Kloosterman paths of prime powers moduli

In their joint work Kloosterman paths and the shape of exponential sums published 2016, Kowlaski & Sawin proved, using a deep independence result of Kloosterman sheaves, that the polygonal paths joining the partial sums of the normalized classical Kloosterman sums $S(a,b_0;p)/p^{1/2}$ converge in the sense of finite distributions to a specific random Fourier series, as $a$ varies over $(\mathbb{Z}/p\mathbb{Z})^{\times}$ and $p$ tends to infinity among the odd prime numbers. This article considers the case of $S(a,b_0;p)/p^{1/2}$ as $a$ varies over $(\mathbb{Z}/p^n\mathbb{Z})^{\times}$, $b_0$ is fixed in $(\mathbb{Z}/p^n\mathbb{Z})^{\times}$ $p$ tends to infinity among the odd prime numbers and $n>1$ is a fixed integer. A convergence in law in the Banach space of complex-valued continuous function on $[0,1]$ is also established, as $(a,b)$ varies over $(\mathbb{Z}/p^n\mathbb{Z})^{\times}\times(\mathbb{Z}/p^n\mathbb{Z})^{\times}$ $p$ tends to infinity among the odd prime numbers and $n>1$ is a fixed integer. This is the analogue of the result obtained by Kowlaski & Sawin in the prime moduli case.

Article de revue

Commentarii Mathematici Helvetici 93, No. 3, 493-532