Joint Unitarity and a Single Definite Outcome in a Quantum Measurement
- URL: http://arxiv.org/abs/2605.22551v1
- Date: Thu, 21 May 2026 14:34:24 GMT
- Title: Joint Unitarity and a Single Definite Outcome in a Quantum Measurement
- Abstract summary: We investigate the possibility that a single measurement run with a definite outcome is a joint unitary evolution of all the participating systems.<n>We derived a lower bound of the dependence of the environment after measurement on the state of the system before measurement, conditioned on the same measurement outcome.
- Score: 0.0
- License: http://creativecommons.org/licenses/by/4.0/
- Abstract: We investigated the possibility that a single measurement run with a definite outcome is a joint unitary evolution of all the participating systems, and measurement runs with different definite outcomes correspond to different unitary maps. With reasonable assumptions, we derived a lower bound of the dependence of the environment after measurement on the state of the system before measurement, conditioned on the same measurement outcome. An experimental test of this dependence relation can either serve as evidence that the unitary dynamics and the definite outcome in the orthodox sense cannot be true together or suggest a deviation from the von Neumann measurement model plus a "conditioning" interpretational step.
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