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arXiv · 2207.09922

The finite Fourier Transform and projective 2-designs

Gerhard Zauner
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Abstract

There are several approaches to define an eigenvector decomposition of the finite Fourier Transform, which is in some sense unique, and at best resembles the eigenstates of the quantum harmonic oscillator. A solution given by Balian and Itzykson in 1986 for prime dimensions d = 3 (mod 4) is revisited. It is shown, that by applying the Weyl-Heisenberg matrices to this eigenvector basis, a projective 2-design is generated.

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Gerhard Zauner. 2022-07-20. The finite Fourier Transform and projective 2-designs. https://arxiv.org/abs/2207.09922

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