Diffusive Hydrodynamics of Out-of-Time-Ordered Correlators with Charge Conservation

  title={Diffusive Hydrodynamics of Out-of-Time-Ordered Correlators with Charge Conservation},
  author={Tibor Rakovszky and F. Pollmann and C. W. von Keyserlingk},
  journal={Physical Review X},
The scrambling of quantum information in closed many-body systems has received considerable recent attention. Two useful measures of scrambling have emerged: the spreading of initially-local operators, and the related concept of out-of-time-ordered correlation functions (OTOCs). Recently, random circuits have been used to give these quantities an effective hydrodynamical description. We extend these results by considering local random unitary circuits with a conserved U$(1)$ charge and argue… 

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