# Loophole-free Bell inequality violation using electron spins separated by 1.3 kilometres

@article{Hensen2015LoopholefreeBI, title={Loophole-free Bell inequality violation using electron spins separated by 1.3 kilometres}, author={Bas Hensen and Hannes Bernien and Ana{\"i}s Dr{\'e}au and Andreas Reiserer and Norbert Kalb and Machiel S. Blok and J. Ruitenberg and R. F. L. Vermeulen and R. N. Schouten and Carlos Abell{\'a}n and Waldimar Amaya and Valerio Pruneri and Morgan W. Mitchell and Matthew L. Markham and Daniel J. Twitchen and David Elkouss and Stephanie Wehner and T H Taminiau and Ronald Hanson}, journal={Nature}, year={2015}, volume={526}, pages={682-686} }

More than 50 years ago, John Bell proved that no theory of nature that obeys locality and realism can reproduce all the predictions of quantum theory: in any local-realist theory, the correlations between outcomes of measurements on distant particles satisfy an inequality that can be violated if the particles are entangled. Numerous Bell inequality tests have been reported; however, all experiments reported so far required additional assumptions to obtain a contradiction with local realism…

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