Large odd order character sums and improvements of the Pólya-Vinogradov inequality

Author:

Lamzouri Youness,Mangerel Alexander

Abstract

For a primitive Dirichlet character χ \chi modulo q q , we define M ( χ ) = max t | n t χ ( n ) | M(\chi )=\max _{t } |\sum _{n \leq t} \chi (n)| . In this paper, we study this quantity for characters of a fixed odd order g 3 g\geq 3 . Our main result provides a further improvement of the classical Pólya-Vinogradov inequality in this case. More specifically, we show that for any such character χ \chi we have M ( χ ) ε q ( log q ) 1 δ g ( log log q ) 1 / 4 + ε , \begin{equation*} M(\chi )\ll _{\varepsilon } \sqrt {q}(\log q)^{1-\delta _g}(\log \log q)^{-1/4+\varepsilon }, \end{equation*} where δ g 1 g π sin ( π / g ) \delta _g ≔1-\frac {g}{\pi }\sin (\pi /g) . This improves upon the works of Granville and Soundararajan [J. Amer. Math. Soc. 20 (2007), pp. 357–384] and of Goldmakher [Algebra Number Theory 6 (2012), pp. 123–163]. Furthermore, assuming the Generalized Riemann Hypothesis (GRH) we prove that M ( χ ) q ( log 2 q ) 1 δ g ( log 3 q ) 1 4 ( log 4 q ) O ( 1 ) , \begin{equation*} M(\chi ) \ll \sqrt {q} \left (\log _2 q\right )^{1-\delta _g} \left (\log _3 q\right )^{-\frac {1}{4}}\left (\log _4 q\right )^{O(1)}, \end{equation*} where log j \log _j is the j j -th iterated logarithm. We also show unconditionally that this bound is best possible (up to a power of log 4 q \log _4 q ). One of the key ingredients in the proof of the upper bounds is a new Halász-type inequality for logarithmic mean values of completely multiplicative functions, which might be of independent interest.

Funder

Natural Sciences and Engineering Research Council of Canada

Publisher

American Mathematical Society (AMS)

Subject

Applied Mathematics,General Mathematics

Reference19 articles.

1. Multiplicative functions in arithmetic progressions;Balog, Antal;Ann. Math. Qu\'{e}.,2013

2. Pólya-Vinogradov and the least quadratic nonresidue;Bober, Jonathan W.;Math. Ann.,2016

3. Le grand crible dans la théorie analytique des nombres;Bombieri, Enrico;Ast\'{e}risque,1987

4. Graduate Texts in Mathematics;Davenport, Harold,2000

5. Improving the Burgess bound via Pólya-Vinogradov;Fromm, Elijah;Proc. Amer. Math. Soc.,2019

Cited by 1 articles. 订阅此论文施引文献 订阅此论文施引文献,注册后可以免费订阅5篇论文的施引文献,订阅后可以查看论文全部施引文献

1. Large sums of high‐order characters;Journal of the London Mathematical Society;2023-12-19

同舟云学术

1.学者识别学者识别

2.学术分析学术分析

3.人才评估人才评估

"同舟云学术"是以全球学者为主线,采集、加工和组织学术论文而形成的新型学术文献查询和分析系统,可以对全球学者进行文献检索和人才价值评估。用户可以通过关注某些学科领域的顶尖人物而持续追踪该领域的学科进展和研究前沿。经过近期的数据扩容,当前同舟云学术共收录了国内外主流学术期刊6万余种,收集的期刊论文及会议论文总量共计约1.5亿篇,并以每天添加12000余篇中外论文的速度递增。我们也可以为用户提供个性化、定制化的学者数据。欢迎来电咨询!咨询电话:010-8811{复制后删除}0370

www.globalauthorid.com

TOP

Copyright © 2019-2024 北京同舟云网络信息技术有限公司
京公网安备11010802033243号  京ICP备18003416号-3