  The propagation of molecular chaos, a tool of classical kinetic theory, is
generalized to apply to quantum systems of distinguishable particles. We prove
that the Curie-Weiss model of ferromagnetism propagates molecular chaos and
derive the effective dynamics of a single-spin state in the mean-field limit.
Our treatment differs from the traditional approach to mean-field spin models
in that it concerns the dynamics of single-particle states instead of the
dynamics of infinite-particle states.
