Two-color Ramsey lower bounds for bounded degree hypergraphs

Abstract

We consider Ramsey numbers of bounded-degree uniform hypergraphs. In particular, we prove that for every $k\ge 3$, there exists a constant $c_k>0$ such that, for all sufficiently large $\Delta$ and every $n\ge 2^{\Delta }$, there is a $k$-uniform $n$-vertex hypergraph $H$ with maximum degree at most $\Delta$ satisfying \[ r(H)\ge \tw_{k-1}\!\bigl(c_kΔ\log\logΔ\bigr)\,n. \] Here $\tw_j$ denotes the tower function of height $j$. This constitutes the first progress towards a problem posed by Conlon, Fox and Sudakov.

arXiv commentThis version provides an improved lower bound