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arXiv · 2512.24304

In defense of temporal Tsirelson bound

Antoni Wójcik·Jan Wójcik
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Abstract

In a recent paper, Chatterjee et al. [Phys. Rev. Lett 135, 220202 (2025)] analyze and experimentally implement a specific unitary evolution of a simple quantum system. The authors refer to this type of dynamics as a "superposition of unitary time evolutions." They claim that such an evolution enables a violation of the temporal Tsirelson bound in the Leggett-Garg scenario, a claim that is supported by their experimental results. In this work, we show that the proposed evolution can be understood within a more conventional framework, without invoking a superposition of evolutions. Furthermore, we demonstrate that the apparent violation of the bound arises because the measured quantities are not consistent with the assumptions of the Leggett-Garg scenario.

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Antoni Wójcik, Jan Wójcik. 2025-12-30. In defense of temporal Tsirelson bound. https://arxiv.org/abs/2512.24304

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