States and Dynamical Variables

In the previous chapter, we resorted to theHuygens–Fresnel superposition principle Huygens–Fresnel superposition principle to explain the discoveries of microscopic world and ended up with the quantum state as a superposition of detection states, such as the two polarization states in the Stern–Gerlach experiment. In this chapter, we shall show how the quantum–mechanical formalism of states and dynamical variables naturally arises from the analysis of measurements of observables made with experimental setups [SCW].