Dynamical typicality of quantum expectation values.

@article{Bartsch2009DynamicalTO,
  title={Dynamical typicality of quantum expectation values.},
  author={Christian Bartsch and Jochen Gemmer},
  journal={Physical review letters},
  year={2009},
  volume={102 11},
  pages={
          110403
        }
}
We show that the vast majority of all pure states featuring a common expectation value of some generic observable at a given time will yield very similar expectation values of the same observable at any later time. This is meant to apply to Schrödinger type dynamics in high dimensional Hilbert spaces. As a consequence individual dynamics of expectation values are then typically well described by the ensemble average. Our approach is based on the Hilbert space average method. We support the… Expand
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