Quantum Mechanics Is Compatible with Counterfactual Definiteness
Counterfactual definiteness (CFD) means that if some property is measured in some context, then the outcome of the measurement would have been the same had this property been measured in a different context. A context includes all other measurements made together with the one in question, and the sp...
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| Format: | Article |
| Language: | English |
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MDPI AG
2023-09-01
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| Series: | Entropy |
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| Online Access: | https://www.mdpi.com/1099-4300/25/9/1356 |
| _version_ | 1797580185168510976 |
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| author | Janne V. Kujala Ehtibar N. Dzhafarov |
| author_facet | Janne V. Kujala Ehtibar N. Dzhafarov |
| author_sort | Janne V. Kujala |
| collection | DOAJ |
| description | Counterfactual definiteness (CFD) means that if some property is measured in some context, then the outcome of the measurement would have been the same had this property been measured in a different context. A context includes all other measurements made together with the one in question, and the spatiotemporal relations among them. The proviso for CFD is non-disturbance: any physical influence of the contexts on the property being measured is excluded by the laws of nature, so that no one measuring this property has a way of ascertaining its context. It is usually claimed that in quantum mechanics CFD does not hold, because if one assigns the same value to a property in all contexts it is measured in, one runs into a logical contradiction, or at least contravenes quantum theory and experimental evidence. We show that this claim is not substantiated if one takes into account that only one of the possible contexts can be a factual context, all other contexts being counterfactual. With this in mind, any system of random variables can be viewed as satisfying CFD. The concept of CFD is closely related to but distinct from that of noncontextuality, and it is the latter property that may or may not hold for a system, in particular being contravened by some quantum systems. |
| first_indexed | 2024-03-10T22:47:45Z |
| format | Article |
| id | doaj.art-e31308b6aa7e4839b07d44a450565980 |
| institution | Directory Open Access Journal |
| issn | 1099-4300 |
| language | English |
| last_indexed | 2024-03-10T22:47:45Z |
| publishDate | 2023-09-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Entropy |
| spelling | doaj.art-e31308b6aa7e4839b07d44a4505659802023-11-19T10:36:28ZengMDPI AGEntropy1099-43002023-09-01259135610.3390/e25091356Quantum Mechanics Is Compatible with Counterfactual DefinitenessJanne V. Kujala0Ehtibar N. Dzhafarov1Department of Mathematics and Statistics, University of Turku, FI-20014 Turun yliopisto, FinlandDepartment of Psychological Sciences, Purdue University, West Lafayette, IN 47907, USACounterfactual definiteness (CFD) means that if some property is measured in some context, then the outcome of the measurement would have been the same had this property been measured in a different context. A context includes all other measurements made together with the one in question, and the spatiotemporal relations among them. The proviso for CFD is non-disturbance: any physical influence of the contexts on the property being measured is excluded by the laws of nature, so that no one measuring this property has a way of ascertaining its context. It is usually claimed that in quantum mechanics CFD does not hold, because if one assigns the same value to a property in all contexts it is measured in, one runs into a logical contradiction, or at least contravenes quantum theory and experimental evidence. We show that this claim is not substantiated if one takes into account that only one of the possible contexts can be a factual context, all other contexts being counterfactual. With this in mind, any system of random variables can be viewed as satisfying CFD. The concept of CFD is closely related to but distinct from that of noncontextuality, and it is the latter property that may or may not hold for a system, in particular being contravened by some quantum systems.https://www.mdpi.com/1099-4300/25/9/1356contextualitycounterfactual definitenessstrong consistent connectedness |
| spellingShingle | Janne V. Kujala Ehtibar N. Dzhafarov Quantum Mechanics Is Compatible with Counterfactual Definiteness Entropy contextuality counterfactual definiteness strong consistent connectedness |
| title | Quantum Mechanics Is Compatible with Counterfactual Definiteness |
| title_full | Quantum Mechanics Is Compatible with Counterfactual Definiteness |
| title_fullStr | Quantum Mechanics Is Compatible with Counterfactual Definiteness |
| title_full_unstemmed | Quantum Mechanics Is Compatible with Counterfactual Definiteness |
| title_short | Quantum Mechanics Is Compatible with Counterfactual Definiteness |
| title_sort | quantum mechanics is compatible with counterfactual definiteness |
| topic | contextuality counterfactual definiteness strong consistent connectedness |
| url | https://www.mdpi.com/1099-4300/25/9/1356 |
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