Quantum Entanglement: from Popper’s Experiment to Quantum Eraser
Uncertainty, being perhaps the most basic principle of quantum mechanics, distinguishes the world of quantum phenomena from the realm of classical physics. Quantum entanglement, being perhaps the most surprising consequence of quantum mechanics, on the other hand apparently suggests paradoxes relating to or violations of the quantum mechanical uncertainty principle in some experimental situations. Popper’s experiment and quantum eraser are two examples. Is this a paradox? Are we confronted by a violation of the uncertainty principle? These questions are addressed in this paper.
KeywordsUncertainty Principle Quantum Entanglement Ghost Image Joint Detection Optical Distance
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