Coherent States Measurement Entropy

Coherent states (CS) quantum entropy can be split into two components. The dynamical entropy is linked with the dynamical properties of a quantum system. The measurement entropy, which tends to zero in the semiclassical limit, describes the unpredictability induced by the process of a quantum approximate measurement. We study the CS–measurement entropy for spin coherent states defined on the sphere discussing different methods dealing with the time limit $n\to \mathrm{\infty }$. In particular we propose an effective technique of computing the entropy by iterated function systems. The dependence of CS–measurement entropy on the character of the partition of the phase space is analysed.