Causality is a seminal concept in science: Any research discipline, from sociology and medicine to physics and chemistry, aims at understanding the causes that could explain the correlations observed among some measured variables. While several methods exist to characterize classical causal models, no general construction is known for the quantum case. In this work, we present quantum inflation, a systematic technique to falsify if a given quantum causal model is compatible with some observed correlations. We demonstrate the power of the technique by reproducing known results and solving open problems for some paradigmatic examples of causal networks. Our results may find applications in many fields: from the characterization of correlations in quantum networks to the study of quantum effects in thermodynamic and biological processes.

中文翻译：

---

量子膨胀：量子因果兼容性的一般方法

因果关系是科学中的一个开创性概念：从社会学和医学到物理学和化学的任何研究学科都旨在了解可以解释某些测量变量之间相关性的原因。虽然存在几种表征经典因果模型的方法，但对于量子情况尚无一般的构造。在这项工作中，我们介绍了量子膨胀，这是一种系统的技术，它可以用来验证给定的量子因果模型是否与某些观察到的相关性兼容。我们通过重现已知结果并解决因果网络的一些范例问题来解决开放问题，从而证明该技术的强大功能。我们的结果可能会在许多领域找到应用：从量子网络中相关性的表征到热力学和生物过程中量子效应的研究。