The DOI matches its Crossref record; 35 of the 35 references it cites were found in a registry or an index.
An experimental test of non-local realism
Open accessAbstract
Most working scientists hold fast to the concept of 'realism'--a viewpoint according to which an external reality exists independent of observation. But quantum physics has shattered some of our cornerstone beliefs. According to Bell's theorem, any theory that is based on the joint assumption of realism and locality (meaning that local events cannot be affected by actions in space-like separated regions) is at variance with certain quantum predictions. Experiments with entangled pairs of particles have amply confirmed these quantum predictions, thus rendering local realistic theories untenable. Maintaining realism as a fundamental concept would therefore necessitate the introduction of 'spooky' actions that defy locality. Here we show by both theory and experiment that a broad and rather reasonable class of such non-local realistic theories is incompatible with experimentally observable quantum correlations. In the experiment, we measure previously untested correlations between two entangled photons, and show that these correlations violate an inequality proposed by Leggett for non-local realistic theories. Our result suggests that giving up the concept of locality is not sufficient to be consistent with quantum experiments, unless certain intuitive features of realism are abandoned.
Overview
The claims and statistics of this paper haven’t been checked yet.
Run the check — free, no account needed. It reads the open-access text and checks the sources it cites.
Integrity signals
Registry
Cites
Statistics
Verification
Claims the paper makes
The claims and statistics of this paper haven’t been checked yet.
Run the check — free, no account needed. It reads the open-access text and checks the sources it cites.
Claims other papers make about this one
Each is checked against this paper’s own text: does it say what the citing paper says it does?
In the citing paper
“The observed S N LHV = 3.8521 ± 0.0227 violates inequality (68) by 3.2 standard deviations.”
From Multiphoton entanglement and interferometry (2012) · cites this paper as Gröblacher et al. (2007)
In the citing paper
“This way, Gröblacher et al. experiment excluded a broad class of nonlocal hidden-variable theories.”
From Multiphoton entanglement and interferometry (2012) · cites this paper as Gröblacher et al. (2007)
In the citing paper
“The Leggett-type inequality valid for nonlocal realistic theories of the discussed type was experimentally tested by Gröblacher et al. (2007).In the experiment a SPDC source of high-fidelity two-photon entangled states was used, with visibilities ∼ 99.0 ± 1.2% in the H/V basis, ∼ 99.2 ± 1.6% in the ±45 • basis and ∼ 98.9 ± 1.7% in the R/L basis.”
From Multiphoton entanglement and interferometry (2012) · cites this paper as Gröblacher et al. (2007)
In the citing paper
“At the same time measurements gave S Bell = 2.178 ± 0.0199, which violates the CHSH inequality by ∼9 standard deviations.”
From Multiphoton entanglement and interferometry (2012) · cites this paper as Gröblacher et al. (2007)
In the citing paper
“This, plus the above assumptions, implies a Leggett-type inequality (for details of the derivation see Groblacher et al., 2007) of the following form:”
From Multiphoton entanglement and interferometry (2012) · cites this paper as Groblacher et al., 2007
Self-check
Percentages, sums and reported differences re-computed from the paper’s own numbers.
The self-check needs the paper’s full text.
Citations
Cites
Can Quantum-Mechanical Description of Physical Reality Be Considered Complete?
