量子理论的一个显著特征是其表面上的非决定论，即测量结果通常是概率性的。我们正式定义并探讨了这种不确定性是否不可避免，或者后量子理论是否能在平均遵循 Born 法则的同时提供预测优势。我们提出了一个结合三个方面的不可行主张：预测优势、无信号传输以及量子观察者之间可靠的主体间性。分析结果得出的结论是，真正的预测优势存在根本性限制。然而，我们发现了一个引人入胜的可能性：当不同观察者之间可靠的主体间性这一假设被违背时，主观预测优势原则上可以存在。这进而导致了同一理论的不同观察者之间存在认知边界。这些发现使我们接受量子不确定性作为自然可预测性限制的一个方面。
英文摘要：
One of quantum theory's salient features is its apparent indeterminism, i.e. measurement outcomes are typically probabilistic. We formally define and address whether this uncertainty is unavoidable or whether post-quantum theories can offer a predictive advantage while conforming to the Born rule on average. We present a no-go claim combining three aspects: predictive advantage, no-signalling, and reliable intersubjectivity between quantum observers. The results of the analysis lead to the conclusion that there exists a fundamental limitation on genuine predictive advantage. However, we uncover a fascinating possibility: When the assumption of reliable intersubjectivity between different observers is violated, subjective predictive advantage can, in principle, exist. This, in turn, entails an epistemic boundary between different observers of the same theory. The findings reconcile us to quantum uncertainty as an aspect of limits on Nature's predictability.
The View from Within: What Can Embedded Observers (Not) Learn?
Institute for Mathematics, University of Innsbruck（因斯布鲁克大学数学研究所）；Institute for Theoretical Physics, University of Innsbruck（因斯布鲁克大学理论物理研究所）；Departament d’Enginyeria, Universitat Pompeu Fabra（庞培法布拉大学工程学院）；ICREA, Institució Catalana d’Estudis i Recerca Avançats（加泰罗尼亚高级研究与教育学院）
The Measurement Problem Is a Feature, Not a Bug--Schematising the Observer and the Concept of an Open System on an Informational, or (Neo-)Bohrian, Approach
