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arXiv · 2511.09758

Local arrows of time in quantum many-body systems

Andrew G. Yates·Jordan Cotler·Nishad Maskara·Mikhail D. Lukin
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Abstract

We demonstrate that in quantum many-body systems, local arrows of time can differ from the global time $t$ induced by Hamiltonian evolution. That is, within a quantum many-body system, the flow of time can be relative to each observer or by proxy each local subsystem. We provide a definition of local arrows of time in quantum many-body systems, and explain their relation to spacetime quantum entropies. Then we give a variety of numerical and analytical examples which explore different ways in which local arrows of time can manifest in quantum many-body dynamics, including exotic arrows of time arising from quantum thermalization and quantum error correction.

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Andrew G. Yates, Jordan Cotler, Nishad Maskara, Mikhail D. Lukin. 2025-11-12. Local arrows of time in quantum many-body systems. https://arxiv.org/abs/2511.09758

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