Einstein, A., Podolsky, B., & Rosen, N. (1935) · Physical Review · doi:10.1103/physrev.47.777 · Cited by 16,654
On the Einstein Podolsky Rosen paradox
Bell, J. S. (1964) · Physics Physique Fizika · doi:10.1103/physicsphysiquefizika.1.195 · Cited by 12,252
Proposed Experiment to Test Local Hidden-Variable Theories
Clauser, J. F., Horne, M. A., Shimony, A., & Holt, R. A. (1969) · Physical Review Letters · doi:10.1103/physrevlett.23.880 · Cited by 7,573
A Suggested Interpretation of the Quantum Theory in Terms of "Hidden" Variables. I
Bohm, D. (1952) · Physical Review · doi:10.1103/physrev.85.166 · Cited by 5,510
Principles of Optics: Electromagnetic Theory of Propagation, Interference and Diffraction of Light
Born, M., Wolf, E., & Hecht, E. (2000) · Physics Today · doi:10.1063/1.1325200 · Cited by 4,185
Experimental Test of Bell's Inequalities Using Time- Varying Analyzers
Aspect, A., Dalibard, J., & Roger, G. (1982) · Physical Review Letters · doi:10.1103/physrevlett.49.1804 · Cited by 3,942
Die gegenw�rtige Situation in der Quantenmechanik
Schr�dinger, E. (1935) · Die Naturwissenschaften · doi:10.1007/bf01491891 · Cited by 3,392
Bell’s theorem without inequalities
Greenberger, D. M., Horne, M. A., Shimony, A., & Zeilinger, A. (1990) · American Journal of Physics · doi:10.1119/1.16243 · Cited by 2,404
Self-citationExperimental Tests of Realistic Local Theories via Bell's Theorem
Aspect, A., Grangier, P., & Roger, G. (1981) · Physical Review Letters · doi:10.1103/physrevlett.47.460 · Cited by 2,294
Experimental Test of Local Hidden-Variable Theories
Freedman, S. J., & Clauser, J. F. (1972) · Physical Review Letters · doi:10.1103/physrevlett.28.938 · Cited by 1,999
Cited by
Sorted by citations
Items 301–400 of 419
Hardy’s argument and successive spin- s measurements
Ahanj, A. (2010) · Physical Review A · doi:10.1103/physreva.82.012101 · Cited by 1
Socolovsky, M. (2008) · Advances in Applied Clifford Algebras · doi:10.1007/s00006-008-0136-1 · Cited by 1
The Physical World as a Virtual Reality: A Prima Facie Case
Whitworth, B. (2007) · Massey Research Online (Massey University) · Cited by 1
Leggett-type model with relaxed measurement independence
Zela, F. D. (2013) · Physical Review A · doi:10.1103/physreva.87.012124 · Cited by 1
On The Origin of Magnetism And Gravitation And On The Nature of Electricity And Matter
Hochecker, H.-J. (2016) · doi:10.12691/ijp-4-4-3 · Cited by 1
Information and Conditional Probability to Go beyond Hidden Variables
Nagata, K., Resconi, G., Nakamura, T., & Geurdes, H. J. F. (2016) · Journal of Applied Mathematics and Physics · doi:10.4236/jamp.2016.412214 · Cited by 1
Schmelzer, I. (2016) · Foundations of Physics · doi:10.1007/s10701-016-0046-3 · Cited by 1
Measurement Theory Based on the Truth Values Violates Local Realism
Nagata, K. (2016) · International Journal of Theoretical Physics · doi:10.1007/s10773-016-3176-7 · Cited by 1
What Does Quantum Theory Tell Us? A Matter-Wave Approach
Hasegawa, Y. (2016) · The frontiers collection · doi:10.1007/978-3-319-38987-5_24 · Cited by 1
Belinsky, A. V. (2018) · Optics and Spectroscopy · doi:10.1134/s0030400x18050041 · Cited by 1
Popovič, J. (2023) · Human Affairs · doi:10.1515/humaff-2022-1013 · Cited by 1
Nonlocality, Superposition, and Time in the 4+1 Formalism
Strubbe, F. (2023) · Entropy · doi:10.3390/e25111493 · Cited by 1
Experimentally Ruling Out Joint Reality Based on Locality with Device-Independent Steering
Zhang, S., Zhang, X., Zheng, Z., & Zhang, W. (2023) · Chinese Physics Letters · doi:10.1088/0256-307x/41/1/010301 · Cited by 1
