Quantum Bounds on the Generalized Lyapunov Exponents

@article{Pappalardi2022QuantumBO,
  title={Quantum Bounds on the Generalized Lyapunov Exponents},
  author={Silvia Pappalardi and Jorge Kurchan},
  journal={Entropy},
  year={2022},
  volume={25}
}
We discuss the generalized quantum Lyapunov exponents Lq, defined from the growth rate of the powers of the square commutator. They may be related to an appropriately defined thermodynamic limit of the spectrum of the commutator, which plays the role of a large deviation function, obtained from the exponents Lq via a Legendre transform. We show that such exponents obey a generalized bound to chaos due to the fluctuation–dissipation theorem, as already discussed in the literature. The bounds for… 

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