Quantum correlation interferometry in reflection: Application to the quantum-classical transition, decoherence, and indirect measurement

A many-body interferometer is described in which all of its components are treated as quantum objects. It consists of particles reflecting elastically from a "mirror". Quantum correlation is a consequence of conservation of energy and momentum while interference occurs when the order in which the non-local particles reflect is indeterminate. The resulting superposition exhibits correlated interference with diverse characteristics depending on the structure of the many-body wavegroup. Two non-local microscopic particles reflecting from a mesoscopic "mirror" illustrate unique features of this correlation interferometer. The microscopic momentum exchanged then results in small displacements of the superposed mesoscopic mirror substates, which mitigates experimental difficulties in determining the quantum-classical boundary. Quantum behavior of this mesoscopic mirror, evident in indirect measurements involving correlations between only the reflecting microscopic particles, disappears for a classical mirror which cannot exist in such superposition states.