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Is macroscopic entanglement a typical trait of many-particle quantum states?

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 نشر من قبل Malte Tichy
 تاريخ النشر 2015
  مجال البحث فيزياء
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We elucidate the relationship between Schrodinger-cat-like macroscopicity and geometric entanglement, and argue that these quantities are not interchangeable. While both properties are lost due to decoherence, we show that macroscopicity is rare in uniform and in so-called random physical ensembles of pure quantum states, despite possibly large geometric entanglement. In contrast, permutation-symmetric pure states feature rather low geometric entanglement and strong and robust macroscopicity.



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