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All Quantum Adversary Methods are Equivalent

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 نشر من قبل Robert Spalek
 تاريخ النشر 2004
  مجال البحث فيزياء
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 تأليف Robert Spalek




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The quantum adversary method is one of the most versatile lower-bound methods for quantum algorithms. We show that all known variants of this method are equivalent: spectral adversary (Barnum, Saks, and Szegedy, 2003), weighted adversary (Ambainis, 2003), strong weighted adversary (Zhang, 2005), and the Kolmogorov complexity adversary (Laplante and Magniez, 2004). We also pa few new equivalent formulations of the method. This shows that there is essentially _one_ quantum adversary method. From our approach, all known limitations of the



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