English

Polynomial extensions of Raimi's theorem

Combinatorics 2026-01-01 v3 Number Theory

Abstract

Raimi's theorem guarantees the existence of a partition of N\mathbb{N} into two parts with an unavoidable intersection property: for any finite coloring of N\mathbb{N}, some color class intersects both parts infinitely many times, after an appropriate shift (translation). We establish a polynomial extension of this result, proving that such intersections persist under polynomial shifts in any dimension. Let P(1),,P(f)Z[x]P^{(1)},\dots,P^{(f)}\in\mathbb{Z}[x] be non-constant polynomials with positive leading coefficients and P(j)(0)=0P^{(j)}(0)=0 for every jj. We construct a partition of Nk\mathbb{N}^k into an arbitrarily fixed finite number of pieces such that for any coloring of Nk\mathbb{N}^k with finitely many colors, there exist x0Nx_0\in \mathbb{N} and a single color class that meets all partition pieces after shifts by x0+P(j)(h)x_0+P^{(j)}(h) in each of the kk coordinate directions, for every jj and infinitely many values hNh\in \mathbb{N}. Our proof exploits Weyl's equidistribution theory, Pontryagin duality, and the structure of polynomial relation lattices. We also prove some finite analogues of the above results for abelian groups and SL2(Fq)SL_2(\mathbb{F}_q).

Keywords

Cite

@article{arxiv.2511.06650,
  title  = {Polynomial extensions of Raimi's theorem},
  author = {Norbert Hegyvari and Janos Pach and Thang Pham},
  journal= {arXiv preprint arXiv:2511.06650},
  year   = {2026}
}

Comments

V3: abstract revised

R2 v1 2026-07-01T07:28:50.150Z