1. What is a unified theory?

            Einstein attempted to develop a unified field theory. “Field,” means force field which is an entity produced by a particle which extends from the particle and produces a force on another particle. An electron, for example, produces an electrostatic field. An adjacent second electron then is “repulsed” by this field. Alternatively, the second electron also produces a field which repulses the first electron. The main thrust of Einstein’s field theory effort was to obtain a single set of postulates from which he could derive both the electrostatic force and the gravitational force. His efforts were not successful.

            Actually a unified field theory should be defined as a theory from which all four of the known forces of physics can be derived. The four forces are gravitation, nuclear decay, electrostatic, and nuclear binding.

            A truly unified theory of physics is one from which all the forces as well as all the particles can be derived. The theory reported in The Grand Unified Theory of Physics begins with the postulated (billiard-ball) particles, derives the four forces, and derives the stable particles. It is believed that the short-lived particles also can be derived from the theory.