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arXiv · 2506.05545

Towards objectivity of classical reference frames in quantum mechanics

Rafał Ćwiek·Jarosław K. Korbicz
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Abstract

Recent advances in our understanding of foundations of quantum mechanics have shown that information can be made objective through quantum states. Such objectification processes, predicted e.g. in a variety of quantum open systems, must accompany any realistic quantum-to-classical transition mechanism in order to reproduce the objective character of the classical limit of our world. However, so far only examples of simple, unstructured information, such as a value of an observable, have been studied. In this work we show that a more complicated form of information, given by a Cartesian reference frame, can also be made (at least partially) objective in quantum mechanics. The non-trivial internal gauge structure of reference frames, given by the transformation group, leads to a more general form of objectivity, where all observers see the same but modulo their relative orientations, like it happens in modern understanding of geometry. This opens a way to extend quantum objectivity beyond simple scenarios and possibly link it to the foundations of modern geometry.

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Rafał Ćwiek, Jarosław K. Korbicz. 2025-06-05. Towards objectivity of classical reference frames in quantum mechanics. https://arxiv.org/abs/2506.05545

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