Entanglement: quantum or classical?

  title={Entanglement: quantum or classical?},
  author={Dilip Paneru and Eliahu Cohen and Robert Fickler and Robert W. Boyd and Ebrahim Karimi},
  journal={Reports on Progress in Physics},
From its seemingly non-intuitive and puzzling nature, most evident in numerous EPR-like gedanken experiments to its almost ubiquitous presence in quantum technologies, entanglement is at the heart of modern quantum physics. First introduced by Erwin Schrödinger nearly a century ago, entanglement has remained one of the most fascinating ideas that came out of quantum mechanics. Here, we attempt to explain what makes entanglement fundamentally different from any classical phenomenon. To this end… 
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