Persistency of quantum non-multi-local correlations in noisy acyclic networks
Yang, S., Hou, J., & He, K. (2024) · Physica Scripta · doi:10.1088/1402-4896/ad35f7 · Cited by 1
On removing the classical-quantum boundary
Mnaymneh, K. (2024) · AIP Advances · doi:10.1063/5.0206221 · Cited by 1
Precision Limit for Observation: The Bridge for Quantum Classical Transitions
Li, S., Liang, C., & Jin, M. (2025) · Journal of Quantum Information Science · doi:10.4236/jqis.2025.151004 · Cited by 1
Briegel, H. J., & Müller, T. (2025) · Synthese Library/Synthese library · doi:10.1007/978-3-031-98119-7_3 · Cited by 1
Kastrup, B. (2019) · The Journal of near-death studies · doi:10.17514/jnds-2019-37-3-p185-200 · Cited by 1
The Mind-Brain Problem and the Problem of Free Will
Fountoulakis, K. Ν. (2021) · Springer eBooks · doi:10.1007/978-3-030-86541-2_16 · Cited by 1
Any nonlocal model assuming "local parts" conflicts with relativityPreprint
Suárez, A. (2013) · arXiv (Cornell University) · doi:10.48550/arxiv.1304.4801 · Cited by 1
Hidden variable models for entanglements can or cannot have a local component?Preprint
Wechsler, S. (2008) · arXiv (Cornell University) · doi:10.48550/arxiv.0804.3686 · Cited by 1
The origin of quantum nonlocalityPreprint
Hong, F.-Y. (2010) · arXiv (Cornell University) · doi:10.48550/arxiv.1002.0959 · Cited by 1
Macroscopic polarization entanglement and loophole-free Bell inequality testPreprint
Stobińska, M., Horodecki, P., Buraczewski, A., Chhajlany, R. W., Horodecki, R., & Leuchs, G. (2009) · arXiv (Cornell University) · doi:10.48550/arxiv.0909.1545 · Cited by 1
Non-classical light for quantum information
Goldschmidt, E. A. (2013) · University Libraries (University of Maryland) · Cited by 1
Васильевич, П. Л. (2009) · Physics of Particles and Nuclei Letters · doi:10.1134/s1547477109010014 · Cited by 1
Recent tests of realistic models
Brida, G., Degiovanni, I. P., Genovese, M., Gramegna, M., Piacentini, F., Schettini, V., & Traina, P. (2009) · Journal of Physics Conference Series · doi:10.1088/1742-6596/174/1/012014 · Cited by 1
Ultrabright omnidirectional collective emission of correlated photon pairs from atomic vapors
Huang, Y., & Moore, M. G. (2010) · Physical Review A · doi:10.1103/physreva.81.033807 · Cited by 1
Quantum Mechanics and Nonlocality: In Search of Instructive DescriptionPreprint
Vlasov, A. Y. (2009) · arXiv (Cornell University) · doi:10.48550/arxiv.0901.4645 · Cited by 1
Homogeneous and genuine Bell inequalities
Zela, F. D. (2009) · Physical Review A · doi:10.1103/physreva.79.022102 · Cited by 1
Leggett's inequality, the before-before experiment, and free will on the part of NaturePreprint
Suárez, A. (2008) · arXiv (Cornell University) · doi:10.48550/arxiv.0801.3050 · Cited by 1
Experimental multi-photon entanglement and quantum enhanced metrology
Krischek, R. (2011) · doi:10.5282/edoc.13270 · Cited by 1
Suárez, A. (2010) · arXiv (Cornell University) · doi:10.48550/arxiv.1007.0536 · Cited by 1
Does it matter whether God plays dice
Lee, S. (2013) · Cited by 1
On Quantum Gravity If Non-Locality Is FundamentalPreprint
Kauffman, S. A. (2021) · OSF Preprints (OSF Preprints) · doi:10.31219/osf.io/jqtyh · Cited by 1
Burgdörfer, J., & Rotter, S. (2009) · Wiley eBooks · doi:10.1002/3527600434.eap367.pub2 · Cited by 1
Brown, W. (2023) · Qeios · doi:10.32388/v5edgf.2 · Cited by 1
Deterministic Quantum Mechanics – Part I – Conceptual FrameworkPreprint
Vadász, P. (2024) · Preprints.org · doi:10.20944/preprints202405.1244.v1 · Cited by 1
