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Quantum Verification of Matrix Products

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 نشر من قبل Robert Spalek
 تاريخ النشر 2004
  مجال البحث فيزياء
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We present a quantum algorithm that verifies a product of two n*n matrices over any field with bounded error in worst-case time n^{5/3} and expected time n^{5/3} / min(w,sqrt(n))^{1/3}, where w is the number of wrong entries. This improves the previous best algorithm that runs in time n^{7/4}. We also present a quantum matrix multiplication algorithm that is efficient when the result has few nonzero entries.



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