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Chap 5 Q Fourier Transform : p 216-247. Avery Leider The information presented here, although greatly condensed, comes almost entirely from the course textbook: Quantum Computation and Quantum Information by Nielsen & Chuang and the tutorials written by Prof Ronald Frank.
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Chap 5 Q Fourier Transform: p 216-247 Avery Leider The information presented here, although greatly condensed, comes almost entirely from the course textbook: Quantum Computation and Quantum Information by Nielsen & Chuang and the tutorials written by Prof Ronald Frank
5.1 Why the investment in Quantum Computing? • Prime factorization of an n-bit integer on a classical computer using the number field sieve: • Same task with a quantum algorithm: Quantum is faster!
Military Applications Quantum Computing
5.1 Quantum Fourier Transform • Quantum Fourier Transform is an algorithm used in • quantum factoring of primes, • and other quantum algorithms. • Useful for warfare. Quantum Computing
Fourier seriesillustration by Pierre Guilleminot • https://bl.ocks.org/jinroh/7524988 Research Seminar 1 Review
5.1 Quantum Fourier Transform From Box 5.1 on page 220 of Nielsen, M.A. and Chuang, I., 2002. Quantum computation and quantum information. Quantum Computing
5.2 Quantum Phase Estimation algorithm • Phase Estimation uses the inverse Quantum Fourier transform • Phase Estimation makes it possible to estimate the phase that a unitary transformation adds to one of its eigenvectors.
Quantum Phase Estimation • Phase Estimation is a subroutine that prepares an eigenstate of the Hermitian operator in one register • It stores the corresponding eigenvalue in a 2nd register • It uses momentum and phase shifts • & inverse Quantum Fourier transform https://quantumexperience.ng.bluemix.net/proxy/tutorial/full-user-guide/004-Quantum_Algorithms/100-Quantum_Phase_Estimation.html Quantum Computing
Phase Estimation Quantum Computing
Phase Estimation Research Seminar 1 Review
Phase Estimation • Phase Estimation, combined with quantum search algorithm, can solve the problem of counting solutions to a search problem. • Phase Estimation supports solutions to the order-finding problem and the factoring problem. Research Seminar 1 Review
5.4 General Applications of the quantum Fourier transform • Period finding • Discrete logarithms • Hidden subgroup problem • Other quantum algorithms? Quantum Computing
5.4 General Applications of the quantum Fourier transform • Quantum Computing can solve some problems exponentially better than classical computers. • Other problems it is polynominally better. • Quantum Fourier Transform is involved in most of these advantages • But in some cases, it is not any better. Quantum Computing