English

A Short Character Sum in $\mathbb{F}_{p^3}$

Number Theory 2025-11-11 v3

Abstract

We establish a new bound for short character sums in finite fields, particularly over two-dimensional grids in Fp3\mathbb{F}_{p^3} and higher-dimensional lattices in Fpd\mathbb{F}_{p^d}, extending an earlier work of Mei-Chu Chang on Burgess inequality in Fp2\mathbb{F}_{p^2}. In particular, we show that for intervals of size p3/8+εp^{3/8+\varepsilon}, the sum x,yχ(x+ωy)\sum_{x, y} \chi(x + \omega y), with ωFp3Fp\omega \in \mathbb{F}_{p^3} \setminus \mathbb{F}_p, exhibits nontrivial cancellation uniformly in ω\omega. This is further generalized to codimension-one sublattices in Fpd\mathbb{F}_{p^d}, and applied to obtain an alternative estimate for character sums on binary cubic forms.

Keywords

Cite

@article{arxiv.2505.19654,
  title  = {A Short Character Sum in $\mathbb{F}_{p^3}$},
  author = {Aishik Chattopadhyay},
  journal= {arXiv preprint arXiv:2505.19654},
  year   = {2025}
}

Comments

13 pages

R2 v1 2026-07-01T02:38:41.700Z