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arXiv · 2106.09800

Pair Correlation of the Fractional Parts of $\alpha n^\theta$

Christopher Lutsko·Athanasios Sourmelidis·Niclas Technau
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Abstract

Fix $\alpha,\theta >0$, and consider the sequence $(\alpha n^{\theta} \mod 1)_{n\ge 1}$. Since the seminal work of Rudnick--Sarnak (1998), and due to the Berry--Tabor conjecture in quantum chaos, the fine-scale properties of these dilated mononomial sequences have been intensively studied. In this paper we show that for $\theta \le 1/3$, and $\alpha>0$, the pair correlation function is Poissonian. While (for a given $\theta \neq 1$) this strong pseudo-randomness property has been proven for almost all values of $\alpha$, there are next-to-no instances where this has been proven for explicit $\alpha$. Our result holds for all $\alpha>0$ and relies solely on classical Fourier analytic techniques. This addresses (in the sharpest possible way) a problem posed by Aistleitner--El-Baz--Munsch (2021).

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Christopher Lutsko, Athanasios Sourmelidis, Niclas Technau. 2021-06-17. Pair Correlation of the Fractional Parts of $\alpha n^\theta$. https://arxiv.org/abs/2106.09800

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