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arXiv · 2406.11529

Fourier transform in cyclic groups

Yves Benoist
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Abstract

On a cyclic group of prime order, the non-trivial Dirichlet characters together with their Fourier transforms have constant modulus outside 0 and vanish at 0. Answering a question of H. Cohn, we construct new functions with these properties. The proof relies on Floer homology. We also apply this method to the biunimodular functions problem.

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Yves Benoist. 2024-06-17. Fourier transform in cyclic groups. https://arxiv.org/abs/2406.11529

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