Quantum mechanical interaction-free measurements

  title={Quantum mechanical interaction-free measurements},
  author={Avshalom C Elitzur and Lev Vaidman},
  journal={Foundations of Physics},
A novel manifestation of nonlocality of quantum mechanics is presented. It is shown that it is possible to ascertain the existence of an object in a given region of space without interacting with it. The method might have practical applications for delicate quantum experiments. 

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