Quantum correlations and causal structures
Ibnouhsein, I. (2014) · theses.fr (ABES) · doi:10.70675/a546325bz1c6fz4174zaad3z9f5af10b4c2e · Cited by 1
Entanglement in Two and Three Quantum Mechanical Systems
Aguilar, L. M. A., Otero, M. M. M., & Mastranzo, P. (2012) · InTech eBooks · doi:10.5772/34900
Do entanglements need some superluminal hidden connection?Preprint
Wechsler, S. (2009) · arXiv (Cornell University) · doi:10.48550/arxiv.0905.0641
Suárez, A. (2008) · arXiv (Cornell University) · doi:10.48550/arxiv.0809.3502
On Bell's Joint Probability Distribution Assumption and Proposed Experiments of Quantum MeasurementPreprint
Zhao, H.-L. (2009) · arXiv (Cornell University)
Von Neumann’s Theory, Projective Measurement, and Quantum Computation
Nagata, K., & Nakamura, T. (2015) · Journal of Applied Mathematics and Physics · doi:10.4236/jamp.2015.37108
Emaranhamento multicor para redes de informação quântica
Coelho, A. S. (2013) · Digital Library of Theses and Dissertations (Universidade de São Paulo) · doi:10.11606/t.43.2013.tde-20052014-105215
Violation of an inequality in an experimental test of Leggett's non-local hidden variable theoryPreprint
Nauenberg, M. (2007) · arXiv (Cornell University) · doi:10.48550/arxiv.0710.3220
The basic Leggett inequalities don't contradict the quantum theory, neither the classical physicsPreprint
Wechsler, S. (2009) · arXiv (Cornell University) · doi:10.48550/arxiv.0912.0885
Emelyanov, S. A. (2014) · arXiv (Cornell University)
Correlações quânticas multicolores no oscilador paramétrico ótico
Cassemiro, K. N. (2008) · Digital Library of Theses and Dissertations (Universidade de São Paulo) · doi:10.11606/t.43.2008.tde-11062008-153347
UNTANGLING THE HARD PROBLEM OF CONSCIOUSNESS
Duncan, T. L. (2009)
Can Hidden Variables Theories Meet Quantum Computation?
Nagata, K., & Nakamura, T. (2015) · OALib · doi:10.4236/oalib.1101804
Physicists bid farewell to reality?
Ball, P. (2007) · Nature · doi:10.1038/news070416-9
AN INTERPLAY BETWEEN NONLOCALITY AND QUANTUM VIOLATION OF PATH–SPIN NONCONTEXTUALITY
Home, D., & Pan, A. K. (2011) · International Journal of Quantum Information · doi:10.1142/s0219749911007927
Temperature dependence of violation of Bell’s inequality in coupled quantum dots in a microcavity
Du, C.-R., & Zhu, K. (2009) · Applied Physics B · doi:10.1007/s00340-009-3536-6
Beyond Bell's theorem: Admissible hidden-variable models for the spin-singlet
Lorenzo, A. D. (2013) · Journal of Physics Conference Series · doi:10.1088/1742-6596/442/1/012046
Quantum Mechanics and Leggett’s Inequalities
Socolovsky, M. (2009) · International Journal of Theoretical Physics · doi:10.1007/s10773-009-0131-x
Solving the EPR paradox with pseudo-classical pathsPreprint
Oaknin, D. H. (2013) · arXiv (Cornell University) · doi:10.48550/arxiv.1306.5492
Commitment to “Forbidden Questions” in Quantum Phenomena Requires a Philosophical Stand
Ellias, J. (2013) · D-Scholarship@Pitt (University of Pittsburgh)
A Pragmatic Realism: Events, Powers, and Relations in the Metaphysics of Objective Relativism
Taylor, P. J. (2013) · PhilPapers (PhilPapers Foundation)
Pons, D. J., Pons, A. D., & Pons, A. J. (2015)
Whether the CPT Symmetry Can Be Almighty Even in a Photon
Nagata, K., & Nakamura, T. (2015) · OALib · doi:10.4236/oalib.1101806
CLASSICAL, QUANTUM AND SUPERQUANTUM CORRELATIONS
GHIRARDI, G., & ROMANO, R. (2012) · International Journal of Modern Physics B · doi:10.1142/s0217979213450112
Nonclassical correlations in the motion of dissociated Feshbach molecules
München, L.-M.-U. (2010)
