A modified Mach-Zehnder experiment to test the applicability of quantum theory to single-particle experiments

ABSTRACT We propose a modi“ed single-particle Mach-Zehnder interferometer experiment in which the path length of onearm may change (randomly or systematically) according to the value of an external two-valued variable x ,foreach passage of a particle through the interferometer. Quantum theory predicts an interference pattern that isindependent of the sequence of the values of x . On the other hand, corpuscular models that reproduce the resultsof quantum optics experiments carried out up to this date show a reduced visibility and a shift of the interferencepattern depending on the details of the sequence of the values of x . The key question to be answered in a reallaboratory experiment is: Which interference pattern is observed? Despite the general believe that quantumtheory might be used to describe all single particle experiments, this is an interesting question to be answeredsince in the proposed experiment the experimental conditions not only continuously change but they might alsohave causal eects on the passage of the photons through the interferometer. The proposed experiment can beused to determine to what extent quantum theory provides a description of observed events beyond the usualstatistical level.Keywords: Interference, quantum theory, Mach-Zehnder interferometer, single photons, event-by-event simu-lation