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Quantum computers can search rapidly by using almost any transformation

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 نشر من قبل Lov K. Grover
 تاريخ النشر 1997
  مجال البحث فيزياء
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 تأليف Lov K. Grover




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A quantum computer has a clear advantage over a classical computer for exhaustive search. The quantum mechanical algorithm for exhaustive search was originally derived by using subtle properties of a particular quantum mechanical operation called the Walsh-Hadamard (W-H) transform. This paper shows that this algorithm can be implemented by replacing the W-H transform by almost any quantum mechanical operation. This leads to several new applications where it improves the number of steps by a square-root. It also broadens the scope for implementation since it demonstrates quantum mechanical algorithms that can readily adapt to available technology.



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