The meaning of protective measurements


Protective measurement, which we have introduced recently, allows one to observe properties of the state of a single quantum system and even the Schrödinger wave itself. These measurements require a protection, sometimes due to an additional procedure and sometimes due to the potential of the system itself The analysis of the protective measurements is presented and it is argued, contrary to recent claims, that they observe the quantum state and not the protective potential. Some other misunderstandings concerning our proposal are also clarified.

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This research was supported in part by grant PHY-9307708 of the National Science Foundation, and by ONR grant R & T 3124141.

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Aharonov, Y., Anandan, J. & Vaidman, L. The meaning of protective measurements. Found Phys 26, 117–126 (1996).

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  • Quantum State
  • Quantum System
  • Protective Measurement
  • Additional Procedure
  • Single Quantum