Experimental Test of Local Hidden-Variable Theories
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We have measured the linear polarization correlation of the photons emitted in an atomic cascade of calcium. It has been shown by a generalization of Bell's inequality that the existence of local hidden variables imposes restrictions on this correlation in conflict with the predictions of quantum mechanics. Our data, in agreement with quantum mechanics, violate these restrictions to high statistical accuracy, thus providing strong evidence against local hidden-variable theories.
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Freedman's inequality requires only 3 coincidence measurements and is simpler mathematically and experimentally than the standard CHSH Bell test.
“Beyond the standard CHSH Bell test which requires 16 measurements, the so-called Freedman's inequality [79], [80] requires only 3 coincidence measurements with very simpler mathematical calculations and experiment, more understandable from the philosophical aspects and simpler physical interpretation, notably for undergraduate students in quantum optics Laboratories.”
From Nonlocal realism tests and quantum state tomography in Sagnac-based type-II polarization-entanglement SPDC-source (2021) · cites this paper as [80]
In the section labeled “theories with high statistical accuracy” (page unavailable), inequality (3) uses coincidence rates at 22.5° and 67.5° normalized to a reference rate with both polarizers removed, supporting the three-rate description. The paper does not compare its measurement count, mathematical difficulty, or experimental simplicity with a 16-measurement CHSH test. (LLM, conf=0.82)
Experimental — accuracy not yet measuredInitial experiments using photon pairs produced in an atomic cascade to test Bell's inequalities falsified Bell's inequalities and thus challenged the local realistic world-view.
“The initial experiments using photon pairs produced in an atomic cascade to test Bell's inequalities (Freedman and Clauser, 1972;Aspect et al., 1982aAspect et al., , 1982b, see also Clauser and Shimony 1978 for more experiments) falsified Bell's inequalities, and thus challenged the local realistic world-view.”
From Multiphoton entanglement and interferometry (2012) · cites this paper as Freedman and Clauser, 1972
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- Authors
- Freedman, S. J., & Clauser, J. F.
- Affiliations
- Lawrence Berkeley National Laboratory (US)
- Venue
- Physical Review Letters
- Publisher
- American Physical Society (APS)
- Published
- 1972-04-03
- Volume
- 28
- Issue
- 14
- Pages
- 938-941
- ISSN
- 0031-9007 (ISSN-L)
- OpenAlex
- W2052457796
- Cited by
- 1,999
- References
- 0
- Citations by year
- 2026: 69 · 2025: 108 · 2024: 131 · 2023: 199 · 2022: 92 · 2021: 61 · 2020: 66 · 2019: 97 · 2018: 47 · 2017: 58 · 2016: 87 · 2015: 73 · 2014: 60 · 2013: 67 · 2012: 59
- FWCI
- 8.52
- Type
- journal article
- Language
- en
- Open access
- bronze
- doi.org
- Locations
- Physical Review Letters (publishedVersion)
- eScholarship (California Digital Library) (submittedVersion)
- CERN Document Server (European Organization for Nuclear Research) (submittedVersion)
- Topics
- Physical Sciences › Physics and Astronomy › Atomic and Molecular Physics, and Optics › Quantum Mechanics and Applications
- Physical Sciences › Computer Science › Artificial Intelligence › Quantum Information and Cryptography
- Physical Sciences › Physics and Astronomy › Atomic and Molecular Physics, and Optics › Quantum optics and atomic interactions
- Keywords
- local hidden variable theories, Bell inequalities, polarization correlation, photon correlations, quantum mechanics
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