensional space. Angular momentum operators and eigenstates. Addition of angular momenta. Representations of the rotation group. The Jordan-Schwinger construction and representations. Irreducible tensors and tensor operators. Peculiarities of two-dimensional rotations: anyons, fractional spin and statistics. A brief glance at relativistic problems. Supersymmetry in quantum mechanics and particle physics. Appendices. Index