In this second volume on the Foundations of Quantum Mechanics we shall
show how it is possible, using the methodology presented in Volume I, to
deduce some of the most important applications of quantum mechanics.
These deductions are concerned with the structures of the microsystems
rather than the technical details of the construction of preparation and
registration devices. Accordingly. the only new axioms (relative to
Volume I) which are introduced are concerned with the relationship
between ensemble operators W, effect operators F, and certain
construction principles of the preparation and registration devices. The
applications described here are concerned with the measurement of atomic
and molecular structure and of collision experiments. An additional and
essential step towards a theoretical description of the preparation and
registration procedures is carried out in Chapter XVII. Here we
demonstrate how microscopic collision processes (that is, processes
which can be described by quantum mechanics) can be used to obtain novel
preparation and registration procedures if we take for granted the
knowledge of only a few macroscopic preparation and registration
procedures. By clever use of collision processes we are often able to
obtain very precise results for the operators Wand F which describe the
total procedures from a very imprecise knowledge of the macroscopic
parts of the preparation and regis- tration processes. In this regard
experimental physicists have done brilliant work. In this sense Chapter
XVII represents a general theoretical foundation for the procedures used
by experimental physicists.
