Griffith University, Australia
(joint work with Eric G. Cavalcanti)
In this work [1], we present a proof that Bell-Kochen-Specker inequality violations in phenomena satisfying no-disturbance (a generalisation of the no-signalling condition) cannot in general be explained by a classical causal model without fine-tuning. This result generalises the previous results of [2] and [3], by considering Bell scenarios with an arbitrary number of parties, or Kochen-Specker-contextuality scenarios with an arbitrary number of measurements per context. This unifies Bell nonlocality and Kochen-Specker contextuality as violations of a fundamental principle of classical causality.
[1] J. C. Pearl and E. G. Cavalcanti, (2019), arXiv:1909.05434 [quant-ph].
[2] C. J. Wood and R. W. Spekkens, New Journal of Physics 17, 033002 (2015).
[3] E. G. Cavalcanti, Physical Review X 8, 021018 (2018).