English

A note on star-like configurations in finite settings

Number Theory 2017-08-31 v2 Combinatorics

Abstract

Given EFqdE \subset \mathbb{F}_q^d, we show that certain configurations occur frequently when EE is of sufficiently large cardinality. Specifically, we show that we achieve the statistically number of kk-stars {(x,x1,,xk)Ek+1:xxi=ti}\displaystyle\left|\left\{(x, x^1, \dots, x^k) \in E^{k+1} : \| x - x^i \| = t_i \right\}\right| when is Ekqd+12|E| \gg_k q^{\frac{d+1}{2}}. This result can be thought of as a natural generalization of the Erd\H os-Falconer distance problem. Our result improves on a pinned-version of our theorem which implied the above result, but only in the range Eqd+k2|E| \gg q^{\frac{d+k}{2}}. As an immediate corollary, this demonstrates that when Eckqd+12|E| \gg c_k q^{\frac{d+1}{2}}, then EE determines a positive proportion of all kk-stars. Our results also extend to the setting of integers mod qq.

Keywords

Cite

@article{arxiv.1309.1497,
  title  = {A note on star-like configurations in finite settings},
  author = {David Covert},
  journal= {arXiv preprint arXiv:1309.1497},
  year   = {2017}
}

Comments

Paper subsumed by arXiv:1406.0107

R2 v1 2026-06-22T01:21:48.587Z