Tracing quantum correlations back to collective interferences

Jonte R Hance*, Tomonori Matsushita, Holger F Hofmann

*Corresponding author for this work

Research output: Contribution to journalArticle (Academic Journal)peer-review


In this paper, we investigate the possibility of explaining nonclassical correlations between two quantum systems in terms of quantum interferences between collective states of the two systems. We achieve this by mapping the relations between different measurement contexts in the product Hilbert space of a pair of two-level systems onto an analogous sequence of interferences between paths in a single-particle interferometer. The relations between different measurement outcomes are then traced to the distribution of probability currents in the interferometer, where paradoxical relations between the outcomes are identified with currents connecting two states that are orthogonal and should therefore exclude each other. We show that the relation between probability currents and correlations can be represented by continuous conditional (quasi)probability currents through the interferometer, given by weak values; the violation of the noncontextual assumption is expressed by negative conditional currents in some of the paths. Since negative conditional currents correspond to the assignment of negative conditional probabilities to measurements results in different measurement contexts, the necessity of such negative probability currents represents a failure of noncontextual local realism. Our results help to explain the meaning of nonlocal correlations in quantum mechanics, and support Feynman's claim that interference is the origin of all quantum phenomena.
Original languageEnglish
Article number063021
Number of pages11
JournalNew Journal of Physics
Issue number6
Publication statusPublished - 19 Jun 2024

Bibliographical note

Publisher Copyright:
© 2024 The Author(s). Published by IOP Publishing Ltd on behalf of the Institute of Physics and Deutsche Physikalische Gesellschaft.

Structured keywords

  • Centre for Science and Philosophy
  • QETLabs
  • Bristol Quantum Information Institute
  • Photonics and Quantum


Dive into the research topics of 'Tracing quantum correlations back to collective interferences'. Together they form a unique fingerprint.

Cite this