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A Photonic System for Generating Unconditional Polarization-Entangled Photons Based on Multiple Quantum Interference
Published on: September 5, 2019
All bipartite entangled States display some hidden nonlocality
Lluís Masanes1, Yeong-Cherng Liang, Andrew C Doherty
1School of Mathematics, University of Bristol, Bristol BS8 1TW, United Kingdom.
Physical Review Letters
|March 21, 2008
Summary
All entangled quantum states can violate Bell inequalities, demonstrating nonlocality. Researchers characterized states that don't violate the Clauser-Horne-Shimony-Holt (CHSH) inequality and proved all entangled states can exhibit nonlocality.
Area of Science:
- Quantum Information Science
- Quantum Foundations
- Quantum Entanglement
Background:
- Entangled states are known for violating Bell inequalities, challenging local-realistic theories.
- The exact relationship between entanglement and observable nonlocality remains unclear.
- Some entangled states do not violate Bell inequalities.
Purpose of the Study:
- To demonstrate that all entangled states can violate the Clauser-Horne-Shimony-Holt (CHSH) inequality.
- To characterize states that do not violate the CHSH inequality under local operations and classical communication.
- To establish a clear link between entanglement and observable nonlocality.
Main Methods:
- Characterizing the set of states that resist CHSH inequality violation after local operations and classical communication.
- Proving the existence of a non-CHSH-violating state whose combination with any entangled state leads to CHSH violation.
Main Results:
- A method to characterize states that do not violate the CHSH inequality is provided.
- It is proven that for any entangled state, a CHSH-violating state can be constructed.
- All entangled states are shown to be capable of demonstrating nonlocality via CHSH inequality violation.
Conclusions:
- The study clarifies the relationship between entanglement and nonlocality.
- All entangled states can exhibit observable nonlocality in Bell experiments.
- This work provides a comprehensive understanding of entanglement and Bell inequality violations.
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