ObsidianVault/SS2026/Quantum Computing/10. Discrete Fourier Transformation/Discrete Fourier Transformation.md at 4a0e3a6e22b48e4307f7ff27f261bbe3c720a3ed

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2026-07-30 19:06:10 +02:00

A mathematical technique that decomposes a function into its constituent frequencies.

Definition

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The transformation is a process that takes a periodic vector as an input and outputs the period of that vector.

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We will now model DFT as a quantum circuit. For this we only look at N = 2^n, DFT applied on n qubits.

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Let us look at an example DFT for n = 3: ! Pasted image 20260730183136.png ! Pasted image 20260730183145.png

The more general approach works as follows:

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