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Symmetry breaking and measurement theory


For studying the problem of measurement we accept the statistical interpretation of quantum mechanics, but we take into account, that in a sequence of measurements, offdiagonal terms arise which cannot obviously be interpreted as the probability of a sequence of macroscopic events. We demonstrate, however, their vanishing for ordinary measurement processes by observing that the measurement apparatus undergoes a symmetry breaking transition during the measurement.

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1. On leave from the Central Research Institute for Physics, Budapest, Hungary.

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Zimanyi, G.T., Vladar, K. Symmetry breaking and measurement theory. Found Phys Lett 1, 175–185 (1988).

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Key words

  • measurement theory
  • symmetry breaking
  • macroscopic limit