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  • Letter
  • Open Access

Quantum chaos without false positives

Dmitrii A. Trunin*

  • Moscow Institute of Physics and Technology, Institutskiy pereulok 9, Dolgoprudny 141701, Russia and Lebedev Physical Institute, Leninskiy prospect 53, Moscow 119991, Russia

  • *dmitriy.trunin@phystech.edu

Phys. Rev. D 108, L101703 – Published 29 November, 2023

DOI: https://doi.org/10.1103/PhysRevD.108.L101703

Abstract

Out-of-time-order correlators are widely used as an indicator of quantum chaos but give false-positive quantum Lyapunov exponents for integrable systems with isolated saddle points. We propose an alternative indicator that fixes this drawback and retains all advantages of out-of-time-order correlators. In particular, the new indicator correctly predicts the average Lyapunov exponent and the Ehrenfest time in the semiclassical limit, can be calculated analytically using the replica trick, and satisfies the bound on chaos.

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