Abstract

The term “frame of reference” is defined for both classical physics and quantum mechanics. The definition is the usual one, simply made explicit. It is used in the study of coherent superposition, and in particular the dependence on the observer (frame of reference) of the coherence of superposition of state vectors. This dependence is then used as the basis of an analysis of a criticism of previous work on the nonexistence of superselection rules. We again reach the conclusion that they do not exist