Three‐particle symmetry classifications according to the method of Dirac

It is shown that the method of Dirac is an effective way of teaching three‐particle symmetry classifications to students in the first‐year quantum mechanics class, who wish to understand the symmetry properties associated with elementary particles before or without learning group theory. According to the method spelled out for the N‐particle case by Dirac in Secs. 55 and 56 of his classic book Principles of Quantum Mechanics, explicit calculations are carried out for three particles. It is shown that this method leads to the three‐particle wave functions and their symmetric combinations as given by Feynman et al. In the following paper, the general principles derived here are applied to the quark model of hadrons.