The Aharonov-Bohm effect for a constant scalar matter potential in neutrino flavour interferometry

Abstract

The Aharonov-Bohm effect is one of the most surprising wonders of the quantum world. The observed solenoid effect, as well as others, shows that a particle is affected by the potential in a region in which there is no force-field. This is so through the phase of the probability amplitude. Its interpretation is debated between a physical significance of the potential versus non-locality of quantum physics with the presence of the force-field generated by the potential difference outside this region. We demonstrate that the debate is resolved with the idea of replacing spatial interference by flavour interferometry as observed in neutrino oscillations. The neutrino propagation through the crust of the Earth in current facilities is affected by a constant scalar matter potential and the phase difference is in flavour internal properties. Here we show how to signal and experimentally disentangle the phase-shift due to the potential by means of observables characteristic of its symmetry properties. The energy dependence of the neutrino-antineutrino asymmetry in the golden transition $\nu_\mu \rightarrow \nu_e$ allows a clear separation of the matter component against the genuine asymmetry in the absence of the potential. These findings define, in a perfect symbiosis between quantum physics and particle physics, the path to observe in a single experiment the physical significance of the potential, the neutrino mass hierarchy and the genuine matter-antimatter asymmetry in the lepton sector.