Internal mechanics of pair production: Remanufacture of discrete fields in a NLHV design
Pons, D. J., Pons, A. D., & Pons, A. J. (2014)
On the Counter-Intuitiveness of Quantum Entanglement
Stanzl, R. (2012) · University of Vienna · doi:10.25365/thesis.20529
Scan Quantum Mechanics: Quantum Inertia Stops Superposition
Beatriz Gato-rivera, A. (2025) · Universe · doi:10.3390/universe11020058
applications in quantum information
Schmid, C. (2008)
A classical probability space exists for the measurement theory based on the truth values
Nagata, K., & Nakamura, T. (2016) · Quantum Studies Mathematics and Foundations · doi:10.1007/s40509-016-0083-9
Realization of a single-atom-like macroscopic system to test the foundations of quantum mechanics
Emelyanov, S. A., & Leggett, A. J. (2014)
Emelyanov, S. A. (2014) · arXiv (Cornell University)
42 Bell's Inequalities — Foundations and Quantum
Brukner, Č., & Żukowski, M. (2012)
Self-citationExperimental Quantum Information Processing with Photons
Lavoie, J. (2013) · UWSpace (University of Waterloo)
Quantum uncertainty and a counterexample of nonlocal classical “realism”
Belinsky, A. V. (2017) · Optics and Spectroscopy · doi:10.1134/s0030400x17090077
New Method of Obtaining the Kochen-Specker Theorem
Nagata, K., Nakamura, T., & Farouk, A. (2017) · Studies in big data · doi:10.1007/978-3-319-63639-9_12
Bernroider, G. (2017) · Journal of Integrative Neuroscience · doi:10.3233/jin-170071
Towards an Understanding of the Mutual Dependency of Consciousness and Matter
Lucido, R. J. (2018) · CIIS Digital Commons (California Institute of Integral Studies)
Zhao, H.-L. (2009) · arXiv (Cornell University) · doi:10.7868/s0044451013120031
The EPR-B Paradox Resolution. Bell inequalities revisited.
Foukzon, J., Романовна, М. Е., & Potapov, A. A. (2019) · Journal of Physics Conference Series · doi:10.1088/1742-6596/1391/1/012073
What is quantum information? Information symmetry and mechanical motionPreprint
Penchev, V. D. (2020) · SocArXiv (OSF Preprints) · doi:10.31235/osf.io/etp5f
CLASSICAL, QUANTUM AND SUPERQUANTUM CORRELATIONSPreprint
Ghirardi, G. C., & Romano, R. (2016)
Li, W., Liu, R., Li, J., Zhong, J., Chen, H., & Wang, X. (2021) · Research Square · doi:10.21203/rs.3.rs-228136/v1
Emelyanov, S. A. (2021) · arXiv (Cornell University) · doi:10.48550/arxiv.2106.11016
Leggett-type inequalities for testing nonlocal realism in multipartite systemsPreprint
Khan, A. S., Yang, M.-C., & Qiao, C. (2021) · arXiv (Cornell University) · doi:10.48550/arxiv.2108.03665
On Quantum Gravity as a Recorded Quantum Arrow of TimePreprint
Kauffman, S. A. (2021) · arXiv (Cornell University)
Uma discussão sobre os problemas da completude, da não-localidade e do realismo na teoria quântica
Souza, R. D. S., Silva, I. L., & Teixeira, E. S. (2020) · Revista Brasileira de História da Ciência · doi:10.53727/rbhc.v13i2.30
Calcul quantique : algèbre et géométrie projective
Baboin, A.-C. (2011) · theses.fr (ABES) · doi:10.70675/c1d24edfz6e2cz4987zaf6azf07a56ddee4c
The EPR Paradox Resolution. The Bell Inequalities RevisitedPreprint
Foukzon, J., Men’kova, E. R., & Potapov, A. A. (2021) · SSRN Electronic Journal · doi:10.2139/ssrn.3332723
Química de la información: aspectos clásicos y cuánticos de fenómenos moleculares
Espíritu, G. M. M. (2015) · doi:10.24275/uami.5t34sj69w
Breaking the Frame of Digital, Dream, and Waking Realities
Gackenbach, J., & Hakopdjanian, S. (2018) · IGI Global eBooks · doi:10.4018/978-1-5225-5469-1.ch067
(2022) · SciPost Physics Core · doi:10.21468/scipost.report.4234
