At What Time Does a Quantum Experiment Have a Result?

  • Thomas PashbyEmail author
Part of the Tutorials, Schools, and Workshops in the Mathematical Sciences book series (TSWMS)


This paper provides a general method for defining a generalized quantum observable (or POVM) that supplies properly normalized conditional probabilities for the time of occurrence (i.e., of detection). This method treats the time of occurrence as a probabilistic variable whose value is to be determined by experiment and predicted by the Born rule. This avoids the problematic assumption that a question about the time at which an event occurs must be answered through instantaneous measurements of a projector by an observer, common to both Rovelli [22] and Oppenheim et al. [17]. I also address the interpretation of experiments purporting to demonstrate the quantum Zeno effect, used by Oppenheim et al. [17] to justify an inherent uncertainty for measurements of times.


Positive Operator-valued Measure (POVM) Quantum Zeno Effect Rovelli Born Rule Instantaneous Measurements 
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© Springer International Publishing AG 2017

Authors and Affiliations

  1. 1.Department of PhilosophyUniversity of ChicagoChicagoUSA

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