ABSTRACT
This chapter considers elementary particles of spin, and constituents of the matter, and tabulates principal features of the elementary particles of spin. In 1928, Dirac formulated a satisfactory theory for particles of spin. The chapter provides a list of particles, called baryons, formed from three quarks. Dirac’s initial idea was that the differential equation satisfied by the wave function must lead to an equation of continuity associated with a density of probability defined as being positive. The chapter compares the classical relativistic hamiltonian of a particle in an electromagnetic field. The magnetic momentum is provoked by either an internal movement of the electron or by the spin of the electron. The electric momentum is an imaginary quantity, and consequently, it cannot be considered as having any meaning in physics. The chapter discusses the Schrodinger equation of an electron placed in a region of space where an electromagnetic field exists.
