Quantum Instruments and Conditioned Observables

• URL: http://arxiv.org/abs/2005.08117v1
• Date: Sat, 16 May 2020 22:27:37 GMT
• Title: Quantum Instruments and Conditioned Observables
• Authors: Stan Gudder
• Abstract summary: Sequential products of effects and conditioned observables have been introduced. It is shown how these ideas can be unified within the framework of measurement models. Joint probabilities of observables are considered.
• Score: 0.0
• License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
• Abstract: Observables and instruments have played significant roles in recent studies on the foundations of quantum mechanics. Sequential products of effects and conditioned observables have also been introduced. After an introduction in Section~1, we review these concepts in Section~2. Moreover, it is shown how these ideas can be unified within the framework of measurement models. In Section~3, we illustrate these concepts and their relationships for the simple example of a qubit Hilbert space. Conditioned observables and their distributions are studied in Section~4. Section~5 considers joint probabilities of observables. We introduce a definition for joint probabilities and discuss why we consider this to be superior to the standard definition.

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