Quantum Observables and Ockham's Razor
For the paradigm of the quantum double-slit experiment (DSE), we apply Ockham's Razor to interpret quantum observations and to evaluate terminology associated with wave-particle duality. One finds that the Correspondence Principle (CP), combined with classical wave DSEs, e.g., Young [1804], is sufficient to separate and anticipate the observed quantum particle and wave phenomena. The empirical approach of Ockham infers that individual quanta are only whole particles during transit from source to detector; an individual quantum never acts as a wave. The wave nature of quanta emerges only in the distribution of large numbers of single-quantum observation events. That is, the "measurement problem" is no problem at all; "particle" and "wave" derive from separate and different aspects of a set of observations. Such artificial constructs as wave function collapse are irrelevant to the observation of individual quanta, each of which acts as a whole "particle" from emission to measurement. The histogram of detected events is a collective property identical to a classical wave interference pattern in the limit of large numbers, as the CP decrees. For a specific quantum, Ockham's Razor renders irrelevant any hypothesis regarding wave- or particle-like behavior of the quantum in the region between emission and detection. To analyze actual data sets consisting of a large number of identical observation events and to predict future DSEs, the CP of standard quantum (wave) mechanics is sufficient: in the limit, the distribution of observations approaches the continuous density defined by the standard quantum mechanical wave function. Scientific progress beyond this picture requires new, relevant experiments. From the DSE, Ockham's Razor infers that a theoretical quantum system consists of at least one quantum particle plus a wave function specifying the distribution of a large number of such particles.