(2022) · SciPost Physics Core · doi:10.21468/scipost.report.4140
(2022) · SciPost Physics Core · doi:10.21468/scipost.report.4816
(2022) · SciPost Physics Core · doi:10.21468/scipost.report.4635
(2008) · Nachrichten aus der Chemie · doi:10.1002/nadc.200858497
Verschränkung und Nicht-Lokalität: EPR, Bell und die Folgen
Näger, P. M., & Stöckler, M. (2014) · Springer eBooks · doi:10.1007/978-3-642-37790-7_4
The GHZ Theorem Revisited within the Framework of Gauge Theory
Oaknin, D. H. (2023) · Symmetry · doi:10.3390/sym15071327
Deterministic Quantum Mechanics – Part I – Conceptual FrameworkPreprint
Vadász, P. (2024) · SSRN Electronic Journal · doi:10.2139/ssrn.4823460
Quantum Cosmology: The Integration of Special Relativity and Quantum Mechanics - Part 1Preprint
Kahan, D. (2024) · OSF Preprints (OSF Preprints) · doi:10.31219/osf.io/buf6c
Quantum Cosmology: The Integration of Special Relativity and Quantum Mechanics Part IPreprint
Kahan, D. (2024) · Preprints.org · doi:10.20944/preprints202405.2028.v2
Manifestation of strong and ultra-strong coupling in high-order correlation functions
Belashov, A. S., Andrianov, E. S., & Zyablovsky, A. A. (2024) · Journal of the Optical Society of America B · doi:10.1364/josab.524077
Metadata
- Authors
- Gröblacher, S., Paterek, T., Kaltenbaek, R., Brukner, Č., Żukowski, M., Aspelmeyer, M., & Zeilinger, A.
- Affiliations
- University of Vienna (AT)
- University of Gdańsk (PL)
- Corresponding author
- Aspelmeyer, Markus
- Zeilinger, Anton
- ORCID
- Venue
- Nature
- Published
- 2007-04-19
- Volume
- 446
- Issue
- 7138
- Pages
- 871-875
- ISSN
- 0028-0836 (ISSN-L)
- 1476-4687
- OpenAlex
- W2082420839
- Cited by
- 419
- References
- 35
- Citations by year
- 2026: 5 · 2025: 20 · 2024: 17 · 2023: 13 · 2022: 18 · 2021: 14 · 2020: 14 · 2019: 13 · 2018: 17 · 2017: 25 · 2016: 23 · 2015: 24 · 2014: 27 · 2013: 32 · 2012: 26
- FWCI
- 23.05
- Type
- journal article
- Language
- en
- Update notices
- erratum (2007-09-13)
- Open access
- green
- arxiv.org
- Locations
- Nature (publishedVersion)
- PubMed (publishedVersion)
- arXiv (Cornell University) (submittedVersion)
- RePEc: Research Papers in Economics (submittedVersion)
- arXiv (Cornell University)
- Topics
- Physical Sciences › Physics and Astronomy › Atomic and Molecular Physics, and Optics › Quantum Mechanics and Applications
- Physical Sciences › Physics and Astronomy › Atomic and Molecular Physics, and Optics › Quantum Information and Cryptography
- Physical Sciences › Physics and Astronomy › Nuclear and High Energy Physics › Noncommutative and Quantum Gravity Theories
- Keywords
- Bell's theorem, quantum correlations, entangled photons, locality, realism, quantum foundations, hidden variable theories, quantum nonlocality
About these checks
Registry, retraction, Cites and statistics results are computed, not judged, with one exception: a printed reference that no index lists is read once by a model before it counts as a citation error. Claims are extracted by a model and kept only when their quote appears verbatim in the text; each cited source is then checked, with a model’s help, for whether it says what the claim relies on. Those verdicts can be wrong — read the claim’s quote and the cited source before relying on one.
Statistics and arithmetic are recomputed, not judged.
Confidence bands are shown only for fields calibrated on our annotated test set. None is calibrated yet, so no band is shown.
What counts as a claim ›How we measure confidence ›How we check this ›
Are you an author, or do you see a problem with this page? Request a review
