Macroscopic Limit of Quantum Systems

@article{Polonyi2021MacroscopicLO,
  title={Macroscopic Limit of Quantum Systems},
  author={Janos Polonyi},
  journal={Universe},
  year={2021}
}
Classical physics is approached from quantum mechanics in the macroscopic limit. The technical device to achieve this goal is the quantum version of the central limit theorem, derived for an observable at a given time and for the time-dependent expectation value of the coordinate. The emergence of the classical trajectory can be followed for the average of an observable over a large set of independent microscopical systems, and the deterministic classical laws can be recovered in all practical… Expand

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