Perverse-Hodge octahedron

Abstract

The perverse-Hodge octahedron is a 3D enhancement of the Hodge diamond of a compact hyperk\"{a}hler manifold. Its existence is equivalent to Nagai's conjecture, which holds for all known deformation types. The octahedron appears implicitly in Huybrechts-Mauri and Shen-Yin.