English

Small weight code words arising from the incidence of points and hyperplanes in PG($\boldsymbol{n,q}$)

Combinatorics 2021-10-26 v2

Abstract

Let Cn1(n,q)C_{n-1}(n,q) be the code arising from the incidence of points and hyperplanes in the Desarguesian projective space PG(n,qn,q). Recently, Polverino and Zullo proved that within this code, all non-zero code words of weight at most 2qn12q^{n-1} are scalar multiples of either the incidence vector of one hyperplane, or the difference of the incidence vectors of two distinct hyperplanes. We improve this result, proving that when q>17q>17 and q{25,27,29,31,32,49,121}q\notin\{25,27,29,31,32,49,121\}, all code words of weight at most (4q8q332)qn2(4q-\sqrt{8q}-\frac{33}{2})q^{n-2} are linear combinations of incidence vectors of hyperplanes through a fixed (n3)(n-3)-space. Depending on the omitted value for qq, we can lower the bound on the weight of cc to obtain the same results.

Keywords

Cite

@article{arxiv.1905.04978,
  title  = {Small weight code words arising from the incidence of points and hyperplanes in PG($\boldsymbol{n,q}$)},
  author = {Sam Adriaensen and Lins Denaux and Leo Storme and Zsuzsa Weiner},
  journal= {arXiv preprint arXiv:1905.04978},
  year   = {2021}
}