Testing the speed of ‘spooky action at a distance’

  title={Testing the speed of ‘spooky action at a distance’},
  author={Daniel Salart and Augustin Baas and Cyril Branciard and Nicolas Gisin and Hugo Zbinden},
Correlations are generally described by one of two mechanisms: either a first event influences a second one by sending information encoded in bosons or other physical carriers, or the correlated events have some common causes in their shared history. Quantum physics predicts an entirely different kind of cause for some correlations, named entanglement. This reveals itself in correlations that violate Bell inequalities (implying that they cannot be described by common causes) between space-like… 
Comment on: Testing the speed of 'spooky action at a distance'
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