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arXiv · 2406.06956

Arbitrarily slow decay in the logarithmically averaged Sarnak conjecture

Amir Algom·Zhiren Wang
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Abstract

In 2017 Tao proposed a variant Sarnak's M\"{o}bius disjointness conjecture with logarithmic averaging: For any zero entropy dynamical system $(X,T)$, $\frac{1}{\log N} \sum_{n=1} ^N \frac{f(T^n x) \mu (n)}{n}= o(1)$ for every $f\in \mathcal{C}(X)$ and every $x\in X$. We construct examples showing that this $o(1)$ can go to zero arbitrarily slowly. Nonetheless, all of our examples satisfy the conjecture.

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Amir Algom, Zhiren Wang. 2024-06-11. Arbitrarily slow decay in the logarithmically averaged Sarnak conjecture. https://arxiv.org/abs/2406.06956

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