A quantum experiment with joint exogeneity violation

Yuhao Wang; Xingjian Zhang

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arXiv · 2507.22747

A quantum experiment with joint exogeneity violation

Yuhao Wang·Xingjian Zhang

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Abstract

In randomized experiments, the assumption of potential outcomes is usually accompanied by the \emph{joint exogeneity} assumption. Although joint exogeneity has faced criticism as a counterfactual assumption since its proposal, no evidence has yet demonstrated its violation in randomized experiments. In this paper, we reveal such a violation in a quantum experiment, thereby falsifying this assumption, at least in regimes where classical physics cannot provide a complete description. We further discuss its implications for potential outcome modelling, from both practial and philosophical perspectives.

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Yuhao Wang, Xingjian Zhang. 2025-07-30. A quantum experiment with joint exogeneity violation. https://arxiv.org/abs/2507.22747

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