This class builds on basic concepts introduced in the Applied Quantum Mechanics course (MSE227) and expands towards more advanced topics. It covers angular momentum, spin angular momentum, including Clebsch-Gordan coefficients and Kramers theorem. Approximation methods are also addressed, such as perturbation theory, variational method, and time-dependent perturbation within the interaction picture, as well as adiabatic theorem and Berry's phase and quantum theory of scattering. Finally, relativistic quantum mechanics and Dirac equation will be introduced.