The Chow ring of the moduli space of abelian threefolds

In this paper we determine the structure of the Chow ring of the Delaunay-Voronoi compactification (A) over tilde(3) of the moduli space of principally polarized abelian threefolds. This compactification was introduced by Namikawa and studied by Tsushima. We shall use equivariant classes on level coverings of (A) over tilde(3). We also compare this ring with the Chow ring of the moduli space of stable genus 3 curves as determined by Faber.