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Bounding the set of classical correlations of a many-body system

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 نشر من قبل Jordi Tura
 تاريخ النشر 2017
  مجال البحث فيزياء
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We present a method to certify the presence of Bell correlations in experimentally observed statistics, and to obtain new Bell inequalities. Our approach is based on relaxing the conditions defining the set of correlations obeying a local hidden variable model, yielding a convergent hierarchy of semidefinite programs (SdPs). Because the size of these SdPs is independent of the number of parties involved, this technique allows to characterize correlations in many-body systems. As an example, we illustrate our method with the experimental data presented in [Science 352, 441 (2016)]



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