Pure operations and measurements

@article{Hellwig1969PureOA,
  title={Pure operations and measurements},
  author={K. Hellwig and K. Kraus},
  journal={Communications in Mathematical Physics},
  year={1969},
  volume={11},
  pages={214-220}
}
States of a quantum system may be influenced by an external intervention. FollowingHaag andKastler, such a transformation of states is called an operation, and is called pure if it transforms pure states into pure states. Operations are discussed here under the assumption that they are caused by interactions with another system (apparatus), described by aS matrix. Pure operations are then shown to correspond, with one exception, to operatorsA with norm smaller than one. The Hermitean operatorsF… Expand
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  • A. Zorin
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  • 2019 11th International Congress on Ultra Modern Telecommunications and Control Systems and Workshops (ICUMT)
  • 2019
TLDR
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In diesem Uberblick beabsichtigen wir nicht, die Theorie des quantenmechanischen Mesprozesses mit allen Beweisen darzustellen. Dazu wurde der verfugbare Platz nicht ausreichen. Doch scheint es unsExpand