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A reinterpretation of von Neumann's theory of measurement


Von Neumann's theory of measurement in quantum mechanics is reinterpreted so that the experimental arrangement specifies the location of the “cut” by calling for the separate observation of the object and the measuring apparatus after the initial measurement interaction. The measurement ascertains which element of the mixture describing the final state of the apparatus is actually present. The relevance and feasibility of observing the final coherent state of the object plus apparatus is criticized and the paradoxes of “Schrödinger's cat” and “Wigner's friend” are discussed.

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Work performed under the auspices of the U.S. Atomic Energy Commission.

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Moldauer, P.A. A reinterpretation of von Neumann's theory of measurement. Found Phys 2, 41–47 (1972).

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  • Quantum Mechanic
  • Coherent State
  • Measuring Apparatus
  • Experimental Arrangement
  • Initial Measurement