Bell's Inequalities and Density Matrices: Revealing "Hidden" Nonlocality.

  title={Bell's Inequalities and Density Matrices: Revealing "Hidden" Nonlocality.},
  journal={Physical review letters},
  volume={74 14},
  • Popescu
  • Published 5 February 1995
  • Physics
  • Physical review letters
Standard Bell inequalities apply to correlations arising when two or more macroscopically separated systems are each subjected to a single ideal measurement. While these inequalities demonstrate that quantum mechanics and local hidden variable theories yield incompatible predictions for pure states, they fail for mixed states: For mixed states, correlations arising from a single ideal measurement on each system may obey standard Bell inequalities, yet when each system is subjected to a sequence… 
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Preface Part I. Reflections on the Pursuit of Physics: 1. E. pluribus boojum: the physicist as neologist 2. Commencement address 3. One of the great physicists ... and great characters 4. My life
For an extensive reference list , see L . Khalfin and B . Tsirelson , Found
  • Phys . Rev . Lett .
  • 1992