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Is a time symmetric interpretation of quantum theory possible without retrocausality?
Matthew S Leifer1, Matthew F Pusey2
1Institute for Quantum Studies and Schmid College of Science and Technology, Chapman University, Orange, CA 92866, USA.
Proceedings. Mathematical, Physical, and Engineering Sciences
|July 11, 2017
Summary
This study challenges the necessity of retrocausality in time-symmetric quantum theory. By introducing λ-mediation, it demonstrates that a non-retrocausal time-symmetric ontology is impossible, offering new interpretations of Bell inequality violations.
Area of Science:
- Quantum mechanics
- Foundations of physics
- Philosophy of science
Background:
- Huw Price's argument posits that time-symmetric quantum ontologies necessitate retrocausality.
- A key assumption is the quantum state representing reality, which is challenged by no-go theorems.
- Retrocausality offers a potential way to circumvent these no-go theorems.
Purpose of the Study:
- To investigate whether retrocausality is essential for time-symmetric quantum ontologies.
- To replace the assumption of the quantum state's reality with a more general principle (λ-mediation).
- To provide a more precise framework for time symmetry in quantum theory.
Main Methods:
- Reformulating the assumptions of Price's argument.
- Introducing and utilizing the concept of λ-mediation.
- Analyzing the implications for time symmetry and causality.
Main Results:
- The assumption of the quantum state's reality can be replaced by λ-mediation.
- The reformulated argument implies a timelike analogue of Bell's local causality criterion.
- Timelike violations of Bell inequalities are reinterpreted as demonstrating the impossibility of non-retrocausal time-symmetric ontologies.
Conclusions:
- Retrocausality is not necessarily required for all time-symmetric quantum ontologies.
- The study establishes a new criterion for time symmetry and causality in quantum mechanics.
- It provides a novel interpretation for violations of Bell inequalities in a timelike context.
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