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arXiv · 2103.16390

A note about claw function with a small range

Andris Ambainis·Kaspars Balodis·Jānis Iraids
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Abstract

In the claw detection problem we are given two functions $f:D\rightarrow R$ and $g:D\rightarrow R$ ($|D|=n$, $|R|=k$), and we have to determine if there is exist $x,y\in D$ such that $f(x)=g(y)$. We show that the quantum query complexity of this problem is between $\Omega\left(n^{1/2}k^{1/6}\right)$ and $O\left(n^{1/2+\varepsilon}k^{1/4}\right)$ when $2\leq k<n$.

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Andris Ambainis, Kaspars Balodis, Jānis Iraids. 2021-03-30. A note about claw function with a small range. https://arxiv.org/abs/2103.16390

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