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arXiv · 1810.01790

A note on the quantum query complexity of permutation symmetric functions

André Chailloux
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Abstract

It is known since the work of [AA14] that for any permutation symmetric function $f$, the quantum query complexity is at most polynomially smaller than the classical randomized query complexity, more precisely that $R(f) = \widetilde{O}\left(Q^7(f)\right)$. In this paper, we improve this result and show that $R(f) = {O}\left(Q^3(f)\right)$ for a more general class of symmetric functions. Our proof is constructive and relies largely on the quantum hardness of distinguishing a random permutation from a random function with small range from Zhandry [Zha15].

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André Chailloux. 2018-10-03. A note on the quantum query complexity of permutation symmetric functions. https://arxiv.org/abs/1810.01790

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