An acyclic $d$-partition of the $r$-uniform complete hypergraph $K_{rd}^{(r)}$

Abstract

In this paper we introduce a $d$-partition $\mathcal{E}_d^{(r)}=(\Omega_1^{(r,d)}, \Omega_2^{(r,d)},\dots, \Omega_d^{(r,d)})$ of the $r$-uniform complete hypergraph $K_{rd}^{(r)}$. We prove that $\mathcal{E}_d^{(r)}$ is homogeneous and that each hypergraph $\Omega_i^{(r,d)}$ is acyclic (i.e. has zero Betti numbers). As an application, we show that the map $det^{S^r}$ is nontrivial for every $r$, which gives a partial answer to a conjecture from [14].