Addition of Angular Momentum

Since total angular momentum is conserved in nature, we will find that eigenstates of the
total angular momentum operator are usually energy eigenstates.
The exceptions will be when we apply external Fields which break the rotational symmetry.
We must therefore learn how to add different components of angular momentum together.
One of our first uses of this will be to add the orbital angular momentum in Hydrogen to the
spin angular momentum of the electron.

Our results can be applied to the addition of all types of angular momentum.

This material is covered in **Gasiorowicz Chapter 15,**
in **Cohen-Tannoudji et al. Chapter X**and very briefly in Griffiths Chapter 6.

- Adding the Spins of Two Electrons
- Total Angular Momentum and The Spin Orbit Interaction
- Adding Spin to Integer Orbital Angular Momentum
- Spectroscopic Notation
- General Addition of Angular Momentum: The Clebsch-Gordan Series
- Interchange Symmetry for States with Identical Particles
- Examples
- Counting states for Plus spin
- Counting states for Arbitrary Plus spin
- Adding to
- Two electrons in an atomic P state
- The parity of the pion from .

- Derivations and Computations
- Commutators of Total Spin Operators
- Using the Lowering Operator to Find Total Spin States
- Applying the Operator to and .
- Adding any plus spin .
- Counting the States for .

- Homework Problems
- Sample Test Problems

Jim Branson 2013-04-22