Quantum detection and estimation theory

  title={Quantum detection and estimation theory},
  author={Carl W. Helstrom},
  journal={Journal of Statistical Physics},
  • C. Helstrom
  • Published 1969
  • Physics
  • Journal of Statistical Physics
A review. Quantum detection theory is a reformulation, in quantum-mechanical terms, of statistical decision theory as applied to the detection of signals in random noise. Density operators take the place of the probability density functions of conventional statistics. The optimum procedure for choosing between two hypotheses, and an approximate procedure valid at small signal-to-noise ratios and called threshold detection, are presented. Quantum estimation theory seeks best estimators of… 

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