English

Out-of-time-order fluctuation-dissipation theorem

Statistical Mechanics 2018-02-07 v4 High Energy Physics - Theory Quantum Physics

Abstract

We prove a generalized fluctuation-dissipation theorem for a certain class of out-of-time-ordered correlators (OTOCs) with a modified statistical average, which we call bipartite OTOCs, for general quantum systems in thermal equilibrium. The difference between the bipartite and physical OTOCs defined by the usual statistical average is quantified by a measure of quantum fluctuations known as the Wigner-Yanase skew information. Within this difference, the theorem describes a universal relation between chaotic behavior in quantum systems and a nonlinear-response function that involves a time-reversed process. We show that the theorem can be generalized to higher-order nn-partite OTOCs as well as in the form of generalized covariance.

Keywords

Cite

@article{arxiv.1612.08781,
  title  = {Out-of-time-order fluctuation-dissipation theorem},
  author = {Naoto Tsuji and Tomohiro Shitara and Masahito Ueda},
  journal= {arXiv preprint arXiv:1612.08781},
  year   = {2018}
}
R2 v1 2026-06-22T17:35:36.478Z