We start this project by describing the quantum model on which the quantum computation theory has been built. The main part of this project has to do with the Fourier transform on finite abelian groups and its use in P.Shor0s quantum algorithm for factorizing integers in polynomial time. As well, we describe L.Grover0s quantum algorithm for searching an element in an unstructured database of N elements (which is of order O(pN)) and we prove that Grover0s algorithm is optimal.
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