Quantum non-classicality in the simplest causal network

• URL: http://arxiv.org/abs/2404.12790v1
• Date: Fri, 19 Apr 2024 11:05:52 GMT
• Title: Quantum non-classicality in the simplest causal network
• Authors: Pedro Lauand, Davide Poderini, Rafael Rabelo, Rafael Chaves,
• Abstract summary: Bell's theorem prompts us with a fundamental inquiry: what is the simplest scenario leading to the incompatibility between quantum correlations and the classical theory of causality? Here we demonstrate that quantum non-classicality is possible in a network consisting of only three dichotomic variables, without the need of the locality assumption neither external measurement choices.
• Score: 0.41942958779358674
• License: http://creativecommons.org/licenses/by/4.0/
• Abstract: Bell's theorem prompts us with a fundamental inquiry: what is the simplest scenario leading to the incompatibility between quantum correlations and the classical theory of causality? Here we demonstrate that quantum non-classicality is possible in a network consisting of only three dichotomic variables, without the need of the locality assumption neither external measurement choices. We also show that the use of interventions, a central tool in the field of causal inference, significantly improves the noise robustness of this new kind of non-classical behaviour, making it feasible for experimental tests with current technology.

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