ABSTRACT
The concept and much of the mathematical treatment of orbital angular momentum was treated in Chapter 3. An unexpected result from that treatment is that using the result of Equation (3.41) along with the result of Equation (3.48), we find that
mT −mB = 2` = n , (4.1) so ` is either an integer or a half integer! The integers correspond to orbital angular momentum, while the half-integer values correspond to intrinsic angular momentum, or spin angular momentum. There is no classical model for spin angular momentum, but the most fundamental particles (electrons, quarks, protons, and neutrons) all exhibit this type of intrinsic angular momentum.
