Research output: Contribution to journal › Article

**Is a time symmetric interpretation of quantum theory possible without retrocausality?** / Leifer, Matthew S.; Pusey, Matthew F.

Research output: Contribution to journal › Article

Leifer, MS & Pusey, MF 2017, 'Is a time symmetric interpretation of quantum theory possible without retrocausality?', *Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences*, vol. 473, 20160607. https://doi.org/10.1098/rspa.2016.0607

Leifer, M. S., & Pusey, M. F. (2017). Is a time symmetric interpretation of quantum theory possible without retrocausality? *Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences*, *473*, [20160607]. https://doi.org/10.1098/rspa.2016.0607

Leifer MS, Pusey MF. Is a time symmetric interpretation of quantum theory possible without retrocausality? Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences. 2017 Jun;473. 20160607. https://doi.org/10.1098/rspa.2016.0607

@article{2540cbe9288847ba9c8ac2226700d0bd,

title = "Is a time symmetric interpretation of quantum theory possible without retrocausality?",

abstract = "Huw Price has proposed an argument that suggests a time symmetric ontology for quantum theory must necessarily be retrocausal, i.e. it must involve influences that travel backwards in time. One of Price's assumptions is that the quantum state is a state of reality. However, one of the reasons for exploring retrocausality is that it offers the potential for evading the consequences of no-go theorems, including recent proofs of the reality of the quantum state. Here, we show that this assumption can be replaced by a different assumption, called λ-mediation, that plausibly holds independently of the status of the quantum state. We also reformulate the other assumptions behind the argument to place them in a more general framework and pin down the notion of time symmetry involved more precisely. We show that our assumptions imply a timelike analogue of Bell's local causality criterion and, in doing so, give a new interpretation of timelike violations of Bell inequalities. Namely, they show the impossibility of a (non-retrocausal) time symmetric ontology.",

author = "Leifer, {Matthew S.} and Pusey, {Matthew F.}",

year = "2017",

month = jun,

doi = "10.1098/rspa.2016.0607",

language = "English",

volume = "473",

journal = "Proceedings of the Royal Society of London. Series A, Mathematical and Physical Sciences",

issn = "1364-5021",

publisher = "Royal Society of London",

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T1 - Is a time symmetric interpretation of quantum theory possible without retrocausality?

AU - Leifer, Matthew S.

AU - Pusey, Matthew F.

PY - 2017/6

Y1 - 2017/6

N2 - Huw Price has proposed an argument that suggests a time symmetric ontology for quantum theory must necessarily be retrocausal, i.e. it must involve influences that travel backwards in time. One of Price's assumptions is that the quantum state is a state of reality. However, one of the reasons for exploring retrocausality is that it offers the potential for evading the consequences of no-go theorems, including recent proofs of the reality of the quantum state. Here, we show that this assumption can be replaced by a different assumption, called λ-mediation, that plausibly holds independently of the status of the quantum state. We also reformulate the other assumptions behind the argument to place them in a more general framework and pin down the notion of time symmetry involved more precisely. We show that our assumptions imply a timelike analogue of Bell's local causality criterion and, in doing so, give a new interpretation of timelike violations of Bell inequalities. Namely, they show the impossibility of a (non-retrocausal) time symmetric ontology.

AB - Huw Price has proposed an argument that suggests a time symmetric ontology for quantum theory must necessarily be retrocausal, i.e. it must involve influences that travel backwards in time. One of Price's assumptions is that the quantum state is a state of reality. However, one of the reasons for exploring retrocausality is that it offers the potential for evading the consequences of no-go theorems, including recent proofs of the reality of the quantum state. Here, we show that this assumption can be replaced by a different assumption, called λ-mediation, that plausibly holds independently of the status of the quantum state. We also reformulate the other assumptions behind the argument to place them in a more general framework and pin down the notion of time symmetry involved more precisely. We show that our assumptions imply a timelike analogue of Bell's local causality criterion and, in doing so, give a new interpretation of timelike violations of Bell inequalities. Namely, they show the impossibility of a (non-retrocausal) time symmetric ontology.

U2 - 10.1098/rspa.2016.0607

DO - 10.1098/rspa.2016.0607

M3 - Article

VL - 473

JO - Proceedings of the Royal Society of London. Series A, Mathematical and Physical Sciences

JF - Proceedings of the Royal Society of London. Series A, Mathematical and Physical Sciences

SN - 1364-5021

M1 - 20160607

ER -