English

Sum-ratio estimates over arbitrary finite fields

Combinatorics 2014-07-08 v1 Number Theory

Abstract

The aim of this note is to record a proof that the estimate max{A+A,A:A}A12/11\max{\{|A+A|,|A:A|\}}\gg{|A|^{12/11}} holds for any set AFqA\subset{\mathbb{F}_q}, provided that AA satisfies certain conditions which state that it is not too close to being a subfield. An analogous result was established in \cite{LiORN}, with the product set AAA\cdot{A} in the place of the ratio set A:AA:A. The sum-ratio estimate here beats the sum-product estimate in \cite{LiORN} by a logarithmic factor, with slightly improved conditions for the set AA, and the proof is arguably a little more intuitive. The sum-ratio estimate was mentioned in \cite{LiORN}, but a proof was not given.

Keywords

Cite

@article{arxiv.1407.1654,
  title  = {Sum-ratio estimates over arbitrary finite fields},
  author = {Oliver Roche-Newton},
  journal= {arXiv preprint arXiv:1407.1654},
  year   = {2014}
}

Comments

12 pages. This note is not intended for journal publication, since the main result and proof are too similar to the work of arXiv:1106.1148. However, the subtle differences between the proof of the main result here and that of arXiv:1106.1148 mean that it is necessary to record the result carefully, particularly with future applications in mind

R2 v1 2026-06-22T04:56:49.793Z