# Hidden observables in neutron quantum interferometry

**ABSTRACT** Neutron interferometry using monolithic perfect single crystals has become an important tool for fundamental, nuclear, and solid-state physics research. New features of quantum mechanics become measurable by means of neutron interferometry. Such features are quantum phases, which provide a more direct access to properties of wave functions and permit wave function reconstruction, and wave function engineering. Most recently, new experiments concerning off-diagonal and non-cyclic geometrical phases, confinement induced phases, and contextuality related experiments have been performed. These experiments show an intrinsic entanglement of different degrees of freedom of a single particle. Proper post-selection experiments yield to more quantum complete experiments and may help to make quantum mechanics less mystic. Unavoidable quantum losses may play an important role to explain the transition from the quantum to the classical world. All these investigations concern the heart of quantum mechanics and demonstrate the non-local feature of this theory.

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**ABSTRACT:**The special and unique techniques of neutron interferometry have been used to observe a number of topological effects. These include the quantum mechanical phase shift of a neutron due to the Earth's rotation (the quantum analog of the Michelson–Gale–Pearson experiment with light), the phase shift of a particle carrying a magnetic moment (a neutron) encircling a line charge (the Aharonov–Casher effect) and the scalar Aharonov–Bohm effect, observed with a pulsed magnetic field solenoid and time-of-flight neutron detection. On the occasion of the 50th anniversary of the Aharonov–Bohm paper, we provide an overview of the neutron interferometry technique and a description of these three historic experiments.Journal of Physics A Mathematical and Theoretical 08/2010; 43(35):354006. DOI:10.1088/1751-8113/43/35/354006 · 1.69 Impact Factor - [Show abstract] [Hide abstract]

**ABSTRACT:**Based on our model of quantum systems as emerging from the coupled dynamics between oscillating "bouncers" and the space-filling zero-point field, a sub-quantum account of nonlocal correlations is given. This is explicitly done for the example of the "double two-slit" variant of two-particle interferometry. However, it is also shown that the entanglement in two-particle interferometry is only a natural consequence of the fact that already a "single" two-slit experiment can be described on a sub-quantum level with the aid of "entangling currents" of a generally nonlocal nature.10/2012; DOI:10.1063/1.4773130 - [Show abstract] [Hide abstract]

**ABSTRACT:**We present a new tool for calculating the interference patterns and particle trajectories of a double-, three- and N-slit system on the basis of an emergent sub-quantum theory developed by our group throughout the last years. The quantum itself is considered as an emergent system representing an off-equilibrium steady state oscillation maintained by a constant throughput of energy provided by a classical zero-point energy field. We introduce the concept of a "relational causality" which allows for evaluating structural interdependences of different systems levels, i.e. in our case of the relations between partial and total probability density currents, respectively. Combined with the application of 21st century classical physics like, e.g., modern nonequilibrium thermodynamics, we thus arrive at a "super-classical" theory. Within this framework, the proposed current algebra directly leads to a new formulation of the guiding equation which is equivalent to the original one of the de Broglie-Bohm theory. By proving the absence of third order interferences in three-path systems it is shown that Born's rule is a natural consequence of our theory. Considering the series of one-, double-, or, generally, of N-slit systems, with the first appearance of an interference term in the double slit case, we can explain the violation of Sorkin's first order sum rule, just as the validity of all higher order sum rules. Moreover, the Talbot patterns and Talbot distance for an arbitrary N-slit device can be reproduced exactly by our model without any quantum physics tool.Annals of Physics 08/2013; 343. DOI:10.1016/j.aop.2014.02.002 · 3.07 Impact Factor