Relation between classical and quantum particle systems.

An exact correspondence is established between a N-body classical interacting system and a (N-1)-body quantum system with respect to the partition function. The resulting Hermitian quantum potential is a (N-1)-body one. Inversely the Kelbg potential is reproduced which describes quantum systems at a quasi-classical level. The correspondence found between classical and quantum systems allows also to approximate dense classical many-body systems by lower order quantum perturbation theory, replacing Planck's constant properly by temperature and density dependent expressions. As an example, the dynamical behavior of a one-component plasma is well reproduced concerning the formation of correlation energy after a disturbance, utilizing solely the analytical quantum-Born result for dense degenerated Fermi systems. As a practical guide, the quantum-Bruckner parameter r(s) has been replaced by the classical plasma parameter gamma as r(s) approximately 0.3gamma(3/2).