English

Quotient sets in nonabelian groups

Group Theory 2024-04-11 v1 Combinatorics Number Theory

Abstract

We show that for a finite, nonempty subset AA of a group, the quotient set A1A:={a11a2 ⁣:a1,a2A}A^{-1}A:=\{a_1^{-1}a_2\colon a_1,a_2\in A\} has size A1A53A|A^{-1}A|\ge\frac53\,|A|, unless AA is densely contained in a coset, or in a union of two cosets of a finite subgroup.

Keywords

Cite

@article{arxiv.2404.06887,
  title  = {Quotient sets in nonabelian groups},
  author = {Vsevolod F. Lev},
  journal= {arXiv preprint arXiv:2404.06887},
  year   = {2024}
}
R2 v1 2026-06-28T15:49:45.511Z