Is single-particle interference spooky?

Abstract

It is said about quantum interference that "In reality, it contains the only mystery". Indeed, together with non-locality it is often considered as the characteristic feature of quantum theory which can not be explained in any classical way. In this work we are concerned with a restricted setting of a single particle propagating in multi-path interferometric circuits, that is physical realisation of a qudit. It is shown that this framework, including collapse of the wave function, can be simulated with classical resources without violating the locality principle. We present a local ontological model whose predictions are indistinguishable from the quantum case. 'Non-locality' in the model appears merely as an epistemic effect arising on the level of description by agents whose knowledge is incomplete. This result suggests that the real quantum mystery should be sought in the multi-particle behaviour, since single-particle interferometric phenomena are explicable in a classical manner.

arXiv comment14 pages, 2 figures

References in corpus (10)

• Hidden Variables and the Two Theorems of John Bell
• In defense of the epistemic view of quantum states: a toy theory
• Is the quantum state real? An extended review of $\psi$-ontology theorems
• Anomalous Weak Values Are Proofs of Contextuality
• How the result of a single coin toss can turn out to be 100 heads
• Nonlocality of a single particle
• Nonnegative subtheories and quasiprobability representations of qubits
• Ontological models and the interpretation of contextuality
• Disentangling Nonlocality and Teleportation
• Quantum cube: A toy model of a qubit