arXiv:quant-ph/9511001 · International Journal of Modern Physics B
CLASSICAL BEHAVIOR IN QUANTUM MECHANICS: A TRANSITION PROBABILITY APPROACH
Nicolaas P. Landsman
Abstract
A formalism is developed for describing approximate classical behavior in finite (but possibly large) quantum systems. This is done in terms of a structure common to classical and quantum mechanics, viz. a Poisson space with a transition probability. Both the limit where ħ→0 in a fixed finite system and the limit where the size of the system goes to infinity are incorporated. In either case, classical behavior is seen only for certain observables and in a restricted class of states.