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Experimental Limits of Ghost Diffraction: Popper's Thought Experiment.

ABSTRACT: Quantum ghost diffraction harnesses quantum correlations to record diffraction or interference features using photons that have never interacted with the diffractive element. By designing an optical system in which the diffraction pattern can be produced by double slits of variable width either through a conventional diffraction scheme or a ghost diffraction scheme, we can explore the transition between the case where ghost diffraction behaves as conventional diffraction and the case where it does not. For conventional diffraction the angular extent increases as the scale of the diffracting object is reduced. By contrast, we show that no matter how small the scale of the diffracting object, the angular extent of the ghost diffraction is limited (by the transverse extent of the spatial correlations between beams). Our study is an experimental realisation of Popper's thought experiment on the validity of the Copenhagen interpretation of quantum mechanics. We discuss the implication of our results in this context and explain that it is compatible with, but not proof of, the Copenhagen interpretation.

SUBMITTER: Moreau PA

PROVIDER: S-EPMC6123420 | biostudies-literature | 2018 Sep

REPOSITORIES: biostudies-literature

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Experimental Limits of Ghost Diffraction: Popper's Thought Experiment.

Moreau Paul-Antoine PA Morris Peter A PA Toninelli Ermes E Gregory Thomas T Aspden Reuben S RS Spalding Gabriel G Boyd Robert W RW Padgett Miles J MJ

Scientific reports 20180904 1

Quantum ghost diffraction harnesses quantum correlations to record diffraction or interference features using photons that have never interacted with the diffractive element. By designing an optical system in which the diffraction pattern can be produced by double slits of variable width either through a conventional diffraction scheme or a ghost diffraction scheme, we can explore the transition between the case where ghost diffraction behaves as conventional diffraction and the case where it do ...[more]

PMID: 30181599

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Experimental Limits of Ghost Diffraction: Popper's Thought Experiment.

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Experimental Limits of Ghost Diffraction: Popper's Thought Experiment.

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