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Quantum physics

Entangled quartet

Quantum physics is known for its counter-intuitive principles. One such principle — that a single photon can be in as many as four places at the same time — has now been demonstrated. See Letter p.412

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Figure 1: Particle-type versus wave-type measurements.


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Vuletic, V. Entangled quartet. Nature 468, 384–385 (2010).

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