Failure of Local Realism Revealed by Extremely Coarse-Grained Measurements

Abstract

We show that failure of local realism can be revealed to observers for whom only extremely coarse-grained measurements are available. In our instances, Bell's inequality is violated even up to the maximum limit while both the local measurements and the initial local states under scrutiny approach the classical limit. Furthermore, we can observe failure of local realism when an inequality enforced by non-local realistic theories is satisfied. This suggests that locality alone may be violated while realism cannot be excluded for specific observables and states. Small-scale experimental demonstration of our examples may be possible in the foreseeable future.

arXiv comment4 pages, 3 figures, RevTeX4

References in corpus (17)

• Decoherence, einselection, and the quantum origins of the classical
• An experimental test of non-local realism
• Efficient Quantum Computation using Coherent States
• Nonlocality of Einstein-Podolsky-Rosen State in Wigner Representation
• Classical world arising out of quantum physics under the restriction of coarse-grained measurements
• Maximal Violation of Bell's Inequalities for Continuous Variable Systems
• Using weak nonlinearity under decoherence for macroscopic-entanglement generation and quantum computation
• Testing quantum correlations versus single-particle properties within Leggett's model and beyond
• Experimental Falsification of Leggett's Non-Local Variable Model
• Experimental test of nonlocal realistic theories without the rotational symmetry assumption
• Violation of Bell's inequality using classical measurements and non-linear local operations
• Transfer of Nonclassical Properties from A Microscopic Superposition to Macroscopic Thermal States in The High Temperature Limit
• Tailoring optical nonlinearities via the Purcell effect
• Quantum superpositions and entanglement of thermal states at high temperatures and their applications to quantum information processing
• Decoherence of Highly Mixed Macroscopic Quantum Superpositions
• Bell-inequality violation with "thermal" radiation
• Entanglement of mixed macroscopic superpositions: an entangling-power study

Cited by in corpus (43)

• Macroscopic quantum states: measures, fragility and implementations
• Quantification of Macroscopic Quantum Superpositions within Phase Space
• Qubit-assisted thermometry of a quantum harmonic oscillator
• Coarsening Measurement References and the Quantum-to-Classical Transition
• Coarse Graining Makes It Hard to See Micro-Macro Entanglement
• Violation of Bell-CHSH inequality using imperfect photodetectors with optical hybrid states
• Investigating macroscopic quantum superpositions and the quantum-to-classical transition by optical parametric amplification
• Characterizations and Quantifications of Macroscopic Quantumness and Its Implementations using Optical Fields
• Generating a Schrödinger-cat-like state via a coherent superposition of photonic operations
• Testing non-local realism with entangled coherent states
• Quantum to classical transition via fuzzy measurements on high gain spontaneous parametric down-conversion
• Faithful test of non-local realism with entangled coherent states
• Entangled coherent states versus entangled photon pairs for practical quantum information processing
• Hybrid methods for witnessing entanglement in a microscopic-macroscopic system
• Creating and detecting micro-macro photon-number entanglement by amplifying and de-amplifying a single-photon entangled state
• Non-classicality of optomechanical devices in experimentally realistic operating regimes
• Efficient noiseless linear amplification for light fields with larger amplitudes
• Quantum mechanical violation of macrorealism for large spin and its robustness against coarse-grained measurements
• Using macroscopic entanglement to close the detection loophole in Bell inequality
• Effects of squeezing on quantum nonlocality of superpositions of coherent states
• Two proposals for testing quantum contextuality of continuous-variable states
• Bell inequality tests using asymmetric entangled coherent states in asymmetric lossy environments
• Detecting the degree of macroscopic quantumness using an overlap measurement
• Violation of Bell inequalities in larger Hilbert spaces: robustness and challenges
• Bell inequality test with entanglement between an atom and a coherent state in a cavity
• Violation of Bell's inequalities with pre-amplified homodyne detection
• Genuine multipartite nonlocality of entangled thermal states
• Macroscopic delayed-choice and retrocausality: quantum eraser, Leggett-Garg and dimension witness tests with cat states
• Generation of distributed entangled coherent states over a lossy environment with inefficient detectors
• Towards loophole-free Bell inequality test with preselected unsymmetrical singlet states of light
• Persistence of quantum violation of macrorealism for large spins even under coarsening of measurement times
• Non-Markovian effects on non-locality of a qubit-oscillator system
• Mesoscopic and macroscopic quantum correlations in photonic, atomic and optomechanical systems
• Nonlinear Bell inequality for macroscopic measurements
• Correlations in local measurements and entanglement in many-body systems
• Weak versus deterministic macroscopic realism, and Einstein-Podolsky-Rosen's elements of reality
• Noise-adaptive test of quantum correlations with quasiprobability functions
• How Quantum is the Classical World?
• Forward-backward stochastic simulations: Q-based model for measurement and Bell-nonlocality consistent with weak local realistic premises
• Degree of Fuzziness in Coarsened Measurement References
• Production of entanglement with highly-mixed states
• Gravitational time dilation induced decoherence during spontaneous emission
• Light polarization measurements in tests of macrorealism