It's almost always the last topic in the first semester of introductory physics—angular momentum. Best for last, or something? I've used this concept to describe everything from fidget spinners to ...

This course introduces the quantum mechanical concept of angular momentum operator and its relationship with rotation operator. It then presents the angular momentum operators, their eigenvalues and ...

The Jahn-Teller effect, proposed by Jahn and Teller in 1937, describes how molecules or crystals with degenerate electronic orbitals can lower their total energy by distorting their structure. This ...