An experimental test of non-local realism

  title={An experimental test of non-local realism},
  author={Simon Gr{\"o}blacher and Tomasz Paterek and Rainer Kaltenbaek and {\vC}aslav Brukner and Marek Żukowski and Markus Aspelmeyer and Anton Zeilinger},
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… Expand
Quantum mechanics: To be or not to be local
A new study combing experiment and theory shows that a broad and rather reasonable class of such non-local realistic theories is incompatible with observed quantum correlations, suggesting that any future extension of quantum theory must abandon certain features of realistic descriptions. Expand
How Quantum is the Classical World
Background: Experiment has confirmed that quantum phenomena can violate the Information Bell Inequalities. A violation of the one or the other of these inequalites is equivaent to a violation ofExpand
A Physical Basis for Entanglement in a Non-Local Hidden Variable Theory
Problem: Superposition and entanglement are coherent effects, which can be quantified by quantum mechanics (QM), but lack descriptive explanations. They are typically analysed with inequalityExpand
An experimental test of all theories with predictive power beyond quantum theory
According to quantum theory, the outcomes of future measurements cannot (in general) be predicted with certainty. In some cases, even with a complete physical description of the system to be measuredExpand
A non-local hidden-variable model that violates Leggett-type inequalities
Recent experiments of Groblacher et al proved the violation of a Leggett-type inequality that was claimed to be valid for a broad class of non-local hidden-variable theories. The impossibility ofExpand
Probing the Completeness of Quantum Theory with Entangled Photons
Quantum theory provides a way to describe the behaviour of matter and energy on the nano-scale, but its predictions are sometimes very surprising. Intuition, based on experience from our daily lives,Expand
Quantum nonlocality does not demand all-out randomness in measurement choice
Nonlocality is the most characteristic feature of quantum mechanics. John Bell, in his seminal 1964 work, proved that local-realism imposes a bound on the correlations among the measurementExpand
Extending quantum mechanics entails extending special relativity
The complementarity between signaling and randomness in any communicated resource that can simulate singlet statistics is generalized by relaxing the assumption of free will in the choice ofExpand
Entanglement and Non-locality: EPR, Bell and Their Consequences
Entangled states are a specific feature of quantum physics that neither have a counterpart in classical physics nor in the realm of our ordinary experiences. In this chapter we outline the debateExpand
Testing Leggett's Inequality Using Aharonov-Casher Effect
In this work, four entangled particles emitted from two sources manifest a two-qubit-typed correlation that may result in the violation of the Leggett inequality, while satisfying the no-signaling condition for spacelike separation, in a scheme tolerant to some local inaccuracies due to the topological nature of the Aharonov-Casher phase. Expand


Experimental violation of a Bell's inequality with efficient detection
Here, correlations in the classical properties of massive entangled particles (9Be+ ions): these correlations violate a form of Bell's inequality, and the high detection efficiency of the apparatus eliminates the so-called ‘detection’ loophole. Expand
Experimental test of quantum nonlocality in three-photon Greenberger–Horne–Zeilinger entanglement
Experimental confirmation of Bell's theorem is reported, using the recently developed method to observe three-photon entanglement, or ‘Greenberger–Horne–Zeilinger’ (GHZ) states, and finds the results of the fourth experiment to be in agreement with the quantum prediction and in striking conflict with local realism. Expand
Nonlocal Hidden-Variable Theories and Quantum Mechanics: An Incompatibility Theorem
It is argued that among possible nonlocal hidden-variable theories a particular class (called here “crypto-nonlocal” or CN) is relatively plausible on physical grounds. CN theories have the propertyExpand
Bell's theorem. Experimental tests and implications
Bell's theorem represents a significant advance in understanding the conceptual foundations of quantum mechanics. The theorem shows that essentially all local theories of natural phenomena that areExpand
The problems in quantum foundations in the light of gauge theories
We review the issues of nonseparability and seemingly acausal propagation of information in EPR, as displayed by experiments and the failure of Bell's inequalities. We show that global effects are inExpand
In this paper, we shall show how the theory of measurements is to be understood from the point of view of a physical interpretation of the quantum theory in terms of hidden variables developed in aExpand
Bell's theorem, quantum theory and conceptions of the universe
On a Theory of the Collapse of the Wave Function.- On the Measurement Problem of Quantum Mechanics.- A New Characteristic of a Quantum System Between Two Measurements - A "Weak Value".- Can theExpand
Bell’s theorem without inequalities
It is demonstrated that the premisses of the Einstein–Podolsky–Rosen paper are inconsistent when applied to quantum systems consisting of at least three particles. The demonstration reveals that theExpand
Can Quantum-Mechanical Description of Physical Reality Be Considered Complete?
Consideration of the problem of making predictions concerning a system on the basis of measurements made on another system that had previously interacted with it leads to the result that one is led to conclude that the description of reality as given by a wave function is not complete. Expand
Going Beyond Bell’s Theorem
Bell’s Theorem proved that one cannot in general reproduce the results of quantum theory with a classical, deterministic local model. However, Einstein originally considered the case where one couldExpand