Polynomial families of incident flags and explicit off-diagonal Ramsey graphs
Abstract
We construct explicit off-diagonal Ramsey graphs from polynomial families of incident point--hyperplane flags. Universal interpolation translates the exact dimension of ordered clique configurations into a bound on their coefficient--label incidence. At the critical dimension, a polynomial separates the forbidden-pair image from its diagonal; deleting the corresponding edges preserves a triangular rank certificate. Restriction of scalars realizes the rational endpoint without rounding loss. The resulting fixed-s exponent has leading scale s/(2log2s), and short Frobenius relations give the explicit example R(16,t)≥Ω(t2.0539221767…). A finite-fiber construction gives the range s2(log s)2=o(log t). For fixed parameters, algebraic preprocessing terminates and field initialization, vertex decoding and adjacency take deterministic time polynomial in the extension degree. We also retain an elimination-free variant and formulate the filtering argument for general forbidden configurations with a distinguished edge.
Related
BibTeX
@misc{verbeken2026polynomial,
title = {{Polynomial families of incident flags and explicit off-diagonal Ramsey graphs}},
author = {Brecht F. Verbeken},
howpublished = {arXiv},
year = {2026},
month = oct,
doi = {10.48550/arxiv.2610.06081},
eprint = {2610.06081},
archivePrefix = {arXiv},
url = {https://arxiv.org/abs/2610.06081},
note = {CC BY 4.0},
}
RIS
TY - UNPB
TI - Polynomial families of incident flags and explicit off-diagonal Ramsey graphs
AU - Brecht F. Verbeken
PY - 2026
DA - 2026/10/05
PB - arXiv
DO - 10.48550/arxiv.2610.06081
UR - https://arxiv.org/abs/2610.06081
AB - We construct explicit off-diagonal Ramsey graphs from polynomial families of incident point--hyperplane flags. Universal interpolation translates the exact dimension of ordered clique configurations into a bound on their coefficient--label incidence. At the critical dimension, a polynomial separates the forbidden-pair image from its diagonal; deleting the corresponding edges preserves a triangular rank certificate. Restriction of scalars realizes the rational endpoint without rounding loss. The resulting fixed-s exponent has leading scale s/(2log_2s), and short Frobenius relations give the explicit example R(16,t)≥Ω(t^2.0539221767…). A finite-fiber construction gives the range s^2(log s)^2=o(log t). For fixed parameters, algebraic preprocessing terminates and field initialization, vertex decoding and adjacency take deterministic time polynomial in the extension degree. We also retain an elimination-free variant and formulate the filtering argument for general forbidden configurations with a distinguished edge.
ER -