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arXiv · 2512.11198

Theory of Out-of-Time-Ordered Transport

Ruchira Mishra·Jiaozi Wang·Silvia Pappalardi·Luca V. Delacrétaz
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Abstract

We construct an effective field theory (EFT) that captures the universal behavior of out-of-time-order correlators (OTOCs) at late times in generic quantum many-body systems with conservation laws. The EFT hinges on a generalization of the strong-to-weak spontaneous symmetry breaking pattern adapted to out-of-time-order observables, and reduces to conventional fluctuating hydrodynamics when time-ordered observables are probed. We use the EFT to explain different power-law behavior observed in OTOCs at late times, and show that many OTOCs are entirely fixed by conventional transport data. Nevertheless, we show that a specific combination of OTOCs is sensitive to novel transport parameters, not visible in regular time-ordered correlators. We test our predictions in Hamiltonian and Floquet spin chains in one dimension.

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Ruchira Mishra, Jiaozi Wang, Silvia Pappalardi, Luca V. Delacrétaz. 2025-12-12. Theory of Out-of-Time-Ordered Transport. https://arxiv.org/abs/2512.11198

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