Transformations of Registration and Preparation Procedures. Transformations of Effects and Ensembles

Abstract

In II–IV we have been primarily motivated by physical considerations. In this chapter we shall be concerned with questions which play an important role in all mathematical theories—the definition and examination of the role of morphisms. The concepts presented in II–IV were motivated by physical considerations; here again the mathematical structure will reflect the physical situation. In this book we shall not investigate the underlying general mathematical problem itself because we are interested in the physical significance of the morphisms. We have already encountered this problem in previous chapters and have already anticipated some of the applications of morphisms. In VII we shall describe another important application; in XVII we shall become familiar with additional important physical examples of morphisms.